:root{--bg: #0f1226;--bg-soft: #171a35;--card: #1e2244;--card-hover: #262b54;--text: #eef1ff;--muted: #a6abd4;--accent: #6c8cff;--accent-2: #a06bff;--good: #2ee6a6;--good-bg: rgba(46, 230, 166, .14);--bad: #ff5d73;--bad-bg: rgba(255, 93, 115, .14);--gold: #ffd166;--radius: 18px;--shadow: 0 12px 40px rgba(0, 0, 0, .35);--font: "Inter", "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif}@media (prefers-color-scheme: light){:root{--bg: #f3f5ff;--bg-soft: #e9ecfb;--card: #ffffff;--card-hover: #f4f6ff;--text: #16182e;--muted: #5a6080;--shadow: 0 12px 40px rgba(40, 50, 110, .12)}}*{box-sizing:border-box}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.skip-link{position:fixed;top:8px;left:8px;z-index:1000;padding:10px 16px;border-radius:10px;background:var(--accent);color:#fff;font-weight:700;text-decoration:none;transform:translateY(-150%);transition:transform .15s 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var(--bg-soft);background:var(--bg-soft);color:inherit;font-family:inherit}.study-search:focus{outline:none;border-color:var(--accent, #6c8cff)}.study-controls{display:flex;align-items:center;gap:12px;margin-top:12px;flex-wrap:wrap}.study-cat{font-family:inherit;font-size:.9rem;padding:4px 8px;border-radius:8px;border:1px solid var(--bg-soft);background:var(--bg-soft);color:inherit}.study-item .study-answer{margin:8px 0;line-height:1.5}.study-item .explanation{line-height:1.5;margin-bottom:8px}.study-item .citation{font-size:.85rem;color:var(--muted);font-weight:700}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}.combo-flash,.shake{animation:none!important}}h2.prompt{font-size:1.2rem}