:root {
  /* Colors */
  --color-bg:           #FFFFFF;
  --color-bg-subtle:    #F9FAFB;
  --color-bg-muted:     #F3F4F6;
  --color-text:         #111827;
  --color-text-muted:   #6B7280;
  --color-text-subtle:  #9CA3AF;
  --color-accent:       #1976D2;
  --color-accent-dark:  #1565C0;
  --color-accent-light: #E3F2FD;
  --color-border:       #E5E7EB;
  --color-border-dark:  #D1D5DB;

  /* Tag colors */
  --tag-medicine-bg:    #E8F5E9;
  --tag-medicine-text:  #2E7D32;
  --tag-investing-bg:   #FFF3E0;
  --tag-investing-text: #E65100;
  --tag-tech-bg:        #E3F2FD;
  --tag-tech-text:      #1565C0;
  --tag-life-bg:        #F3E5F5;
  --tag-life-text:      #6A1B9A;

  /* Typography */
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;

  --weight-regular:  400;
  --weight-medium:   500;
  --weight-semibold: 600;
  --weight-bold:     700;

  /* Spacing (4px grid) */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --max-content: 768px;
  --max-wide:    1100px;
  --max-site:    1280px;

  --radius-sm:   4px;
  --radius-md:   8px;
  --radius-lg:   12px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-xs: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);

  /* Transitions */
  --t-fast: 150ms ease;
  --t-base: 200ms ease;
}