:root{color-scheme:dark;--bg: #0a0a0a;--surface: #141414;--surface-2: #1c1c1c;--surface-3: #262626;--border: #2e2e2e;--border-light: #3e3e3e;--text: #ffffff;--text-secondary: #b0b0b0;--text-muted: #707070;--accent: #ff7a1a;--accent-soft: rgba(255, 122, 26, .12);--accent-hover: rgba(255, 122, 26, .2);--accent-dim: #cc6215;--inverse: #0a0a0a;--success: #2ecc71;--danger: #e74c3c;--warning: #f39c12;--shadow-sm: 0 1px 4px rgba(0, 0, 0, .6);--shadow: 0 8px 32px rgba(0, 0, 0, .8);--radius: 14px;--radius-sm: 10px;--header-h: 64px;--safe-bottom: env(safe-area-inset-bottom, 0px)}*{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{font-family:Inter,system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;line-height:1.5;-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}.hidden{display:none!important}.password-gate{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:100vh;padding:24px;background:radial-gradient(ellipse at center,#1a1208,#0a0a0a 70%)}.password-card{background:var(--surface);border:1px solid var(--border);border-radius:20px;padding:36px 28px;max-width:380px;width:100%;text-align:center;box-shadow:var(--shadow)}.password-logo{font-size:2rem;font-weight:800;color:var(--accent);letter-spacing:-.03em;margin-bottom:6px}.password-sub{font-size:.85rem;color:var(--text-secondary);margin-bottom:24px}.password-input{width:100%;padding:14px 16px;border-radius:var(--radius-sm);border:1px solid 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16px;font-size:2rem}.tg-title{font-size:1.1rem;font-weight:700;margin-bottom:8px}.tg-desc{font-size:.85rem;color:var(--text-secondary);margin-bottom:20px;line-height:1.5}.tg-btn{display:inline-flex;align-items:center;gap:8px;padding:12px 24px;border-radius:var(--radius-sm);background:linear-gradient(135deg,#2aabee,#229ed9);color:#fff;font-weight:700;font-size:.9rem;text-decoration:none;border:none;cursor:pointer;transition:opacity .15s}.tg-btn:hover{opacity:.9}.tg-close{display:block;margin:12px auto 0;background:none;border:none;color:var(--text-muted);font-size:.8rem;cursor:pointer;font-family:inherit}.tg-close:hover{color:var(--text-secondary)}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.app-shell{width:100%;min-height:100vh;background:var(--bg)}.app-header{position:sticky;top:0;z-index:100;background:#0a0a0aeb;backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border-bottom:1px solid var(--border);padding:12px 16px 10px;padding-top:max(12px,env(safe-area-inset-top))}.header-row{display:flex;align-items:center;gap:10px}.header-text{flex:1;min-width:0}.app-logo{font-size:1.25rem;font-weight:800;color:var(--accent);letter-spacing:-.03em}.breadcrumb{font-size:.75rem;color:var(--text-secondary);margin-top:1px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.icon-btn{width:40px;height:40px;border:1px solid var(--border-light);border-radius:var(--radius-sm);background:var(--surface-2);color:var(--text);cursor:pointer;display:flex;align-items:center;justify-content:center;flex-shrink:0;transition:background .15s,border-color 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sepia(.2)}.series-card-cover-fallback{height:100px;background:linear-gradient(180deg,#1a1a1a,#111)}.series-card-cover.hidden{display:none}.series-card-body{display:flex;gap:12px;padding:14px 16px;align-items:flex-start}.series-card-logo-wrap{position:relative;flex-shrink:0;margin-top:-24px}.series-card-logo{width:52px;height:52px;border-radius:10px;object-fit:cover;border:2px solid var(--surface);background:var(--surface-2);display:block}.series-card-logo-fb{width:52px;height:52px;border-radius:10px;background:var(--surface-3);border:2px solid var(--surface);display:none;align-items:center;justify-content:center;font-size:1.3rem}.series-card-logo-wrap.fallback .series-card-logo{display:none}.series-card-logo-wrap.fallback 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infinite;border-radius:8px}.sk-avatar{width:48px;height:48px;border-radius:12px;flex-shrink:0}.sk-line{height:12px;margin-bottom:8px}.sk-line.lg{width:85%}.sk-line.sm{width:45%}@keyframes shimmer{0%{background-position:200% 0}to{background-position:-200% 0}}.empty-state{text-align:center;padding:60px 20px;color:var(--text-secondary)}.empty-icon{font-size:2.5rem;margin-bottom:12px;opacity:.5}.exam-screen{position:fixed;top:0;right:0;bottom:0;left:0;z-index:300;background:var(--bg);overflow-y:auto;width:100%}.exam-loading{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:60vh;gap:16px;color:var(--text-secondary)}.loader-ring{width:44px;height:44px;border:2px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.exam-header{display:flex;justify-content:space-between;align-items:flex-start;gap:12px;padding:14px 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var(--danger);color:var(--danger);font-size:1.2rem;cursor:pointer;display:flex;align-items:center;justify-content:center;font-family:inherit;transition:background .15s}.exam-exit-btn:hover{background:var(--danger);color:#fff}.exam-question{margin:16px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:18px;line-height:1.65;font-size:.92rem}.exam-question img,.opt-text img,.review-q img{max-width:100%;height:auto;display:block}.img-broken{min-width:64px;min-height:48px;background:var(--surface-2);border:1px dashed var(--border-light);border-radius:6px;object-fit:contain;padding:8px}.q-badge{display:inline-block;background:var(--accent);color:var(--inverse);font-size:.68rem;font-weight:700;padding:3px 10px;border-radius:999px;margin-bottom:12px}.exam-options{display:flex;flex-direction:column;gap:8px;padding:0 16px}.opt-btn{display:flex;gap:12px;align-items:flex-start;width:100%;text-align:left;padding:14px 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6px}.exam-palette{display:flex;flex-direction:row;flex-wrap:nowrap;overflow-x:auto;overflow-y:hidden;gap:8px;padding:0 16px 4px;-webkit-overflow-scrolling:touch;scroll-behavior:smooth;scrollbar-width:thin;scrollbar-color:var(--border-light) transparent}.exam-palette::-webkit-scrollbar{height:4px}.exam-palette::-webkit-scrollbar-thumb{background:var(--border-light);border-radius:4px}.palette-item{flex-shrink:0;width:42px;height:42px;min-width:42px;border-radius:10px;border:1px solid var(--border);background:var(--surface-2);color:var(--text-secondary);font-size:.78rem;font-weight:600;cursor:pointer;transition:border-color .12s,background .12s;scroll-snap-align:center}.exam-palette-panel{position:fixed;left:50%;transform:translate(-50%);bottom:0;width:100%;max-width:480px;background:var(--surface);border-top:1px solid var(--border-light);z-index:520;max-height:65vh;display:flex;flex-direction:column;box-shadow:0 -8px 32px 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var(--accent);outline-offset:1px;color:var(--accent)}.exam-palette{scroll-snap-type:x proximity}.exam-footer{padding:16px;padding-bottom:max(16px,var(--safe-bottom));display:grid;grid-template-columns:1fr 1fr 1fr;gap:8px;background:#0a0a0af2;border-top:1px solid var(--border);position:sticky;bottom:0;z-index:50}.exam-footer .btn-block{grid-column:1 / -1;margin-top:4px}.exam-result-wrap{padding:24px 16px 32px;max-width:640px;margin:0 auto}.result-header{text-align:center;margin-bottom:24px}.result-score-ring{width:96px;height:96px;border-radius:50%;background:var(--accent);color:var(--inverse);font-size:1.5rem;font-weight:800;display:flex;align-items:center;justify-content:center;margin:0 auto 16px;border:3px solid var(--border-light)}.result-header h2{font-size:1.25rem;font-weight:800}.result-sub{font-size:.85rem;color:var(--text-secondary);margin-top:4px}.result-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;margin-bottom:20px}.result-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);padding:14px;text-align:center}.result-card .val{font-size:1.5rem;font-weight:800;color:var(--text)}.result-card .lbl{font-size:.72rem;color:var(--text-secondary);margin-top:2px}.result-card.green .val{color:var(--success)}.result-card.red .val{color:var(--danger)}.result-card.blue .val{color:var(--accent)}.result-card.gold .val{color:var(--warning)}.result-actions{display:flex;flex-direction:column;gap:10px}.review-top{display:flex;justify-content:space-between;align-items:center;padding:16px;background:#0a0a0af2;border-bottom:1px solid var(--border);position:sticky;top:0;z-index:10}.review-top h2{font-size:1rem;font-weight:700}.review-list{padding:12px 16px 32px;max-width:800px;margin:0 auto}.review-item{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);padding:16px;margin-bottom:10px}.review-item.correct{border-left:3px solid var(--success)}.review-item.wrong{border-left:3px solid var(--danger)}.review-item.unattempted{border-left:3px solid var(--border-light)}.review-status{font-size:.68rem;font-weight:700;text-transform:uppercase;letter-spacing:.06em;margin-bottom:8px;color:var(--text-secondary)}.review-status.correct{color:var(--success)}.review-status.wrong{color:var(--danger)}.review-status.unattempted{color:var(--text-muted)}.review-q{line-height:1.55;font-size:.88rem;margin-bottom:10px}.review-ans{font-size:.82rem;padding:6px 0;border-top:1px solid var(--border)}.review-ans span{color:var(--text-secondary);font-weight:500}.review-solution{margin-top:10px;padding:12px;background:var(--surface-2);border-radius:var(--radius-sm);font-size:.82rem;line-height:1.55;border-left:2px solid var(--accent)}@media (min-width: 640px){.app-header{padding:14px 24px 12px}.app-main{padding:20px 24px 32px}.card-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.series-hero-banner{height:160px}.series-hero-banner-fallback{height:120px}.series-card-cover{height:150px}.exam-question{margin:20px 24px;font-size:.95rem}.exam-options{padding:0 24px}.exam-palette{padding:0 24px 4px}.exam-palette-label{padding-left:24px;padding-right:24px}.exam-footer{padding:16px 24px}}@media (min-width: 1024px){.app-shell{max-width:1200px;margin:0 auto;border-left:1px solid var(--border);border-right:1px solid var(--border)}.app-header{padding:16px 32px 14px}.header-row{max-width:100%}.search-box{max-width:480px}.app-main{padding:24px 32px 40px}.card-grid{grid-template-columns:repeat(3,1fr);gap:16px}.card-grid.grid-2{grid-template-columns:repeat(2,1fr)}.series-hero{display:flex;flex-direction:row;align-items:stretch}.series-hero-banner,.series-hero-banner-fallback{width:280px;height:auto;min-height:120px;flex-shrink:0}.series-hero-body{flex:1;padding:20px 24px}.series-hero-title{font-size:1.05rem}.result-grid{grid-template-columns:repeat(3,1fr)}.mock-card-actions{grid-template-columns:1fr 1fr}}@media (min-width: 1280px){.app-shell{max-width:1280px}.card-grid{gap:18px}}