:root{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--accent:#c8412b;--accent-ink:#a8321f;--accent-soft:#fbedea;--ink:#1a1f2b;--muted:#5b6472;--faint:#9aa1ab;--line:#e3e5e8;--line-strong:#d5d9de;--bg:#f4f5f7;--surface:#fff;--blue:#2f5c9e;--blue-soft:#eaf0f8;--blue-line:#c9d6ea;--warn-bg:#fff7ee;--warn-line:#f0c9a6;--warn-ink:#7a4a12;--ok:#2e8b57;--ok-bg:#eaf5ee;--ok-line:#bfe0cb;--ok-ink:#1f5e3a;--ui:"PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif;--kai:"LXGW WenKai GB", "KaiTi", "STKaiti", serif;--radius:8px}*{box-sizing:border-box}html,body{height:100%;margin:0}body{font-family:var(--ui);color:var(--ink);background:var(--bg);font-size:14px;line-height:1.5}#root{flex-direction:column;min-height:100%;display:flex}a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}button,input,textarea,select{font-family:inherit;font-size:inherit;color:inherit}:focus-visible{outline:2px solid 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8px;font-size:11px;display:inline-flex}.chip-blue{border-color:var(--blue-line);color:var(--blue)}.chip-accent{border-color:var(--accent);color:var(--accent-ink);background:var(--accent-soft)}.chip-warn{border-color:var(--warn-line);color:var(--warn-ink);background:var(--warn-bg)}.notice{border-radius:8px;padding:10px 12px;font-size:13px;line-height:1.6}.notice-warn{background:var(--warn-bg);border:1px solid var(--warn-line);color:var(--warn-ink)}.notice-ok{background:var(--ok-bg);border:1px solid var(--ok-line);color:var(--ok-ink)}.notice-blue{background:var(--blue-soft);border:1px solid var(--blue-line);color:var(--blue)}.notice-info{background:var(--bg);border:1px solid var(--line);color:var(--muted)}.topbar{background:var(--surface);border-bottom:1px solid var(--line);z-index:20;flex-wrap:wrap;flex:none;align-items:center;gap:14px;height:60px;padding:0 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#1a1f2b1f}.word-grid{grid-template-columns:92px minmax(0,1fr) 46px 28px;align-items:center;gap:6px 8px;display:grid}.word-grid .head{color:var(--muted);font-size:12px}.word-text{font-size:15px;font-weight:500}.statline{color:var(--muted);justify-content:space-between;font-size:12px;display:flex}.statline b{color:var(--ink);font-weight:400}.locked{position:relative}.lock-note{color:var(--accent-ink);font-size:11px}.fc-row{border:1px solid var(--line);cursor:pointer;background:#fff;border-radius:8px;grid-template-columns:92px minmax(0,1fr) minmax(0,1fr) 84px 60px;align-items:center;gap:8px;padding:8px 12px;display:grid}.fc-row.selected{border-color:var(--accent)}.fc-sentences{border-top:1px dashed var(--line);flex-wrap:wrap;grid-column:1/-1;align-items:center;gap:6px;padding-top:6px;display:flex}.sent{background:var(--bg);border:1px solid var(--line);border-radius:6px;align-items:center;gap:4px;padding:2px 4px 2px 8px;font-size:12px;display:inline-flex}.sent.ai{background:var(--warn-bg);border-color:var(--warn-line);color:var(--warn-ink)}.flashcard-preview{flex-direction:column;width:300px;height:400px;display:flex}.modal-backdrop{z-index:50;background:#1a1f2b66;justify-content:center;align-items:center;padding:16px;display:flex;position:fixed;inset:0}.modal{background:#fff;border-radius:12px;flex-direction:column;gap:14px;width:100%;max-width:520px;max-height:90vh;padding:22px;display:flex;overflow:auto;box-shadow:0 12px 40px #1a1f2b40}.modal h2{font-family:var(--kai);margin:0;font-size:20px}.toasts{z-index:60;flex-direction:column;gap:8px;display:flex;position:fixed;bottom:20px;left:50%;transform:translate(-50%)}.toast{background:var(--ink);color:#fff;border-radius:8px;max-width:90vw;padding:10px 16px;font-size:13px;box-shadow:0 6px 20px #0003}.toast.error{background:#9b2c1c}.hero{flex-wrap:wrap;align-items:center;gap:48px;padding:48px 0 24px;display:flex}.hero 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var(--line);cursor:pointer;background:#fff;border-radius:12px;align-items:center;gap:12px;width:100%;padding:12px 14px;display:flex}.skill:hover{border-color:var(--line-strong)}.skill-badge{width:44px;height:44px;font:700 18px var(--kai);border-radius:10px;flex:none;justify-content:center;align-items:center;display:inline-flex}.flashcard{cursor:pointer;perspective:1000px;background:0 0;border:none;flex:auto;min-height:320px;padding:0}.flashcard-face{border-radius:16px;flex-direction:column;justify-content:center;align-items:center;gap:12px;height:100%;min-height:320px;padding:24px;display:flex;position:relative}.flashcard-front{border:1px solid var(--line);background:#fff;box-shadow:0 6px 24px #1a1f2b14}.flashcard-back{background:var(--ink);color:#fff}.round-btn{border:1px solid var(--line-strong);cursor:pointer;background:#fff;border-radius:26px;flex:none;justify-content:center;align-items:center;width:52px;height:52px;display:inline-flex}.pill-btn{cursor:pointer;border:none;border-radius:26px;justify-content:center;align-items:center;gap:8px;height:52px;padding:0 20px;font-size:15px;font-weight:500;display:inline-flex}.option-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;display:grid}.option{border:1px solid var(--line-strong);cursor:pointer;min-height:72px;font-family:var(--kai);background:#fff;border-radius:12px;padding:6px;font-size:28px}.option.right{border:2px solid var(--ok);background:var(--ok-bg);color:var(--ok-ink)}.option.wrong{background:var(--warn-bg);color:var(--warn-ink);border:2px solid #c97a1e}.option.selected{border:2px solid var(--accent);background:var(--accent-soft);color:var(--accent-ink)}.option.small{font-family:var(--ui);font-size:16px}.option.hidden{visibility:hidden}.progress{background:var(--line);border-radius:3px;height:6px;overflow:hidden}.progress>div{background:var(--accent);border-radius:3px;height:100%;transition:width .2s}.writer-row{justify-content:center;display:flex}.writer-cell{border:2px solid var(--accent);background:#fff;margin-left:-2px;position:relative}.writer-cell:first-child{margin-left:0}@media (width<=1100px){.editor{flex-direction:column}.panel-left,.panel-right{border:none;border-bottom:1px solid var(--line);flex:none}.preview-scroll{height:auto;min-height:60vh;overflow:visible}}@media (width>=760px){.practice{border-left:1px solid var(--line);border-right:1px solid var(--line);max-width:760px}.practice-header{height:64px;padding:0 24px}.practice-body{gap:18px;padding:24px 32px 32px}.skill-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.kbd-hint{display:inline}.flashcard,.flashcard-face{min-height:420px}.option{min-height:92px;font-size:34px}.option.small{font-size:18px}.option-grid.match{grid-template-columns:repeat(var(--cols,5), minmax(0, 1fr))}.option-grid.match .option{min-height:110px}.pill-btn{height:48px}}@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}