:root{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400}body{margin:0;padding:0}:root{--primary-orange: #ff9800;--primary-blue: #3178c6;--primary-purple: #663399;--bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);--glass-bg: rgba(255, 255, 255, .7);--glass-border: rgba(255, 255, 255, .3);--text-main: #2d3436;--text-muted: #636e72;--shadow-premium: 0 10px 30px rgba(0, 0, 0, .05);--header-height: 70px}*{box-sizing:border-box;margin:0;padding:0;-webkit-tap-highlight-color:transparent}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg-gradient);min-height:100vh;color:var(--text-main);overflow-x:hidden}.app-container{min-height:100vh;display:flex;flex-direction:column}.home-container{padding:40px 20px;max-width:1000px;margin:0 auto;width:100%}.home-header{margin-bottom:40px;text-align:left}.home-header h1{font-size:2.5rem;font-weight:800;background:linear-gradient(to right,#2d3436,#636e72);background-clip:text;-webkit-background-clip:text;-webkit-text-fill-color:transparent;margin-bottom:8px}.home-header p{color:var(--text-muted);font-size:1.1rem}.deck-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:24px}.deck-card{background:var(--glass-bg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border:1px solid var(--glass-border);border-radius:24px;padding:30px;display:flex;flex-direction:column;gap:16px;cursor:pointer;transition:all .4s cubic-bezier(.175,.885,.32,1.275);box-shadow:var(--shadow-premium);position:relative;overflow:hidden}.deck-card:hover{transform:translateY(-10px) scale(1.02);box-shadow:0 20px 40px #0000001a}.deck-card:before{content:"";position:absolute;top:0;left:0;width:100%;height:6px;background:var(--deck-color, 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white}.card-face.back{background:#fffcf0;transform:rotateY(180deg)}.card-text{font-size:1.8rem;font-weight:700;color:#2d3436;word-break:break-word}.card-label{position:absolute;top:24px;left:24px;font-size:.75rem;text-transform:uppercase;letter-spacing:2px;color:#b2bec3;font-weight:800}.navigation-controls{margin-top:50px;display:flex;flex-direction:column;align-items:center;gap:20px}.btn-circle{width:84px;height:84px;border-radius:50%;background:var(--primary-orange);color:#fff;border:none;display:flex;align-items:center;justify-content:center;cursor:pointer;box-shadow:0 15px 35px #ff980066;transition:all .3s cubic-bezier(.175,.885,.32,1.275)}.btn-circle:hover{transform:scale(1.1) rotate(5deg);box-shadow:0 20px 45px #ff980080}.btn-icon,.btn-text-premium{background:none;border:none;cursor:pointer;color:var(--text-muted);padding:10px;border-radius:12px;transition:all 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p{font-size:1rem}.deck-grid{grid-template-columns:1fr;gap:16px}.deck-card{padding:24px}.flashcard-wrapper{height:250px;max-width:100%}.card-text{font-size:1.4rem}.card-face{padding:24px}.srs-controls{grid-template-columns:repeat(2,1fr);gap:8px;max-width:200px}.btn-srs{font-size:.75rem;padding:10px 0;max-width:100%}.modal-content{width:95%;max-height:90vh;padding:24px;border-radius:24px}.modal-header-premium h2{font-size:1.3rem}.floating-action-premium{right:16px;bottom:16px}.btn-fab-premium{width:56px;height:56px}.top-bar{padding:0 16px;height:60px}.study-area{padding:16px}.btn-circle{width:72px;height:72px}}@media(min-width:481px)and (max-width:768px){.home-container{padding:30px 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svg{color:var(--primary-orange)}.modal-title{font-size:1.5rem;font-weight:700;margin:0;color:#1f2937}.modal-close-btn{background:#0000000d;border-radius:50%;transition:all .2s ease}.modal-close-btn:hover{background:#0000001a;transform:rotate(90deg)}.dashboard-body{padding:0}.dashboard-section{margin-bottom:32px}.section-header{display:flex;align-items:center;gap:10px;margin-bottom:16px}.section-header svg{color:var(--primary-orange)}.section-title{font-size:1.1rem;font-weight:600;margin:0;color:#374151}.dashboard-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px}@media(max-width:768px){.dashboard-grid{grid-template-columns:1fr}}.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:16px}.stat-card{display:flex;align-items:center;gap:16px;padding:20px;border-radius:16px;transition:all .2s ease}.stat-card:hover{transform:translateY(-2px);box-shadow:0 4px 12px #00000014}.stat-card-icon{display:flex;align-items:center;justify-content:center;width:48px;height:48px;border-radius:12px;background:#fffc}.stat-card-content{flex:1;min-width:0}.stat-card-value{font-size:1.75rem;font-weight:700;line-height:1.2;display:flex;align-items:center;gap:8px}.stat-trend{font-size:.875rem;font-weight:600}.stat-trend-up{color:#22c55e}.stat-trend-down{color:#ef4444}.stat-trend-neutral{color:#6b7280}.stat-card-label{font-size:.875rem;color:#6b7280;margin-top:4px;font-weight:500}.stat-card-subtext{font-size:.75rem;color:#9ca3af;margin-top:2px}.progress-chart{background:#f9fafb;border-radius:16px;padding:24px}.chart-bars{display:flex;align-items:flex-end;justify-content:space-around;height:150px;gap:12px;padding-bottom:32px;border-bottom:1px solid #e5e7eb;margin-bottom:16px}.chart-bar-container{flex:1;display:flex;flex-direction:column;align-items:center;gap:8px;min-width:40px}.chart-bar{width:100%;max-width:40px;border-radius:8px 8px 0 0;transition:all .3s ease;cursor:pointer}.chart-bar:hover{opacity:.8;transform:scaleY(1.05)}.chart-bar-label{font-size:.75rem;color:#6b7280;text-align:center;white-space:nowrap}.distribution-chart{background:#f9fafb;border-radius:16px;padding:24px;display:flex;align-items:center;gap:24px}.pie-chart{width:150px;height:150px;flex-shrink:0}.chart-legend-vertical{flex:1;display:flex;flex-direction:column;gap:12px}.chart-legend-vertical .legend-item{display:flex;align-items:center;gap:10px;font-size:.875rem}.chart-legend-vertical .legend-label{flex:1;color:#374151}.chart-legend-vertical .legend-value{font-weight:600;color:#1f2937;min-width:50px;text-align:right}.chart-legend{display:flex;gap:20px;justify-content:center;font-size:.75rem;color:#6b7280}.legend-item{display:flex;align-items:center;gap:6px}.legend-color{width:12px;height:12px;border-radius:3px}.dashboard-empty{text-align:center;padding:48px 24px;background:#f9fafb;border-radius:16px}.dashboard-empty p:first-child{font-size:1.1rem;font-weight:600;color:#374151;margin-bottom:8px}.dashboard-empty p:last-child{font-size:.875rem;color:#6b7280}.modal-footer{display:flex;justify-content:flex-end;padding-top:20px;border-top:1px solid #e5e7eb}.btn-secondary{background:#f3f4f6;color:#374151;border:none;padding:12px 24px;border-radius:12px;font-weight:600;cursor:pointer;transition:all .2s ease}.btn-secondary:hover{background:#e5e7eb;transform:translateY(-1px)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border-width:0}.empty-chart{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:48px 24px;background:#f9fafb;border-radius:16px;text-align:center}.empty-chart p:first-child{font-size:1rem;font-weight:600;color:#6b7280;margin-bottom:8px}.empty-chart p:last-child{font-size:.875rem;color:#9ca3af}@media(max-width:480px){.dashboard-modal{width:95%;max-height:95vh}.dashboard-modal .modal-header{padding-bottom:16px;margin-bottom:16px}.modal-title{font-size:1.25rem}.stats-grid{grid-template-columns:repeat(2,1fr);gap:12px}.stat-card{padding:16px;flex-direction:column;text-align:center;gap:12px}.stat-card-icon{width:40px;height:40px}.stat-card-value{font-size:1.5rem}.distribution-chart{flex-direction:column;padding:20px}.pie-chart{width:120px;height:120px}.chart-legend-vertical{width:100%}.progress-chart{padding:16px}.chart-bars{height:120px;gap:8px}.chart-bar{max-width:30px}.chart-bar-label{font-size:.65rem}}@media(max-width:768px){.dashboard-grid{grid-template-columns:1fr}.stats-grid{grid-template-columns:repeat(2,1fr)}}@media(min-width:1200px){.dashboard-modal{max-width:1000px}.stats-grid{grid-template-columns:repeat(3,1fr)}}