:root{--bg: #f0f4ff;--bg-card: #ffffff;--bg-sidebar: #ffffff;--bg-input: #f5f7ff;--bg-hover: #eef2ff;--text: #1e293b;--text-secondary: #64748b;--text-muted: #94a3b8;--border: #e2e8f0;--accent: #6366f1;--accent-light: #a5b4fc;--accent-dark: #4f46e5;--gradient-1: linear-gradient(135deg, #6366f1, #8b5cf6);--gradient-2: linear-gradient(135deg, #ec4899, #f43f5e);--gradient-3: linear-gradient(135deg, #14b8a6, #06b6d4);--gradient-4: linear-gradient(135deg, #f59e0b, #f97316);--shadow-sm: 0 1px 3px rgba(0,0,0,.06);--shadow-md: 0 4px 12px rgba(0,0,0,.08);--shadow-lg: 0 8px 30px rgba(0,0,0,.1);--radius: 12px;--radius-lg: 16px;--radius-full: 9999px;--transition: .2s ease;color-scheme:light}[data-theme=dark]{--bg: #0f172a;--bg-card: #1e293b;--bg-sidebar: #1e293b;--bg-input: #334155;--bg-hover: #334155;--text: #f1f5f9;--text-secondary: #94a3b8;--text-muted: #64748b;--border: #334155;--accent-light: #818cf8;--shadow-sm: 0 1px 3px rgba(0,0,0,.2);--shadow-md: 0 4px 12px rgba(0,0,0,.3);--shadow-lg: 0 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.score-label{font-size:.75rem;color:#fffc;font-weight:500}.results-title{font-size:1.4rem;font-weight:800;margin-bottom:.5rem}.results-subtitle{color:var(--text-secondary);margin-bottom:1.5rem}.results-actions{display:flex;gap:.75rem;justify-content:center}.flashcards-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:1.5rem;flex-wrap:wrap;gap:1rem}.flashcards-header h2{font-size:1.3rem;font-weight:800}.deck-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:1rem;margin-bottom:1.5rem}.deck-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:1.25rem;cursor:pointer;transition:all 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.fc-hint{margin-top:1rem;font-size:.8rem;color:var(--text-muted)}.flashcard-controls{display:flex;justify-content:center;gap:.75rem;margin-top:1rem}.flashcard-controls .btn{min-width:120px}.upload-zone{border:2px dashed var(--border);border-radius:var(--radius-lg);padding:3rem 2rem;text-align:center;cursor:pointer;transition:all var(--transition);background:var(--bg-card)}.upload-zone:hover{border-color:var(--accent);background:#6366f108}.upload-zone .upload-icon{font-size:2.5rem;margin-bottom:.75rem}.upload-zone h3{font-weight:700;margin-bottom:.25rem}.upload-zone p{color:var(--text-muted);font-size:.85rem}.settings-section{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:1.5rem;margin-bottom:1rem}.settings-section h3{font-size:1rem;font-weight:700;margin-bottom:1rem}.setting-row{display:flex;align-items:center;justify-content:space-between;padding:.75rem 0;border-bottom:1px solid var(--border)}.setting-row:last-child{border-bottom:none}.setting-label{font-weight:500;font-size:.9rem}.setting-desc{font-size:.8rem;color:var(--text-muted)}.toggle{width:44px;height:24px;background:var(--border);border-radius:var(--radius-full);position:relative;cursor:pointer;transition:background var(--transition);flex-shrink:0}.toggle.on{background:var(--accent)}.toggle:after{content:"";position:absolute;width:18px;height:18px;background:#fff;border-radius:50%;top:3px;left:3px;transition:transform var(--transition);box-shadow:var(--shadow-sm)}.toggle.on:after{transform:translate(20px)}.empty-state{text-align:center;padding:3rem 2rem;color:var(--text-muted)}.empty-state .empty-icon{font-size:3rem;margin-bottom:.75rem}.badge{display:inline-flex;align-items:center;gap:.25rem;padding:.2rem .6rem;border-radius:var(--radius-full);font-size:.75rem;font-weight:600}.badge-purple{background:#6366f11f;color:var(--accent)}.badge-green{background:#10b9811f;color:#10b981}.badge-orange{background:#f59e0b1f;color:#f59e0b}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}@media(max-width:768px){.sidebar{transform:translate(-100%)}.sidebar.open{transform:translate(0)}.sidebar-overlay.show{display:block}.main-content{margin-left:0}.hamburger{display:block}.page-content{padding:1rem}.stats-grid{grid-template-columns:repeat(2,1fr)}.quick-actions{grid-template-columns:1fr 1fr}.quiz-options{grid-template-columns:1fr}.message{max-width:95%}.topbar{padding:.75rem 1rem}.chat-messages{padding:1rem}.chat-input-area{padding:.75rem 1rem}.deck-grid{grid-template-columns:1fr}.results-actions{flex-direction:column}.flashcards-header{flex-direction:column;align-items:flex-start}}@media(max-width:480px){.stats-grid,.quick-actions{grid-template-columns:1fr}.stat-card{padding:1rem}}