:root{--font-sans:-apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;--font-display:-apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue", Arial, sans-serif;--ink:#142321;--muted:#687571;--paper:#edf1ed;--panel:#fcfdfafa;--line:#203a361f;--deep:#183e3a;--teal:#287b72;--aqua:#83d8ca;--electric:#9ce5a8;--gold:#d9ab4f;--danger:#a6473c;--radius:24px;--surface-solid:#f9faf7;--surface-raised:#fbfcf9db;--surface-control:#193e3a12;--surface-selected:#287b721f;--hairline:#162e2a1a;--surface:var(--surface-raised);--surface-elevated:#fff;--surface-hover:#eaeee6;--border:var(--line);--border-strong:#162e2a38;--accent:var(--teal);--accent-deep:var(--deep);--shadow:0 18px 55px #142c2914, 0 1px 0 #ffffffdb inset;--shadow-float:0 24px 70px #10272424, 0 1px 0 #ffffffe6 inset;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}[data-theme=dark],html.dark{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--ink:#edf4f1;--muted:#8fa59f;--paper:#0c1514;--panel:#121d1be0;--line:#ffffff1a;--deep:#8ee2d4;--teal:#38b2a3;--aqua:#70dfcf;--electric:#98f3b2;--gold:#e5be65;--danger:#e26759;--surface-solid:#13211f;--surface-raised:#162421d1;--surface-control:#ffffff14;--surface-selected:#38b2a338;--hairline:#ffffff14;--surface:var(--surface-raised);--surface-elevated:#172825;--surface-hover:#1c312d;--border:var(--line);--border-strong:#bee0d63d;--accent:#38b2a3;--accent-deep:#1b4943;--shadow:0 20px 60px #00000073, 0 1px 0 #ffffff14 inset;--shadow-float:0 28px 80px #0009, 0 1px 0 #ffffff1f inset}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--ink:#edf4f1;--muted:#8fa59f;--paper:#0c1514;--panel:#121d1be0;--line:#ffffff1a;--deep:#8ee2d4;--teal:#38b2a3;--aqua:#70dfcf;--electric:#98f3b2;--gold:#e5be65;--danger:#e26759;--surface-solid:#13211f;--surface-raised:#162421d1;--surface-control:#ffffff14;--surface-selected:#38b2a338;--hairline:#ffffff14;--surface:var(--surface-raised);--surface-elevated:#172825;--surface-hover:#1c312d;--border:var(--line);--border-strong:#bee0d63d;--accent:#38b2a3;--accent-deep:#1b4943;--shadow:0 20px 60px #00000073, 0 1px 0 #ffffff14 inset;--shadow-float:0 28px 80px #0009, 0 1px 0 #ffffff1f inset}}html{background:var(--paper);color:var(--ink);scroll-padding-top:6rem}body{color:var(--ink);font-family:var(--font-sans);font-optical-sizing:auto;-webkit-font-smoothing:antialiased;text-rendering:optimizelegibility;background-color:#0000;background-image:radial-gradient(circle at 12% -10%,#6dcdbc33,#0000 30rem),radial-gradient(circle at 100% 18%,#adc2e52e,#0000 34rem),linear-gradient(#f3f5f1 0%,#ebefeb 100%);background-position:0 0,0 0,0 0;background-repeat:repeat,repeat,repeat;background-size:auto,auto,auto;background-attachment:fixed;background-origin:padding-box,padding-box,padding-box;background-clip:border-box,border-box,border-box;transition:background-color .24s,color .24s;overflow-x:clip}[data-theme=dark] html,html.dark{background:#0c1514}[data-theme=dark] body,html.dark body{color:var(--ink);background-color:#0000;background-image:radial-gradient(circle at 12% -10%,#2d7a703d,#0000 32rem),radial-gradient(circle at 100% 18%,#28466e38,#0000 36rem),linear-gradient(#0d1615 0%,#080f0e 100%);background-position:0 0,0 0,0 0;background-repeat:repeat,repeat,repeat;background-size:auto,auto,auto;background-attachment:fixed;background-origin:padding-box,padding-box,padding-box;background-clip:border-box,border-box,border-box}@media (prefers-color-scheme:dark){:root:not([data-theme=light]) html{background:#0c1514}:root:not([data-theme=light]) body{color:var(--ink);background-color:#0000;background-image:radial-gradient(circle at 12% -10%,#2d7a703d,#0000 32rem),radial-gradient(circle at 100% 18%,#28466e38,#0000 36rem),linear-gradient(#0d1615 0%,#080f0e 100%);background-position:0 0,0 0,0 0;background-repeat:repeat,repeat,repeat;background-size:auto,auto,auto;background-attachment:fixed;background-origin:padding-box,padding-box,padding-box;background-clip:border-box,border-box,border-box}}button,a,input,select{touch-action:manipulation}button,a{transition-property:background-color,border-color,color,box-shadow,opacity,transform;transition-duration:.16s;transition-timing-function:cubic-bezier(.2,.8,.2,1)}button:not(:disabled):active,a:active{transition-duration:80ms;transform:scale(.97)}button:disabled{cursor:not-allowed}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline-offset:3px;outline:3px solid #1f7e744d}.app-shell{max-width:1800px;padding:12px 24px calc(40px + env(safe-area-inset-bottom))}.panel,.molecule-library,.inspector-card,.stage-canvas-container,.stage-viewport-shell,.equation-card,.balance-panel,.learning-cards>article{background:var(--surface-raised);box-shadow:var(--shadow);-webkit-backdrop-filter:blur(28px)saturate(150%);backdrop-filter:blur(28px)saturate(150%);border-color:#ffffffb8}.topbar{min-height:68px;top:max(10px, env(safe-area-inset-top));background:#f7f9f5b8;border-color:#ffffffc2;border-radius:20px;grid-template-columns:auto minmax(0,1fr) auto;gap:16px;padding:10px 12px;box-shadow:0 14px 44px #122c2917,inset 0 1px #ffffffe6}.brand-mark{background:linear-gradient(145deg,#1d4c47,#123431);border:1px solid #ffffff29;border-radius:13px;width:40px;height:40px;box-shadow:0 8px 20px #10332f33,inset 0 1px #ffffff2e}.brand strong{font-family:var(--font-display);letter-spacing:-.025em;font-size:18px;font-weight:720}.brand em{letter-spacing:.13em;margin-top:4px;font-size:10px;font-weight:650}.main-nav{background:#183e3a0e;border:1px solid #183e3a0e;border-radius:15px;justify-self:center;gap:2px;padding:3px}.nav-link{color:#5f6d69;border-radius:11px;min-height:40px;padding-inline:14px;font-size:12px;font-weight:650}.nav-link:hover{background:#ffffff9e}.nav-link.active{color:var(--deep);background:#ffffffeb;box-shadow:0 4px 13px #132f2c17,inset 0 1px #fff}.header-action{white-space:nowrap;background:#183e3a0f;border:1px solid #183e3a0a;border-radius:12px;flex:none;min-height:40px;font-size:11px}.header-action.theme-action{border-radius:12px;justify-content:center;align-items:center;width:40px;min-width:40px;height:40px;padding:0;display:inline-flex}.header-action:hover{background:#ffffffd9;border-color:#183e3a1a;box-shadow:0 4px 14px #132f2c12}.mobile-utilities{display:none}.workspace,.molecule-grid,.reaction-workspace,.trends-grid{gap:16px;margin-top:16px}.workspace{grid-template-columns:250px minmax(470px,1fr) 360px}.molecule-grid{grid-template-columns:275px minmax(500px,1fr) 360px}.reaction-workspace{grid-template-columns:250px minmax(520px,1fr) 350px}.trends-grid{grid-template-columns:minmax(620px,1fr) 370px}.panel,.molecule-library,.inspector-card,.stage-canvas-container,.stage-viewport-shell,.equation-card,.balance-panel,.viewer-shell,.reaction-viewer,.learning-cards>article{border-radius:var(--radius)}.element-library,.reaction-library,.molecule-library{border:1px solid #ffffffbd}.panel-heading>span,.library-title-row h2,.card-heading h3{font-family:var(--font-display);letter-spacing:-.018em;font-weight:700}.library-search,.table-controls label{background:#183e3a0e;border-color:#0000;border-radius:12px;min-height:42px}.library-search:focus-within,.table-controls label:focus-within{background:#ffffffe6;border-color:#287b7273;box-shadow:0 0 0 3px #287b7214}.element-list>button,.reaction-list>button,.molecule-list-item{border-radius:14px;min-height:50px}.element-list>button:hover,.reaction-list>button:hover,.molecule-list-item:hover{background:#183e3a0e}.element-list>button.active,.reaction-list>button.active,.molecule-list-item.active{background:var(--surface-selected);border-color:#287b722b;box-shadow:inset 0 1px #ffffffa6}.view-table,.primary-button,.panel-actions .primary-button,.quiz-action-btn,.inspector-nav-link,.lab-actions .animate-button{background:linear-gradient(145deg,#204d48,#173a37);border-color:#ffffff14;box-shadow:0 7px 18px #123a3629,inset 0 1px #ffffff29}.dialog-backdrop{-webkit-backdrop-filter:blur(18px)saturate(140%);backdrop-filter:blur(18px)saturate(140%);background:#0c1c1b94}.dialog-card{background:var(--panel);border:1px solid #ffffffe6;box-shadow:0 32px 90px #0c242138,inset 0 1px #fffffff2}.viewer-shell,.reaction-viewer,.stage-canvas-container,.stage-viewport-shell{box-shadow:var(--shadow);background:radial-gradient(circle at 50% 36%,#71d5c230,#0000 46%),radial-gradient(circle at 90% 0,#a8bee329,#0000 34%),linear-gradient(155deg,#fafcf8f2,#e7ede8f5);border:1px solid #ffffffd6}.viewer-shell:before,.reaction-viewer:before{background-image:linear-gradient(#204a4808 1px,#0000 1px),linear-gradient(90deg,#204a4808 1px,#0000 1px);background-size:52px 52px}.viewer-tools,.viewer-toolbar,.stage-mode-toolbar{-webkit-backdrop-filter:blur(24px)saturate(160%);backdrop-filter:blur(24px)saturate(160%);background:#f8faf6c2;border-color:#ffffffc7;box-shadow:0 12px 34px #122d2a1a,inset 0 1px #ffffffe6}.viewer-tools button,.toolbar-btn,.toolbar-toggle-btn,.mode-tab,.filter-chip,.property-tab-chip{transition:background-color .15s,border-color .15s,color .15s,box-shadow .15s,transform 80ms ease-out}.info-panel{padding:28px 26px}.info-title h1,.reaction-title h1,.title-row h1,.trends-heading-block h1{font-family:var(--font-display);letter-spacing:-.045em;font-weight:760}.info-title h1{font-size:clamp(34px,3vw,46px);line-height:.98}.element-intro{font-family:var(--font-sans);font-size:15px;line-height:1.55}.key-facts div,.reaction-info dl div,.spec-row{border-color:var(--hairline);padding-block:9px}.key-facts dt,.reaction-info dt,.spec-row dt{letter-spacing:.055em;font-weight:650}.isotope-note,.discovery-note,.safety-note,.physics-callout{background:#287b7213;border:1px solid #287b7214;border-radius:13px}.learning-cards-header-mobile{display:none}.learning-cards{gap:16px;margin-top:16px}.learning-cards>article{min-height:250px;padding:22px}.learning-cards article header h3{font-family:var(--font-display);letter-spacing:-.02em;font-size:19px;font-weight:720}.learning-cards article header em{letter-spacing:.12em;font-size:9px;font-weight:720}@media (hover:hover) and (pointer:fine){.learning-cards article:hover{transform:translateY(-3px);box-shadow:0 22px 55px #122e2a1a,inset 0 1px #fff}}.molecule-library{height:calc(100dvh - 112px);padding:16px;top:92px}.molecule-library>.library-search{flex-shrink:0;min-width:0}.molecule-library .library-search input{min-width:0}.library-header{border-bottom-color:var(--hairline);flex-shrink:0;gap:8px}.builder-trigger-btn{background:var(--surface-selected);border-color:#287b721f}.molecule-library-close{background:var(--surface-control);cursor:pointer;border:0;border-radius:10px;flex:none;justify-content:center;align-items:center;width:34px;height:34px;display:none}.category-filter-chips{scrollbar-width:none;flex-wrap:nowrap;flex-shrink:0;margin-inline:-2px;padding:0 2px 7px;overflow-x:auto}.category-filter-chips::-webkit-scrollbar{display:none}.property-chips-scroll::-webkit-scrollbar{display:none}.mode-tabs::-webkit-scrollbar{display:none}.viewer-toolbar::-webkit-scrollbar{display:none}.filter-chip{flex:none;min-height:30px;padding-inline:11px}.stage-topbar{padding:8px 6px 2px}.molecule-iupac,.trends-subtitle,.reaction-title p{color:#64716d;line-height:1.45}.stage-canvas-container{height:calc(100dvh - 206px);min-height:500px}.molecule-library .panel-heading{gap:8px}.molecule-library .panel-heading h2{white-space:nowrap;font-size:16px}.viewer-toolbar{border:0;border-top:1px solid #ffffffbd;gap:6px;padding:8px 10px;box-shadow:0 -12px 34px #122d2a0f}.viewer-toolbar .toolbar-group{gap:4px}.viewer-toolbar .toolbar-label{margin-right:1px;font-size:9.5px}.toolbar-btn,.toolbar-toggle-btn{white-space:nowrap;background:#183e3a0b;border-color:#0000;border-radius:9px;gap:4px;min-height:30px;padding:4px 7.5px;font-size:11px}.toolbar-btn.active,.toolbar-toggle-btn.active{color:var(--deep);background:#287b7221;border-color:#287b721f}.molecule-inspector,.trends-inspector{gap:16px}.inspector-card{padding:18px}.card-heading{border-bottom-color:var(--hairline)}.lewis-svg,.selected-trend-stat-box,.cross-trend-stats,.rule-item{background:#ffffff80;border-color:#183e3a17}.trends-topbar{margin-top:22px;padding-inline:8px}.trends-heading-block h1{font-size:clamp(30px,3vw,42px)}.trends-badge{color:var(--teal);background:#287b721a;border-color:#287b721f}.property-selector-strip{border:0;margin-top:16px;padding:0;scroll-margin-top:6rem}.property-chips-scroll{scrollbar-width:none;gap:7px;padding:2px 2px 5px}.property-tab-chip{background:#fafbf8b3;border-color:#ffffffbd;border-radius:14px;min-height:44px;box-shadow:0 5px 18px #122e2a0a}.property-tab-chip.active{background:#fffffff2;border-color:#287b7233;box-shadow:0 10px 26px #1b50491a,inset 0 1px #fff}.stage-mode-toolbar{border-radius:16px;padding:7px}.mode-tab{border-radius:11px;min-height:36px;padding-inline:11px}.mode-tab.active{color:var(--deep);background:#ffffffeb;box-shadow:0 5px 16px #122f2c17}.palette-select{background:#ffffffb8;border-color:#183e3a1a;min-height:32px}.stage-viewport-shell{height:calc(100dvh - 266px);min-height:540px}.selected-trend-stat-box{border-radius:14px}.stat-value-display strong{font-family:var(--font-display);letter-spacing:-.03em;font-weight:740}.reaction-title{padding:12px 6px 2px}.reaction-title h1{font-size:clamp(32px,3.2vw,48px);line-height:.98}.reaction-title em,.info-kicker,.element-count{letter-spacing:.11em;font-weight:700}.reaction-title>span{background:#ffffff85;border-color:#183e3a1a;min-height:38px}.equation-card{border:1px solid #fffc;min-height:96px;padding:12px}.species-control{background:#ffffff85;border-color:#183e3a14;border-radius:14px}.coefficient-stepper{background:#183e3a0f;border-radius:11px}.reaction-viewer{min-height:410px}.balance-panel{border:1px solid #ffffffc2;padding:16px}.lab-actions button{border-color:#183e3a1a;border-radius:10px;min-height:38px}.lab-actions .check-button{color:var(--deep);background:#287b721f;border-color:#287b7224;font-weight:700}.reaction-info{align-self:start;padding:26px}@media (max-width:1260px){.workspace{grid-template-columns:220px minmax(440px,1fr) 330px}.molecule-grid{grid-template-columns:250px minmax(440px,1fr) 330px}.reaction-workspace{grid-template-columns:225px minmax(480px,1fr) 320px}}@media (max-width:1120px){.workspace,.reaction-workspace{grid-template-columns:210px minmax(0,1fr)}.molecule-grid,.trends-grid{flex-direction:column;display:flex}.molecule-library{height:auto;max-height:32rem;position:relative;top:0}.molecule-inspector,.trends-inspector{grid-template-columns:repeat(2,minmax(0,1fr));display:grid}.molecule-inspector>:last-child,.trends-inspector>:last-child{grid-column:1/-1}}@media (max-width:760px){:root{--radius:20px}html{scroll-padding-top:5rem}body{padding-bottom:calc(78px + env(safe-area-inset-bottom))}.app-shell{padding:7px 10px calc(24px + env(safe-area-inset-bottom))}.topbar{-webkit-backdrop-filter:blur(28px)saturate(180%);backdrop-filter:blur(28px)saturate(180%);min-height:54px;top:max(6px, env(safe-area-inset-top));background:#f7f9f5f0;grid-template-columns:34px minmax(0,1fr) auto;align-items:center;gap:7px;padding:6px 7px;display:grid}.brand{gap:0}.brand-mark{border-radius:10px;width:34px;height:34px}.brand-copy,.main-nav,.header-actions{display:none}.mobile-context-action{background:#183e3a11;border-color:#183e3a0f;border-radius:12px;max-width:none;min-height:42px;margin:0;padding:4px 10px;overflow:hidden}.mobile-context-action strong{font-size:11.5px;font-weight:720}.mobile-context-action small{font-size:10.5px}.mobile-utilities{gap:4px;display:flex}.mobile-utilities button{color:#566864;cursor:pointer;background:#183e3a0a;border:0;border-radius:12px;justify-content:center;align-items:center;width:42px;min-width:42px;height:42px;min-height:42px;padding:0;display:flex}.mobile-utilities button:active{background:#183e3a1f}.mobile-utilities svg{width:19px;height:19px}.mobile-nav{bottom:max(7px, env(safe-area-inset-bottom));box-shadow:var(--shadow-float);background:#f7f9f5c7;border-color:#ffffffd1;border-radius:20px;grid-template-columns:repeat(4,1fr);gap:3px;padding:5px;left:7px;right:7px}.mobile-nav a{color:#62716d;border-radius:15px;min-height:52px;font-size:10px;font-weight:650}.mobile-nav a.active{background:linear-gradient(145deg,#214f4a,#173a37);box-shadow:0 7px 18px #123a3633,inset 0 1px #ffffff24}.mobile-nav svg{width:19px;height:19px}.workspace,.molecule-grid,.reaction-workspace,.trends-topbar,.property-selector-strip,.trends-grid{will-change:auto;flex-direction:column;gap:12px;margin-top:12px;animation:none;display:flex}.element-library,.reaction-library,.molecule-library{bottom:0;height:auto;max-height:84dvh;padding:12px 16px calc(82px + env(safe-area-inset-bottom));pointer-events:none;visibility:hidden;z-index:95;background:#f9fbf8f0;border-radius:26px 26px 0 0;transition:transform .32s cubic-bezier(.2,.8,.2,1),visibility 0s linear .32s;display:flex;position:fixed;inset:auto 0 0;transform:translateY(104%);box-shadow:0 -22px 65px #0e252233,inset 0 1px #fff}.element-library:before,.reaction-library:before,.molecule-library:before{content:"";background:#183e3a30;border-radius:99px;flex:none;width:38px;height:5px;margin:0 auto 10px;display:block}.element-library.open,.reaction-library.open,.molecule-library.mobile-open{pointer-events:auto;visibility:visible;transition-delay:0s;transform:translateY(0)}.molecule-library-close{display:flex}.builder-trigger-btn span{display:none}.drawer-backdrop{-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);background:#0a1b195c}.viewer-shell{min-height:min(68dvh,580px)}.viewer-caption{display:none}.auto-rotate{z-index:6;background:#faf9f5f0;border:1px solid #183e3a1a;border-radius:99px;height:38px;min-height:38px;padding:0 13px;font-size:11.5px;font-weight:650;position:absolute;bottom:8px;left:8px;transform:none;box-shadow:0 2px 10px #183e3a14}.structure-guide{z-index:7;bottom:8px;left:auto;right:8px}.structure-guide-toggle{background:#faf9f5f0;border:1px solid #183e3a1a;border-radius:99px;height:38px;min-height:38px;padding:0 13px;font-size:11.5px;font-weight:650;box-shadow:0 2px 10px #183e3a14}.viewer-view-switcher{z-index:6;gap:2px;padding:2.5px;top:8px}.switcher-btn{gap:5px;min-height:36px;padding:4px 10px;font-size:11px}.orbital-bar{z-index:5;flex-direction:column;align-items:stretch;gap:5px;max-width:none;display:flex;position:absolute;top:58px;left:8px;right:8px;transform:none}.subshell-chips{overscroll-behavior-x:contain;scrollbar-width:none;-webkit-overflow-scrolling:touch;flex-wrap:nowrap;justify-content:flex-start;gap:4px;width:100%;max-width:100%;padding:2px 2px 4px;display:flex;overflow-x:auto}.subshell-chips::-webkit-scrollbar{display:none}.chip{white-space:nowrap;flex:none;min-height:34px;padding:4px 10px;font-size:11px}.orbital-legend{overscroll-behavior-x:contain;scrollbar-width:none;-webkit-overflow-scrolling:touch;background:#f9f9f5e0;border:1px solid #d8ded8;border-radius:99px;flex-wrap:nowrap;justify-content:flex-start;align-items:center;gap:8px;max-width:100%;padding:4px 12px;display:flex;overflow-x:auto}.orbital-legend::-webkit-scrollbar{display:none}.legend-item{white-space:nowrap;flex:none;gap:5px;font-size:10.5px}.info-panel,.reaction-info,.inspector-card{padding:20px 18px}.info-title h1{font-size:36px}.key-facts{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin:14px 0 0;display:grid}.key-facts div{background:#183e3a09;border:1px solid #183e3a0e;border-radius:13px;flex-direction:column;align-items:flex-start;gap:4px;padding:10px 12px;display:flex}.key-facts dt{color:var(--muted);letter-spacing:.04em;text-transform:uppercase;font-size:10.5px;font-weight:700}.key-facts dd{color:var(--deep);font-family:var(--font-mono);text-align:left;max-width:none;margin:0;font-size:13.5px;font-weight:600}.key-facts div:nth-child(4){grid-column:1/-1}.key-facts div:has(.configuration){grid-column:1/-1}.key-facts .configuration{word-break:break-all;font-size:11.5px}.panel-actions{grid-template-columns:1fr 1fr;gap:9px;margin-top:16px;display:grid}.panel-actions button,.panel-actions a,.panel-actions .primary-button{border-radius:14px;gap:8px;min-height:48px;font-size:13.5px;font-weight:650}.panel-actions .primary-button{grid-column:1/-1;min-height:50px}.learning-cards-header-mobile{justify-content:space-between;align-items:center;margin-top:8px;padding:0 4px;display:flex}.learning-cards-header-mobile span{color:var(--deep);font-family:var(--font-display,serif);font-size:16px;font-weight:700}.learning-cards-header-mobile small{color:var(--muted);letter-spacing:.05em;text-transform:uppercase;font-size:11px;font-weight:600}.learning-cards{overscroll-behavior-x:contain;scroll-snap-type:x mandatory;scrollbar-width:none;-webkit-overflow-scrolling:touch;flex-direction:row;gap:12px;margin-inline:-10px;padding:6px 12px 16px;display:flex;overflow-x:auto}.learning-cards::-webkit-scrollbar{display:none}.learning-cards>article{box-sizing:border-box;scroll-snap-align:center;scroll-snap-stop:always;border-radius:20px;flex:0 0 calc(100vw - 44px);max-width:350px;min-height:auto;padding:20px 18px;box-shadow:0 4px 18px #183e3a0f}.learning-cards>article>button,.learning-cards>article>a,.learning-cards>article .card-actions-split a,.learning-cards>article .card-actions-split button{border-radius:12px;min-height:46px;font-size:13px;font-weight:650}.stage-topbar,.trends-topbar,.reaction-title{align-items:flex-start;padding:10px 5px 2px}.title-row h1,.trends-heading-block h1,.reaction-title h1{font-size:31px;line-height:1.02}.stage-topbar .quiz-action-btn,.trends-actions .quiz-action-btn{justify-content:center;width:42px;min-width:42px;height:42px;min-height:42px;padding:0}.stage-topbar .quiz-action-btn span,.trends-actions .quiz-action-btn span,.trends-badge,.reaction-title>span{display:none}.stage-canvas-container,.stage-viewport-shell{height:62dvh;min-height:430px}.viewer-toolbar{overscroll-behavior-x:contain;scrollbar-width:none;flex-wrap:nowrap;justify-content:flex-start;gap:8px;padding:9px;overflow-x:auto}.toolbar-group{flex-wrap:nowrap;flex:none}.toolbar-label{display:none}.toolbar-btn,.toolbar-toggle-btn{white-space:nowrap;min-height:38px;font-size:11px}.molecule-inspector,.trends-inspector{flex-direction:column;gap:12px;display:flex}.property-selector-strip{margin-inline:-10px;margin-top:13px;padding-inline:0;scroll-margin-top:5rem;overflow:hidden}.property-chips-scroll{margin-inline:0;padding:2px 10px 7px;scroll-padding-inline:10px;overflow-x:auto}.property-tab-chip{flex:none;min-height:46px}.prop-unit{display:none}.stage-mode-toolbar{flex-flow:column;align-items:stretch;gap:7px;padding:6px;display:flex;overflow:hidden}.mode-tabs{scrollbar-width:none;margin-inline:-2px;padding:2px;display:flex;overflow-x:auto}.mode-tab{white-space:nowrap;flex:none;min-height:38px}.palette-controls{border-top:1px solid var(--hairline);justify-content:space-between;padding:7px 4px 2px}.exaggeration-slider{margin-left:auto}.trends-subtitle{display:none}.reaction-center{gap:12px}.reaction-title p{font-size:13px}.equation-card{border-radius:20px;padding:10px}.coefficient-stepper{border-radius:12px;padding:2px}.coefficient-stepper button{border-radius:8px;justify-content:center;align-items:center;width:38px;min-width:38px;height:38px;min-height:38px;display:flex}.coefficient-stepper b{font-size:17px}.species-control{border-radius:16px;min-height:68px;padding:8px 12px}.species-control strong{font-size:17px}.species-control small{font-size:11.5px}.reaction-viewer{min-height:390px}.balance-panel{border-radius:20px;padding:14px}.lab-actions{grid-template-columns:repeat(2,1fr);gap:8px;display:grid}.lab-actions button{border-radius:12px;min-height:46px;font-size:13px;font-weight:650}.lab-actions .check-button,.lab-actions .animate-button{min-height:48px}}@media (max-width:430px){.app-shell{padding-inline:8px}.property-selector-strip{margin-inline:-8px}.property-chips-scroll{padding-inline:8px;scroll-padding-inline:8px}.orbital-bar{top:57px;left:6px;right:6px}.topbar{gap:5px}.mobile-context-action{padding-inline:6px}.mobile-context-action>svg:not(.mobile-context-chevron){display:none}.mobile-utilities button{width:40px;min-width:40px;height:40px;min-height:40px}.mobile-nav{left:6px;right:6px}.mobile-nav a{font-size:9.5px}.stage-canvas-container,.stage-viewport-shell{min-height:400px}.info-title>span{width:58px;height:58px}.spec-row{grid-template-columns:minmax(92px,.8fr) minmax(0,1.2fr)}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@media (prefers-reduced-transparency:reduce){.topbar,.mobile-nav,.panel,.molecule-library,.inspector-card,.viewer-tools,.viewer-toolbar,.stage-mode-toolbar,.footer-panel{-webkit-backdrop-filter:none;backdrop-filter:none}:root:not([data-theme=dark]):not(.dark) .topbar,:root:not([data-theme=dark]):not(.dark) .mobile-nav,:root:not([data-theme=dark]):not(.dark) .panel,:root:not([data-theme=dark]):not(.dark) .molecule-library,:root:not([data-theme=dark]):not(.dark) .inspector-card,:root:not([data-theme=dark]):not(.dark) .viewer-tools,:root:not([data-theme=dark]):not(.dark) .viewer-toolbar,:root:not([data-theme=dark]):not(.dark) .stage-mode-toolbar,:root:not([data-theme=dark]):not(.dark) .footer-panel{background:#f8faf6}[data-theme=dark] .topbar,[data-theme=dark] .mobile-nav,[data-theme=dark] .panel,[data-theme=dark] .molecule-library,[data-theme=dark] .inspector-card,[data-theme=dark] .viewer-tools,[data-theme=dark] .viewer-toolbar,[data-theme=dark] .stage-mode-toolbar,[data-theme=dark] .footer-panel,html.dark .topbar,html.dark .mobile-nav,html.dark .panel,html.dark .molecule-library,html.dark .inspector-card,html.dark .viewer-tools,html.dark .viewer-toolbar,html.dark .stage-mode-toolbar,html.dark .footer-panel{background:#121d1b}}@media (prefers-contrast:more){:root:not([data-theme=dark]):not(.dark){--line:#39514d;--hairline:#1423215c}:root:not([data-theme=dark]):not(.dark) .topbar,:root:not([data-theme=dark]):not(.dark) .mobile-nav,:root:not([data-theme=dark]):not(.dark) .panel,:root:not([data-theme=dark]):not(.dark) .molecule-library,:root:not([data-theme=dark]):not(.dark) .inspector-card,:root:not([data-theme=dark]):not(.dark) .stage-canvas-container,:root:not([data-theme=dark]):not(.dark) .stage-viewport-shell,:root:not([data-theme=dark]):not(.dark) .equation-card,:root:not([data-theme=dark]):not(.dark) .balance-panel,:root:not([data-theme=dark]):not(.dark) .footer-panel{background:#fbfcf9;border-color:#38514d}[data-theme=dark] .topbar,[data-theme=dark] .mobile-nav,[data-theme=dark] .panel,[data-theme=dark] .molecule-library,[data-theme=dark] .inspector-card,[data-theme=dark] .stage-canvas-container,[data-theme=dark] .stage-viewport-shell,[data-theme=dark] .equation-card,[data-theme=dark] .balance-panel,[data-theme=dark] .footer-panel,html.dark .topbar,html.dark .mobile-nav,html.dark .panel,html.dark .molecule-library,html.dark .inspector-card,html.dark .stage-canvas-container,html.dark .stage-viewport-shell,html.dark .equation-card,html.dark .balance-panel,html.dark .footer-panel{background:#121d1b;border-color:#bee0d659}}.site-footer{box-sizing:border-box;max-width:1800px;padding:0 24px calc(36px + env(safe-area-inset-bottom));width:100%;margin:28px auto 0}.footer-panel{background:var(--surface-raised);border-radius:var(--radius);box-shadow:var(--shadow);-webkit-backdrop-filter:blur(28px)saturate(150%);backdrop-filter:blur(28px)saturate(150%);border:1px solid #ffffffc2;padding:36px 36px 24px;position:relative}.footer-grid{grid-template-columns:1.8fr 1fr 1.1fr 1.3fr;gap:36px 32px;display:grid}.footer-col{flex-direction:column;display:flex}.footer-col-brand .brand{text-decoration:none}.footer-desc{color:var(--muted);max-width:380px;margin:14px 0 16px;font-size:13.5px;line-height:1.55}.footer-pill-row{flex-wrap:wrap;gap:6px;display:flex}.footer-pill{background:var(--surface-control);border:1px solid var(--hairline);color:var(--deep);font-family:var(--font-mono);border-radius:99px;padding:4px 10px;font-size:11px;font-weight:600}.footer-col-title{color:var(--deep);font-family:var(--font-sans);letter-spacing:.09em;text-transform:uppercase;margin:0 0 16px;font-size:11px;font-weight:700}.footer-links{flex-direction:column;gap:11px;margin:0;padding:0;list-style:none;display:flex}.footer-link{color:var(--muted);border-radius:8px;align-items:center;gap:8px;width:fit-content;margin:-2px -4px;padding:2px 4px;font-size:13.5px;font-weight:550;text-decoration:none;transition:color .16s,transform .16s;display:inline-flex}.footer-link svg{color:var(--teal);opacity:.75;flex-shrink:0;transition:opacity .16s,transform .16s}@media (hover:hover) and (pointer:fine){.footer-link:hover{color:var(--ink);transform:translate(2px)}.footer-link:hover svg{opacity:1;transform:scale(1.1)}}.footer-pedagogy-note{border-top:1px dashed var(--hairline);color:var(--muted);margin:16px 0 0;padding-top:12px;font-size:11.5px;font-style:italic;line-height:1.45}.footer-github-card{color:var(--ink);background:linear-gradient(145deg,#1d4c470d,#12343105);border:1px solid #287b7233;border-radius:16px;flex-direction:column;padding:14px 16px;text-decoration:none;transition:transform .18s cubic-bezier(.2,.8,.2,1),box-shadow .18s cubic-bezier(.2,.8,.2,1),border-color .18s,background .18s;display:flex;box-shadow:0 2px 8px #122c2908}@media (hover:hover) and (pointer:fine){.footer-github-card:hover{background:linear-gradient(145deg,#1d4c4717,#12343108);border-color:#287b7261;transform:translateY(-2px);box-shadow:0 8px 24px #122c2914}}.github-card-header{color:var(--deep);justify-content:space-between;align-items:center;margin-bottom:8px;display:flex}.github-card-badge{color:var(--teal);font-family:var(--font-mono);background:#287b721f;border:1px solid #287b722e;border-radius:6px;padding:2px 7px;font-size:10px;font-weight:700}.github-card-body{flex-direction:column;gap:3px;display:flex}.github-card-body strong{color:var(--ink);font-family:var(--font-mono);word-break:break-all;font-size:13.5px;font-weight:700}.github-card-body span{color:var(--muted);font-size:11.5px;line-height:1.4}.github-card-footer{color:var(--teal);align-items:center;gap:6px;margin-top:10px;font-size:12px;font-weight:650;display:flex}.footer-github-sublinks{align-items:center;gap:8px;margin-top:12px;display:flex}.footer-sublink{color:var(--muted);font-size:12px;text-decoration:none;transition:color .16s}@media (hover:hover) and (pointer:fine){.footer-sublink:hover{color:var(--teal);text-decoration:underline}}.footer-sublink-dot{color:var(--hairline);font-size:12px}.footer-bottom{border-top:1px solid var(--hairline);align-items:center;margin-top:32px;padding-top:20px;display:flex}.footer-copyright{color:var(--muted);margin:0;font-size:12px}@media (max-width:1024px){.footer-grid{grid-template-columns:repeat(2,1fr);gap:28px 20px}.footer-col-brand{grid-column:1/-1}}@media (max-width:760px){.site-footer{padding:0 10px calc(24px + env(safe-area-inset-bottom));margin-top:20px}.footer-panel{border-radius:20px;padding:24px 18px 18px}.footer-grid{grid-template-columns:1fr;gap:24px}.footer-bottom{padding-top:16px}}.theme-toggle-btn{color:var(--muted);cursor:pointer;background:#183e3a0d;border:1px solid #183e3a14;border-radius:99px;justify-content:center;align-items:center;gap:6px;min-height:38px;padding:0 12px;font-size:12px;font-weight:650;transition:background-color .15s,color .15s,border-color .15s,transform .1s;display:inline-flex}.theme-toggle-btn:hover{background:var(--surface-selected);color:var(--deep);border-color:#287b7233}.theme-toggle-btn:active{transform:scale(.95)}.theme-toggle-btn .theme-icon{flex:none;transition:transform .26s cubic-bezier(.2,.8,.2,1),color .15s}.theme-toggle-btn .sun-icon{color:#eab308}.theme-toggle-btn .moon-icon{color:var(--teal)}.theme-toggle-btn:hover .sun-icon{transform:rotate(20deg)scale(1.12)}.theme-toggle-btn:hover .moon-icon{transform:rotate(-15deg)scale(1.12)}.mobile-utilities .theme-toggle-btn,.mobile-utility-btn.theme-action{color:#566864;cursor:pointer;background:#183e3a0a;border:0;border-radius:12px;justify-content:center;align-items:center;width:42px;min-width:42px;height:42px;min-height:42px;padding:0;display:flex}.mobile-utilities .theme-toggle-btn:active,.mobile-utility-btn.theme-action:active{background:#183e3a1f;transform:scale(.94)}:is([data-theme=dark],html.dark) .viewer-shell,:is([data-theme=dark],html.dark) .reaction-viewer,:is([data-theme=dark],html.dark) .stage-canvas-container,:is([data-theme=dark],html.dark) .stage-viewport-shell{box-shadow:var(--shadow);background:radial-gradient(circle at 50% 36%,#267d7338,#0000 50%),radial-gradient(circle at 90% 0,#234b732e,#0000 38%),linear-gradient(155deg,#101b19f5,#0a1211fa);border-color:#ffffff1a}:is([data-theme=dark],html.dark) .viewer-shell:before,:is([data-theme=dark],html.dark) .reaction-viewer:before{background-image:linear-gradient(#ffffff09 1px,#0000 1px),linear-gradient(90deg,#ffffff09 1px,#0000 1px)}:is([data-theme=dark],html.dark) .topbar{background:#0e1917e0;border-color:#ffffff1a;box-shadow:0 16px 45px #00000073}:is([data-theme=dark],html.dark) .brand-mark{color:#72eccd;background:linear-gradient(145deg,#1b4943,#12332f);box-shadow:0 4px 14px #00000059,inset 0 1px #ffffff26}:is([data-theme=dark],html.dark) .nav-link{color:var(--muted)}:is([data-theme=dark],html.dark) .nav-link:hover{color:var(--deep);background:#ffffff0f}:is([data-theme=dark],html.dark) .nav-link.active{color:var(--deep);background:#38b2a32e;box-shadow:inset 0 1px #ffffff1f}:is([data-theme=dark],html.dark) .header-action,:is([data-theme=dark],html.dark) .theme-toggle-btn{color:var(--muted);background:#ffffff0f;border-color:#ffffff17}:is([data-theme=dark],html.dark) .header-action:hover,:is([data-theme=dark],html.dark) .theme-toggle-btn:hover{color:var(--deep);background:#38b2a32e;border-color:#38b2a34d}:is([data-theme=dark],html.dark) .mobile-utilities button,:is([data-theme=dark],html.dark) .mobile-utilities .theme-toggle-btn{color:var(--muted);background:#ffffff0f}:is([data-theme=dark],html.dark) .mobile-utilities button:active,:is([data-theme=dark],html.dark) .mobile-utilities .theme-toggle-btn:active{background:#ffffff24}:is([data-theme=dark],html.dark) .mobile-context-action{background:#ffffff0f;border-color:#ffffff17}:is([data-theme=dark],html.dark) .mobile-nav{background:#0e1917e0;border-color:#ffffff1f;box-shadow:0 16px 45px #00000080}:is([data-theme=dark],html.dark) .mobile-nav a{color:var(--muted)}:is([data-theme=dark],html.dark) .mobile-nav a.active{color:#fff;background:linear-gradient(145deg,#1b5650,#133e3a);box-shadow:0 7px 20px #00000073,inset 0 1px #ffffff29}:is([data-theme=dark],html.dark) .viewer-tools,:is([data-theme=dark],html.dark) .viewer-toolbar,:is([data-theme=dark],html.dark) .stage-mode-toolbar{background:#121e1cf0!important;border-color:#ffffff1f!important;box-shadow:0 8px 30px #00000073!important}:is([data-theme=dark],html.dark) .viewer-tools button{color:var(--muted)!important}:is([data-theme=dark],html.dark) .viewer-tools button:hover{color:var(--deep)!important;background:#ffffff14!important}:is([data-theme=dark],html.dark) .viewer-tools button.active{color:var(--deep)!important;background:#38b2a338!important}:is([data-theme=dark],html.dark) .auto-rotate,:is([data-theme=dark],html.dark) .structure-guide-toggle{color:var(--ink)!important;background:#121e1cf0!important;border-color:#ffffff1f!important;box-shadow:0 4px 16px #00000059!important}:is([data-theme=dark],html.dark) .structure-guide.open{background:#121e1cfa!important;border-color:#ffffff1f!important;box-shadow:0 20px 55px #0009!important}:is([data-theme=dark],html.dark) .structure-options button{color:var(--muted);background:#ffffff0d;border-color:#ffffff14}:is([data-theme=dark],html.dark) .structure-options button.active{color:var(--deep);background:#38b2a338;border-color:#38b2a366}:is([data-theme=dark],html.dark) .viewer-view-switcher{background:#121e1ceb;border-color:#ffffff1f}:is([data-theme=dark],html.dark) .switcher-btn{color:var(--muted)}:is([data-theme=dark],html.dark) .switcher-btn.active{color:var(--deep);background:#38b2a338}:is([data-theme=dark],html.dark) .orbital-legend,:is([data-theme=dark],html.dark) .elevation-prop-badge,:is([data-theme=dark],html.dark) .palette-gradient-bar{color:var(--ink)!important;background:#121e1ce6!important;border-color:#ffffff1f!important}:is([data-theme=dark],html.dark) .elevation-prop-badge strong{color:var(--deep)!important}:is([data-theme=dark],html.dark) .elevation-prop-badge span,:is([data-theme=dark],html.dark) .palette-gradient-bar .gradient-labels{color:var(--muted)!important}:is([data-theme=dark],html.dark) .atomic-stamp{background:#121e1ccc;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .panel,:is([data-theme=dark],html.dark) .info-panel,:is([data-theme=dark],html.dark) .reaction-info,:is([data-theme=dark],html.dark) .molecule-library,:is([data-theme=dark],html.dark) .element-library,:is([data-theme=dark],html.dark) .reaction-library,:is([data-theme=dark],html.dark) .inspector-card,:is([data-theme=dark],html.dark) .stage-canvas-container,:is([data-theme=dark],html.dark) .stage-viewport-shell,:is([data-theme=dark],html.dark) .equation-card,:is([data-theme=dark],html.dark) .balance-panel,:is([data-theme=dark],html.dark) .learning-cards>article{background:var(--panel);border-color:var(--line)!important}:is([data-theme=dark],html.dark) .info-title>span{background:color-mix(in srgb, var(--category) 22%, #14201eeb);border-color:color-mix(in srgb, var(--category) 50%, #fff3);box-shadow:0 6px 20px #0006, 0 0 16px color-mix(in srgb, var(--category) 25%, transparent);color:var(--ink)}:is([data-theme=dark],html.dark) .info-kicker .favorite.active{color:#72eccd;background:#38b2a338}:is([data-theme=dark],html.dark) .isotope-note,:is([data-theme=dark],html.dark) .discovery-note,:is([data-theme=dark],html.dark) .safety-note,:is([data-theme=dark],html.dark) .physics-callout{background:#38b2a317;border-color:#38b2a32e}:is([data-theme=dark],html.dark) .key-facts div{background:#ffffff0a;border-color:#ffffff12}:is([data-theme=dark],html.dark) .learning-cards>article{background:#121e1ce0;border-color:#ffffff1a;box-shadow:0 12px 36px #00000059}:is([data-theme=dark],html.dark) .learning-cards article>button,:is([data-theme=dark],html.dark) .learning-cards article>a{color:var(--ink);border-color:var(--line)}:is([data-theme=dark],html.dark) .learning-cards article>button:hover,:is([data-theme=dark],html.dark) .learning-cards article>a:hover{color:var(--deep);background:#ffffff0f}:is([data-theme=dark],html.dark) .learning-cards-header-mobile span{color:var(--deep)}:is([data-theme=dark],html.dark) .learning-cards-header-mobile small{color:var(--muted)}:is([data-theme=dark],html.dark) .primary-button,:is([data-theme=dark],html.dark) .view-table,:is([data-theme=dark],html.dark) .panel-actions .primary-button,:is([data-theme=dark],html.dark) .quiz-action-btn,:is([data-theme=dark],html.dark) .inspector-nav-link,:is([data-theme=dark],html.dark) .lab-actions .animate-button{color:#edf4f1;background:linear-gradient(145deg,#2a6860,#1b4943);border-color:#ffffff29;box-shadow:0 8px 24px #0006,inset 0 1px #fff3}:is([data-theme=dark],html.dark) .panel-actions button:not(.primary-button),:is([data-theme=dark],html.dark) .panel-actions a{color:var(--ink);background:#ffffff0d;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .panel-actions button:not(.primary-button):hover,:is([data-theme=dark],html.dark) .panel-actions a:hover{color:var(--deep);background:#38b2a32e;border-color:#38b2a359}:is([data-theme=dark],html.dark) .source-links a{color:var(--muted);background:#ffffff0a;border:1px solid #ffffff14;border-radius:6px;padding:3px 7px;text-decoration:none}:is([data-theme=dark],html.dark) .source-links a:hover{color:var(--deep);background:#38b2a32e;border-color:#38b2a359}:is([data-theme=dark],html.dark) .element-library,:is([data-theme=dark],html.dark) .reaction-library,:is([data-theme=dark],html.dark) .molecule-library,:is([data-theme=dark],html.dark) .dialog-card{background:#0f1a18f5;border-color:#ffffff1f;box-shadow:0 -22px 65px #000000a6,inset 0 1px #ffffff14}:is([data-theme=dark],html.dark) .dialog-card{box-shadow:0 24px 80px #000000b3,inset 0 1px #ffffff14}:is([data-theme=dark],html.dark) .dialog-close{color:var(--ink);background:#ffffff14;border:1px solid #ffffff1f}:is([data-theme=dark],html.dark) .dialog-close:hover{color:var(--deep);background:#38b2a340;border-color:#38b2a366}:is([data-theme=dark],html.dark) .element-library:before,:is([data-theme=dark],html.dark) .reaction-library:before,:is([data-theme=dark],html.dark) .molecule-library:before,:is([data-theme=dark],html.dark) .dialog-card:before{background:#ffffff38}:is([data-theme=dark],html.dark) .drawer-backdrop,:is([data-theme=dark],html.dark) .dialog-backdrop{background:#000000a6}:is([data-theme=dark],html.dark) .library-search,:is([data-theme=dark],html.dark) .table-controls label,:is([data-theme=dark],html.dark) .palette-select,:is([data-theme=dark],html.dark) .table-controls select{color:var(--ink);background:#ffffff0f;border-color:#ffffff1f}:is([data-theme=dark],html.dark) .library-search:focus-within,:is([data-theme=dark],html.dark) .table-controls label:focus-within{border-color:var(--teal)!important;background:#ffffff17!important;box-shadow:0 0 0 3px #38b2a32e!important}:is([data-theme=dark],html.dark) .library-search input,:is([data-theme=dark],html.dark) .table-controls input{color:var(--ink)}:is([data-theme=dark],html.dark) .library-search input::placeholder,:is([data-theme=dark],html.dark) .table-controls input::placeholder{color:var(--muted)}:is([data-theme=dark],html.dark) .element-list>button,:is([data-theme=dark],html.dark) .reaction-list>button,:is([data-theme=dark],html.dark) .molecule-list-item{color:var(--ink);background:#ffffff0a;border-color:#ffffff12}:is([data-theme=dark],html.dark) .element-list>button:hover,:is([data-theme=dark],html.dark) .reaction-list>button:hover,:is([data-theme=dark],html.dark) .molecule-list-item:hover{background:#38b2a326!important;border-color:#38b2a34d!important}:is([data-theme=dark],html.dark) .element-list>button.active,:is([data-theme=dark],html.dark) .reaction-list>button.active,:is([data-theme=dark],html.dark) .molecule-list-item.active{background:#38b2a33d!important;border-color:#38b2a373!important;box-shadow:inset 0 1px #ffffff14!important}:is([data-theme=dark],html.dark) .equation-card,:is([data-theme=dark],html.dark) .balance-panel{border:1px solid var(--line)!important;background:#121e1cd9!important}:is([data-theme=dark],html.dark) .reaction-title>span{color:var(--deep)!important;background:#ffffff0f!important;border:1px solid #ffffff1a!important}:is([data-theme=dark],html.dark) .species-control{color:var(--ink)!important;background:#ffffff0d!important;border:1px solid #ffffff14!important}:is([data-theme=dark],html.dark) .coefficient-stepper{background:#ffffff0f;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .coefficient-stepper button{background:#ffffff0f;color:var(--deep)!important}:is([data-theme=dark],html.dark) .coefficient-stepper button:hover{background:#38b2a333;color:var(--deep)!important}:is([data-theme=dark],html.dark) .viewer-toolbar{border-top:1px solid var(--line)!important;box-shadow:0 -8px 24px #0006!important}:is([data-theme=dark],html.dark) .inspector-card{background:#121e1ce0;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .property-tab-chip,:is([data-theme=dark],html.dark) .mode-tab,:is([data-theme=dark],html.dark) .filter-chip{color:var(--muted);background:#ffffff0d;border-color:#ffffff14}:is([data-theme=dark],html.dark) .property-tab-chip:hover,:is([data-theme=dark],html.dark) .mode-tab:hover,:is([data-theme=dark],html.dark) .filter-chip:hover{color:var(--ink);background:#ffffff17}:is([data-theme=dark],html.dark) .property-tab-chip.active,:is([data-theme=dark],html.dark) .mode-tab.active,:is([data-theme=dark],html.dark) .filter-chip.active{color:var(--deep);background:#38b2a338;border-color:#38b2a366;box-shadow:0 6px 18px #00000059,inset 0 1px #ffffff1a}:is([data-theme=dark],html.dark) .toolbar-btn,:is([data-theme=dark],html.dark) .toolbar-toggle-btn{color:var(--muted);background:#ffffff0f;border-color:#ffffff17}:is([data-theme=dark],html.dark) .toolbar-btn.active,:is([data-theme=dark],html.dark) .toolbar-toggle-btn.active{color:var(--deep);background:#38b2a338;border-color:#38b2a359}:is([data-theme=dark],html.dark) .lewis-svg,:is([data-theme=dark],html.dark) .selected-trend-stat-box,:is([data-theme=dark],html.dark) .cross-trend-stats,:is([data-theme=dark],html.dark) .rule-item{background:#ffffff0a;border-color:#ffffff14}:is([data-theme=dark],html.dark) .footer-panel{box-shadow:var(--shadow);background:#121e1ce0;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .footer-pill{color:var(--deep);background:#ffffff0f;border-color:#ffffff17}:is([data-theme=dark],html.dark) .footer-col a{color:var(--muted)}:is([data-theme=dark],html.dark) .footer-col a:hover{color:var(--deep)}:is([data-theme=dark],html.dark) .nav-popover{background:#121e1cf5;border-color:#ffffff1f;box-shadow:0 16px 45px #00000080}:is([data-theme=dark],html.dark) .nav-item-icon{color:var(--deep);background:#38b2a326;border-color:#38b2a340}canvas:focus-visible,.atom-mount:focus-visible,.molecule-viewport:focus-visible,.reaction-viewer:focus-visible{outline:2px solid var(--accent,#38bdf8);outline-offset:-2px;box-shadow:0 0 0 4px #38bdf840}.library-search-wrapper,.table-search-wrapper{width:100%;display:block}.aufbau-dialog .dialog-card{max-width:960px}.aufbau-tabs,.solubility-tabs{border-bottom:1px solid var(--border);gap:8px;margin-bottom:16px;padding-bottom:12px;display:flex}.aufbau-tab,.solubility-tab{color:var(--muted);background:var(--surface);border:1px solid var(--border);cursor:pointer;border-radius:8px;align-items:center;gap:6px;padding:8px 14px;font-size:13px;font-weight:500;transition:all .18s;display:inline-flex}.aufbau-tab:hover,.solubility-tab:hover{color:var(--deep);border-color:var(--border-strong,#94a3b8)}.aufbau-tab.active,.solubility-tab.active{color:#fff;background:var(--accent-deep,#143536);border-color:var(--accent,#38bdf8)}.aufbau-anomaly-banner{color:var(--deep);background:#e0a9381f;border:1px solid #e0a93859;border-radius:10px;align-items:flex-start;gap:12px;margin-bottom:16px;padding:12px 16px;display:flex}.aufbau-anomaly-banner .anomaly-icon{color:#e0a938;flex-shrink:0;margin-top:2px}.aufbau-anomaly-banner .anomaly-text p{margin:4px 0 0;font-size:13px;line-height:1.45}.aufbau-anomaly-banner code{font-family:var(--font-mono);background:#00000026;border-radius:4px;padding:2px 6px;font-size:12px}.aufbau-kpi-ribbon{grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:10px;margin-bottom:18px;display:grid}.kpi-pill{background:var(--surface);border:1px solid var(--border);border-radius:10px;flex-direction:column;padding:10px 14px;display:flex}.kpi-pill span{color:var(--muted);text-transform:uppercase;letter-spacing:.5px;font-size:11px}.kpi-pill strong{color:var(--deep);font-size:15px;font-family:var(--font-mono);margin-top:3px}.subshell-rows-container{flex-direction:column;gap:10px;max-height:44vh;padding-right:6px;display:flex;overflow-y:auto}.subshell-card{background:var(--surface);border:1px solid var(--border);border-left:4px solid var(--sub-color,var(--teal));border-radius:8px;justify-content:space-between;align-items:center;gap:14px;padding:12px 14px 24px;display:flex}.subshell-card-header{align-items:center;gap:10px;min-width:140px;display:flex}.subshell-badge{font-family:var(--font-mono);color:var(--sub-color,#38bdf8);font-size:16px;font-weight:700}.subshell-type-name{color:var(--muted);font-size:12px}.subshell-occupancy{font-family:var(--font-mono);color:var(--muted);margin-left:auto;font-size:12px}.boxes-track{flex-wrap:wrap;align-items:center;gap:8px;display:flex}.orbital-box{border:1.5px solid var(--border-strong,#64748b);background:#00000014;border-radius:6px;flex-direction:column;justify-content:center;align-items:center;width:44px;height:44px;transition:all .15s;display:flex;position:relative}.orbital-box.mini{width:32px;height:32px}.orbital-box.filled{border-color:var(--sub-color,#38bdf8);background:#38bdf81a}.orbital-box.half-filled{border-color:var(--sub-color,#38bdf8);border-style:dashed}.box-spins{justify-content:center;align-items:center;gap:4px;font-size:18px;font-weight:700;line-height:1;display:flex}.spin-arrow{color:var(--sub-color,#38bdf8);display:inline-block}.spin-arrow.spin-down{color:#f43f5e}.box-label{color:var(--muted);font-size:9px;font-family:var(--font-mono);position:absolute;bottom:-16px}.aufbau-sim-controls{background:var(--surface);border:1px solid var(--border);border-radius:10px;flex-direction:column;gap:12px;margin-bottom:16px;padding:14px;display:flex}.sim-slider-row{align-items:center;gap:14px;display:flex}.sim-slider-row label{min-width:170px;font-size:13px;font-weight:500;font-family:var(--font-mono)}.sim-slider-row input[type=range]{accent-color:var(--accent,#38bdf8);flex:1}.sim-button-row{gap:8px;display:flex}.sim-btn{background:var(--accent-deep,#143536);color:#fff;border:1px solid var(--accent,#38bdf8);cursor:pointer;border-radius:6px;align-items:center;gap:6px;padding:7px 12px;font-size:12px;font-weight:500;display:inline-flex}.sim-btn.secondary{background:var(--surface);color:var(--deep);border-color:var(--border)}.aufbau-ladder-view{padding:12px}.energy-ladder-canvas{gap:20px;max-height:44vh;display:flex;overflow-y:auto}.ladder-y-axis{color:var(--muted);writing-mode:vertical-rl;border-right:2px dashed var(--border);flex-direction:column;align-items:center;gap:8px;padding:10px 4px;font-size:11px;display:flex;transform:rotate(180deg)}.ladder-rungs{flex-direction:column;flex:1;gap:8px;display:flex}.ladder-rung{background:var(--surface);border:1px solid var(--border);border-radius:8px;align-items:center;gap:16px;padding:10px 14px 20px;display:flex}.rung-label-col{min-width:60px;font-family:var(--font-mono)}.rung-boxes{gap:6px;display:flex}.aufbau-principles-footer{border-top:1px solid var(--border);grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin-top:18px;padding-top:14px;display:grid}.principle-item strong{color:var(--deep);font-size:12px}.principle-item p{color:var(--muted);margin:3px 0 0;font-size:11px;line-height:1.4}.molar-presets-row{color:var(--muted);align-items:center;gap:10px;margin-bottom:14px;padding-bottom:4px;font-size:12px;display:flex;overflow-x:auto}.preset-chips{flex-wrap:wrap;gap:6px;display:flex}.preset-chip{background:var(--surface);border:1px solid var(--border);cursor:pointer;color:var(--deep);border-radius:6px;align-items:center;gap:6px;padding:5px 10px;font-size:12px;transition:all .15s;display:inline-flex}.preset-chip:hover,.preset-chip.active{border-color:var(--accent,#38bdf8);background:#38bdf81a}.preset-chip small{font-family:var(--font-mono);color:var(--muted)}.molar-input-container{flex-direction:column;gap:6px;margin-bottom:18px;display:flex}.molar-input-container label{color:var(--muted);align-items:center;gap:6px;font-size:12px;display:flex}.formula-input-wrapper{align-items:center;display:flex;position:relative}.formula-input-wrapper input{background:var(--surface);border:1px solid var(--border-strong,#64748b);width:100%;font-size:18px;font-family:var(--font-mono);color:var(--deep);border-radius:10px;padding:12px 40px 12px 14px}.formula-clear{color:var(--muted);cursor:pointer;background:0 0;border:none;position:absolute;right:12px}.molar-total-card{background:var(--surface);border:1px solid var(--border);border-radius:12px;justify-content:space-between;align-items:center;margin-bottom:16px;padding:16px 20px;display:flex}.total-header span{color:var(--muted);text-transform:uppercase;font-size:11px}.total-header strong{font-size:24px;font-family:var(--font-mono);color:var(--deep);display:block}.total-mass-display{text-align:right}.mass-number{font-size:32px;font-weight:700;font-family:var(--font-mono);color:var(--accent,#38bdf8)}.mass-unit{color:var(--muted);margin-left:6px;font-size:14px}.mass-stacked-bar-section{margin-bottom:18px}.mass-stacked-bar-section .section-label{color:var(--muted);align-items:center;gap:6px;margin-bottom:6px;font-size:12px;display:flex}.mass-stacked-bar{background:var(--surface);border:1px solid var(--border);border-radius:7px;width:100%;height:14px;display:flex;overflow:hidden}.bar-segment{height:100%;transition:width .2s}.molar-breakdown-table{border-collapse:collapse;width:100%;margin-bottom:18px;font-size:13px}.molar-breakdown-table th{text-align:left;border-bottom:1px solid var(--border);color:var(--muted);text-transform:uppercase;padding:8px 12px;font-size:11px}.molar-breakdown-table td{border-bottom:1px solid var(--border);color:var(--deep);font-family:var(--font-mono);padding:10px 12px}.table-el-pill{align-items:center;gap:8px;display:flex}.el-color-dot{border-radius:50%;width:10px;height:10px}.percent-cell{align-items:center;gap:10px;display:flex}.mini-progress{background:var(--border);border-radius:3px;width:60px;height:6px;overflow:hidden}.mini-fill{height:100%}.table-inspect-btn{background:var(--surface);border:1px solid var(--border);cursor:pointer;color:var(--deep);border-radius:4px;align-items:center;gap:4px;padding:4px 8px;font-size:11px;display:inline-flex}.stoich-converter-card{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:16px}.converter-header{color:var(--deep);align-items:center;gap:8px;margin-bottom:12px;display:flex}.converter-header h4{margin:0;font-size:14px}.converter-grid{grid-template-columns:1fr 1fr;gap:12px;margin-bottom:12px;display:grid}.converter-input-group label{color:var(--muted);margin-bottom:4px;font-size:11px;display:block}.converter-input-group input{border:1px solid var(--border);width:100%;color:var(--deep);font-family:var(--font-mono);background:#0000001a;border-radius:6px;padding:8px 12px}.converter-readout{color:var(--deep);background:#0000001f;border-radius:8px;justify-content:space-between;padding:10px 14px;font-size:12px;display:flex}.study-card-actions{gap:10px;margin-bottom:14px;display:flex}.study-action-btn{cursor:pointer;border-radius:8px;align-items:center;gap:6px;padding:8px 16px;font-size:13px;font-weight:500;transition:all .18s;display:inline-flex}.study-action-btn.primary{background:var(--accent,#38bdf8);color:#0f172a;border:none;font-weight:600}.study-action-btn.secondary{background:var(--surface);color:var(--deep);border:1px solid var(--border)}.study-card-preview-container{background:#0003;border-radius:12px;justify-content:center;align-items:flex-start;max-height:60vh;padding:14px;display:flex;overflow-y:auto}.study-card-svg-wrapper svg{border-radius:16px;width:auto;max-width:100%;height:auto;max-height:54vh;display:block;box-shadow:0 12px 35px #0006}.study-card-tip{color:var(--muted);align-items:center;gap:8px;margin-top:12px;font-size:12px;display:flex}@media print{body *{visibility:hidden}.print-card-target,.print-card-target *{visibility:visible}.print-card-target{width:100%;position:absolute;top:0;left:0}}.solubility-filter-bar{flex-wrap:wrap;align-items:center;gap:14px;margin-bottom:14px;display:flex}.filter-item{color:var(--muted);align-items:center;gap:8px;font-size:12px;display:flex}.filter-item select{border:1px solid var(--border);background:var(--surface);color:var(--deep);font-family:var(--font-mono);border-radius:6px;padding:6px 10px}.solubility-legend-pills{gap:8px;margin-left:auto;display:flex}.legend-pill{border:1px solid var(--border);border-radius:4px;align-items:center;gap:4px;padding:3px 8px;font-size:11px;display:inline-flex}.legend-pill.state-s{color:#22c55e;background:#22c55e1f}.legend-pill.state-i{color:#ef4444;background:#ef44441f}.legend-pill.state-ss{color:#eab308;background:#eab3081f}.solubility-grid-container{border:1px solid var(--border);border-radius:8px;max-height:48vh;margin-bottom:14px;overflow:auto}.solubility-table{border-collapse:collapse;width:100%;font-size:12px}.solubility-table th{border:1px solid var(--border);background:var(--surface-solid);color:var(--deep);font-family:var(--font-mono);padding:8px 10px}.solubility-table thead th{z-index:3;position:sticky;top:0}.solubility-table th small{color:var(--muted);font-size:10px;display:block}.row-cation-th,.cation-header{background:var(--surface-solid);z-index:2;position:sticky;top:auto;left:0}.corner-th,.corner-header{background:var(--surface-solid);position:sticky;top:0;left:0;z-index:5!important}.cell-td{border:1px solid var(--border);text-align:center;padding:4px}.solubility-cell-btn{width:36px;height:32px;font-family:var(--font-mono);cursor:pointer;border:1px solid #0000;border-radius:4px;justify-content:center;align-items:center;font-size:12px;font-weight:700;transition:all .15s;display:inline-flex;position:relative}.solubility-cell-btn.state-s{color:#22c55e;background:#22c55e1f}.solubility-cell-btn.state-i{color:#ef4444;background:#ef444424}.solubility-cell-btn.state-ss{color:#eab308;background:#eab30824}.solubility-cell-btn.selected{outline:2px solid var(--accent,#38bdf8);transform:scale(1.08)}.precip-dot{background:#f43f5e;border-radius:50%;width:5px;height:5px;position:absolute;top:2px;right:2px}.solubility-detail-banner{background:var(--surface);border:1px solid var(--border);border-radius:10px;margin-bottom:16px;padding:12px 16px}.detail-status-pill{align-items:center;gap:10px;margin-bottom:6px;display:flex}.status-badge{border-radius:4px;padding:2px 8px;font-size:11px;font-weight:600}.status-badge.state-s{color:#052e16;background:#22c55e}.status-badge.state-i{color:#450a0a;background:#ef4444}.status-badge.state-ss{color:#422006;background:#eab308}.rules-cards-grid{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:10px;margin-top:10px;display:grid}.rule-card{background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:10px 12px}.rule-card strong{color:var(--deep);margin-bottom:4px;font-size:12px;display:block}.rule-card p{color:var(--muted);margin:0;font-size:11px;line-height:1.4}.displacement-simulator-card{background:var(--surface);border:1px solid var(--border);border-radius:12px;margin-bottom:18px;padding:16px}.displacement-inputs-row{flex-wrap:wrap;align-items:center;gap:14px;margin:14px 0;display:flex}.disp-group{flex-direction:column;gap:4px;display:flex}.disp-group label{color:var(--muted);font-size:11px}.disp-group select{border:1px solid var(--border);color:var(--deep);font-family:var(--font-mono);background:#0000001a;border-radius:6px;padding:8px 12px}.plus-sign{color:var(--muted);margin-top:16px;font-size:20px;font-weight:700}.displacement-result-box{border:1px solid var(--border);border-radius:8px;padding:14px}.displacement-result-box.success{background:#22c55e1a;border-color:#22c55e4d}.displacement-result-box.neutral{background:#94a3b814}.result-header{align-items:center;gap:8px;margin-bottom:6px;display:flex}.result-icon.ok{color:#22c55e}.result-icon.no{color:#f59e0b}.result-equation code{font-family:var(--font-mono);color:var(--deep);margin:6px 0;font-size:15px;font-weight:700;display:block}.result-explanation{color:var(--muted);margin:0;font-size:12px;line-height:1.45}.activity-ladder-track{gap:8px;padding:12px 4px;display:flex;overflow-x:auto}.ladder-metal-node{background:var(--surface);border:1px solid var(--border);text-align:center;border-radius:8px;flex-direction:column;align-items:center;min-width:68px;padding:8px 6px;transition:all .15s;display:flex}.ladder-metal-node.active-a{background:#38bdf826;border-color:#38bdf8}.ladder-metal-node.active-b{background:#eab30826;border-color:#eab308}.ladder-rank{color:var(--muted);font-size:10px}.ladder-sym{font-size:18px;font-family:var(--font-mono);color:var(--deep)}.ladder-name{color:var(--muted);font-size:10px}.ladder-potential{font-size:10px;font-family:var(--font-mono);color:#38bdf8;margin-top:4px}.mobile-context-chevron{color:var(--muted);opacity:.8;flex:none;margin-left:auto;width:14px!important;height:14px!important}.header-kbd{color:var(--muted);font-family:var(--font-mono);background:#183e3a14;border:1px solid #183e3a1f;border-radius:5px;margin-left:2px;padding:2px 5px;font-size:9.5px;font-weight:600;line-height:1}@media (min-width:761px){.viewer-tools button[data-tooltip]{position:relative}.viewer-tools button[data-tooltip]:after{background:var(--deep);color:#fff;content:attr(data-tooltip);font-family:var(--font-sans);letter-spacing:.01em;opacity:0;pointer-events:none;white-space:nowrap;z-index:25;border:1px solid #ffffff2e;border-radius:8px;padding:6px 9px;font-size:11px;font-weight:600;line-height:1;transition:opacity .14s,transform .14s;position:absolute;top:50%;left:calc(100% + 10px);transform:translate(-4px,-50%);box-shadow:0 6px 18px #0c201e38}.viewer-tools button[data-tooltip]:hover:after,.viewer-tools button[data-tooltip]:focus-visible:after{opacity:1;transform:translateY(-50%)}.coefficient-stepper{gap:2px;padding:3px}.coefficient-stepper button{border-radius:6px;justify-content:center;align-items:center;width:26px;min-width:26px;height:22px;min-height:22px;transition:background-color .14s,transform .1s;display:flex}.coefficient-stepper button:hover{background:#287b7224}.coefficient-stepper button svg{width:14px;height:14px}}.species-control{cursor:pointer;transition:border-color .15s,box-shadow .15s}.species-control:focus-visible{outline:none;box-shadow:0 0 0 3px #287b722e;border-color:var(--teal)!important}.atom-balance-bars{flex-direction:column;grid-column:1/-1;gap:2px;min-width:0;margin-top:2px;display:flex}.atom-balance-bars em{border-radius:99px;height:3.5px;font-style:normal;transition:width .2s,background-color .2s;display:block}.atom-balance-bars .bar-left{background:var(--teal)}.atom-balance-bars .bar-right{background:#d97706}.atom-counts>div.balanced .atom-balance-bars .bar-right{background:#16a34a}.mobile-scroll-gutter,.mobile-touch-guard{display:none}@media (max-width:760px){.mobile-scroll-gutter{touch-action:pan-y;z-index:4;width:20px;display:block;position:absolute;top:0;bottom:0}.mobile-scroll-gutter.left{left:0}.mobile-scroll-gutter.right{right:0}.mobile-touch-guard{color:var(--muted);cursor:pointer;z-index:6;background:#faf9f5e6;border:1px solid #183e3a1f;border-radius:99px;align-items:center;gap:5px;min-height:30px;padding:4px 10px;font-size:10.5px;font-weight:650;display:inline-flex;position:absolute;top:48px;right:10px;box-shadow:0 2px 10px #122c2914}.mobile-touch-guard.active{color:var(--deep);background:#287b7224;border-color:#287b7247}.stage-canvas-container .mobile-touch-guard,.reaction-viewer .mobile-touch-guard{top:12px}.representation-legend{max-width:calc(100% - 115px);bottom:12px;left:12px}.reaction-reset-view{bottom:12px;right:12px}}.ion-lab-trigger{-webkit-backdrop-filter:blur(8px);color:var(--deep);cursor:pointer;z-index:6;background:#f9f9f5eb;border:1px solid #cfd8d2;border-radius:99px;align-items:center;gap:5px;min-height:29px;padding:5px 11px;font-size:10.5px;font-weight:650;transition:background-color .15s,border-color .15s,transform .1s;display:inline-flex;position:absolute;top:17px;left:70px}.ion-lab-trigger:hover,.ion-lab-trigger.active{color:var(--deep);background:#e2eee9;border-color:#bfd6ce}.ion-lab-dot{background:var(--teal);border-radius:50%;width:6px;height:6px}.ion-isotope-panel{-webkit-backdrop-filter:blur(16px);border:1px solid var(--line);z-index:12;background:#fcfbf7f7;border-radius:15px;flex-direction:column;gap:10px;width:min(305px,100% - 84px);padding:13px 14px;display:flex;position:absolute;top:54px;left:70px;box-shadow:0 18px 46px #10282629}.ion-isotope-panel header,.ion-lab-header{justify-content:space-between;align-items:center;display:flex}.ion-isotope-panel header span,.ion-lab-header strong{color:var(--teal);letter-spacing:.1em;text-transform:uppercase;align-items:center;gap:6px;font-size:10.5px;font-weight:700;display:flex}.ion-isotope-panel header div,.ion-lab-header-actions{align-items:center;gap:6px;display:flex}.ion-isotope-panel .ion-reset-btn,.ion-lab-reset{color:var(--deep);cursor:pointer;background:#287b721f;border:1px solid #287b7233;border-radius:6px;align-items:center;gap:4px;padding:4px 8px;font-size:10.5px;font-weight:600;display:inline-flex}.ion-isotope-panel header button:last-child,.ion-lab-close{color:var(--muted);cursor:pointer;background:0 0;border:0;border-radius:6px;align-items:center;padding:4px;display:flex}.ion-lab-close:hover{color:var(--deep);background:#183e3a14}.ion-lab-controls{flex-direction:column;gap:8px;display:flex}.ion-isotope-readout{border:1px solid var(--hairline);background:#183e3a0d;border-radius:11px;align-items:center;gap:11px;padding:8px 10px;display:flex}.nuclide-badge{background:var(--surface-selected);border:1px solid #287b7240;border-radius:9px;grid-template-columns:auto auto;align-items:center;min-width:54px;padding:5px 8px;display:grid}.nuclide-badge sup{color:var(--muted);font-family:var(--font-mono);grid-column:1;font-size:9px;line-height:1}.nuclide-badge sub{color:var(--muted);font-family:var(--font-mono);grid-area:2/1;font-size:9px;line-height:1}.nuclide-badge b{color:var(--deep);font-family:var(--font-display);grid-area:1/2/3;margin-left:3px;font-size:22px;line-height:1}.nuclide-badge i{color:var(--teal);font-family:var(--font-mono);grid-area:1/3;margin-left:2px;font-size:10px;font-style:normal;font-weight:700}.nuclide-meta{flex-direction:column;gap:2px;min-width:0;display:flex}.nuclide-meta strong{font-size:11.5px;line-height:1.2}.nuclide-meta strong.stable{color:#15803d}.nuclide-meta strong.radioactive{color:#b45309}.nuclide-meta strong.unstable{color:#b91c1c}.nuclide-meta small{color:var(--muted);font-size:9.5px;line-height:1.35}.ion-control-row,.ion-lab-row{border:1px solid var(--hairline);background:#183e3a09;border-radius:10px;justify-content:space-between;align-items:center;padding:7px 10px;display:flex}.ion-control-row>span,.ion-lab-label{flex-direction:column;gap:2px;display:flex}.ion-control-row small,.ion-lab-label span{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;font-size:9.5px;font-weight:700}.ion-control-row b,.ion-lab-label strong{color:var(--ink);font-family:var(--font-mono);font-size:11.5px}.ion-stepper,.ion-lab-stepper{background:#183e3a0f;border-radius:9px;align-items:center;gap:6px;padding:3px 5px;display:flex}.ion-stepper button,.ion-lab-stepper button{border:1px solid var(--line);color:var(--deep);cursor:pointer;background:#fff;border-radius:6px;justify-content:center;align-items:center;width:26px;height:26px;display:flex}.ion-stepper button:disabled,.ion-lab-stepper button:disabled{opacity:.35}.ion-stepper span,.ion-lab-stepper output{color:var(--ink);font-family:var(--font-mono);text-align:center;min-width:28px;font-size:11.5px;font-weight:700}.ion-lab-footer{border-top:1px solid var(--hairline);flex-wrap:wrap;justify-content:space-between;align-items:center;gap:6px 8px;padding-top:8px;display:flex}.stability-badge{letter-spacing:.04em;text-transform:uppercase;border-radius:99px;padding:2px 8px;font-size:10px;font-weight:700}.stability-badge.stable{color:#15803d;background:#16a34a24}.stability-badge.radioactive{color:#b45309;background:#d9770629}.stability-badge.synthetic,.stability-badge.unstable{color:#b91c1c;background:#dc262624}.ion-lab-footer .decay-mode,.ion-lab-footer .half-life,.ion-lab-footer .mass-number{color:var(--muted);font-family:var(--font-mono);font-size:10.5px;font-style:normal}.atomic-stamp b sup{color:var(--teal);font-family:var(--font-mono);margin-left:2px;font-size:14px}@media (max-width:760px){.ion-lab-trigger{top:46px;left:10px}.ion-isotope-panel{width:auto;top:82px;left:10px;right:10px}}.temp-toggle-btn{color:var(--deep);cursor:pointer;font-family:var(--font-mono);white-space:nowrap;background:#183e3a0f;border:1px solid #183e3a1f;border-radius:11px;justify-content:center;align-items:center;gap:6px;min-height:38px;padding:0 12px;font-size:11px;font-weight:650;transition:background-color .15s,border-color .15s;display:inline-flex}.temp-toggle-btn:hover,.temp-toggle-btn.active{background:var(--surface-selected);border-color:var(--teal);color:var(--deep)}.temperature-scrubber-bar{border:1px solid var(--hairline);background:#183e3a0b;border-radius:14px;flex-direction:column;gap:10px;margin-bottom:10px;padding:12px 14px;display:flex}.temp-scrubber-main,.temp-slider-row{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.temp-label,.temp-readout{color:var(--deep);align-items:center;gap:6px;min-width:195px;font-size:12px;display:inline-flex}.temp-label strong,.temp-readout strong{font-family:var(--font-mono)}.temp-label small,.temp-readout small{color:var(--muted);font-family:var(--font-mono)}.temperature-scrubber-bar input[type=range]{accent-color:var(--teal);cursor:pointer;flex:1;min-width:160px}.temp-presets{flex-wrap:wrap;gap:5px;display:flex}.temp-presets button,.phase-tally-pills button,.phase-filter-pills button,.phase-filter-pills .phase-pill{border:1px solid var(--hairline);color:var(--muted);cursor:pointer;background:#ffffffc7;border-radius:99px;align-items:center;gap:5px;padding:4px 10px;font-size:10.5px;font-weight:600;transition:all .14s;display:inline-flex}.phase-filter-pills button i{font-family:var(--font-mono);font-size:10px;font-style:normal;font-weight:700}.temp-presets button.active,.phase-tally-pills button.active,.phase-filter-pills button.active,.phase-filter-pills .phase-pill.active{background:var(--deep);border-color:var(--deep);color:#fff}.phase-tally-pills,.phase-filter-pills{flex-wrap:wrap;gap:6px;display:flex}.phase-dot{border-radius:50%;width:7px;height:7px;display:inline-block}.phase-pill.solid .phase-dot{background:#2563eb}.phase-pill.liquid .phase-dot{background:#0891b2}.phase-pill.gas .phase-dot{background:#d97706}.phase-pill.unknown .phase-dot{background:#64748b}.tile-phase-tag{font-family:var(--font-mono);border-radius:4px;padding:1px 3px;font-style:normal;font-weight:700;line-height:1;position:absolute;top:3px;right:3px;font-size:7px!important}.tile-phase-tag.phase-solid{color:#1e40af;background:#1e40af24}.tile-phase-tag.phase-liquid{color:#0e7490;background:#0e74902e}.tile-phase-tag.phase-gas{color:#b45309;background:#b4530929}.periodic-grid>button{position:relative}.periodic-mobile-bar{display:none}@media (max-width:760px){.periodic-mobile-bar{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:6px;margin-bottom:6px;display:flex}.periodic-mobile-jumps{scrollbar-width:none;gap:4px;display:flex;overflow-x:auto}.periodic-mobile-jumps::-webkit-scrollbar{display:none}.periodic-mobile-jumps button{color:var(--deep);cursor:pointer;background:#183e3a12;border:1px solid #183e3a1f;border-radius:99px;flex:none;min-height:28px;padding:3px 9px;font-size:10px;font-weight:650}}.command-palette-dialog{max-width:640px!important;padding:20px!important}.cmd-palette-search{background:#183e3a0e;border:1px solid #287b7240;border-radius:14px;align-items:center;gap:10px;min-height:48px;margin-bottom:12px;padding:0 14px;display:flex}.cmd-palette-search svg{color:var(--teal);flex-shrink:0}.cmd-palette-search input{color:var(--ink);background:0 0;border:0;outline:none;width:100%;font-size:15px}.cmd-clear-btn{color:var(--muted);cursor:pointer;background:#183e3a14;border:0;border-radius:6px;justify-content:center;align-items:center;padding:4px 6px;font-size:11px;display:inline-flex}.cmd-kbd{border:1px solid var(--hairline);color:var(--muted);font-family:var(--font-mono);background:#183e3a12;border-radius:6px;padding:2px 6px;font-size:10px;font-weight:600}.cmd-palette-results{flex-direction:column;gap:4px;max-height:52vh;padding-right:4px;display:flex;overflow-y:auto}.cmd-result-item{color:var(--ink);cursor:pointer;text-align:left;background:0 0;border:1px solid #0000;border-radius:12px;grid-template-columns:40px minmax(0,1fr) auto;align-items:center;gap:12px;width:100%;min-height:52px;padding:7px 10px;transition:background-color .12s,border-color .12s;display:grid}.cmd-result-item.active,.cmd-result-item:hover{background:var(--surface-selected);border-color:#287b7238}.cmd-result-badge,.cmd-item-icon{color:var(--deep);font-family:var(--font-mono);background:#287b721f;border:1px solid #287b7233;border-radius:9px;justify-content:center;align-items:center;width:36px;height:36px;font-size:12px;font-weight:700;display:flex}.cmd-result-copy,.cmd-item-copy{flex-direction:column;gap:2px;min-width:0;display:flex}.cmd-result-copy strong,.cmd-item-copy strong{font-size:13.5px;font-weight:650}.cmd-result-copy small,.cmd-item-copy span{color:var(--muted);text-overflow:ellipsis;white-space:nowrap;font-size:11px;overflow:hidden}.cmd-item-meta{align-items:center;gap:8px;display:inline-flex}.cmd-result-kind,.cmd-badge{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;white-space:nowrap;background:#183e3a0f;border-radius:99px;padding:3px 8px;font-size:9.5px;font-style:normal;font-weight:650}.cmd-result-arrow,.cmd-item-meta svg{color:var(--muted);flex-shrink:0}.cmd-empty-state,.cmd-empty{color:var(--muted);text-align:center;padding:28px 12px;font-size:13px}.cmd-palette-footer{border-top:1px solid var(--hairline);color:var(--muted);flex-wrap:wrap;gap:14px;margin-top:12px;padding-top:10px;font-size:11px;display:flex}.cmd-palette-footer kbd{border:1px solid var(--hairline);font-family:var(--font-mono);background:#183e3a12;border-radius:4px;padding:1px 5px;font-size:10px}.custom-equation-dialog{max-width:680px!important}.custom-eq-intro{color:var(--muted);margin:-8px 0 14px;font-size:13.5px;line-height:1.5}.custom-eq-form label{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;margin-bottom:6px;font-size:11px;font-weight:700;display:block}.custom-eq-input-row,.custom-eq-input-group{align-items:center;gap:8px;display:flex;position:relative}.custom-eq-input{color:var(--ink);font-family:var(--font-mono);background:#183e3a0d;border:1px solid #287b7247;border-radius:12px;flex:1;width:100%;min-height:46px;padding:0 38px 0 14px;font-size:16px}.custom-eq-clear{color:var(--muted);cursor:pointer;background:#183e3a14;border:0;border-radius:8px;justify-content:center;align-items:center;width:28px;height:28px;display:inline-flex;position:absolute;right:10px}.custom-eq-presets,.custom-eq-Presets{flex-flow:wrap;align-items:center;gap:6px;margin:14px 0 16px;display:flex}.custom-eq-presets>span,.presets-label{color:var(--muted);letter-spacing:.05em;text-transform:uppercase;margin-right:4px;font-size:11px;font-weight:700}.preset-chips-row{flex-wrap:wrap;gap:6px;display:flex}.custom-eq-presets button,.preset-eq-chip{border:1px solid var(--hairline);color:var(--deep);cursor:pointer;text-align:left;background:#183e3a0e;border-radius:99px;flex-direction:column;gap:2px;padding:5px 12px;font-size:11.5px;font-weight:650;transition:all .14s;display:inline-flex}.custom-eq-presets button:hover,.custom-eq-presets button.active,.preset-eq-chip:hover{background:var(--surface-selected);border-color:var(--teal);color:var(--deep)}.custom-eq-presets button small,.preset-eq-chip small{color:var(--muted);font-family:var(--font-mono);font-size:9.5px}.custom-eq-error{color:#943f33;background:#f6e5df;border:1px solid #e4c2b5;border-radius:12px;align-items:center;gap:8px;padding:12px 14px;font-size:13px;display:flex}.custom-eq-solution{flex-direction:column;gap:16px;display:flex}.solution-banner{background:#287b7212;border:1px solid #287b722e;border-radius:16px;flex-direction:column;gap:12px;padding:16px;display:flex}.custom-eq-solution-header,.solution-header{color:var(--teal);letter-spacing:.08em;text-transform:uppercase;align-items:center;gap:6px;font-size:11px;font-weight:700;display:flex}.custom-eq-balanced-formula,.solution-equation{border:1px solid var(--hairline);font-family:var(--font-mono);background:#ffffffb8;border-radius:12px;flex-wrap:wrap;justify-content:center;align-items:center;gap:8px;padding:14px;font-size:18px;display:flex}.eq-term{align-items:center;gap:3px;display:inline-flex}.eq-term b.coeff-highlight,.eq-coeff{background:var(--deep);color:#fff;border-radius:6px;margin-right:3px;padding:2px 6px;font-style:normal;font-weight:700}.eq-plus,.eq-arrow{color:var(--teal);margin-inline:4px;font-weight:700}.conservation-ledger{flex-direction:column;gap:8px;display:flex}.custom-eq-conservation h4,.conservation-ledger h4,.ledger-title{color:var(--muted);letter-spacing:.06em;text-transform:uppercase;align-items:center;gap:6px;margin:0;font-size:11px;font-weight:700;display:inline-flex}.conservation-grid,.ledger-grid{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:8px;display:grid}.conservation-pill,.conservation-card{background:#ffffffbf;border:1px solid #22c55e4d;border-radius:10px;flex-direction:column;align-items:center;gap:4px;padding:10px 12px;display:flex}.conservation-pill strong,.cons-sym{color:var(--deep);font-family:var(--font-mono);font-size:15px;font-weight:700}.conservation-pill span,.cons-detail{color:var(--ink);font-family:var(--font-mono);text-align:center;flex-direction:column;align-items:center;gap:3px;font-size:11.5px;display:flex}.cons-detail strong{color:#4ade80;font-size:12px}.cons-detail small{color:var(--muted);font-size:10.5px}.conservation-pill small,.cons-check{color:#15803d;font-size:9.5px;font-style:normal;font-weight:700}:is([data-theme=dark],html.dark) .header-kbd,:is([data-theme=dark],html.dark) .cmd-kbd,:is([data-theme=dark],html.dark) .cmd-palette-footer kbd{color:var(--muted);background:#ffffff14;border-color:#ffffff24}:is([data-theme=dark],html.dark) .ion-lab-trigger,:is([data-theme=dark],html.dark) .mobile-touch-guard{color:var(--ink);background:#121e1cf0;border-color:#8ee2d438}:is([data-theme=dark],html.dark) .ion-lab-trigger:hover,:is([data-theme=dark],html.dark) .ion-lab-trigger.active{color:var(--deep);background:#38b2a32e;border-color:#8ee2d46b}:is([data-theme=dark],html.dark) .ion-isotope-panel{background:#0f1a18fa;border-color:#8ee2d433;box-shadow:0 20px 55px #000000a6}:is([data-theme=dark],html.dark) .ion-isotope-readout,:is([data-theme=dark],html.dark) .ion-control-row,:is([data-theme=dark],html.dark) .ion-lab-row,:is([data-theme=dark],html.dark) .ion-stepper,:is([data-theme=dark],html.dark) .ion-lab-stepper{background:#ffffff0d;border-color:#ffffff1a}:is([data-theme=dark],html.dark) .ion-stepper button,:is([data-theme=dark],html.dark) .ion-lab-stepper button{color:var(--ink);background:#162421;border-color:#8ee2d438}:is([data-theme=dark],html.dark) .stability-badge.stable,:is([data-theme=dark],html.dark) .cons-check{color:#4ade80}:is([data-theme=dark],html.dark) .stability-badge.radioactive{color:#fbbf24}:is([data-theme=dark],html.dark) .stability-badge.synthetic,:is([data-theme=dark],html.dark) .stability-badge.unstable{color:#f87171}:is([data-theme=dark],html.dark) .temp-toggle-btn,:is([data-theme=dark],html.dark) .temperature-scrubber-bar,:is([data-theme=dark],html.dark) .cmd-palette-search,:is([data-theme=dark],html.dark) .custom-eq-input,:is([data-theme=dark],html.dark) .custom-eq-presets button,:is([data-theme=dark],html.dark) .preset-eq-chip{color:var(--ink);background:#13211f;border-color:#8ee2d42e}:is([data-theme=dark],html.dark) .temp-presets button,:is([data-theme=dark],html.dark) .phase-tally-pills button,:is([data-theme=dark],html.dark) .phase-filter-pills button,:is([data-theme=dark],html.dark) .phase-filter-pills .phase-pill,:is([data-theme=dark],html.dark) .custom-eq-balanced-formula,:is([data-theme=dark],html.dark) .solution-equation,:is([data-theme=dark],html.dark) .conservation-pill,:is([data-theme=dark],html.dark) .conservation-card{color:var(--ink);background:#162421;border-color:#8ee2d42e}:is([data-theme=dark],html.dark) .temp-presets button.active,:is([data-theme=dark],html.dark) .phase-tally-pills button.active,:is([data-theme=dark],html.dark) .phase-filter-pills button.active,:is([data-theme=dark],html.dark) .phase-filter-pills .phase-pill.active,:is([data-theme=dark],html.dark) .eq-term b.coeff-highlight,:is([data-theme=dark],html.dark) .eq-coeff{background:var(--teal);border-color:var(--teal);color:#06211e}:is([data-theme=dark],html.dark) .tile-phase-tag.phase-solid{color:#93c5fd;background:#3b82f63d}:is([data-theme=dark],html.dark) .tile-phase-tag.phase-liquid{color:#67e8f9;background:#06b6d442}:is([data-theme=dark],html.dark) .tile-phase-tag.phase-gas{color:#fcd34d;background:#f59e0b42}:is([data-theme=dark],html.dark) .custom-eq-error{color:#fca5a5;background:#7f1d1d47;border-color:#f8717159}:is([data-theme=dark],html.dark) .cmd-item-icon,:is([data-theme=dark],html.dark) .cmd-result-badge{color:var(--deep);background:#38b2a329;border-color:#8ee2d43d}:is([data-theme=dark],html.dark) .cmd-badge,:is([data-theme=dark],html.dark) .cmd-result-kind,:is([data-theme=dark],html.dark) .cmd-clear-btn,:is([data-theme=dark],html.dark) .custom-eq-clear{color:var(--muted);background:#ffffff14}
:root{--muted:#52635e}html[data-theme=dark]{--muted:#aec0ba}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--muted:#aec0ba}}.lesson-invitation,.lesson-journey,.first-task{background:var(--surface-solid);color:var(--ink);border-radius:18px;margin-top:16px;padding:16px 20px}.lesson-invitation{grid-template-columns:minmax(0,1fr) auto 40px;align-items:center;gap:16px;display:grid}.lesson-invitation>div{min-width:0}.first-task{justify-content:space-between;align-items:center;gap:20px;display:flex}.lesson-invitation strong,.first-task strong{font-size:17px;line-height:1.4;display:block}.lesson-invitation span{color:var(--muted);margin-top:3px;font-size:14px;display:block}.lesson-invitation a,.lesson-next{flex-shrink:0;align-items:center;gap:10px;min-height:44px;font-size:14px;font-weight:650;display:inline-flex}.lesson-next{background:var(--deep);color:var(--paper);border:0;border-radius:10px;padding:10px 16px;text-decoration:none}.lesson-heading{align-items:center;gap:16px;display:flex}.lesson-heading strong{font-size:20px}.lesson-heading>span{color:var(--muted);margin-left:auto;font-size:14px}.lesson-heading>button,.first-task-close{background:var(--surface-control);color:var(--ink);border:0;border-radius:8px;place-items:center;min-width:44px;min-height:44px;display:grid}.lesson-progress{flex-wrap:wrap;gap:8px;margin:12px 0;padding:0;list-style:none;display:flex}.lesson-progress li{background:var(--surface-control);color:var(--muted);border-radius:6px;align-items:center;gap:5px;padding:6px 10px;font-size:13px;display:flex}.lesson-progress li[aria-current=step]{background:var(--deep);color:var(--paper)}.lesson-progress li.complete{color:var(--deep)}.lesson-journey>p{max-width:85ch;margin:12px 0;font-size:16px;line-height:1.55}.lesson-prediction [role=group]{flex-wrap:wrap;gap:8px;display:flex}.lesson-prediction [role=group] button{color:var(--ink);background:var(--surface-control);text-align:left;border:2px solid #0000;border-radius:10px;min-height:48px;padding:12px;font-size:15px}.lesson-prediction [role=group] button[aria-pressed=true]{border-color:var(--teal)}.lesson-prediction>p{margin:16px 0;font-size:16px;line-height:1.55}.first-task{background:var(--surface-selected)}.first-task>div{flex:1}.first-task p{margin:5px 0 0;font-size:15px;line-height:1.5}.first-task .primary-button{flex-shrink:0;min-height:44px;padding:10px 16px}.concept-help{vertical-align:middle;text-transform:none;letter-spacing:normal;font-weight:400;display:inline-flex}.concept-help>button{cursor:pointer;color:var(--deep);background:var(--surface-control);width:28px;min-width:28px;height:28px;min-height:28px;font:650 14px var(--font-sans);border:0;border-radius:50%;place-items:center;display:inline-grid}.concept-dialog{max-width:420px}.concept-dialog p{color:var(--ink);margin:16px 0 0;font-size:17px;line-height:1.65}.concept-row{align-items:center;gap:8px;padding-top:12px;font-size:14px;display:flex}.key-facts dt,.reaction-info dt,.spec-row dt,.cs-label,.source-links>span{font-family:var(--font-sans);letter-spacing:0;text-transform:none;color:var(--muted);font-size:13px;line-height:1.5}.key-facts dt{align-items:center;gap:4px;display:flex}.key-facts dd,.key-facts .configuration{font-size:14px;line-height:1.5}.key-facts>div{grid-template-columns:minmax(0,1fr) fit-content(55%);align-items:center;gap:16px;padding:12px}.key-facts dt{flex-wrap:wrap;min-width:0}.key-facts dd{overflow-wrap:anywhere;min-width:0;max-width:none}.key-facts .configuration{word-break:normal}.element-intro,.learning-cards article p,.spec-insight,.reaction-info>p{font-size:16px;line-height:1.6}.isotope-note p,.discovery-note p{font-size:13px;line-height:1.5}.isotope-note b,.discovery-note b,.info-kicker b,.card-kicker,.element-count,.learning-cards-header-mobile small{letter-spacing:0;text-transform:none;font-size:13px}.source-links a{font-size:13px}.panel-actions{flex-direction:column;align-items:stretch;gap:8px;display:flex}.panel-actions .primary-button{min-height:48px;font-size:15px}.panel-actions .suggested-action{color:var(--muted);margin:0;font-size:13px;line-height:1.5}.more-study-tools summary{cursor:pointer;background:var(--surface-control);border-radius:10px;min-height:44px;padding:12px;font-size:15px;font-weight:650}.study-tools-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;padding-top:10px;display:grid}.panel-actions .study-tools-grid button,.panel-actions .study-tools-grid a{white-space:normal;height:auto;min-height:44px;padding:10px;font-size:14px;line-height:1.4}.advanced-controls-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:18px;display:grid}.advanced-controls-grid button{min-height:52px;color:var(--ink);background:var(--surface-control);text-align:left;border:0;border-radius:10px;align-items:center;gap:10px;padding:12px;font-size:15px;display:flex}.advanced-controls-grid button[aria-pressed=true]{background:var(--surface-selected)}.mobile-element-summary,.viewer-tools .mobile-more-controls{display:none}.quiz-review{text-align:left;width:100%}.quiz-review h3{margin:16px 0;font-size:18px}.quiz-review article{background:var(--surface-control);border-radius:12px;margin-top:10px;padding:16px}.quiz-result .quiz-review article strong{font-size:16px;line-height:1.5;display:block}.quiz-result .quiz-review p{max-width:none;margin:10px 0;font-size:15px;line-height:1.6}.quiz-review a{color:var(--deep);align-items:center;gap:8px;font-size:14px;text-decoration:underline;display:inline-flex}.quiz-result-actions{flex-wrap:wrap;justify-content:center;gap:12px;margin-top:16px;display:flex}.quiz-result-actions button{border:0;border-radius:10px;align-items:center;gap:8px;min-height:44px;padding:12px;display:inline-flex}.practice-dialog .quiz-options button{font-size:16px;line-height:1.45}.practice-dialog .quiz-explanation{font-size:16px;line-height:1.6}@media (max-width:760px){.lesson-invitation,.first-task{gap:12px;padding:14px}.first-task{flex-wrap:wrap}.lesson-invitation{grid-template-columns:minmax(0,1fr) 40px;gap:8px 12px}.lesson-invitation>div{grid-area:1/1}.lesson-invitation>a{grid-area:2/1;justify-self:start;min-height:44px}.lesson-invitation-close{grid-area:1/2/3;align-self:start}.first-task{padding-right:50px;position:relative}.first-task>div{flex-basis:100%}.first-task-close{background:0 0;position:absolute;top:6px;right:6px}.first-task .primary-button{font-size:14px}.lesson-journey{padding:14px}.lesson-heading{gap:8px}.lesson-heading strong{font-size:18px}.lesson-heading>span{white-space:nowrap;font-size:13px}.lesson-progress{gap:5px}.lesson-progress li{padding:5px 7px;font-size:12px}.lesson-progress li:not([aria-current=step]):not(.complete){display:none}.lesson-next{justify-content:center;width:100%}.lesson-prediction [role=group]{flex-direction:column}.mobile-element-summary{z-index:5;justify-content:space-between;align-items:center;gap:10px;display:flex;position:absolute;top:12px;left:14px;right:14px}.mobile-element-summary strong{letter-spacing:-.03em;font-size:22px;display:block}.mobile-element-summary span{color:var(--muted);font-size:12px;line-height:1.5;display:block}.mobile-element-summary>span{text-align:right;max-width:120px}.workspace>.viewer-shell{height:530px;min-height:530px;max-height:none}.viewer-shell .atom-mount{top:138px;bottom:120px}.viewer-shell .atomic-stamp{display:none}.viewer-shell .viewer-view-switcher{justify-content:center;width:auto;top:72px;left:12px;right:12px;transform:none}.viewer-shell .switcher-btn{white-space:nowrap;flex:1;min-height:40px;padding:6px;font-size:13px}.viewer-shell .switcher-btn span{white-space:nowrap}.viewer-shell .mobile-touch-guard{background:var(--surface-solid);min-height:36px;color:var(--ink);font-size:12px;top:122px;right:12px}.viewer-shell>.ion-lab-trigger{display:none}.viewer-shell .ion-isotope-panel{width:auto;max-width:none;max-height:290px;top:120px;left:12px;right:12px;overflow-y:auto}.viewer-tools{background:var(--surface-solid);border-radius:12px;grid-template-columns:repeat(4,minmax(0,1fr));gap:4px;width:auto;max-width:none;height:56px;padding:2px;display:grid;position:absolute;inset:auto 10px 66px;overflow:visible;transform:none}.viewer-tools button{border-radius:8px;flex-direction:column;justify-content:center;align-items:center;gap:5px;width:100%;min-width:0;height:52px;min-height:52px;padding:4px;display:flex}.viewer-tools button span{clip-path:none;white-space:nowrap;width:auto;height:auto;font-size:12px;position:static;overflow:visible}.viewer-tools .advanced-tool{display:none}.viewer-tools .mobile-more-controls{display:flex}.viewer-tools button[data-tooltip]:after{display:none}.viewer-shell .auto-rotate,.viewer-shell .structure-guide-toggle{background:var(--surface-solid);height:44px;min-height:44px;color:var(--ink);padding:8px 12px;font-size:12px}.viewer-shell .auto-rotate{bottom:12px;left:12px}.viewer-shell .structure-guide{bottom:12px;right:12px}.viewer-shell .structure-guide.open{background:var(--surface-solid);width:auto;max-height:330px;left:12px;right:12px;overflow-y:auto}.viewer-shell .orbital-bar{max-width:none;max-height:none;padding:0;top:120px;left:12px;right:12px;overflow:visible}.key-facts dt{letter-spacing:0;text-transform:none;flex-wrap:wrap;font-size:13px}.key-facts>div{align-items:flex-start;gap:6px}.key-facts dd,.key-facts .configuration{font-size:14px}.panel-actions{display:flex}.practice-dialog .quiz-result{padding:12px 0}}@media (max-width:480px){.key-facts>div:last-child{grid-column:1/-1}.key-facts>div:has(.concept-help){grid-column:1/-1}}@media (prefers-reduced-motion:reduce){.lesson-invitation *,.lesson-journey *,.first-task *{scroll-behavior:auto;transition:none}}.first-task~.lesson-invitation{display:none}.atom-fallback.valence-highlighted .fallback-shell:not(:last-of-type){opacity:.2}.atom-fallback.valence-highlighted .fallback-shell:last-of-type{border-color:var(--teal);border-width:2px}.atom-fallback.valence-highlighted .fallback-shell:last-of-type i{background:var(--teal)}.cross-stat-row .cs-label,.cross-stat-row .cs-val,.spec-row dd{font-size:13px}.reaction-info dd,.reaction-info>ol li,.trends-inspector .trend-description{font-size:14px;line-height:1.6}.mobile-trend-property{display:none}@media (max-width:760px){.lesson-invitation strong{font-size:16px}.lesson-invitation>a{font-size:13px}.first-task~.lesson-invitation{display:none}.mobile-trend-property{color:var(--muted);gap:8px;margin:16px 0;font-size:14px;display:grid}.mobile-trend-property select{width:100%;min-height:48px;color:var(--ink);background:var(--surface-solid);border:1px solid var(--line);border-radius:10px;padding:10px 12px;font-size:16px}#trend-property-selector{display:none}.trends-workspace .mode-tabs{grid-template-columns:repeat(2,minmax(0,1fr));width:100%;display:grid;overflow:visible}.trends-workspace .mode-tab{white-space:normal;width:100%;min-width:0;min-height:44px;font-size:12px}.trends-workspace .stage-mode-toolbar{overflow:visible}.quiz-action-btn span{display:inline}.quiz-action-btn{width:auto;min-height:44px;padding:10px 14px}.trends-topbar{flex-wrap:wrap;gap:12px}.trends-actions{margin-left:auto}}@media (min-width:761px) and (max-width:1120px){.workspace>.viewer-shell,.workspace>.element-library{height:620px;min-height:620px;max-height:620px}.viewer-shell .mobile-element-summary{z-index:5;justify-content:space-between;align-items:center;gap:12px;display:flex;position:absolute;top:14px;left:18px;right:18px}.mobile-element-summary strong{font-size:22px;display:block}.mobile-element-summary span{color:var(--muted);font-size:12px;line-height:1.5;display:block}.viewer-shell .atomic-stamp{display:none}.viewer-shell .viewer-view-switcher{width:auto;top:76px;left:72px;right:12px;transform:none}.viewer-shell .switcher-btn{white-space:nowrap;flex:1;min-height:40px;padding:8px;font-size:12px}.viewer-shell>.ion-lab-trigger{top:128px;left:72px}.viewer-shell .viewer-tools{top:178px}.viewer-shell .atom-mount{top:160px;bottom:80px}}@media (max-width:760px){.learning-cards{max-width:100%;margin-inline:0;padding-inline:0}}@media (min-width:761px) and (max-width:1120px){.topbar{grid-template-columns:minmax(0,1fr) auto;gap:8px 16px}.topbar>.brand{grid-area:1/1}.topbar .header-actions{grid-area:1/2}.topbar .main-nav{grid-area:2/1/auto/-1;justify-content:center;justify-self:stretch;width:auto;min-width:0}.topbar .header-kbd{display:none}}@media (min-width:1121px) and (max-width:1200px){.topbar{gap:12px}.topbar .nav-link{padding-inline:12px}.topbar .header-kbd{display:none}}.reaction-info .info-kicker{gap:8px}.reaction-info h3{margin:24px 0 16px;font-size:18px;line-height:1.4}.reaction-info>ol{gap:14px;display:grid}.reaction-info>ol li{margin:0;padding-left:34px}.reaction-info>ol li:before{width:22px;height:22px;font-size:10px;top:1px}.reaction-info .safety-note{margin-top:20px;padding:14px}.reaction-info .safety-note p{margin-top:8px;font-size:13px;line-height:1.6}.reaction-info .related-elements{margin:24px 0 20px}.reaction-info .related-elements>span{margin-bottom:10px;font-size:11px}.reaction-info .related-elements>div{gap:8px}.reaction-info .related-elements button{width:48px;height:48px;padding:6px 8px}.reaction-info .related-elements small{font-size:9px}.reaction-info .related-elements b{font-size:20px}.reaction-info>.primary-button{gap:12px;min-height:48px;padding:12px 16px;font-size:14px;line-height:1.4}.reaction-info>.primary-button>svg{flex:none;width:18px;height:18px}
.mobile-molecule-controls,.mobile-reaction-actions,.mobile-resource-pagination,.mobile-trend-view{display:none}.app-tools-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:20px;display:grid}.app-tools-grid>button,.app-tools-grid>a{background:var(--surface-control);min-height:54px;color:var(--ink);text-align:left;border:0;border-radius:10px;align-items:center;gap:10px;padding:12px;font-size:15px;line-height:1.4;display:flex}.control-field{gap:8px;margin-top:20px;font-size:15px;display:grid}.control-field select,.mobile-trend-view select,.focus-controls select{width:100%;min-height:44px;color:var(--ink);background:var(--surface-solid);border:1px solid var(--line);border-radius:8px;padding:10px;font-size:16px}.lesson-invitation-close{width:40px;min-height:44px;color:var(--muted);background:0 0;border:0;border-radius:8px;place-items:center;display:grid}.viewer-expand{border:1px solid var(--line);background:var(--surface-solid);min-height:40px;color:var(--ink);z-index:7;border-radius:10px;align-items:center;gap:6px;padding:8px 12px;font-size:13px;display:inline-flex;position:absolute;top:76px;right:18px}.reaction-viewer>.viewer-expand{top:70px}.molecule-iupac,.reaction-title p{color:var(--muted);font-size:14px;line-height:1.5}.stage-topbar .quiz-action-btn,.trends-actions .quiz-action-btn{width:auto;min-width:70px;height:auto;min-height:44px;color:var(--paper);padding:10px 12px;font-size:14px}.stage-topbar .quiz-action-btn span,.trends-actions .quiz-action-btn span{display:inline}.trend-display-settings{color:var(--ink);font-size:14px}.trend-display-settings>summary{cursor:pointer;background:var(--surface-control);border-radius:8px;min-height:44px;padding:12px}.trend-display-settings .palette-controls{flex-wrap:wrap;padding:12px 0}.trend-display-settings .palette-select{background:var(--surface-solid);min-height:44px;font-size:14px}.stage-viewport-shell:has(.focused-trend-table){height:auto;min-height:0}.focused-trend-table{padding:20px}.focus-controls{grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:12px;display:grid}.focus-controls label{color:var(--muted);gap:6px;font-size:14px;display:grid}.focused-trend-table h2{letter-spacing:-.02em;margin:24px 0 8px;font-size:22px}.focused-trend-table p{color:var(--muted);font-size:15px;line-height:1.6}.focused-trend-rows{gap:6px;margin-top:18px;display:grid}.focused-trend-rows button{text-align:left;min-height:60px;color:var(--ink);background:var(--surface-control);border:2px solid #0000;border-radius:10px;grid-template-columns:36px minmax(0,1fr) minmax(80px,auto);align-items:center;gap:10px;padding:10px;display:grid}.focused-trend-rows button[aria-pressed=true]{border-color:var(--teal);background:var(--surface-selected)}.focused-symbol{font-size:20px;font-weight:700}.focused-name{font-size:14px}.focused-trend-rows strong{text-align:right;overflow-wrap:anywhere;max-width:145px;font-size:14px}.focused-meter{background:var(--surface-control);border-radius:3px;height:5px;margin-top:8px;display:block;overflow:hidden}.focused-meter i{background:var(--teal);height:100%;display:block}.focus-note{margin:18px 0 0}.footer-disclosure>summary{color:var(--deep);margin-bottom:16px;font-size:14px;font-weight:650;list-style:none}.footer-disclosure>summary::-webkit-details-marker{display:none}.is-expanded,.viewer-shell.is-expanded,.reaction-viewer.is-expanded{z-index:1000!important;background:var(--surface-solid)!important;border-radius:0!important;width:100vw!important;height:100dvh!important;min-height:0!important;max-height:none!important;margin:0!important;position:fixed!important;inset:0!important}html.viewer-expanded .app-shell,html.viewer-expanded .workspace,html.viewer-expanded .molecule-grid,html.viewer-expanded .molecule-center-stage,html.viewer-expanded .stage-canvas-container,html.viewer-expanded .reaction-workspace,html.viewer-expanded .reaction-center,html.viewer-expanded .trends-grid,html.viewer-expanded .trends-center-stage,html.viewer-expanded .stage-viewport-shell{transform-style:flat!important;perspective:none!important;filter:none!important;-webkit-backdrop-filter:none!important;backdrop-filter:none!important;contain:none!important;transform:none!important}@media (min-width:761px){.footer-disclosure>summary{pointer-events:none}}@media (max-width:760px){.topbar .mobile-context-action{flex:auto;width:auto;min-width:0;max-width:none;padding:4px 8px}.mobile-context-action>span{min-width:0}.mobile-context-action strong,.mobile-context-action small{white-space:nowrap;text-overflow:ellipsis;overflow:hidden}.topbar .mobile-utilities{flex:none;gap:4px}.topbar .mobile-utilities>button{width:44px;min-width:44px;height:44px;min-height:44px}.topbar .mobile-utilities>.mobile-tools-trigger{width:58px;min-width:58px;font-size:13px;font-weight:650}.lesson-invitation>a{gap:5px}.lesson-invitation>div>span{font-size:13px}.workspace>.viewer-shell{height:480px;min-height:480px}.workspace>.viewer-shell:has(.orbital-bar){height:560px;min-height:560px}.viewer-shell .viewer-expand{min-height:38px;padding:6px 10px;font-size:12px;top:122px;left:12px;right:auto}.viewer-shell .mobile-touch-guard{min-height:38px;padding:6px 10px;font-size:12px;top:122px;right:12px}.viewer-shell .atom-mount{top:164px;bottom:122px}.viewer-shell .orbital-bar{max-width:none;max-height:none;top:120px;left:12px;right:12px;overflow:visible}:is(.viewer-shell:has(.orbital-bar) .viewer-expand,.viewer-shell:has(.orbital-bar) .mobile-touch-guard){top:198px}.viewer-shell:has(.orbital-bar) .atom-mount{top:240px;bottom:122px}.viewer-shell,.reaction-viewer,.molecule-viewer-shell,.trend-elevation-shell{touch-action:pan-y}.viewer-shell.touch-active,.reaction-viewer.touch-active,.molecule-viewer-shell.touch-active,.trend-elevation-shell.touch-active{cursor:grab}.stage-canvas-container{height:clamp(360px,54svh,440px);min-height:0}.molecule-viewer-shell{flex:1 1 0;min-height:0}.molecule-viewer-shell>canvas{position:absolute;inset:0}.molecule-viewer-shell .viewer-floating-top{flex-wrap:wrap;gap:6px;display:flex;top:12px;left:12px;right:12px}.molecule-badge,.polarity-badge{max-width:100%;min-height:32px;padding:6px 9px;font-size:12px}.molecule-badge span{font-size:12px}.stage-canvas-container .mobile-touch-guard{min-height:40px;font-size:12px;top:62px;right:12px}.molecule-viewer-shell .viewer-floating-bottom{bottom:12px;left:12px;right:12px}.viewer-floating-bottom .viewer-icon-btn{background:var(--surface-solid);min-height:40px;font-size:12px}.stage-canvas-container .desktop-molecule-controls{display:none}.mobile-molecule-controls{background:var(--surface-solid);flex:none;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;padding:8px;display:grid;position:relative}.mobile-molecule-controls button{background:var(--surface-control);min-height:52px;color:var(--ink);border:0;border-radius:8px;flex-direction:column;justify-content:center;align-items:center;gap:5px;padding:6px;font-size:12px;display:flex}.mobile-molecule-controls button[aria-pressed=true]{background:var(--surface-selected);color:var(--deep)}.reaction-viewer{height:340px;min-height:340px}.reaction-viewer .reaction-side{top:14px;right:14px}.reaction-viewer .reaction-side small{display:none}.reaction-viewer .reaction-side strong{font-size:15px}.reaction-viewer .mobile-touch-guard{min-height:40px;font-size:12px;top:64px;right:12px}.reaction-viewer>.viewer-expand{top:64px;left:12px;right:auto}.reaction-viewer .representation-legend{display:none}.reaction-viewer .viewer-tip{top:12px;left:12px}.equation-card .coefficient-stepper{flex-direction:row;align-items:center;gap:1px;width:auto}.equation-card .coefficient-stepper button{width:32px;min-width:32px;height:44px;min-height:44px}.equation-card .coefficient-stepper b{text-align:center;min-width:20px}.equation-card .species-control{flex-direction:column;align-items:center;gap:5px;min-height:0;padding:8px}.equation-card .species-control>div{text-align:center}.mobile-reaction-actions{background:var(--surface-solid);z-index:20;border-radius:12px;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px;padding:8px;display:grid;position:sticky;top:74px}.mobile-reaction-actions>button{background:var(--deep);min-height:44px;color:var(--paper);border:0;border-radius:8px;justify-content:center;align-items:center;gap:8px;font-size:14px;font-weight:650;display:flex}.mobile-reaction-actions>button:disabled{opacity:.45}.mobile-atom-counts{color:var(--muted);flex-wrap:wrap;grid-column:1/-1;justify-content:space-between;gap:4px 8px;font-size:12px;display:flex}.mobile-atom-counts strong{color:var(--deep)}.lab-actions .check-button,.lab-actions .animate-button{display:none}.stage-topbar{align-items:flex-start;gap:10px}.stage-topbar .molecule-title-block{min-width:0}.stage-topbar .quiz-action-btn,.trends-actions .quiz-action-btn{flex-shrink:0}.molecule-iupac,.reaction-title p{font-size:14px}.isotope-note p,.discovery-note p,.resource-expand-btn,.reaction-strategy li,.reaction-strategy>p,.attempt-tracker,.attempt-tracker em{font-size:13px;line-height:1.55}.learning-cards article header em{letter-spacing:0;font-size:12px}.learning-cards-header-mobile{flex-direction:column;align-items:flex-start;gap:5px}.learning-cards-header-mobile small{text-transform:none;letter-spacing:0;font-size:13px}.learning-cards{scroll-snap-type:x mandatory}.learning-cards>article{scroll-snap-align:start}.mobile-resource-pagination{grid-template-columns:repeat(6,minmax(0,1fr));gap:5px;margin:8px 0 20px;display:grid}.mobile-resource-pagination button{background:var(--surface-control);min-width:0;min-height:44px;color:var(--ink);border:0;border-radius:8px;font-size:14px}.mobile-resource-pagination button[aria-current=page]{background:var(--deep);color:var(--paper)}.trends-workspace .mode-tabs{display:none}.mobile-trend-view{gap:8px;width:100%;font-size:14px;display:grid}.trends-workspace .stage-mode-toolbar{padding:12px}.trend-display-settings{width:100%}.focused-trend-table{padding:14px}.focused-trend-rows button{grid-template-columns:30px minmax(0,1fr) minmax(70px,auto);gap:7px;padding:8px}.focused-trend-rows strong{max-width:125px;font-size:13px}.trends-workspace .stage-viewport-shell{height:auto;min-height:0}.trend-elevation-shell{min-height:420px}.elevation-floating-top{grid-template-columns:minmax(0,1fr);gap:8px;display:grid;top:12px;left:12px;right:12px}.elevation-prop-badge{box-sizing:border-box;width:100%;min-width:0;padding:8px 10px;font-size:13px}.elevation-prop-badge>span{display:none}.elevation-floating-top .palette-gradient-bar{box-sizing:border-box;width:100%;min-width:0;max-width:none;padding:10px}.palette-gradient-bar .gradient-labels{justify-content:space-between;gap:10px;font-size:12px;display:flex}.gradient-labels>span{white-space:normal;min-width:0;max-width:50%}.gradient-labels>span:last-child{text-align:right}.trend-elevation-shell .mobile-touch-guard{min-height:40px;font-size:12px;top:120px;right:12px}.trend-elevation-shell .elevation-canvas-mount{position:absolute;inset:0}.site-footer .footer-grid{gap:0}.footer-col-brand{padding-bottom:16px}.footer-col-brand .footer-desc{margin-block:12px;font-size:14px}.footer-disclosure{padding-block:6px}.footer-disclosure>summary{cursor:pointer;justify-content:space-between;align-items:center;min-height:48px;margin:0;font-size:15px;display:flex}.footer-disclosure>summary:after{content:"+";font-size:22px}.footer-disclosure[open]>summary:after{content:"−"}.footer-disclosure .footer-links{padding:8px 0 16px}.footer-disclosure .footer-github-card{margin-top:10px}.site-footer .footer-col{min-width:0}.site-footer .footer-bottom{margin-top:16px}.is-expanded .atom-mount{top:156px;bottom:122px}.molecule-viewer-shell.is-expanded>canvas{position:absolute;inset:0}}.focused-trend-rule>summary{cursor:pointer;min-height:44px;color:var(--deep);padding:10px 0;font-size:14px}@media (max-width:760px){.trends-topbar{flex-flow:row;align-items:center}.trends-heading-block{min-width:0}.trends-heading-block h1{font-size:26px}.trends-topbar .trends-actions{margin:0}.trends-workspace .stage-mode-toolbar{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;display:grid}.stage-mode-toolbar .mobile-trend-property,.stage-mode-toolbar .mobile-trend-view{gap:7px;margin:0;font-size:13px;display:grid}.stage-mode-toolbar .mobile-trend-property select,.stage-mode-toolbar .mobile-trend-view select{min-height:46px;padding:8px;font-size:14px}.trend-display-settings{grid-column:1/-1}.focused-trend-table h2{margin-top:18px}.equation-card.compact-equation{flex-direction:row;align-items:center;gap:5px;padding:8px;display:flex}.compact-equation .equation-side{flex-wrap:nowrap;gap:4px;min-width:0;display:flex}.compact-equation .equation-side:first-child{flex:var(--reactant-count)}.compact-equation .equation-side:last-child{flex:var(--product-count)}.compact-equation .species-control{flex:1;min-width:0;padding:6px 2px}.compact-equation .species-control small{white-space:normal}.compact-equation .reaction-arrow{flex:0 0 20px;width:20px;font-size:20px;transform:none}.compact-equation .coefficient-stepper button{width:24px;min-width:24px}.molecule-viewer-shell .viewer-floating-bottom{flex-wrap:wrap;justify-content:space-between;gap:8px;display:flex}.viewer-floating-bottom .measure-status{box-sizing:border-box;flex:0 0 100%;order:-1;justify-content:center;min-height:38px}}.stage-topbar .quiz-action-btn,.trends-actions .quiz-action-btn{background:var(--deep);color:var(--paper)}@media (max-width:760px){:is(.viewer-shell:not(:has(.orbital-bar)) .viewer-expand,.viewer-shell:not(:has(.orbital-bar)) .mobile-touch-guard){top:124px}:is(.viewer-shell:not(:has(.orbital-bar)) .atom-mount,.is-expanded:not(:has(.orbital-bar)) .atom-mount){top:166px}:is(.viewer-shell:has(.orbital-bar) .viewer-expand,.viewer-shell:has(.orbital-bar) .mobile-touch-guard){top:198px}:is(.viewer-shell:has(.orbital-bar) .atom-mount,.is-expanded:has(.orbital-bar) .atom-mount){top:240px}}.focused-name{overflow-wrap:anywhere}@media (max-width:360px){.stage-canvas-container{height:clamp(320px,48svh,360px)}}@media (max-width:360px) and (max-height:780px){.stage-canvas-container{height:clamp(280px,44svh,340px)}}