:root{--bg:#f4f6fb;--card:#ffffff;--ink:#1f2937;--muted:#6b7280;--line:#e6e9f0;--brand:#3b6ef0;--brand-d:#2a55c8;--ok:#16a34a;--warn:#f59e0b;--bad:#ef4444;--soft:#eef3ff}*{box-sizing:border-box}body{margin:0;font-family:-apple-system,PingFang SC,Microsoft YaHei,Segoe UI,sans-serif;background:var(--bg);color:var(--ink);line-height:1.5}.wrap{max-width:900px;margin:0 auto;padding:20px 16px 60px}h1{font-size:20px;margin:0 0 2px}.sub{color:var(--muted);font-size:13px;margin-bottom:14px}.bar{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin-bottom:14px}.chip{background:var(--card);border:1px solid var(--line);border-radius:999px;padding:6px 12px;font-size:13px;display:flex;gap:6px;align-items:center}.chip b{font-variant-numeric:tabular-nums}.timebox{margin-left:auto;display:flex;gap:6px;align-items:center;background:var(--card);border:1px solid var(--line);border-radius:10px;padding:6px 8px;font-size:13px}.timebox button{font-size:12px;padding:4px 8px;border:1px solid var(--line);background:#fff;border-radius:7px;cursor:pointer}.timebox button:hover{border-color:var(--brand);color:var(--brand)}.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px;margin-bottom:14px}.card h2{font-size:15px;margin:0 0 10px;display:flex;align-items:center;gap:8px}label{display:block;font-size:12px;color:var(--muted);margin:8px 0 4px}input,textarea{width:100%;border:1px solid var(--line);border-radius:9px;padding:9px 11px;font-size:14px;font-family:inherit;background:#fff;color:var(--ink)}textarea{resize:vertical;min-height:54px}input:focus,textarea:focus{outline:none;border-color:var(--brand)}.btn{background:var(--brand);color:#fff;border:none;border-radius:9px;padding:10px 16px;font-size:14px;cursor:pointer;font-weight:600}.btn:hover{background:var(--brand-d)}.btn:disabled{background:#c9d2e8;cursor:not-allowed}.btn.ghost{background:#fff;border:1px solid var(--line);color:var(--ink)}.btn.ghost:hover{border-color:var(--brand);color:var(--brand)}.lock{background:#fff4f4;border:1px solid #f7caca;color:#b91c1c;border-radius:10px;padding:10px 12px;font-size:13px;margin-bottom:12px;display:none}.lock.show{display:block}.list{display:flex;flex-direction:column;gap:8px}.item{border:1px solid var(--line);border-radius:10px;padding:10px 12px;display:flex;align-items:center;gap:12px;background:#fff}.item .t{font-weight:700;font-size:15px}.item .m{color:var(--muted);font-size:13px}.item .meta{margin-left:auto;text-align:right;font-size:12px;color:var(--muted)}.tag{font-size:11px;padding:2px 8px;border-radius:999px;background:var(--soft);color:var(--brand)}.tag.due{background:#fdecec;color:var(--bad)}.tag.mastered{background:#e7f7ee;color:var(--ok)}.empty{color:var(--muted);font-size:13px;padding:10px 2px}.review{display:none}.review.show{display:block}.blank{display:inline-block;min-width:70px;border-bottom:2px dashed var(--brand);color:transparent;-webkit-user-select:none;user-select:none;margin:0 2px}.sentence{font-size:17px;background:#f8fafc;border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:6px 0 12px;line-height:1.7}.ans{display:none;margin-top:10px;padding:12px 14px;background:var(--soft);border-radius:10px}.ans.show{display:block}.ans .word{font-size:18px;font-weight:700}.ans .ph{color:var(--muted);font-size:13px;margin-left:6px}.ans .lbl{font-size:11px;color:var(--brand);font-weight:700;margin-top:8px;display:block}.grade{display:flex;gap:10px;margin-top:14px}.grade button{flex:1;padding:11px;border-radius:10px;border:1px solid var(--line);cursor:pointer;font-size:14px;background:#fff}.grade .g-again{border-color:#f3b4b4;color:#b91c1c}.grade .g-hard{border-color:#f6dca0;color:#b45309}.grade .g-easy{border-color:#a7e0bb;color:#15803d}.grade button:hover{filter:brightness(.97)}.progress{font-size:12px;color:var(--muted);margin-bottom:6px}.done{text-align:center;padding:24px 10px}.done .big{font-size:30px}.tip{background:#fffaf0;border:1px solid #f3e3b3;color:#92670a;border-radius:10px;padding:10px 12px;font-size:12.5px;margin-bottom:14px}.mini{font-size:12px;color:var(--muted);margin-top:8px}.ai-box{margin-top:12px;border:1px dashed var(--brand);border-radius:10px;padding:12px;background:#f7f9ff;font-size:13px;display:none}.ai-box.show{display:block}.ai-box .row2{display:flex;gap:8px}.ai-box .k{color:var(--brand);font-weight:700;min-width:74px}.ai-box .merge{color:var(--ok);font-weight:700;margin-bottom:6px}code{background:#eef1f6;padding:1px 5px;border-radius:5px;font-size:12px}.freq{color:var(--warn);font-weight:700;font-size:12px}.ai-mode{display:flex;flex-wrap:wrap;gap:8px 14px;align-items:center;background:#fff;border:1px solid var(--line);border-radius:10px;padding:10px 12px;margin-bottom:14px;font-size:12.5px}.ai-mode .cb{display:flex;align-items:center;gap:6px;color:var(--ink);white-space:nowrap;cursor:pointer}.ai-mode .cb input{width:auto}.play{border:none;background:transparent;cursor:pointer;font-size:14px;margin-left:6px;padding:0 2px;vertical-align:middle}.del{margin-left:8px;border:1px solid var(--line);background:#fff;color:var(--bad);border-radius:7px;padding:5px 10px;font-size:12px;cursor:pointer;white-space:nowrap}.del:hover{background:#fff4f4;border-color:#f3b4b4}.cc{color:var(--ok);font-weight:700}.toast{position:fixed;left:50%;bottom:24px;transform:translate(-50%);background:var(--ok);color:#fff;padding:10px 16px;border-radius:10px;font-size:13px;box-shadow:0 6px 20px #0000002e;cursor:pointer;z-index:50}.auth-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:20px}.auth-card{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:28px 26px;max-width:380px;width:100%;box-shadow:0 10px 40px #1e325a14}.auth-card h1{font-size:22px;margin:0 0 4px}.auth-card .sub{color:var(--muted);font-size:13px;margin-bottom:18px}.auth-card label{display:block;font-size:12px;color:var(--muted);margin:8px 0 4px}.auth-card input{width:100%;border:1px solid var(--line);border-radius:9px;padding:10px 12px;font-size:14px;font-family:inherit;background:#fff;color:var(--ink)}.auth-card input:focus{outline:none;border-color:var(--brand)}.auth-card .btn{width:100%;margin-top:14px}.auth-card .sent{background:var(--soft);border:1px solid #cfe0ff;border-radius:10px;padding:14px;font-size:13px;line-height:1.7}.auth-card .err{color:var(--bad);font-size:12.5px;margin-top:10px}.topbar{display:flex;align-items:center;gap:10px;margin-bottom:14px;flex-wrap:wrap}.topbar .who{font-size:13px;color:var(--muted)}.topbar .btn.ghost{margin-left:auto;padding:6px 12px;font-size:13px}