/**
 * CSS Variables for Theme Customization
 * 
 * Define all theme colors, spacing, typography here.
 * When switching Bootstrap versions, update these variables
 * instead of changing values throughout your CSS.
 */

:root {
  /* ============================================
     COLORS
     ============================================ */
  
  /* Primary colors */
  --color-primary: #007bff;
  --color-secondary: #6c757d;
  --color-success: #28a745;
  --color-info: #17a2b8;
  --color-warning: #ffc107;
  --color-danger: #dc3545;
  --color-light: #f8f9fa;
  --color-dark: #343a40;
  
  /* Brand colors */
  --color-brand-primary: #007bff;
  --color-brand-secondary: #6c757d;
  
  /* Text colors */
  --color-text-primary: #212529;
  --color-text-secondary: #6c757d;
  --color-text-muted: #6c757d;
  --color-text-white: #fff;
  
  /* Background colors */
  --color-bg-body: #fff;
  --color-bg-light: #f8f9fa;
  --color-bg-dark: #343a40;
  
  /* Border colors */
  --color-border: #dee2e6;
  --color-border-light: #e9ecef;
  --color-border-dark: #adb5bd;
  
  /* Link colors */
  --color-link: #007bff;
  --color-link-hover: #0056b3;
  
  /* ============================================
     SPACING
     ============================================ */
  
  --spacing-xs: 0.25rem;   /* 4px */
  --spacing-sm: 0.5rem;    /* 8px */
  --spacing-md: 1rem;      /* 16px */
  --spacing-lg: 1.5rem;    /* 24px */
  --spacing-xl: 2rem;      /* 32px */
  --spacing-xxl: 3rem;     /* 48px */
  
  /* Form spacing */
  --form-group-margin: 1rem;
  --form-label-margin: 0.5rem;
  --form-control-padding-y: 0.375rem;
  --form-control-padding-x: 0.75rem;
  
  /* ============================================
     TYPOGRAPHY
     ============================================ */
  
  /* Font families */
  --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-family-monospace: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  /* Font sizes */
  --font-size-base: 1rem;      /* 16px */
  --font-size-xs: 0.75rem;     /* 12px */
  --font-size-sm: 0.875rem;    /* 14px */
  --font-size-lg: 1.25rem;     /* 20px */
  --font-size-xl: 1.5rem;      /* 24px */
  
  /* Headings */
  --font-size-h1: 2.5rem;      /* 40px */
  --font-size-h2: 2rem;        /* 32px */
  --font-size-h3: 1.75rem;     /* 28px */
  --font-size-h4: 1.5rem;      /* 24px */
  --font-size-h5: 1.25rem;     /* 20px */
  --font-size-h6: 1rem;        /* 16px */
  
  /* Line heights */
  --line-height-base: 1.5;
  --line-height-sm: 1.25;
  --line-height-lg: 2;
  
  /* Font weights */
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* ============================================
     BORDERS
     ============================================ */
  
  --border-width: 1px;
  --border-radius: 0.25rem;
  --border-radius-sm: 0.2rem;
  --border-radius-lg: 0.3rem;
  --border-radius-pill: 50rem;
  
  /* ============================================
     SHADOWS
     ============================================ */
  
  --shadow-sm: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
  --shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 1rem 3rem rgba(0, 0, 0, 0.175);
  
  /* ============================================
     GRID & LAYOUT
     ============================================ */
  
  --grid-gutter-width: 1.5rem;
  --container-max-width-sm: 540px;
  --container-max-width-md: 720px;
  --container-max-width-lg: 960px;
  --container-max-width-xl: 1140px;
  --container-max-width-xxl: 1320px;
  
  /* ============================================
     BREAKPOINTS
     ============================================ */
  
  --breakpoint-xs: 0;
  --breakpoint-sm: 576px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 992px;
  --breakpoint-xl: 1200px;
  --breakpoint-xxl: 1400px;
  
  /* ============================================
     TRANSITIONS
     ============================================ */
  
  --transition-base: all 0.2s ease-in-out;
  --transition-fade: opacity 0.15s linear;
  --transition-collapse: height 0.35s ease;
  
  /* ============================================
     Z-INDEX
     ============================================ */
  
  --z-index-dropdown: 1000;
  --z-index-sticky: 1020;
  --z-index-fixed: 1030;
  --z-index-modal-backdrop: 1040;
  --z-index-modal: 1050;
  --z-index-popover: 1060;
  --z-index-tooltip: 1070;
  
  /* ============================================
     COMPONENT SPECIFIC
     ============================================ */
  
  /* Buttons */
  --btn-padding-y: 0.375rem;
  --btn-padding-x: 0.75rem;
  --btn-font-size: 1rem;
  --btn-border-radius: 0.25rem;
  
  /* Forms */
  --input-padding-y: 0.375rem;
  --input-padding-x: 0.75rem;
  --input-font-size: 1rem;
  --input-border-color: #ced4da;
  --input-border-radius: 0.25rem;
  --input-focus-border-color: #80bdff;
  --input-focus-box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
  
  /* Tables */
  --table-cell-padding: 0.75rem;
  --table-border-color: #dee2e6;
  
  /* Alerts */
  --alert-padding-y: 0.75rem;
  --alert-padding-x: 1.25rem;
  --alert-border-radius: 0.25rem;
  
  /* Cards */
  --card-spacer-y: 0.75rem;
  --card-spacer-x: 1.25rem;
  --card-border-width: 1px;
  --card-border-radius: 0.25rem;
  --card-border-color: rgba(0, 0, 0, 0.125);
}