.frontier{--frontier-teal:#356e70;--frontier-force:#9b681d;--frontier-purple:#79618a;--frontier-red:#a14e43;--frontier-blue:#456d96}
body.frontier .frontier-page{max-width:1200px;margin:0 auto;padding:28px 32px 0}.frontier-title{margin:0 0 24px}.frontier .eyebrow{font-size:11px;letter-spacing:.15em;color:#727b73;margin:0}.frontier-title h1{font-size:32px!important;line-height:1.5;margin:6px 0}.frontier-title>p:last-child{font-size:14px;color:#6a746d;margin:0}.case-tabs{display:grid;grid-template-columns:repeat(3,1fr);border-top:1px solid #cbd1c7;border-bottom:1px solid #cbd1c7;margin-bottom:27px}.case-tabs a{padding:12px 17px;text-decoration:none;font-size:16px;line-height:1.7;border-bottom:3px solid transparent}.case-tabs a:first-child{padding-left:0}.case-tabs a span{display:block;font-size:11px;color:#798277}.case-tabs a[aria-current]{color:#28585a;background:#f1f4ed;border-bottom-color:#356e70}.case-tabs a[aria-current]:first-child{padding-left:17px}.case-tabs a:hover{background:#f6f7f1}.case-heading .paper-tag{font:11px/1.8 system-ui,sans-serif;color:#747d73;letter-spacing:.02em}.case-heading h2{font-size:25px!important;line-height:1.6;font-weight:600;margin:6px 0 15px}.learning-bridge{display:flex;gap:20px;align-items:baseline;color:#657065;font-size:13px;line-height:1.8;margin-bottom:22px;flex-wrap:wrap}.learning-bridge span{display:flex;gap:9px;align-items:baseline}.learning-bridge b{font-size:10px;color:#8b9285;font-weight:400;white-space:nowrap}.learning-bridge strong{font-weight:400;color:#365b53}.frontier-workspace{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;align-items:start}.model-panel{min-width:0}.figure-label{display:flex;justify-content:space-between;gap:18px;font-size:10px;color:#7d877a;padding:8px 0;border-top:1px solid #aebdaf}.frontier-figure{margin:0;background:#f7f8f2;border:1px solid #dce1d6}.frontier-figure svg{width:100%;display:block;aspect-ratio:780/380;max-height:380px;font-family:TextbookSong,serif}.frontier-figure svg text{fill:#48554b;font-size:16px}.frontier-figure svg .small{font-size:13px;fill:#7c8578}.frontier-figure svg .charge{font-family:Georgia,serif;font-size:24px}.frontier-figure svg .field-label{fill:var(--frontier-teal)}.frontier-figure svg .force-label{fill:var(--frontier-force)}.frontier-figure svg .dipole-label{fill:var(--frontier-purple)}.frontier-figure figcaption{font-size:11px;color:#7b8476;padding:7px 15px;border-top:1px solid #e0e5d9;line-height:1.7}.primary-control{padding:16px 0 10px}.control-title{display:flex;justify-content:space-between;font-size:14px;gap:15px;align-items:center;margin-bottom:10px}.control-title output{font:14px/1.5 Georgia,serif;color:#28585a}.control-row{display:flex;align-items:center;gap:12px}.frontier button,.frontier input,.frontier textarea{font:inherit}.frontier button{cursor:pointer;border:1px solid #b7c3b4;background:transparent;color:#355c51;padding:7px 14px;font-size:13px;line-height:1.7;border-radius:2px}.frontier button:hover:not(:disabled){background:#edf2e8;border-color:#708e7a}.frontier button:disabled{opacity:.45;cursor:not-allowed}.frontier .primary{background:#355d56;color:#fffefa;border-color:#355d56}.frontier .primary:hover:not(:disabled){background:#254840;color:white}.frontier button[aria-pressed="true"]{border-color:#355d56;background:#e8efe3;box-shadow:inset 0 -2px #355d56}.frontier input[type="range"]{width:100%;accent-color:#356e70;cursor:pointer}.frontier input[type="range"]:disabled{opacity:.45;cursor:not-allowed}.control-lock{font-size:11px;line-height:1.7;color:#828b7e;margin:9px 0}.readout-strip{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px 25px;border-top:1px solid #d9dfd1;border-bottom:1px solid #d9dfd1;padding:12px 0}.readout-strip p{margin:0;font-size:11px;color:#7d8578;line-height:1.8}.readout-strip strong{display:block;font:17px/1.7 Georgia,TextbookSong,serif;color:#3b5f53;overflow-wrap:anywhere}.notebook{border-top:2px solid #587c68;padding-top:11px;min-width:0}.stage-label{display:flex;gap:12px;font-size:11px;color:#9ba193;padding-bottom:11px;border-bottom:1px solid #e0e4d9}.stage-label .active{color:#355d56;font-weight:600}.notebook h3{font-size:17px!important;line-height:1.7;margin:17px 0 7px}.notebook p{font-size:12px;line-height:1.85;color:#6c7867}.notebook label{display:block;font-size:12px;line-height:1.9;color:#566650;margin:10px 0 6px}.frontier textarea{resize:vertical;min-height:84px;width:100%;padding:9px 10px;border:1px solid #ccd5c4;background:#fffefa;font-size:13px;line-height:1.85;color:#344b3d}.frontier textarea[readonly]{background:#f4f6ef;color:#6b7665}.notebook .primary{width:100%;margin-top:10px}.notebook .subtle-button{border:0;text-decoration:underline;text-underline-offset:3px;padding:4px 0;font-size:11px;margin-top:8px}.notebook .feedback{font-size:12px;min-height:22px;line-height:1.8;margin:7px 0;color:#52684c}.notebook .feedback.error{color:#925042}.numeric-answer{display:flex;gap:8px;align-items:center}.numeric-answer input{min-width:0;width:100%;border:1px solid #bdcbb4;background:#fffefa;padding:7px 9px;font-size:14px}.numeric-answer span{font-size:11px;white-space:nowrap;color:#7b8671}.formula{margin:10px 0;overflow-x:auto;font-size:13px;padding:8px 0}.formula .katex-display{margin:0}.snapshot-note{border-left:2px solid #b5c3a7;padding-left:10px;font-size:11px!important}.frontier .small-note{font-size:10px;line-height:1.8;color:#929885}.record-controls{display:flex;justify-content:space-between;gap:15px;flex-wrap:wrap;align-items:center;font-size:11px;color:#798573;padding-top:18px}.record-controls button{font-size:11px;padding:5px 10px}.record-controls>div{display:flex;gap:9px}.learning-details{margin-top:32px;border-top:1px solid #c7d1bc}.learning-details details{border-bottom:1px solid #dce2d4;padding:13px 0}.frontier summary{cursor:pointer;color:#3c604b;font-size:14px;line-height:1.9}.detail-content{max-width:860px;padding:13px 0 4px;font-size:13px;line-height:1.95;color:#68745e}.detail-content p{margin:0 0 12px}.detail-content a{color:#356e70!important}.detail-content ul{padding-left:21px}.detail-content li{margin-bottom:7px}.detail-content .ai-prompt{background:#f3f5ed;border-left:2px solid #bdc9ae;padding:12px 15px;white-space:pre-wrap;font:12px/1.95 TextbookSong,serif;overflow-wrap:anywhere}.extra-controls{margin:13px 0}.extra-controls summary{font-size:12px}.extra-controls label{display:block;font-size:12px;margin:12px 0 5px}.extra-controls .control-row{flex-wrap:wrap}.graph-legend{font-size:11px;color:#7a8574;margin:9px 0}.frontier [hidden]{display:none!important}.frontier .loading{padding:70px 0;text-align:center;color:#7a8574}
@media(max-width:1000px){body.frontier .frontier-page{padding-left:22px;padding-right:22px}.frontier-workspace{grid-template-columns:minmax(0,1fr) 280px;gap:20px}.case-heading h2{font-size:22px!important}.learning-bridge{gap:8px 20px}}
@media(max-width:760px){.frontier-workspace{grid-template-columns:1fr}.case-tabs a{font-size:12px;padding:10px!important}.case-tabs a span{font-size:10px}.frontier-title h1{font-size:27px!important}.frontier-figure svg{min-height:230px}.notebook{max-width:none}.learning-bridge{display:block}.learning-bridge span{margin-top:6px}.case-heading h2{font-size:21px!important}.record-controls{align-items:start}.frontier .book-header nav a:last-child{display:block}}
@media print{.case-tabs,.primary-control,.extra-controls,.record-controls button,.notebook button{display:none!important}.frontier-workspace{grid-template-columns:2fr 1fr}.frontier-page{max-width:none!important;padding:0!important}.frontier textarea{border:0}.learning-details details{break-inside:avoid}.frontier-figure{break-inside:avoid}}

/* Keep the question, first control and prediction action together on classroom screens. */
body.frontier .book-header{min-height:56px}body.frontier .frontier-page{padding-top:19px}.frontier-title{margin-bottom:16px}.frontier-title h1{font-size:28px!important;line-height:1.35;margin:3px 0}.frontier-title>p:last-child{font-size:12px;line-height:1.7}.case-tabs{margin-bottom:17px}.case-tabs a{padding-top:8px;padding-bottom:8px;line-height:1.5;font-size:14px}.case-tabs a span{font-size:10px}.case-heading h2{font-size:23px!important;line-height:1.45;margin:4px 0 10px}.learning-bridge{margin-bottom:14px;font-size:12px;line-height:1.65}.figure-label{padding:5px 0}.primary-control{padding:9px 0 7px}.control-title{font-size:13px;margin-bottom:5px}.control-lock{margin:5px 0 0;font-size:10px}.frontier-figure svg{max-height:310px}.readout-strip{padding:8px 0}.readout-strip strong{font-size:15px}.notebook h3{margin-top:12px}.notebook textarea{min-height:69px}.notebook .stage-label{gap:9px;font-size:10px}.notebook label{font-size:12px}.notebook .feedback{margin:4px 0}.learning-details{margin-top:23px}
@media(min-width:761px) and (max-height:800px){.frontier-title .eyebrow{display:none}.frontier-title>p:last-child{display:none}.frontier-title{margin-bottom:10px}.frontier-title h1{font-size:25px!important}.case-tabs{margin-bottom:12px}.case-heading h2{font-size:21px!important}.learning-bridge{margin-bottom:10px}.frontier-figure svg{max-height:300px}.frontier-figure figcaption{font-size:10px;padding-top:4px;padding-bottom:4px}.notebook textarea{min-height:60px}.notebook label{line-height:1.75}.notebook .primary{margin-top:7px}.notebook h3{font-size:16px!important}}

.frontier-figure svg text{font-size:20px}.frontier-figure svg .small{font-size:16px}.frontier-figure svg .charge{font-size:28px}