/**
 * CSS Variables (Custom Properties)
 * テーマカラー、サイズ、間隔などをグローバル変数として定義
 */

/* Google Fonts - Noto Sans JP */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&display=swap');

:root {
  /* ========================================
     Color Palette
     ======================================== */
  
  /* Primary Colors */
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-primary-dark: #1e40af;
  --color-primary-50: #eff6ff;
  --color-primary-100: #dbeafe;
  --color-primary-600: #2563eb;
  --color-primary-700: #1d4ed8;
  
  /* Secondary Colors */
  --color-secondary: #64748b;
  --color-secondary-light: #94a3b8;
  --color-secondary-dark: #475569;
  
  /* Neutral Colors */
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-gray-900: #111827;
  
  /* State Colors */
  --color-success: #10b981;
  --color-success-light: #34d399;
  --color-success-dark: #059669;
  --color-warning: #f59e0b;
  --color-warning-light: #fbbf24;
  --color-warning-dark: #d97706;
  --color-danger: #ef4444;
  --color-danger-light: #f87171;
  --color-danger-dark: #dc2626;
  --color-info: #06b6d4;
  --color-info-light: #22d3ee;
  --color-info-dark: #0891b2;
  
  /* Background Colors */
  --bg-body: #ffffff;
  --bg-surface: #ffffff;
  --bg-overlay: rgba(0, 0, 0, 0.5);
  
  /* Text Colors */
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #9ca3af;
  --text-white: #ffffff;
  
  /* Border Colors */
  --border-color: #e5e7eb;
  --border-color-dark: #d1d5db;
  
  /* ========================================
     Typography
     ======================================== */
  
  --font-family-base: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI', 
                       Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-family-mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
  
  --font-size-xs: 0.75rem;      /* 12px */
  --font-size-sm: 0.875rem;     /* 14px */
  --font-size-base: 1rem;       /* 16px */
  --font-size-lg: 1.125rem;     /* 18px */
  --font-size-xl: 1.25rem;      /* 20px */
  --font-size-2xl: 1.5rem;      /* 24px */
  --font-size-3xl: 1.875rem;    /* 30px */
  --font-size-4xl: 2.25rem;     /* 36px */
  
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;
  
  /* ========================================
     Spacing
     ======================================== */
  
  --spacing-1: 0.25rem;   /* 4px */
  --spacing-2: 0.5rem;    /* 8px */
  --spacing-3: 0.75rem;   /* 12px */
  --spacing-4: 1rem;      /* 16px */
  --spacing-5: 1.25rem;   /* 20px */
  --spacing-6: 1.5rem;    /* 24px */
  --spacing-8: 2rem;      /* 32px */
  --spacing-10: 2.5rem;   /* 40px */
  --spacing-12: 3rem;     /* 48px */
  --spacing-16: 4rem;     /* 64px */
  --spacing-20: 5rem;     /* 80px */
  
  /* ========================================
     Border Radius
     ======================================== */
  
  --radius-sm: 0.25rem;   /* 4px */
  --radius-base: 0.5rem;  /* 8px */
  --radius-lg: 0.75rem;   /* 12px */
  --radius-xl: 1rem;      /* 16px */
  --radius-full: 9999px;  /* circular */
  
  /* ========================================
     Shadows
     ======================================== */
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-base: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  
  /* ========================================
     Transitions
     ======================================== */
  
  --transition-fast: 150ms ease-in-out;
  --transition-base: 200ms ease-in-out;
  --transition-slow: 300ms ease-in-out;
  
  /* ========================================
     Z-Index
     ======================================== */
  
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  
  /* ========================================
     Breakpoints (for reference in JS)
     ======================================== */
  
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;
  
  /* ========================================
     Container
     ======================================== */
  
  --container-max-width: 1600px; /* 1280px → 1600px に拡張 */
  --container-padding: var(--spacing-4);
}

/* Dark mode support (optional) */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-body: #ffffff;
    --bg-surface: #ffffff;
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --text-muted: #9ca3af;
    --border-color: #e5e7eb;
    --border-color-dark: #d1d5db;
  }
}