:root{--ink:#18343a;--teal:#1c5d5f;--paper:#fffdf7;--sun:#f6c453;--soft:#e9f4ee;--line:#cddbd5;--rose:#e97e86}*{box-sizing:border-box}body{margin:0;background:#f4f0e6;color:var(--ink);font:17px/1.45 system-ui,-apple-system,"Segoe UI",sans-serif}button{font:inherit;border:0;border-radius:14px;padding:12px 16px;background:var(--teal);color:#fff;font-weight:700;cursor:pointer;min-height:46px}button.ghost{background:#e1ece8;color:var(--ink)}button.warn{background:#fff0f0;color:#7b252b}#app{max-width:900px;margin:auto;padding:18px 16px 92px}.top{display:flex;justify-content:space-between;align-items:center;gap:12px}.brand{font-weight:800;font-size:1.15rem}.sub{font-size:.85rem;color:#52686a}.card{background:var(--paper);box-shadow:0 3px 16px #17302912;border-radius:20px;padding:20px;margin:16px 0}.badge{display:inline-block;background:#fff0c6;color:#735300;border-radius:999px;padding:4px 10px;font-weight:700;font-size:.82rem}.next{border-left:5px solid var(--sun)}h1{font-size:clamp(1.55rem,4vw,2.2rem);line-height:1.15;margin:12px 0}h2{font-size:1.25rem;margin:0 0 10px}.row{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.spaced{justify-content:space-between}.nav{position:fixed;bottom:0;left:0;right:0;background:#fffdf7;border-top:1px solid var(--line);display:flex;justify-content:center;gap:5px;padding:8px env(safe-area-inset-right) calc(8px + env(safe-area-inset-bottom)) env(safe-area-inset-left);z-index:2}.nav button{background:transparent;color:#506265;padding:8px 13px;min-height:42px;font-size:.85rem}.nav button.active{color:var(--teal);background:#e5f1eb}.big{font-size:1.18rem;padding:15px 22px}.progress{height:10px;border-radius:9px;background:#e5ece8;overflow:hidden}.progress i{display:block;height:100%;background:linear-gradient(90deg,var(--sun),#ed9f55)}.meaning{text-align:center;font-size:1.1rem}.canvas-wrap{background:#fbfcfa;border:2px solid #b7cec4;border-radius:16px;overflow:hidden;touch-action:none;position:relative}.grid{background-image:linear-gradient(#d9e6df 1px,transparent 1px),linear-gradient(90deg,#d9e6df 1px,transparent 1px);background-size:50% 50%;background-position:center}canvas{display:block;width:100%;height:min(54vw,400px);touch-action:none}.hint{background:#eef6f3;border-radius:12px;padding:10px 12px;font-size:.94rem}.answer{font-size:1.35rem;font-weight:800;letter-spacing:.04em;padding:12px;background:#fff8e7;border-radius:12px}.small{font-size:.88rem}.stats{display:grid;grid-template-columns:repeat(3,1fr);gap:9px}.stat{background:#edf5f1;border-radius:14px;padding:12px;text-align:center}.stat strong{display:block;font-size:1.35rem}.list{padding:0;list-style:none}.list li{padding:10px 0;border-bottom:1px solid var(--line)}.field{width:100%;font:inherit;padding:14px;border:2px solid #bdcec8;border-radius:13px}.note{color:#52686a;font-size:.92rem}.example-box{margin-top:18px;background:#fdf2dc;border-radius:14px;padding:13px}.example-box p{margin:7px 0 11px}.copybook{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:10px}.copy-cell{position:relative;min-height:154px;border:1px solid #bdd1c6;border-radius:12px;overflow:hidden;display:grid;place-items:center;background-image:linear-gradient(#dce8e2 1px,transparent 1px),linear-gradient(90deg,#dce8e2 1px,transparent 1px);background-size:50% 50%;background-position:center}.copy-cell:before,.copy-cell:after{content:"";position:absolute;background:#dce8e2}.copy-cell:before{height:1px;width:100%;top:50%}.copy-cell:after{width:1px;height:100%;left:50%}.copy-model{position:relative;z-index:1;font-family:"KaiTi","STKaiti",serif;font-size:clamp(3rem,10vw,6rem);font-weight:700;color:#284b4c;letter-spacing:.08em}.copy-model.light{color:#aebdb7;opacity:.7}.copy-model.hidden{visibility:hidden}.copy-label{position:absolute;left:8px;bottom:6px;font-size:.78rem;color:#5d7770;background:#fffdf7cc;padding:2px 5px;border-radius:5px;z-index:1}@media (min-width:700px){#app{padding-top:26px}.practice-layout{display:grid;grid-template-columns:1fr 1.25fr;gap:20px;align-items:start}canvas{height:390px}}