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var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out);justify-content:center;align-items:center;display:flex}.mode-card-icon svg{flex-shrink:0;width:24px;height:24px}.mode-card:hover .mode-card-icon,.mode-card.selected .mode-card-icon{background:var(--color-primary);color:#fff}.mode-card-title{font-size:var(--text-base);font-weight:var(--font-semibold);color:var(--color-text-primary)}.mode-card-desc{font-size:var(--text-sm);color:var(--color-text-secondary);line-height:var(--leading-relaxed)}.heatmap{gap:var(--space-1);flex-direction:column;display:flex}.heatmap-row{gap:var(--space-1);display:flex}.heatmap-cell{border-radius:var(--radius-sm);background:var(--color-border-subtle);width:14px;height:14px;transition:background-color var(--duration-fast) var(--ease-out);cursor:default}.heatmap-cell[data-level="1"]{background:#c7d2fe}.heatmap-cell[data-level="2"]{background:#818cf8}.heatmap-cell[data-level="3"]{background:#4f46e5}.heatmap-cell[data-level="4"]{background:#3730a3}[data-theme=dark] .heatmap-cell[data-level="1"]{background:#312e81}[data-theme=dark] .heatmap-cell[data-level="2"]{background:#4338ca}[data-theme=dark] .heatmap-cell[data-level="3"]{background:#818cf8}[data-theme=dark] .heatmap-cell[data-level="4"]{background:#a5b4fc}.table-wrapper{border:1px solid var(--color-border);border-radius:var(--radius-xl);overflow-x:auto}table{border-collapse:collapse;width:100%;font-size:var(--text-sm)}thead tr{background:var(--color-border-subtle)}th{padding:var(--space-3) var(--space-4);text-align:left;font-weight:var(--font-semibold);color:var(--color-text-secondary);font-size:var(--text-xs);text-transform:uppercase;letter-spacing:.04em;white-space:nowrap}td{padding:var(--space-3) var(--space-4);color:var(--color-text-primary);border-top:1px solid var(--color-border)}tbody tr{transition:background-color var(--duration-fast) var(--ease-out)}tbody tr:hover{background:var(--color-border-subtle)}.timer-display{font-family:var(--font-mono);font-size:var(--text-sm);font-weight:var(--font-medium);color:var(--color-text-secondary);min-width:48px}.timer-display.urgent{color:var(--color-error);animation:pulse 1s var(--ease-in-out) infinite}@keyframes pulse{0%,to{opacity:1}50%{opacity:.6}}.confetti-container{pointer-events:none;z-index:var(--z-toast);position:fixed;inset:0;overflow:hidden}.confetti-piece{width:10px;height:10px;animation:linear forwards confettiFall;position:absolute}@keyframes confettiFall{0%{opacity:1;transform:translateY(-20px)rotate(0)}to{opacity:0;transform:translateY(100vh)rotate(720deg)}}.shortcut-row{padding:var(--space-2) 0;border-bottom:1px solid var(--color-border-subtle);justify-content:space-between;align-items:center;display:flex}.shortcut-row:last-child{border-bottom:none}.shortcut-desc{font-size:var(--text-sm);color:var(--color-text-secondary)}.shortcut-keys{gap:var(--space-1);display:flex}kbd{padding:2px var(--space-2);background:var(--color-border-subtle);border:1px solid var(--color-border);border-radius:var(--radius-sm);font-family:var(--font-mono);font-size:var(--text-xs);color:var(--color-text-secondary);border-bottom-width:2px;justify-content:center;align-items:center;min-width:24px;display:inline-flex}.subject-selector{gap:var(--space-2);padding-bottom:var(--space-2);margin-bottom:var(--space-6);scrollbar-width:none;display:none;overflow-x:auto}.subject-selector::-webkit-scrollbar{display:none}.subject-tab{align-items:center;gap:var(--space-2);padding:var(--space-2) var(--space-4);border-radius:var(--radius-full);font-size:var(--text-sm);font-weight:var(--font-semibold);white-space:nowrap;cursor:pointer;border:2px solid var(--color-border);background:var(--color-surface);color:var(--color-text-secondary);transition:border-color var(--duration-fast) var(--ease-out), background-color var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out), transform var(--duration-fast) var(--ease-spring);flex-shrink:0;font-family:inherit;display:flex}.subject-tab svg{flex-shrink:0;width:15px;height:15px}.subject-tab:hover{border-color:var(--color-primary);color:var(--color-primary);background:var(--color-primary-light);transform:translateY(-1px)}.subject-tab.active{border-color:var(--color-primary);background:var(--color-primary);color:#fff}.home-header{margin-bottom:var(--space-6)}.home-title{font-size:var(--text-3xl);font-weight:var(--font-bold);margin-bottom:var(--space-2)}.home-subtitle{font-size:var(--text-base);color:var(--color-text-secondary)}.mode-grid{gap:var(--space-4);margin-bottom:var(--space-8);grid-template-columns:repeat(auto-fill,minmax(200px,1fr));display:grid}.stats-bar{gap:var(--space-4);margin-bottom:var(--space-8);grid-template-columns:repeat(4,1fr);display:grid}@media (width<=640px){.stats-bar{grid-template-columns:repeat(2,1fr)}.mode-grid{grid-template-columns:1fr 1fr}}.stat-card{gap:var(--space-2);flex-direction:column;display:flex}.stat-card-icon{border-radius:var(--radius-lg);width:40px;height:40px;margin-bottom:var(--space-2);justify-content:center;align-items:center;display:flex}.stat-card-value{font-size:var(--text-3xl);font-weight:var(--font-bold);line-height:1}.stat-card-label{font-size:var(--text-sm);color:var(--color-text-secondary)}.stat-card-delta{font-size:var(--text-xs);font-weight:var(--font-medium);align-items:center;gap:2px;display:inline-flex}.stat-card-delta.up{color:var(--color-success)}.stat-card-delta.down{color:var(--color-error)}.empty-state{text-align:center;padding:var(--space-16) var(--space-8);justify-content:center;align-items:center;gap:var(--space-4);flex-direction:column;display:flex}.empty-state-icon{margin-bottom:var(--space-2);font-size:56px;line-height:1}.empty-state-title{font-size:var(--text-xl);font-weight:var(--font-semibold)}.empty-state-desc{font-size:var(--text-base);color:var(--color-text-secondary);max-width:360px}.settings-section{margin-bottom:var(--space-8)}.settings-section-title{font-size:var(--text-xs);font-weight:var(--font-semibold);color:var(--color-text-tertiary);text-transform:uppercase;letter-spacing:.08em;margin-bottom:var(--space-3)}.settings-row{justify-content:space-between;align-items:center;gap:var(--space-4);padding:var(--space-4) 0;border-bottom:1px solid var(--color-border-subtle);display:flex}.settings-row:last-child{border-bottom:none}.settings-row-left{flex:1;min-width:0}.settings-row-label{font-size:var(--text-sm);font-weight:var(--font-medium);color:var(--color-text-primary)}.settings-row-desc{font-size:var(--text-xs);color:var(--color-text-secondary);margin-top:2px}.quiz-layout{gap:var(--space-6);flex-direction:column;width:100%;max-width:640px;margin:0 auto;display:flex}.quiz-header{justify-content:space-between;align-items:center;gap:var(--space-4);display:flex}.quiz-controls{gap:var(--space-3);margin-top:var(--space-6);display:flex}.sr-only{clip:rect(0,0,0,0);white-space:nowrap;border-width:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}.truncate{text-overflow:ellipsis;white-space:nowrap;overflow:hidden}.flex{display:flex}.flex-col{flex-direction:column}.items-center{align-items:center}.justify-between{justify-content:space-between}.gap-2{gap:var(--space-2)}.gap-4{gap:var(--space-4)}.gap-6{gap:var(--space-6)}.flex-1{flex:1}.w-full{width:100%}.mt-2{margin-top:var(--space-2)}.mt-4{margin-top:var(--space-4)}.mt-6{margin-top:var(--space-6)}.mt-8{margin-top:var(--space-8)}.mb-2{margin-bottom:var(--space-2)}.mb-4{margin-bottom:var(--space-4)}.mb-6{margin-bottom:var(--space-6)}.text-sm{font-size:var(--text-sm)}.text-xs{font-size:var(--text-xs)}.text-secondary{color:var(--color-text-secondary)}.text-tertiary{color:var(--color-text-tertiary)}.font-semibold{font-weight:var(--font-semibold)}.font-bold{font-weight:var(--font-bold)}