:root {
  --brand: #2563eb;
  --brand-600: #1d4ed8;
  --brand-50: #eff6ff;
  --bg: #f4f6fa;
  --surface: #ffffff;
  --surface-2: #fafbfc;
  --text: #1f2937;
  --text-2: #6b7280;
  --text-3: #9ca3af;
  --border: #e5e7eb;
  --border-2: #d1d5db;
  --tone-success: #16a34a;
  --tone-success-bg: #dcfce7;
  --tone-info: #2563eb;
  --tone-info-bg: #dbeafe;
  --tone-warn: #d97706;
  --tone-warn-bg: #fef3c7;
  --tone-danger: #dc2626;
  --tone-danger-bg: #fee2e2;
  --tone-muted: #6b7280;
  --tone-muted-bg: #f3f4f6;
  --tone-ops: #7c3aed;
  --tone-ops-bg: #ede9fe;
  --tone-default: #9ca3af;
  --tone-default-bg: #f3f4f6;
  --radius: 10px;
  --radius-sm: 6px;
  --radius-lg: 14px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 4px 12px rgba(15, 23, 42, .05);
  --shadow-md: 0 2px 6px rgba(15, 23, 42, .06), 0 8px 24px rgba(15, 23, 42, .08);
  --shadow-lg: 0 16px 48px rgba(15, 23, 42, .20);
  --sidebar-w: 220px;
  --topbar-h: 56px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --ring: 0 0 0 3px var(--brand-50);

  /* ===== 科技感增强（2026-08-17）===== */
  --brand-grad: linear-gradient(135deg, #3b82f6 0%, #2563eb 55%, #4f46e5 100%);
  --brand-glow: 0 8px 22px rgba(37, 99, 235, .35);
  --accent: #38bdf8;
  --accent-grad: linear-gradient(135deg, #22d3ee, #3b82f6);
  --sidebar-bg: linear-gradient(180deg, #0f172a 0%, #131d38 55%, #0d1426 100%);
  --sidebar-active: linear-gradient(90deg, rgba(59, 130, 246, .28), rgba(59, 130, 246, .04));
  --sidebar-glow: 0 0 0 1px rgba(56, 189, 248, 0);
  --surface-border: rgba(15, 23, 42, .07);
  --content-bg:
    radial-gradient(1100px 480px at 100% -8%, rgba(56, 189, 248, .07), transparent 60%),
    radial-gradient(1000px 520px at -8% 4%, rgba(99, 102, 241, .06), transparent 55%),
    #f4f6fa;
  --stat-grad: linear-gradient(135deg, #f8fafc 0%, #eef2ff 100%);
  --stat-grad-2: linear-gradient(135deg, #ecfeff 0%, #eff6ff 100%);
  --radius-xl: 16px;
  --shadow-glow: 0 10px 30px rgba(37, 99, 235, .10);
  --hairline: 1px solid rgba(15, 23, 42, .06);
  --collapse-w: 68px;
}