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/* Synchronized classroom laboratory */
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b{background:#1d5e8a;color:white;border-radius:50%;display:grid;place-items:center;flex-shrink:0;width:32px;height:32px;font-size:16px}.algebra-step span{font-size:22px;overflow-wrap:anywhere}.algebra-step.locked{border-style:dashed;background:#f5f7f9;color:#768b93}.algebra-step.locked b{background:#c9d6dc}.algebra-step.locked span{font-size:16px}.formula-practice{border-top:1px solid var(--line);margin-top:24px;padding-top:8px}.number-answer{display:flex;align-items:end;flex-wrap:wrap;gap:12px;margin:16px 0}.number-answer input{background:white;border:1px solid #a8bcc4;border-radius:8px;padding:12px;max-width:100%;width:270px;display:block;margin-top:8px}.number-answer label{flex:1;min-width:220px}.number-answer button{padding:12px 18px}.application-grid{display:grid;grid-template-columns:1.25fr 1fr;gap:24px;align-items:center;margin:22px 0}.application-grid svg{background:#eff4f7;border:1px solid #d7e3e8;border-radius:12px}.application-grid svg 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/* iPad / Apple Pencil annotation controls */
.ink-launch{position:fixed;right:max(22px,env(safe-area-inset-right));bottom:max(22px,env(safe-area-inset-bottom));z-index:120;background:#173b3e;color:white;border:2px solid white;border-radius:28px;box-shadow:0 4px 18px #16373f40;min-height:52px;padding:10px 22px;font-weight:750}.ink-launch:hover{background:#2d6265;color:white}#inkLayer{position:fixed;inset:0;width:100%;height:100%;z-index:90;pointer-events:none;overflow:hidden}#inkLayer.ink-writing{pointer-events:auto;touch-action:none;cursor:crosshair;user-select:none;-webkit-user-select:none;-webkit-touch-callout:none}.ink-toolbar{position:fixed;inset:auto 12px max(8px,env(safe-area-inset-bottom)) 12px;z-index:110;max-width:1260px;margin:auto;padding:12px 16px;background:#f9fcff;border:1px solid #a9c4ce;border-radius:15px;box-shadow:0 0 0 1px #fff,0 6px 32px #0c304140;font-size:15px;color:#173b3e;touch-action:manipulation}.ink-topline{display:flex;align-items:center;gap:14px;margin-bottom:8px}.ink-topline strong{font-size:17px}.ink-topline>span{flex:1;color:#517078;font-size:13px}.ink-topline button{margin-left:auto;min-height:44px}.ink-controls{display:flex;align-items:center;flex-wrap:wrap;gap:8px}.ink-controls button{min-width:44px;min-height:44px;white-space:nowrap;padding:7px 12px;border-color:#c0d2d9;font-size:15px}.ink-tools,.ink-colors{display:flex;gap:4px;align-items:center}.ink-colors button{padding:7px;width:44px;height:44px;border-radius:50%;background:#fff}.ink-colors button span{display:block;width:25px;height:25px;border-radius:50%;background:var(--ink-color);margin:auto}.ink-colors button.selected{border:2px solid #243e43;box-shadow:0 0 0 1px white}.ink-width-label{display:flex;align-items:center;gap:6px;margin:0;font-size:14px}.ink-width-label select{width:68px;margin:0;min-height:44px;padding:7px}.ink-penonly{display:flex;gap:7px;align-items:center;min-height:44px;padding:6px}.ink-penonly input{width:22px;height:22px;accent-color:#1d6258;margin:0}.ink-toolbar p{font-size:13px;color:#496771;margin:8px 0 0;line-height:1.5}.ink-active main{padding-bottom:calc(var(--ink-toolbar-height,170px) + 24px)}#inkBoard{position:fixed;inset:12px 12px calc(var(--ink-toolbar-height,180px) + 28px) 12px;z-index:80;border:2px solid #c4d9e2;border-radius:12px;background-color:#fff;background-image:linear-gradient(#dcebf380 1px,transparent 1px),linear-gradient(90deg,#dcebf380 1px,transparent 1px);background-size:28px 28px;box-shadow:0 0 0 30px #eaf1f7;touch-action:none;overflow:hidden}.ink-board-title{position:absolute;top:10px;left:14px;font-size:14px;color:#64818d;background:#fffffff0;padding:4px 8px;border-radius:5px;pointer-events:none}@media(max-width:700px){.ink-toolbar{left:6px;right:6px;padding:9px 10px;max-height:45vh;overflow:auto}.ink-topline{gap:8px}.ink-topline>span{font-size:12px}.ink-controls{gap:5px}.ink-controls button{font-size:14px;padding:6px 9px}.ink-toolbar p{font-size:12px}.ink-colors{gap:2px}.ink-colors button{width:40px;min-width:40px;height:44px}.ink-launch{right:16px;bottom:16px}#inkBoard{left:6px;right:6px}}@media print{#inkLayer,#inkBoard,.ink-toolbar,.ink-launch{display:none!important}.ink-active main{padding-bottom:0}}