.prep-root{min-height:100vh;background:#0b1120;color:#e2e8f0;font-family:JetBrains Mono,IBM Plex Mono,monospace}.prep-header{background:#0d1225;border-bottom:1px solid rgba(255,255,255,.055);padding:13px 18px;display:flex;align-items:center;justify-content:space-between;position:sticky;top:0;z-index:10;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.prep-header-title{font-size:14px;font-weight:700;color:#22d3ee;letter-spacing:3px;text-decoration:none}.prep-header-sub{font-size:9px;color:#334155;margin-top:2px;letter-spacing:1.5px}.prep-header-streak{text-align:right}.prep-header-streak-value{font-size:22px;font-weight:700}.prep-header-streak-label{font-size:9px;color:#334155;letter-spacing:1px}.prep-container{max-width:520px;margin:0 auto;padding:20px 16px 40px}.prep-back-link{display:inline-flex;align-items:center;gap:6px;font-size:11px;color:#475569;text-decoration:none;margin-bottom:20px;transition:color .2s;font-family:JetBrains Mono,monospace}.prep-back-link:hover{color:#22d3ee}.prep-tabs{display:flex;border-bottom:1px solid rgba(255,255,255,.055);margin-bottom:22px;gap:0}.prep-tab-btn{padding:10px 18px;background:transparent;border:none;border-bottom:2px solid transparent;color:#475569;font-family:JetBrains Mono,monospace;font-size:12px;cursor:pointer;transition:all .2s;white-space:nowrap}.prep-tab-btn:hover{color:#94a3b8}.prep-tab-btn.active{color:#22d3ee;border-bottom-color:#22d3ee}.prep-card{background:#111827;border:1px solid rgba(255,255,255,.06);border-radius:14px;padding:20px;margin-bottom:14px}.prep-card-glow{border-color:#22d3ee26;box-shadow:0 0 30px #22d3ee0a}.prep-card-blue{border-color:#38bdf826}.prep-card-gradient{background:linear-gradient(135deg,#22d3ee0d,#38bdf808)}.prep-tag{font-size:9px;letter-spacing:2.5px;font-weight:600;margin-bottom:10px;text-transform:uppercase}.prep-btn{width:100%;padding:14px;border-radius:10px;font-family:JetBrains Mono,monospace;font-weight:600;font-size:13px;cursor:pointer;transition:all .25s;border:none;letter-spacing:.5px;display:flex;align-items:center;justify-content:center;gap:8px}.prep-btn:disabled{opacity:.35;cursor:not-allowed;transform:none!important}.prep-btn-primary{background:linear-gradient(135deg,#22d3ee,#0ea5e9);color:#0b1120}.prep-btn-primary:hover:not(:disabled){opacity:.9;transform:translateY(-2px);box-shadow:0 6px 20px #22d3ee40}.prep-btn-reveal{background:linear-gradient(135deg,#151e32,#1e293b);color:#22d3ee;border:1px solid rgba(34,211,238,.2)!important}.prep-btn-reveal:hover:not(:disabled){border-color:#22d3ee80!important;transform:translateY(-1px)}.prep-btn-ghost{background:transparent;color:#22d3ee;border:1px solid rgba(34,211,238,.2)}.prep-btn-ghost:hover:not(:disabled){border-color:#22d3ee80;background:#22d3ee0d;transform:translateY(-1px)}.prep-btn-danger{background:transparent;color:#f87171;border:1px solid rgba(248,113,113,.2)}.prep-btn-danger:hover:not(:disabled){border-color:#f8717180;background:#f871710d}.prep-topic-chip{padding:8px 14px;border-radius:20px;border:1px solid rgba(255,255,255,.08);background:#ffffff0a;font-size:11px;cursor:pointer;transition:all .2s;font-family:JetBrains Mono,monospace;color:#94a3b8;white-space:nowrap}.prep-topic-chip:hover,.prep-topic-chip.active{border-color:#22d3ee;color:#22d3ee;background:#22d3ee14}.prep-diff-btn{padding:6px 14px;border-radius:6px;border:1px solid transparent;font-family:JetBrains Mono,monospace;font-size:11px;cursor:pointer;background:transparent;transition:all .2s}.prep-diff-easy{color:#34d399;border-color:#34d39940}.prep-diff-easy.on{background:#34d3991f;border-color:#34d399}.prep-diff-medium{color:#fbbf24;border-color:#fbbf2440}.prep-diff-medium.on{background:#fbbf241f;border-color:#fbbf24}.prep-diff-hard{color:#f87171;border-color:#f8717140}.prep-diff-hard.on{background:#f871711f;border-color:#f87171}.code-block-wrapper{position:relative;margin:14px 0;border-radius:10px;overflow:hidden;border:1px solid rgba(255,255,255,.08);background:#0d1117}.code-block-header{display:flex;align-items:center;justify-content:space-between;padding:8px 14px;background:#161b22;border-bottom:1px solid rgba(255,255,255,.06)}.code-block-lang{font-size:10px;color:#475569;letter-spacing:1.5px;text-transform:uppercase;font-family:JetBrains Mono,monospace}.code-block-copy{display:flex;align-items:center;gap:5px;padding:4px 10px;border-radius:5px;border:1px solid rgba(255,255,255,.1);background:#ffffff0a;color:#94a3b8;font-size:11px;font-family:JetBrains Mono,monospace;cursor:pointer;transition:all .2s}.code-block-copy:hover{background:#22d3ee1a;border-color:#22d3ee4d;color:#22d3ee}.code-block-copy.copied{background:#34d39926;border-color:#34d39966;color:#34d399}.code-block-pre{padding:16px;margin:0;overflow-x:auto;font-family:JetBrains Mono,monospace;font-size:12.5px;line-height:1.7;color:#e2e8f0;-moz-tab-size:2;tab-size:2}.code-block-pre code{font-family:inherit}.code-block-pre .kw{color:#c792ea}.code-block-pre .type{color:#82aaff}.code-block-pre .str{color:#c3e88d}.code-block-pre .num{color:#f78c6c}.code-block-pre .comment{color:#546e7a;font-style:italic}.code-block-pre .annotation{color:#ffcb6b}.code-block-pre .method{color:#82aaff}.code-block-pre .punc{color:#89ddff}.mcq-option{display:flex;align-items:flex-start;gap:12px;padding:14px 16px;border-radius:10px;border:1px solid rgba(255,255,255,.08);background:#ffffff05;cursor:pointer;transition:all .2s;margin-bottom:10px;font-family:Inter,Space Grotesk,sans-serif;font-size:13px;line-height:1.6;color:#cbd5e1}.mcq-option:hover:not(.mcq-answered){border-color:#22d3ee66;background:#22d3ee0a}.mcq-option.mcq-selected{border-color:#22d3ee80;background:#22d3ee14}.mcq-option.mcq-correct{border-color:#34d39999;background:#34d39914;color:#a7f3d0}.mcq-option.mcq-wrong{border-color:#f8717199;background:#f871710f;color:#fca5a5}.mcq-option.mcq-answered{cursor:default;opacity:.7}.mcq-option.mcq-correct.mcq-answered,.mcq-option.mcq-wrong.mcq-selected.mcq-answered{opacity:1}.mcq-option-letter{flex-shrink:0;width:28px;height:28px;border-radius:6px;border:1px solid rgba(255,255,255,.12);display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:600;font-family:JetBrains Mono,monospace;color:#64748b;background:#ffffff08}.mcq-correct .mcq-option-letter{border-color:#34d399;color:#34d399;background:#34d3991a}.mcq-wrong.mcq-selected .mcq-option-letter{border-color:#f87171;color:#f87171;background:#f871711a}.mcq-option .code-block-wrapper{margin:8px 0 4px;border-radius:8px}.mcq-option .code-block-pre{padding:10px 12px;font-size:11.5px;line-height:1.5}.mcq-option .code-block-header{padding:5px 10px}.mcq-score-bar{display:flex;align-items:center;gap:16px;padding:12px 16px;background:#111827;border-radius:10px;border:1px solid rgba(255,255,255,.06);margin-bottom:16px}.mcq-score-item{display:flex;flex-direction:column;align-items:center;gap:2px}.mcq-score-value{font-size:18px;font-weight:700;font-family:JetBrains Mono,monospace}.mcq-score-label{font-size:9px;color:#475569;letter-spacing:1px;text-transform:uppercase}.mcq-progress-bar{flex:1;height:4px;background:#1e293b;border-radius:2px;overflow:hidden}.mcq-progress-fill{height:100%;background:linear-gradient(90deg,#22d3ee,#0ea5e9);border-radius:2px;transition:width .4s ease}.prep-timer{display:inline-flex;align-items:center;gap:6px;padding:5px 12px;border-radius:6px;font-size:13px;font-family:JetBrains Mono,monospace;font-weight:600;border:1px solid rgba(255,255,255,.08);background:#ffffff08}.prep-timer.warning{color:#fbbf24;border-color:#fbbf244d;background:#fbbf240f}.prep-timer.danger{color:#f87171;border-color:#f871714d;background:#f871710f;animation:timer-pulse .8s infinite}@keyframes timer-pulse{0%,to{opacity:1}50%{opacity:.5}}.prep-stats-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:16px}.prep-stat-card{padding:14px 10px;border-radius:10px;background:#111827;border:1px solid rgba(255,255,255,.06);text-align:center}.prep-stat-value{font-size:20px;font-weight:700;font-family:JetBrains Mono,monospace;color:#22d3ee}.prep-stat-label{font-size:9px;color:#475569;letter-spacing:1px;margin-top:4px;text-transform:uppercase}@keyframes prep-pulse{0%,to{opacity:1}50%{opacity:.4}}@keyframes prep-fadeUp{0%{opacity:0;transform:translateY(12px)}to{opacity:1;transform:translateY(0)}}@keyframes prep-slideIn{0%{opacity:0;transform:translate(-8px)}to{opacity:1;transform:translate(0)}}.prep-pulse{animation:prep-pulse 1.8s infinite}.prep-fade-up{animation:prep-fadeUp .35s ease}.prep-slide-in{animation:prep-slideIn .3s ease}.prep-footer{margin-top:40px;padding-top:16px;border-top:1px solid rgba(255,255,255,.04);font-size:10px;color:#1e293b;text-align:center;line-height:2.2;letter-spacing:.5px}.prep-footer a{color:#22d3ee26;text-decoration:none}.prep-hint-block{margin-top:12px;padding:10px 14px;border-radius:8px;display:flex;flex-direction:column;gap:4px}.prep-hint-block-label{font-size:9px;letter-spacing:1.5px;font-weight:600}.prep-hint-block-text{font-size:12px;line-height:1.6;font-family:Inter,Space Grotesk,sans-serif}.prep-answer-text{font-size:13.5px;line-height:1.8;color:#c8d6e5;font-family:Inter,Space Grotesk,sans-serif;white-space:pre-wrap;word-break:break-word}.prep-key-point{display:flex;gap:10px;margin-bottom:8px;font-size:12.5px;color:#94a3b8;line-height:1.6;font-family:Inter,Space Grotesk,sans-serif}.prep-key-point-bullet{color:#22d3ee;flex-shrink:0;font-weight:700}.prep-loader{text-align:center;padding:40px}.prep-loader-text{font-size:12px;color:#22d3ee59}@media(max-width:480px){.prep-container{padding:14px 12px 30px}.prep-tab-btn{padding:8px 12px;font-size:11px}.prep-stats-grid{grid-template-columns:repeat(3,1fr);gap:6px}.prep-stat-card{padding:10px 6px}.prep-stat-value{font-size:16px}.mcq-option{padding:12px;font-size:12px}.code-block-pre{font-size:11.5px;padding:12px}}