.stem-lab{overflow-anchor:none;margin:24px 0;padding:28px;border:1px solid #bfd4ca;border-radius:22px;background:#f0f6f2;color:#294539}.stem-lab h2{margin:12px 0}.stem-lab p{line-height:1.6}.stem-scope{padding-left:12px;border-left:3px solid #86a898;color:#506d5e}.stem-key{display:flex;gap:12px 24px;align-items:center;flex-wrap:wrap;padding:18px 22px;background:#dfede5;border-radius:14px;margin:24px 0}.stem-key>span{font-size:1rem;letter-spacing:.08em;font-weight:700}.stem-key strong{font-size:28px}.stem-key p{margin:0}.stem-actions,.stem-presets{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin:20px 0}.stem-lab button{min-height:48px;white-space:normal}.stem-lab button:disabled{opacity:.42;cursor:default}.stem-mode{font-weight:700;color:#416b56}.stem-cards{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:12px;margin:22px 0}.stem-cards button{padding:12px 8px;display:flex;flex-direction:column;align-items:center;gap:6px;border:2px solid #b5ccbe;border-radius:12px;background:white;color:#294539;font:inherit;min-width:0;touch-action:none;cursor:grab}.stem-cards button:active,.stem-leaves button:active{cursor:grabbing}.stem-cards strong{font-size:32px}.stem-cards i{overflow-wrap:anywhere;font-style:normal;color:#526e5f;font-size:1rem;margin-top:4px}.stem-cards small{font-size:1rem}.stem-cards button[aria-pressed=true],.stem-leaves button[aria-pressed=true]{border-color:#a96528;background:#fff1df;box-shadow:0 0 0 2px #ddbb92}.stem-notice{padding:16px;background:white;border-left:4px solid #88ab96}.stem-workbench{display:grid;grid-template-columns:minmax(0,1.8fr) minmax(260px,1fr);gap:20px;margin:24px 0;align-items:start}.stem-board,.stem-summary{min-width:0;padding:20px;background:white;border:1px solid #bcd2c5;border-radius:16px}.stem-table-head{display:grid;grid-template-columns:76px 1fr;gap:14px;padding:0 0 12px;color:#526e5f;font-weight:700}.stem-row{display:grid;grid-template-columns:76px minmax(0,1fr);gap:14px;min-height:86px;border-top:1px solid #dce7e0;padding:8px 0;align-items:stretch;transition:background-color .12s}.stem-root{font-size:30px;font-weight:800;border:1px solid #b9cebf;border-radius:10px;background:#e9f2ec;color:#355d44}.stem-root b{font-size:30px;line-height:1.1}.stem-leaves{display:flex;flex-wrap:wrap;gap:10px;align-items:center;padding:4px 0 4px 14px;border-left:3px solid #85a892;min-width:0}.stem-leaves button{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;border:2px solid #c3d6ca;background:#f3f8f4;color:#294539;border-radius:10px;padding:6px 10px;min-width:64px;touch-action:none;cursor:grab}.stem-leaves b{font-size:28px;line-height:1.1}.stem-leaves small{font-size:1rem;white-space:nowrap}.stem-leaves .stem-wrong{border:3px dashed #ac493c;background:#fff0ec}.stem-empty{color:#647e6d;font-style:italic;padding:12px}.stem-drop-target{background:#dcefe0;outline:3px dashed #4c845b;outline-offset:3px;border-radius:10px}.stem-drag-ghost{position:fixed;z-index:20000;pointer-events:none;background:#285c42;color:white;padding:12px 18px;border-radius:10px;font-size:22px;box-shadow:0 5px 15px #203c4a40}.stem-metrics{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.stem-metrics>div{background:#e8f3eb;border:1px solid #bfd6c6;padding:12px;border-radius:10px}.stem-metrics strong{display:block;font-size:30px;margin-top:8px}.stem-equation{display:flex;align-items:center;flex-wrap:wrap;gap:12px;font-size:30px;padding:16px;border-radius:12px;background:#fff0df;color:#795023}.stem-zero-note{border-left:4px solid #70997f;padding:12px;background:#eef6f0}.stem-builder,.stem-data-editor{padding:20px;border:1px solid #bed3c5;border-radius:16px;background:white;margin:24px 0}.stem-builder-controls{display:flex;flex-wrap:wrap;gap:16px;align-items:end}.stem-builder-controls label{font-weight:650}.stem-lab select{font:inherit;display:block;min-width:100px;padding:12px;margin-top:10px;border:1px solid #a9c4b2;border-radius:8px;background:white;color:#294539}.stem-data-editor label{display:block;font-weight:650}.stem-data-editor input[type=range]{display:block;width:100%;height:44px;margin:16px 0}.stem-lab fieldset{min-width:0;margin:24px 0;padding:20px;border:1px solid #b8d0c0;border-radius:14px}.stem-lab legend{font-size:1.15rem;font-weight:750;padding:0 8px}.stem-lab input[type=text]{display:block;max-width:260px;width:100%;font:inherit;padding:12px;margin:12px 0 18px;border:1px solid #a7c3b1;border-radius:8px;background:white}.stem-feedback{padding:16px;background:#f1f7f3;border-left:4px solid #5d896d}.stem-reason{display:block;font-weight:650;margin:24px 0}.stem-reason textarea{font:inherit;font-weight:400;width:100%;max-width:100%;min-height:110px;display:block;padding:12px;margin-top:12px;border:1px solid #abc5b5;border-radius:10px;background:white}.stem-teacher{padding:18px;background:white;border:1px solid #bed3c5;border-radius:12px;margin:24px 0}.stem-teacher summary{cursor:pointer;font-weight:650}.stem-teacher li{margin:12px 0}.stem-lab>small{display:block;font-size:1rem;color:#506d5e}.stem-lab :is(button,input,select,textarea,summary):focus-visible{outline:3px solid #a96528;outline-offset:3px}
@media(max-width:1050px){.stem-workbench{grid-template-columns:1fr}.stem-cards{grid-template-columns:repeat(4,minmax(0,1fr))}}
@media(max-width:650px){.stem-lab{padding:14px}.stem-board,.stem-summary,.stem-builder,.stem-data-editor,.stem-lab fieldset{padding:12px}.stem-cards{grid-template-columns:repeat(2,minmax(0,1fr))}.stem-row,.stem-table-head{grid-template-columns:52px minmax(0,1fr);gap:10px}.stem-leaves{padding-left:10px;gap:8px}.stem-leaves button{min-width:62px;padding:6px}.stem-root{font-size:28px}.stem-actions,.stem-presets{display:grid}.stem-lab legend{font-size:1.1rem}.stem-metrics{grid-template-columns:1fr}.stem-key{padding:14px}.stem-key strong{font-size:26px}.stem-builder-controls{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.stem-builder-controls button{grid-column:1/-1}.stem-lab select{width:100%;min-width:0}}
@media print{.stem-actions,.stem-presets,.stem-builder,.stem-data-editor,.stem-lab fieldset button{display:none}.stem-workbench{grid-template-columns:1fr}.stem-cards{grid-template-columns:repeat(4,minmax(0,1fr))}}