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h2{margin:0;font-size:24px}.library-filters{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;padding-bottom:18px;border-bottom:1px solid var(--border);margin-bottom:18px;flex-shrink:0}.library-filters label{display:flex;flex-direction:column;gap:6px;min-width:0;font-size:14px;color:#626b79}.library-filters select{width:100%;min-width:0;padding:9px 8px;background:#fff;border:1px solid var(--border);border-radius:5px;color:#535f74;font-size:16px;cursor:pointer}.lesson-list{min-height:0;overflow:auto;padding:2px 4px 12px}.lesson-section+.lesson-section{margin-top:28px}.lesson-section h3{display:flex;align-items:center;gap:8px;margin:0 0 12px;font-size:17px;font-weight:600}.lesson-section h3 span{color:var(--muted);font-size:14px;font-weight:400}.lesson-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:22px 16px}.library-empty{margin:12px 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small{display:block;font-size:13px;line-height:1.6;color:#626b79}.result>.icon-button{position:absolute;top:4px;right:4px;width:30px;height:30px}.toast{position:fixed;bottom:110px;left:50%;transform:translate(-50%);z-index:100;padding:12px 18px;background:#30343d;color:#fff;border-radius:6px;max-width:calc(100vw - 30px);width:max-content;font-size:16px;box-shadow:0 5px 25px #1f263322}@media(max-width:1250px){.app-dock{grid-template-columns:1fr auto;gap:12px;padding:10px 24px}.tools{grid-column:1 / -1;justify-self:center}.best-score{grid-column:1;grid-row:2}.footer-actions{grid-column:2;grid-row:2}.boards{width:min(100%,max(220px,calc(100dvh - 300px - var(--step-space))))}.copy-mode{width:min(100%,max(440px,calc((100dvh - 320px - var(--step-space)) * 2 + 24px)))}.save-status{display:none}}@media(max-width:700px){.app-header{height:108px;grid-template-columns:1fr auto;gap:10px;padding:12px 16px}.brand{font-size:21px}.mode-tabs{grid-row:2;grid-column:1 / -1;justify-self:stretch}.mode-tabs button{flex:1 1 0;min-width:0;gap:6px;font-size:13px;padding:8px 5px;white-space:nowrap}.header-actions{grid-column:2;grid-row:1}.header-actions .icon-button{width:32px;height:32px;border:0}.practice-controls{flex-wrap:wrap;gap:0 10px;padding:9px 16px}.drawing-picker{gap:7px;padding-right:5px}.current-thumbnail{width:32px;height:32px}.current-thumbnail svg{width:31px;height:31px}#lesson-name{font-size:16px}.difficulty{display:none}.picker-caption{font-size:12px;margin-top:1px}.board-options{flex:1;gap:6px;justify-content:flex-end}.outline-control{gap:5px}.outline-control label{display:none}.outline-control input{width:58px}.outline-control output{display:none}.board-option-actions{gap:3px}.grid-control{gap:5px}.grid-control>span:not(.switch){display:none}.grid-control svg{width:15px;height:15px}.switch{width:24px;height:14px}.switch:after{width:10px;height:10px}.grid-control input:checked+.switch:after{transform:translate(10px)}.text-button{font-size:14px;gap:4px;padding:6px}.text-button svg{width:16px;height:16px}#swap-boards{width:30px;height:34px}.canvas-stage{padding:0 16px 12px;justify-content:flex-start}.canvas-stage.has-steps{--step-space: 110px}.boards{margin-top:auto;margin-bottom:auto;width:min(100%,max(180px,calc(100dvh - 340px - var(--step-space))))}.canvas-stage.has-steps .boards{margin-bottom:0}.copy-mode{width:min(100%,max(180px,calc(100dvh - 480px - var(--step-space))));grid-template-columns:minmax(0,1fr);gap:10px}.reference-pane{width:90px;justify-self:center}.board-label{height:18px;font-size:12px;margin-bottom:4px}.step-panel{display:flex;flex-direction:column;gap:8px;width:min(100%,440px);margin-top:16px;margin-bottom:auto;padding-top:12px;border-top:1px solid var(--border)}.step-top{order:2;min-height:40px}.step-count{color:var(--muted);font-weight:500}.step-panel p{order:1;margin:0;line-height:1.45}.step-actions .icon-button{width:40px;height:40px}.step-play{min-width:40px;width:40px;height:40px;padding:0;background:#dee5fb;color:var(--accent)}.step-play span{display:none}.step-play svg{width:20px;height:20px}.app-dock{grid-template-columns:minmax(0,1fr) auto;gap:10px;padding:10px max(16px,env(safe-area-inset-right)) max(12px,env(safe-area-inset-bottom)) max(16px,env(safe-area-inset-left))}.tools{display:grid;grid-template-columns:auto 1px minmax(0,1fr) 1px auto;gap:6px;padding:6px 10px;width:min(100%,440px);min-width:0}.tools .icon-button{width:30px;height:40px;padding:0}.tool-group{gap:0}.palette{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:0;min-width:0}.swatch{display:grid;place-items:center;width:100%;min-width:0;height:40px;padding:0;border-radius:0;background:transparent;box-shadow:none}.swatch:before{content:"";position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:20px;height:20px;border-radius:50%;background:var(--swatch);box-shadow:inset 0 0 0 1px #ffffff20;pointer-events:none}.swatch[aria-pressed=true]{outline:none}.swatch[aria-pressed=true]:before{outline:2px solid white;outline-offset:1px}.swatch svg{position:relative;width:14px;height:14px}.swatch:focus-visible:before{outline:3px solid #8e9ffc;outline-offset:1px}.best-score{font-size:12px}.best-score svg{width:12px;height:12px}.footer-actions{gap:5px}.primary-button{padding:11px 12px;font-size:14px}.next-button{width:36px;height:36px;padding:8px;justify-content:center}.next-button span{display:none}.next-button svg{width:19px;height:19px}.library{padding:22px;max-height:calc(100dvh - 40px)}.lesson-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:20px 12px}.library-heading h2{font-size:22px}.result[open]{gap:15px}.result{padding:28px 22px}.result-score{min-width:68px}.result-score strong{font-size:36px}}@media(max-width:390px){.tool-group svg{width:18px;height:18px}.outline-control input{width:42px}}@media(max-width:374px){.mode-tabs button{font-size:12px;gap:4px}.library-filters{grid-template-columns:minmax(0,1fr);gap:10px}.canvas-stage.has-steps{--step-space: 140px}.tools{grid-template-columns:auto minmax(0,1fr);gap:4px 10px}.tools .tool-divider{display:none}.tools .tool-group:last-child{grid-column:1 / -1;justify-content:center;border-top:1px solid #505562;padding-top:3px}.tools .icon-button{width:38px;height:34px}.boards{width:min(100%,max(160px,calc(100dvh - 380px - var(--step-space))))}.copy-mode{width:min(100%,max(160px,calc(100dvh - 510px - var(--step-space))))}.lesson-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}