/* Shared classroom experiments: text stays in HTML; animated diagrams use bounded canvases. */
.brand{letter-spacing:0;font-size:21px;white-space:nowrap}.brand strong{font-weight:800}.brand b{font-weight:400}.brand small{letter-spacing:.3px;font-size:11px}.brand-mark{background:none;border-radius:0;width:49px;height:49px}.brand-mark img{display:block;width:100%;height:100%;object-fit:contain}.header{gap:18px}.header nav{gap:5px}.site-footer b{font-weight:800}
.lesson-intro{display:flex;gap:24px;justify-content:space-between;align-items:center;margin-bottom:24px}.lesson-intro p{max-width:760px;font-size:14px;color:#5e776e}.lesson-intro .eyebrow{color:#326d77;font-size:11px}.lesson-badge{border:1px solid #c7ddd5;padding:13px 18px;border-radius:10px;min-width:155px;color:#36715f;font-size:12px;background:#edf5ed;white-space:nowrap}.lesson-badge strong{display:block;font-size:19px;font-weight:700}
.lesson-tabs{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));gap:7px;padding:7px;border:1px solid #dce6dc;background:#eaf0e7;border-radius:12px;margin:0 0 26px}.lesson-tabs button{display:flex;align-items:center;justify-content:center;gap:8px;border-radius:7px;min-height:52px;padding:10px 8px;font-size:13px;font-weight:650;color:#647c70;line-height:1.35}.lesson-tabs button span{font-size:11px;opacity:.7;font-variant-numeric:tabular-nums}.lesson-tabs button[aria-selected=true]{background:#fff;color:#19685c;box-shadow:0 2px 7px #2a5a3a12}.lesson-tabs button:hover{background:#f5f9f1}.lesson-panel{min-height:300px;outline-offset:5px}.lesson-panel[aria-busy=true]{padding:40px;background:#fff;border-radius:12px}
.experiment-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:20px;margin:0 0 20px}.experiment-heading h2{font-size:25px;margin:7px 0 9px;color:#234f49}.experiment-heading p{font-size:14px;color:#638076;max-width:760px;margin:0}.experiment-heading .eyebrow{font-size:11px;color:#5e877d}.experiment-chip{white-space:nowrap;font-size:12px;background:#e7f0eb;border:1px solid #d4e5dc;border-radius:30px;color:#507866;padding:7px 13px;margin-top:12px}
.experiment-layout{display:grid;grid-template-columns:minmax(0,1fr) 305px;gap:22px;align-items:start}.experiment-stage{border:1px solid #d6e4df;background:#fff;border-radius:13px;overflow:hidden;min-width:0}.experiment-stagebar{display:flex;justify-content:space-between;align-items:center;padding:12px 18px;gap:12px;font-size:12px;color:#53766d;background:#f8fbf7;border-bottom:1px solid #dae8e0}.experiment-stagebar button{font-size:12px;min-height:36px;padding:6px 10px}.experiment-canvas{display:block;width:100%;height:auto;aspect-ratio:760/480;background:#e9f4f5}.experiment-legend{display:flex;flex-wrap:wrap;gap:8px 20px;padding:14px 19px;color:#58756c;font-size:12px}.experiment-legend span{display:flex;align-items:center;gap:7px}.experiment-legend i{display:inline-block;width:16px;height:4px;border-radius:2px}.experiment-caption{font-size:12px;line-height:1.7;color:#789086;margin:0;padding:0 19px 16px}
.experiment-controls{border:1px solid #dce6dc;background:#fff;border-radius:13px;padding:23px}.experiment-controls h3{font-size:16px;margin:0 0 17px}.experiment-controls>label{display:block;font-size:13px;font-weight:600;color:#405f53;margin:18px 0 0;position:relative}.experiment-controls label output{float:right;color:#166e68;font-weight:650;font-variant-numeric:tabular-nums}.experiment-controls input[type=range]{height:6px;margin:16px 0 12px}.experiment-controls select,.experiment-controls input[type=number]{display:block;width:100%;padding:10px 11px;margin-top:7px;background:#f7faf4;border:1px solid #cbdcd0;border-radius:6px;font-size:14px;color:#315d4e;min-height:43px}.experiment-controls select:focus{outline-offset:2px}.experiment-controls .experiment-hint{font-size:12px;color:#748b7c;line-height:1.8;margin:10px 0 0}.experiment-range-label{display:flex;justify-content:space-between;color:#889a8e;font-size:12px}.experiment-presets{display:flex;flex-direction:column;gap:8px;margin-top:18px}.experiment-presets button{min-height:40px;font-size:12px}
.experiment-readouts{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:1px;background:#dbe6dd;border:1px solid #dbe6dd;border-radius:11px;overflow:hidden;margin:21px 0 14px}.experiment-readouts>div{background:#fff;padding:18px 20px;min-width:0}.experiment-readouts span{font-size:12px;color:#698578}.experiment-readouts strong{display:block;font-size:20px;color:#246c61;font-weight:650;margin-top:6px;font-variant-numeric:tabular-nums;line-height:1.5}.experiment-insight{background:#e9f2e5;border-left:3px solid #609e74;border-radius:0 7px 7px 0;padding:15px 18px;font-size:14px;color:#436b4e;line-height:1.8;margin:0 0 25px}.experiment-explain{background:#fff;border:1px solid #dce6dc;border-radius:11px;padding:23px;margin:24px 0}.experiment-explain h3{font-size:17px}.mechanism-tabs{display:flex;flex-wrap:wrap;gap:8px;margin:17px 0}.mechanism-tabs button{font-size:13px;padding:9px 13px;border-radius:6px;min-height:40px;background:#f1f5ed;border:1px solid #dce6d8}.mechanism-tabs button[aria-pressed=true]{background:#286e62;color:white;border-color:#286e62}.experiment-explain p{font-size:14px;line-height:1.9;margin:0;color:#637d70}.experiment-lessons{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px;margin:24px 0}.experiment-lessons article{background:#fff;border:1px solid #e0e8db;border-radius:10px;padding:23px}.experiment-lessons b{font-size:14px;font-weight:650;color:#315f50}.experiment-lessons p{font-size:13px;line-height:1.9;margin:12px 0 0;color:#6c8375}.experiment-scope{border-top:1px solid #d5e3d6;padding:17px 0;color:#6d8377;font-size:13px}.experiment-scope summary{cursor:pointer;min-height:40px;font-size:14px;color:#3f6c57}.experiment-scope p{font-size:13px;line-height:1.9;margin:0 0 12px}.experiment-scope a{font-size:13px}
.lesson-source-note{margin:28px 0 16px;padding:18px 21px;border:1px solid #dce5d8;border-radius:9px;font-size:12px;color:#7b8c7e}.lesson-source-note p{margin:0;color:inherit}.lesson-source-note details{margin-top:8px}.lesson-source-note summary{cursor:pointer;min-height:32px;color:#547662}.lesson-source-note li{margin:6px 0}.lesson-panel .sources p{font-size:13px}
@media(max-width:1100px){.brand{font-size:18px}.brand small{font-size:10px}.header{padding-left:24px;padding-right:24px}.nav-button{font-size:12px;padding-left:7px;padding-right:7px}.lesson-tabs{grid-template-columns:repeat(4,1fr)}.experiment-layout{grid-template-columns:minmax(0,1fr) 280px}.experiment-stagebar{align-items:flex-start;flex-wrap:wrap}.experiment-readouts strong{font-size:18px}.experiment-controls{padding:18px}.experiment-chip{display:none}}
@media(max-width:850px){.header{height:auto;flex-wrap:wrap;padding-top:12px}.header nav{order:3;width:100%;justify-content:center;height:48px}.brand{font-size:20px}.lesson-intro{align-items:flex-start}.lesson-badge{display:none}.experiment-layout{grid-template-columns:1fr}.experiment-controls{display:grid;grid-template-columns:1fr 1fr;gap:10px 22px}.experiment-controls>h3,.experiment-controls>.experiment-hint,.experiment-controls>.experiment-presets{grid-column:1/-1}.experiment-controls>label{margin-top:8px}.experiment-controls>.experiment-range-label{display:none}.experiment-presets{flex-direction:row;flex-wrap:wrap;margin-top:8px}.experiment-presets button{flex:1;min-width:170px}.experiment-readouts{grid-template-columns:repeat(2,1fr)}.experiment-lessons{grid-template-columns:1fr}.lesson-intro h1{font-size:25px}.experiment-heading h2{font-size:23px}.experiment-legend{gap:8px 13px}}
@media(max-width:560px){.brand{font-size:19px}.brand-mark{width:40px;height:40px}.brand small{font-size:10px}.header{padding:8px 16px 0}.lesson-tabs{grid-template-columns:repeat(2,minmax(0,1fr));gap:4px;margin-bottom:21px}.lesson-tabs button{font-size:13px;min-height:44px;justify-content:flex-start;padding-left:14px}.lesson-tabs button:last-child{grid-column:1/-1}.lesson-intro p{font-size:13px}.experiment-controls{grid-template-columns:1fr}.experiment-controls>*{grid-column:1!important}.experiment-controls>.experiment-range-label{display:flex}.experiment-heading h2{font-size:21px}.experiment-stagebar{padding:10px 13px}.experiment-readouts>div{padding:14px}.experiment-readouts strong{font-size:16px}.experiment-readouts span{font-size:12px}.experiment-insight{font-size:13px}.experiment-explain{padding:18px}.experiment-canvas{min-height:260px;object-fit:contain}.experiment-chip{display:none}}