:root{--primary-color: #fb923c;--primary-hover: #f97316;--bg-color: #fffbeb;--sidebar-bg: #fff7ed;--card-bg: #ffffff;--text-main: #374151;--text-muted: #6b7280;--math-color: #3b82f6;--science-color: #10b981;--english-color: #8b5cf6;--border-color: #ffedd5}body{margin:0;font-family:PingFang SC,Microsoft YaHei,sans-serif;background-color:var(--bg-color);color:var(--text-main)}.app-container{display:flex;min-height:100vh}.sidebar{width:260px;background-color:var(--sidebar-bg);border-right:2px solid 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var(--border-color)}.stat-icon-box{padding:12px;border-radius:16px;color:#fff}.stat-icon-box.orange{background-color:var(--primary-color)}.stat-icon-box.blue{background-color:var(--math-color)}.stat-icon-box.green{background-color:var(--science-color)}.stat-info{display:flex;flex-direction:column}.stat-label{font-size:13px;color:var(--text-muted)}.stat-value{font-size:22px;font-weight:800;color:var(--text-main)}.checkin-btn{margin-left:auto;background-color:var(--primary-color);color:#fff;border:none;border-radius:12px;padding:8px 12px;font-size:12px;font-weight:700;cursor:pointer;transition:all .2s}.checkin-btn:hover:not(:disabled){background-color:var(--primary-hover)}.checkin-btn.checked{background-color:#e2e8f0;color:#94a3b8;cursor:not-allowed}.dashboard-main-grid{display:grid;grid-template-columns:2fr 1fr;gap:24px;margin-bottom:30px}.dashboard-chart-card,.quick-actions-card{background-color:#fff;border-radius:24px;padding:24px;box-shadow:0 4px 6px -1px #0000000d;border:2px solid 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