:root{--bg:#f8f7f4;--surface:#ffffff;--border:#e2e0db;--text:#1a1a1a;--text-muted:#6b6b6b;--accent:#2563eb;--accent-text:#ffffff;--green:#16a34a;--red:#dc2626;--orange:#ea580c;--amber:#b45309;--gray:#9ca3af;--radius:8px;--shadow:0 1px 3px rgba(0,0,0,0.08)}@media (prefers-color-scheme:dark){:root{--bg:#111111;--surface:#1e1e1e;--border:#2e2e2e;--text:#f0f0f0;--text-muted:#888;--amber:#fcd34d}}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,sans-serif;font-size:16px;line-height:1.5}body.has-bg{background-position:50%;background-size:cover;background-repeat:no-repeat;background-attachment:fixed;--bg:#111111;--surface:#1e1e1e;--border:#2e2e2e;--text:#f0f0f0;--text-muted:#aaa;--amber:#fcd34d;color:#f0f0f0}body.has-bg:before{content:"";position:fixed;inset:0;background:rgba(0,0,0,.55);z-index:0;pointer-events:none;transition:background .4s ease}body.has-bg .app{position:relative;z-index:1}body.has-bg 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rgba(0,0,0,.5);background:rgba(0,0,0,.45);padding:20px 28px;border-radius:12px}.bg-showcase-title{font-size:28px;font-weight:700;letter-spacing:-.5px;margin-bottom:8px}.bg-showcase-desc{font-size:16px;font-weight:400;opacity:.9;max-width:400px;line-height:1.5}.bg-showcase-nav{display:flex;align-items:center;justify-content:center;gap:16px;margin-bottom:12px}.bg-showcase-center{width:220px;text-align:center;flex-shrink:0}.bg-showcase-arrow{background:rgba(255,255,255,.15);border:1px solid rgba(255,255,255,.2);color:#fff;font-size:18px;width:40px;height:40px;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s ease}.bg-showcase-arrow:hover:not(:disabled){background:rgba(255,255,255,.3)}.bg-showcase-arrow:disabled{opacity:.2;cursor:default}.bg-showcase-dismiss{font-size:12px;opacity:.5;margin-top:16px;cursor:pointer}@keyframes 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10px;text-align:center;box-shadow:var(--shadow)}.bucket-card-learning{border-top-color:var(--accent)}.bucket-card-learned{border-top-color:var(--orange)}.bucket-card-mastered{border-top-color:var(--green)}.bucket-name{font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.7px;color:var(--text-muted);margin-bottom:8px}.bucket-sub-counts{justify-content:center;gap:10px}.bucket-sub,.bucket-sub-counts{display:flex;align-items:center}.bucket-sub{flex-direction:column;gap:2px}.bucket-sub-num{font-size:22px;font-weight:700;line-height:1;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.bucket-sub-num-muted{color:var(--gray)!important}.bucket-sub-label{font-size:9px;color:var(--text-muted);text-transform:uppercase;letter-spacing:.4px}.bucket-sub-divider{width:1px;height:26px;background:var(--border);flex-shrink:0}.bucket-card-learning .bucket-sub-num{color:var(--accent)}.bucket-card-learned .bucket-sub-num{color:var(--orange)}.bucket-card-mastered 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(prefers-color-scheme:dark){.move-toast-promote{background:#052e16;color:#86efac;border-color:#14532d}.move-toast-master{background:#422006;color:#fcd34d;border-color:#78350f}.move-toast-demote{background:#450a0a;color:#fca5a5;border-color:#7f1d1d}}.drill-card{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:28px 20px 22px;text-align:center;margin-bottom:14px}.drill-emoji{font-size:60px;line-height:1;margin-bottom:12px}.drill-prompt{font-size:30px;font-weight:700;margin-bottom:12px;letter-spacing:-.3px}.drill-bucket-tag{display:inline-block;font-size:11px;font-weight:600;text-transform:uppercase;letter-spacing:.6px;padding:2px 9px;border-radius:99px}.bucket-tag-learning{background:#dbeafe;color:#1d4ed8}.bucket-tag-learned{background:#fed7aa;color:#c2410c}.bucket-tag-mastered{background:#dcfce7;color:#15803d}.bucket-tag-unseen{background:var(--border);color:var(--text-muted)}@media (prefers-color-scheme:dark){.bucket-tag-learning{background:#1e3a5f;color:#60a5fa}.bucket-tag-learned{background:#431407;color:#fb923c}.bucket-tag-mastered{background:#14532d;color:#4ade80}}.feedback{font-size:15px;font-weight:600;padding:9px 12px;border-radius:var(--radius);margin-bottom:12px;display:flex;align-items:center;gap:8px}.feedback-wrong{background:#fee2e2;color:var(--red)}.feedback-correct{background:#dcfce7;color:#15803d}.feedback-revealed{background:#fef9c3;color:#854d0e}@media (prefers-color-scheme:dark){.feedback-wrong{background:#450a0a;color:#fca5a5}.feedback-correct{background:#052e16;color:#86efac}.feedback-revealed{background:#422006;color:#fcd34d}}.feedback-icon{flex-shrink:0;font-size:14px;opacity:.85}.feedback-attempt{margin-left:auto;font-size:11px;font-weight:700;letter-spacing:.3px;background:rgba(0,0,0,.1);padding:1px 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16px;border:none;border-radius:var(--radius);font-size:15px;font-weight:600;cursor:pointer;white-space:nowrap}.btn-submit{background:var(--accent)}.btn-next,.btn-submit{color:var(--accent-text)}.btn-next{background:var(--green)}.btn:hover{opacity:.88}.btn:active{opacity:.75}.drill-hint{font-size:12px;color:var(--text-muted);text-align:center}.session-stats{display:flex;align-items:center;justify-content:center;gap:8px;font-size:13px}.stat-sep{color:var(--border)}.stat{font-weight:600;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.stat-correct{color:var(--green)}.stat-wrong{color:var(--red)}.stat-promoted{color:var(--accent)}.stat-demoted{color:var(--orange)}.all-done{text-align:center;padding:40px 20px}.all-done-icon{font-size:56px;margin-bottom:12px}.all-done-text{font-size:22px;font-weight:700;margin-bottom:8px}.all-done-sub{font-size:14px;color:var(--text-muted)}@keyframes bucket-mastered{0%{transform:scale(1);box-shadow:none}20%{transform:scale(1.08);box-shadow:0 0 0 3px #16a34a,0 0 16px rgba(22,163,74,.4)}40%{transform:scale(.97)}60%{transform:scale(1.04);box-shadow:0 0 0 2px #16a34a,0 0 10px rgba(22,163,74,.25)}80%{transform:scale(.99)}to{transform:scale(1);box-shadow:none}}@keyframes bucket-learned{0%{transform:scale(1)}30%{transform:scale(1.04);box-shadow:0 0 0 2px var(--accent)}70%{transform:scale(.98)}to{transform:scale(1);box-shadow:none}}.bucket-card-animate-mastered{animation:bucket-mastered .6s ease-out forwards}.bucket-card-animate-learned{animation:bucket-learned .4s ease-out forwards}