:root{--primary: #4f6ef7;--bg: #f5f6fa;--card: #ffffff;--text: #1f2330;--muted: #6b7280}*{box-sizing:border-box}body{margin:0;font-family:system-ui,-apple-system,PingFang SC,sans-serif;background:var(--bg);color:var(--text)}.app{max-width:560px;margin:0 auto;padding:16px;min-height:100vh}header{display:flex;align-items:center;justify-content:space-between;gap:12px}h1{font-size:20px;margin:0;color:var(--primary)}nav{display:flex;gap:8px}nav button{border:none;background:transparent;padding:8px 12px;border-radius:8px;cursor:pointer;font-size:14px;color:var(--muted)}nav button[data-active=true]{background:var(--card);color:var(--primary);font-weight:600}main{margin-top:16px}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.stats div{background:var(--card);border-radius:12px;padding:14px 8px;text-align:center;font-size:13px;color:var(--muted)}.stats b{display:block;font-size:20px;color:var(--text)}.todo{margin-top:16px;background:var(--card);border-radius:12px;padding:16px}.todo .warn{color:#b45309;font-size:13px}button.primary{width:100%;padding:12px;border:none;border-radius:10px;background:var(--primary);color:#fff;font-size:16px;cursor:pointer;margin-top:12px}.study{text-align:center}.study .hint{color:var(--muted);font-size:13px}.study h2{font-size:34px;margin:24px 0;word-break:break-word}.audio{background:none;border:1px solid var(--primary);color:var(--primary);border-radius:8px;padding:6px 14px;cursor:pointer;margin:6px}.answer{background:var(--card);border-radius:12px;padding:16px;margin-top:12px}.answer .ex{color:var(--muted);font-size:14px}.qualities{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:16px}.qualities button{padding:12px 0;border:none;border-radius:10px;font-size:15px;cursor:pointer;color:#fff}.q-again{background:#ef4444}.q-hard{background:#f59e0b}.q-good{background:#10b981}.q-easy{background:#3b82f6}.lib{list-style:none;padding:0;margin:0}.lib li{background:var(--card);border-radius:10px;padding:12px;margin-bottom:8px;font-size:14px;display:flex;justify-content:space-between;align-items:center;gap:8px}.lib i{color:var(--muted);font-style:normal;font-size:12px}.pill{background:var(--bg);border-radius:999px;padding:2px 10px;font-size:12px;color:var(--muted);white-space:nowrap}.loading{text-align:center;margin-top:40vh;color:var(--muted)}@media(min-width:700px){.app{max-width:720px}.study h2{font-size:44px}}.quiz{text-align:center}.quiz input{width:100%;padding:12px;font-size:18px;border:2px solid var(--primary);border-radius:10px;margin:12px 0;text-align:center}.quiz .ok{color:#10b981}.quiz .bad{color:#ef4444}.choices{display:grid;gap:8px;margin:16px 0}.choices button{padding:14px;border:1px solid var(--muted);background:var(--card);border-radius:10px;font-size:15px;cursor:pointer}.choices button.picked{border-color:var(--primary);background:#eef1ff}.stats-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}.stat-card{background:var(--card);border-radius:12px;padding:16px 8px;text-align:center}.stat-card b{display:block;font-size:24px;color:var(--primary)}.stat-card span{font-size:12px;color:var(--muted)}.muted{color:var(--muted);font-size:13px;text-align:center}.phon{color:var(--muted);font-size:15px;margin:4px 0}.senses{list-style:none;padding:0;text-align:left;margin:8px 0;max-height:40vh;overflow-y:auto}.senses li{padding:4px 0;border-bottom:1px dashed var(--bg);font-size:14px}.senses i{color:var(--primary);font-style:normal;margin-right:6px}.forms{color:var(--muted);font-size:12px;margin:8px 0}.lib-item{align-items:flex-start!important}.lib-main{flex:1;min-width:0}.lib-cn{color:var(--muted);font-size:12px;margin-top:2px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.phon-sm{color:var(--muted);font-size:12px;margin-left:6px}