:root{--color-bg: #f8fafc;--color-surface: #ffffff;--color-foreground: #0f172a;--color-muted: #64748b;--color-muted-light: #94a3b8;--color-border: #e2e8f0;--color-border-light: #f1f5f9;--color-accent: #4f46e5;--color-accent-hover: #4338ca;--color-accent-light: #eef2ff;--color-sidebar-bg: #1e1b4b;--color-sidebar-fg: #e0e7ff;--color-sidebar-active: #4f46e5;--color-success: #059669;--color-success-light: #ecfdf5;--color-warning: #d97706;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 14px;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .05);--shadow-md: 0 1px 3px rgba(0, 0, 0, .08), 0 1px 2px rgba(0, 0, 0, .06);--shadow-lg: 0 4px 6px -1px rgba(0, 0, 0, .07), 0 2px 4px -2px rgba(0, 0, 0, .05);--transition: .15s ease}*,*:before,*:after{box-sizing:border-box}body{margin:0;background:var(--color-bg);color:var(--color-foreground);font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe 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8px}button{display:inline-flex;align-items:center;justify-content:center;gap:6px;border:1px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-surface);color:var(--color-foreground);cursor:pointer;font:inherit;font-size:13px;font-weight:500;padding:8px 16px;transition:background var(--transition),border-color var(--transition),box-shadow var(--transition);white-space:nowrap}button:hover{background:var(--color-bg);border-color:var(--color-muted-light)}button:active{transform:scale(.98)}.btn-primary{background:var(--color-accent);border-color:var(--color-accent);color:#fff}.btn-primary:hover{background:var(--color-accent-hover);border-color:var(--color-accent-hover)}.btn-success{background:var(--color-success);border-color:var(--color-success);color:#fff}.btn-success:hover{background:#047857;border-color:#047857}.btn-ghost{background:transparent;border-color:transparent;color:var(--color-muted)}.btn-ghost:hover{background:var(--color-bg);color:var(--color-foreground)}.btn-sm{font-size:12px;padding:5px 10px}textarea,input[type=text],input[type=search]{border:1px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-surface);color:var(--color-foreground);font:inherit;font-size:14px;padding:10px 14px;width:100%;transition:border-color var(--transition),box-shadow 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p{font-size:13px;color:var(--color-muted);line-height:1.6;margin:0}.update-badge{display:inline-flex;align-items:center;gap:6px;background:var(--color-success-light);color:var(--color-success);font-size:12px;font-weight:600;padding:6px 12px;border-radius:20px;margin-top:8px}.placeholder-grid{display:grid;gap:20px;grid-template-columns:repeat(auto-fill,minmax(280px,1fr))}.placeholder-card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-lg);padding:28px;transition:box-shadow var(--transition)}.placeholder-card:hover{box-shadow:var(--shadow-lg)}.placeholder-card .card-icon{width:44px;height:44px;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:20px;margin-bottom:16px}.placeholder-card h3{font-size:15px;font-weight:600;margin:0 0 8px;color:var(--color-foreground)}.placeholder-card 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