:root{--bg: #f4f5fb;--card: #ffffff;--text: #1c1e27;--muted: #6b7280;--primary: #4f46e5;--primary-weak: #eef0fe;--border: #e5e7f0;--danger: #e11d48;--danger-weak: #ffe4ea;--warn: #d97706;--warn-weak: #fdf0d5;--ok: #059669;--ok-weak: #d9f3e7;--radius: 16px;--shadow: 0 1px 3px rgba(28, 30, 39, .08)}@media (prefers-color-scheme: dark){:root{--bg: #12141a;--card: #1c1f26;--text: #e8eaf2;--muted: #9aa1af;--primary: #818cf8;--primary-weak: #272b41;--border: #2a2e3a;--danger: #fb7185;--danger-weak: #3c1d29;--warn: #fbbf24;--warn-weak: #3a2f1a;--ok: #34d399;--ok-weak: #17352b;--shadow: none}}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Microsoft YaHei,Noto Sans SC,sans-serif;background:var(--bg);color:var(--text);font-size:16px;line-height:1.5}button{font:inherit;color:inherit;background:none;border:none;padding:0;cursor:pointer}input,textarea,select{font:inherit;color:inherit}.boot{display:grid;place-items:center;min-height:100dvh;color:var(--muted)}.app{max-width:520px;margin:0 auto;padding:0 16px calc(78px + env(safe-area-inset-bottom))}.page{padding-top:14px}.page-title{font-size:22px;font-weight:700;margin:6px 0 4px}.subtitle{color:var(--muted);font-size:13px;margin:0 0 16px}.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:16px;box-shadow:var(--shadow);margin-bottom:12px}.tabbar{position:fixed;bottom:0;left:50%;transform:translate(-50%);width:100%;max-width:520px;display:flex;background:var(--card);border-top:1px solid var(--border);padding-bottom:env(safe-area-inset-bottom);z-index:40}.tab{flex:1;display:flex;flex-direction:column;align-items:center;gap:2px;padding:8px 0 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var(--border);border-radius:var(--radius);padding:14px 16px;box-shadow:var(--shadow)}.stat .num{font-size:26px;font-weight:700;line-height:1.2}.stat .lbl{font-size:12px;color:var(--muted);margin-top:2px}.bars{display:flex;align-items:flex-end;gap:8px;height:130px;padding-top:10px}.bar-col{flex:1;display:flex;flex-direction:column;align-items:center;gap:5px;height:100%;justify-content:flex-end}.bar{width:100%;max-width:30px;background:var(--primary);border-radius:6px 6px 2px 2px;min-height:3px}.bar-num,.bar-lbl{font-size:11px;color:var(--muted)}.bar-num{color:var(--text);font-weight:600}.progress{height:6px;background:var(--primary-weak);border-radius:3px;overflow:hidden;flex:1}.progress>div{height:100%;background:var(--primary);border-radius:3px;transition:width .25s}.search-wrap{position:relative;margin-bottom:10px}.search{width:100%;padding:11px 14px 11px 40px;border-radius:12px;border:1px solid var(--border);background:var(--card);color:var(--text);outline:none}.search:focus{border-color:var(--primary)}.search-icon{position:absolute;left:13px;top:50%;transform:translateY(-50%);color:var(--muted);pointer-events:none}.chips{display:flex;gap:8px;overflow-x:auto;padding:2px 0 12px;scrollbar-width:none}.chips::-webkit-scrollbar{display:none}.chip{flex:0 0 auto;padding:7px 14px;border-radius:999px;background:var(--card);border:1px solid var(--border);font-size:13px;color:var(--muted);white-space:nowrap}.chip.active{background:var(--primary);border-color:var(--primary);color:#fff}.word-list{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:2px 14px}.word-row{display:flex;align-items:center;gap:12px;padding:13px 0;border-bottom:1px solid var(--border)}.word-row:last-child{border-bottom:none}.word-main{flex:1;min-width:0;cursor:pointer}.term{font-weight:600;font-size:16px}.sub{color:var(--muted);font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.badge{font-size:11px;padding:3px 9px;border-radius:999px;background:var(--primary-weak);color:var(--primary);flex:0 0 auto;white-space:nowrap}.badge.dim{background:transparent;border:1px solid var(--border);color:var(--muted)}.badge.ok{background:var(--ok-weak);color:var(--ok)}.tag{display:inline-block;font-size:12px;color:var(--primary);background:var(--primary-weak);border-radius:999px;padding:3px 10px}.session-top{display:flex;align-items:center;gap:12px;margin:14px 0}.session-top .count{font-size:13px;color:var(--muted);flex:0 0 auto}.flashcard{background:var(--card);border:1px solid var(--border);border-radius:20px;padding:28px 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small{font-weight:400;font-size:11px;opacity:.8}.grade.again{background:var(--danger-weak);color:var(--danger)}.grade.hard{background:var(--warn-weak);color:var(--warn)}.grade.good{background:var(--ok-weak);color:var(--ok)}.overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#00000073;display:flex;align-items:flex-end;justify-content:center;z-index:50}.sheet{width:100%;max-width:520px;background:var(--card);border-radius:20px 20px 0 0;padding:18px 20px calc(20px + env(safe-area-inset-bottom));max-height:88dvh;overflow:auto}.sheet-head{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:10px}.sheet-head h3{margin:0;font-size:20px;word-break:break-word}.field{margin-bottom:12px}.field label{display:block;font-size:13px;color:var(--muted);margin-bottom:6px}.field input,.field textarea{width:100%;padding:11px 14px;border-radius:12px;border:1px solid var(--border);background:var(--bg);color:var(--text);outline:none}.field input:focus,.field 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