:root{color:#1f2937;background:#f5f2ea;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh}button{color:inherit;font:inherit}.app-shell{display:grid;grid-template-columns:minmax(240px,300px) 1fr;min-height:100vh}.lesson-list{display:flex;flex-direction:column;gap:28px;padding:32px;background:#243b53;color:#f8fafc}.eyebrow{margin:0 0 8px;color:#d49b54;font-size:.8rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase}h1,h2,p{margin-top:0}h1{margin-bottom:0;font-size:clamp(1.8rem,3vw,2.6rem);line-height:1.05}h2{margin-bottom:10px;font-size:1.4rem}.character-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.page-nav{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.page-nav button{min-height:44px;border:1px solid rgba(255,255,255,.24);border-radius:8px;background:#ffffff1f;color:#fff;cursor:pointer;font-weight:900}.page-nav button.active{border-color:#e9b872;background:#e9b872;color:#1f2937}.lesson-selector{display:grid;gap:8px}.lesson-selector span{color:#d49b54;font-size:.8rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase}.lesson-selector select{width:100%;min-height:46px;border:1px solid rgba(255,255,255,.24);border-radius:8px;background:#fff;color:#1f2937;font:inherit;font-weight:800}.character-tile,.quiz-choice,.icon-button{border:0;cursor:pointer}.character-tile{aspect-ratio:1;border-radius:8px;background:#ffffff1f;color:#fff;font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:3rem;transition:transform .16s ease,background .16s ease}.character-tile:hover,.character-tile.active{background:#e9b872;color:#1f2937;transform:translateY(-2px)}.study-area{display:grid;grid-template-rows:auto auto minmax(460px,1fr) auto;gap:20px;padding:28px}.reading-area{display:grid;align-content:start;gap:20px;padding:28px}.reading-page-heading h2{margin-bottom:0}.top-bar{display:flex;align-items:center;justify-content:flex-end;gap:14px;color:#52616f;font-weight:800}.icon-button{display:inline-flex;align-items:center;justify-content:center;width:48px;height:48px;border-radius:8px;background:#fff;box-shadow:0 8px 22px #1f293714}.icon-button.active{background:#e9b872;color:#1f2937;box-shadow:0 10px 24px #9b4d2d2e}.learning-card{display:grid;grid-template-columns:minmax(210px,280px) 1fr;gap:28px;align-items:center}.character-display{display:grid;place-items:center;aspect-ratio:1;border:1px solid #ddcab2;border-radius:8px;background:#fffaf1;color:#17202a;font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:clamp(8rem,18vw,13rem);line-height:1}.character-details{max-width:520px}.sound{margin-bottom:6px;color:#2f80a3;font-size:2rem;font-weight:900}.example-list{display:grid;gap:10px;margin-top:20px}.example-item{display:grid;grid-template-columns:minmax(82px,auto) 1fr;gap:14px;align-items:center}.example-word{margin:0;color:#243b53;font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:2.1rem;font-weight:800;line-height:1}.word-sound{margin-bottom:2px;color:#52616f;font-size:1.1rem;font-weight:800}.word-meaning{margin-bottom:0;color:#52616f}.practice-stack{display:grid;gap:14px}.practice-panel{position:relative;overflow:hidden;height:clamp(420px,52vh,560px);min-height:460px;border:1px solid #d8c9b7;border-radius:8px;background:linear-gradient(to right,transparent 49.8%,rgba(36,59,83,.18) 50%,transparent 50.2%),linear-gradient(to bottom,transparent 49.8%,rgba(36,59,83,.18) 50%,transparent 50.2%),#fffdf8;touch-action:none}.stroke-writer-target{position:absolute;top:0;right:0;bottom:0;left:0;z-index:1}.free-practice-canvas{position:absolute;top:0;right:0;bottom:0;left:0;z-index:3;width:100%;height:100%;pointer-events:none;touch-action:none}.free-practice-active .free-practice-canvas{pointer-events:auto}.free-practice-canvas polyline{fill:none;stroke:#243b53;stroke-linecap:round;stroke-linejoin:round;stroke-width:24}.practice-toolbar{position:absolute;top:16px;right:16px;z-index:4;display:flex;gap:10px}.practice-status{position:absolute;left:18px;bottom:14px;z-index:4;margin:0;color:#52616f;font-size:.95rem;font-weight:800}.mini-stroke-row{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));grid-auto-rows:1fr;gap:12px}.mini-stroke-writer{position:relative;overflow:hidden;aspect-ratio:1;min-width:0;border:1px solid #d8c9b7;border-radius:8px;background:linear-gradient(to right,transparent 49.5%,rgba(36,59,83,.12) 50%,transparent 50.5%),linear-gradient(to bottom,transparent 49.5%,rgba(36,59,83,.12) 50%,transparent 50.5%),#fffdf8;touch-action:none}.mini-stroke-writer svg{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%}.reading-panel{position:relative;isolation:isolate;overflow:hidden;display:grid;gap:18px;padding:22px;border:1px solid #d8c9b7;border-radius:8px;background:#fff;box-shadow:0 10px 28px #1f29370f}.reading-panel.with-background:before{position:absolute;top:0;right:0;bottom:0;left:0;z-index:-1;background-image:var(--reading-image);background-position:center;background-repeat:no-repeat;background-size:cover;content:"";opacity:.18}.reading-header{display:grid;gap:20px;align-items:end}.reading-header h2{margin-bottom:0}.reading-content{display:flow-root}.reading-line{display:flex;flex-wrap:wrap;gap:10px 8px;align-items:flex-end}.reading-line-break{flex-basis:100%;height:0}.reading-token{display:grid;min-width:58px;min-height:76px;padding:8px 8px 7px;border:2px solid #d8c9b7;border-radius:8px;background:#fffaf1;color:#1f2937;cursor:pointer;text-align:center}.reading-token.active{border-color:#9b4d2d;background:#e9b872}.reading-character{font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:2.25rem;font-weight:800;line-height:1}.reading-yale{color:#2f80a3;font-size:.95rem;font-weight:900;line-height:1.15}.reading-punctuation{padding-bottom:18px;color:#52616f;font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:2.25rem;font-weight:800}.reading-meaning{min-height:24px;margin:0;color:#52616f;font-weight:800}.quiz-panel{display:grid;grid-template-columns:1fr auto;gap:20px;align-items:center;padding:20px;border-radius:8px;background:#fff;box-shadow:0 10px 28px #1f293714}.quiz-panel h2{margin-bottom:0}.quiz-options{display:grid;grid-template-columns:repeat(4,74px);gap:10px}.quiz-choice{display:flex;align-items:center;justify-content:center;gap:4px;height:74px;border:2px solid #d8c9b7;border-radius:8px;background:#fffaf1;font-family:PingFang TC,Noto Sans TC,Microsoft JhengHei,serif;font-size:2.4rem;font-weight:800}.quiz-choice.selected{border-color:#9b4d2d}.quiz-choice.correct{background:#e4f3de;border-color:#5b8f4d}@media (max-width: 820px){.app-shell{grid-template-columns:1fr}.lesson-list{padding:20px}.character-grid{grid-template-columns:repeat(5,minmax(54px,1fr))}.character-tile{font-size:2rem}.study-area{padding:20px;grid-template-rows:auto auto minmax(420px,1fr) auto}.practice-panel{height:420px;min-height:420px}.quiz-panel{grid-template-columns:1fr}.reading-panel.with-background:before{opacity:.12}.learning-card{grid-template-columns:220px 1fr;gap:20px}.character-display{width:min(100%,220px);font-size:7rem}.quiz-options{grid-template-columns:repeat(4,minmax(0,1fr))}}@media (max-width: 560px){.learning-card{grid-template-columns:1fr}}