:root{--bg: #0a0a0a;--bg-elev: #141414;--bg-elev-2: #1c1c1c;--border: #262626;--border-strong: #3a3a3a;--cream: #f5e6d3;--cream-dim: #d9c9b4;--cream-mute: #8a7e6e;--text: #f5e6d3;--text-dim: #b8aa97;--text-mute: #6e6457;--accent: #f5e6d3;--accent-hover: #ffffff;--success: #6fcf97;--error: #eb6c6c;--warning: #f0c674;--radius: 14px;--radius-sm: 10px;--radius-lg: 22px;--shadow: 0 4px 24px rgba(0,0,0,.4);--shadow-hover: 0 8px 32px rgba(245, 230, 211, .08);--font: "Inter", -apple-system, BlinkMacSystemFont, "SF Pro Text", sans-serif;--font-mono: "JetBrains Mono", "SF Mono", Menlo, 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h4{font-size:15px;font-weight:600;color:var(--cream);letter-spacing:-.01em;line-height:1.3}.topic-card .progress-row{display:flex;align-items:center;gap:10px;margin-top:4px}.progress-bar{flex:1;height:4px;background:var(--border);border-radius:2px;overflow:hidden}.progress-fill{height:100%;background:var(--cream);border-radius:2px;transition:width .4s cubic-bezier(.16,1,.3,1)}.progress-label{font-size:11px;color:var(--text-mute);font-variant-numeric:tabular-nums;min-width:30px;text-align:right}.question-card{background:var(--bg-elev);border:1px solid 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.flashcard-inner{transform:rotateY(180deg)}.flashcard-face{position:absolute;top:0;right:0;bottom:0;left:0;-webkit-backface-visibility:hidden;backface-visibility:hidden;background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius-lg);padding:48px;display:flex;align-items:center;justify-content:center;text-align:center}.flashcard-face.back{transform:rotateY(180deg);background:var(--bg-elev-2);border-color:var(--cream-mute)}.flashcard-face .label{position:absolute;top:18px;left:24px;font-size:10px;text-transform:uppercase;letter-spacing:.12em;color:var(--text-mute);font-weight:600}.flashcard-face .content{font-size:22px;color:var(--cream);line-height:1.5;font-weight:500;letter-spacing:-.01em;max-height:100%;overflow-y:auto;white-space:pre-wrap}.flashcard-face.back .content{font-weight:400;font-size:17px;color:var(--text-dim)}.cheatsheet{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius-lg);padding:44px 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24px}.exam-results .score-big{font-size:88px;font-weight:700;color:var(--cream);letter-spacing:-.04em;line-height:1;margin-bottom:12px;font-variant-numeric:tabular-nums}.exam-results .score-sub{font-size:18px;color:var(--text-dim);margin-bottom:32px}.exam-results .breakdown{display:grid;grid-template-columns:repeat(auto-fit,minmax(120px,1fr));gap:14px;max-width:600px;margin:32px auto}.exam-results .breakdown .cell{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius-sm);padding:16px}.exam-results .breakdown .cell .v{font-size:26px;font-weight:600;color:var(--cream)}.exam-results .breakdown .cell .l{font-size:12px;color:var(--text-mute);text-transform:uppercase;letter-spacing:.06em;margin-top:4px}.drill-tabs{display:flex;gap:8px;margin-bottom:28px;background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius);padding:5px;width:fit-content}.drill-tab{padding:9px 22px;font-size:14px;font-weight:500;color:var(--text-dim);border-radius:var(--radius-sm);transition:all .15s ease}.drill-tab.active{background:var(--cream);color:#0a0a0a;font-weight:600}.drill-tab:not(.active):hover{color:var(--cream)}.drill-counter{display:flex;gap:18px;margin-bottom:24px;font-size:13px;color:var(--text-mute);text-transform:uppercase;letter-spacing:.06em}.drill-counter strong{color:var(--cream);font-weight:600}.streak-badge{display:inline-flex;align-items:center;gap:8px;padding:6px 14px;background:#f5e6d30f;border:1px solid var(--cream-mute);border-radius:999px;font-size:13px;color:var(--cream);font-weight:500}.empty{text-align:center;padding:80px 24px;color:var(--text-mute)}::-webkit-scrollbar{width:10px;height:10px}::-webkit-scrollbar-track{background:var(--bg)}::-webkit-scrollbar-thumb{background:var(--border-strong);border-radius:5px}::-webkit-scrollbar-thumb:hover{background:var(--cream-mute)}@media (max-width: 720px){.topbar{padding:16px 20px}.container{padding:32px 20px 60px}.hero h1{font-size:38px}.question-card{padding:26px}.question-text{font-size:17px}.cheatsheet{padding:28px 24px}.flashcard{height:320px}.flashcard-face{padding:28px}.flashcard-face .content{font-size:18px}.exam-results .score-big{font-size:64px}}