:root {
  /* ── Brand Colors ── */
  --color-brand-blue: #4B8BF5;
  --color-brand-blue-light: #6BA3F7;
  --color-brand-teal: #0891B2;
  --color-brand-green: #10B981;

  /* ── Navy / Slate Scale ── */
  --color-navy-900: #0F172A;
  --color-navy-800: #1E293B;
  --color-navy-700: #334155;
  --color-slate-600: #475569;
  --color-slate-500: #64748B;
  --color-slate-400: #94A3B8;
  --color-slate-300: #CBD5E1;
  --color-slate-200: #E2E8F0;
  --color-gray-100: #F1F5F9;
  --color-gray-50: #F8FAFC;
  --color-white: #FFFFFF;

  /* ── Specialty Suite Colors ── */
  --color-ophth: #7C3AED;
  --color-onc: #DC2626;
  --color-neuro: #1D4ED8;
  --color-immuno: #0891B2;
  --color-cardio: #C2410C;

  /* ── Gradients ── */
  --gradient-hero: linear-gradient(135deg, #0F172A 0%, #1E293B 100%);
  --gradient-accent: linear-gradient(135deg, #4B8BF5, #0891B2, #10B981);
  --gradient-text: linear-gradient(90deg, #4B8BF5, #0891B2, #10B981);
  --gradient-cta: linear-gradient(135deg, #1E40AF, #0891B2);
  --gradient-card-hover: linear-gradient(135deg, rgba(75,139,245,0.08), rgba(8,145,178,0.08));

  /* ── Typography ── */
  --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', monospace;

  /* ── Spacing ── */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  --space-2xl: 64px;
  --space-3xl: 96px;
  --space-4xl: 128px;

  /* ── Layout ── */
  --container-max: 1200px;
  --container-wide: 1400px;
  --container-narrow: 800px;

  /* ── Border Radius ── */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* ── Shadows ── */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.12);

  /* ── Transitions ── */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;
}