/* Base theme variables - shared across all themes */
:root {
  /* Border Radius */
  --theme-radius-sm: 0.125rem;
  --theme-radius-md: 0.375rem;
  --theme-radius-lg: 0.5rem;
  --theme-radius-xl: 0.75rem;
  --theme-radius-full: 9999px;
  
  /* Typography Scale */
  --theme-font-xs: 0.75rem;
  --theme-font-sm: 0.875rem;
  --theme-font-base: 1rem;
  --theme-font-lg: 1.125rem;
  --theme-font-xl: 1.25rem;
  --theme-font-2xl: 1.5rem;
  --theme-font-3xl: 1.875rem;
  --theme-font-4xl: 2.25rem;
  
  /* Line Heights */
  --theme-leading-none: 1;
  --theme-leading-tight: 1.25;
  --theme-leading-snug: 1.375;
  --theme-leading-normal: 1.5;
  --theme-leading-relaxed: 1.625;
  --theme-leading-loose: 2;
  
  /* Font Weights */
  --theme-font-thin: 100;
  --theme-font-light: 300;
  --theme-font-normal: 400;
  --theme-font-medium: 500;
  --theme-font-semibold: 600;
  --theme-font-bold: 700;
  --theme-font-extrabold: 800;
  --theme-font-black: 900;
  
  /* Spacing Scale */
  --theme-space-px: 1px;
  --theme-space-0: 0;
  --theme-space-1: 0.25rem;
  --theme-space-2: 0.5rem;
  --theme-space-3: 0.75rem;
  --theme-space-4: 1rem;
  --theme-space-5: 1.25rem;
  --theme-space-6: 1.5rem;
  --theme-space-8: 2rem;
  --theme-space-10: 2.5rem;
  --theme-space-12: 3rem;
  --theme-space-16: 4rem;
  --theme-space-20: 5rem;
  --theme-space-24: 6rem;
  --theme-space-32: 8rem;
  
  /* Interactive States */
  --theme-focus-ring-offset: 2px;
  
  /* Transitions */
  --theme-transition-fast: 150ms ease-in-out;
  --theme-transition-normal: 300ms ease-in-out;
  --theme-transition-slow: 500ms ease-in-out;
  
  /* Responsive Breakpoints */
  --theme-mobile-max: 767px;
  --theme-tablet-min: 768px;
  --theme-tablet-max: 1023px;
  --theme-desktop-min: 1024px;
  
  /* Component Specific Variables */
  --theme-header-height-mobile: 41px;
  --theme-header-height-desktop: 56px;
  --theme-nav-height: 48px;
  --theme-card-shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1);
  --theme-card-shadow-hover: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --theme-book-card-width: 180px;
  --theme-book-card-height: 248px;
  --theme-author-card-min-height: 250px;
  --theme-author-card-mobile-height: 422px;
  
  /* Header-specific styles */
  --theme-header-container-padding: 14px;
  --theme-search-border-radius: 69px;
  --theme-search-height: 33px;
  --theme-logo-width-mobile: 76px;
  --theme-logo-width-desktop: 130px;
  
  /* Navigation specific */
  --theme-nav-link-padding: 12px 16px;
  --theme-nav-bg: #ffffff;
  --theme-nav-border: #f3f4f6;
}