*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--color-bg: #f7f7f5;--color-surface: #ffffff;--color-surface-2: #f0efe9;--color-border: #e0dfd8;--color-text: #1a1a18;--color-text-muted: #7a7a72;--color-primary: #2d6a4f;--color-primary-hover: #1b4332;--color-danger: #c0392b;--color-danger-hover: #962d22;--color-again: #e74c3c;--color-hard: #e67e22;--color-good: #2ecc71;--color-easy: #3498db;--radius: 10px;--radius-sm: 6px;--shadow: 0 2px 8px rgba(0, 0, 0, .07);--shadow-lg: 0 8px 32px rgba(0, 0, 0, .12);--transition: .16s ease;--font: system-ui, -apple-system, "Segoe UI", sans-serif;--max-width: 680px}@media(prefers-color-scheme:dark){:root{--color-bg: #18181a;--color-surface: #242426;--color-surface-2: #2e2e30;--color-border: #3a3a3c;--color-text: #f0f0ee;--color-text-muted: #888886;--color-primary: #52b788;--color-primary-hover: 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p{margin-bottom:1rem}.modal-backdrop{position:fixed;inset:0;background:#00000073;display:flex;align-items:center;justify-content:center;padding:1rem;z-index:100;animation:fadeIn .12s ease}.modal{background:var(--color-surface);border-radius:var(--radius);padding:1.5rem;width:100%;max-width:480px;display:flex;flex-direction:column;gap:1rem;box-shadow:var(--shadow-lg);animation:slideUp .16s ease}.modal-title{font-size:1.05rem;font-weight:600}.modal-footer{display:flex;justify-content:flex-end;gap:.5rem;margin-top:.5rem}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{transform:translateY(12px);opacity:0}to{transform:translateY(0);opacity:1}}.badge{display:inline-flex;align-items:center;padding:.15rem 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var(--color-border);box-shadow:var(--shadow-lg);backface-visibility:hidden;-webkit-backface-visibility:hidden;text-align:center;overflow:hidden;height:auto}.card-front{position:relative}.card-back{transform:rotateY(180deg);background:var(--color-surface-2)}.card-text{font-size:clamp(1.1rem,3vw,1.5rem);font-weight:500;line-height:1.4;word-break:break-word;white-space:pre-wrap}.card-hint{margin-top:1.5rem;font-size:.8rem;color:var(--color-text-muted);display:flex;align-items:center;gap:.3em}.rating-bar{display:flex;gap:.5rem;margin-top:1.25rem;width:100%;max-width:560px;margin-left:auto;margin-right:auto;animation:fadeIn .2s ease}.btn-rating{flex:1;display:flex;flex-direction:column;align-items:center;gap:.2rem;padding:.65rem .4rem;border:2px solid transparent;border-radius:var(--radius-sm);cursor:pointer;font-family:var(--font);font-weight:600;font-size:.85rem;transition:transform .1s ease,filter .12s 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