/* === Color & Typography Variables === */
:root {
  /* Primary palette */
  --color-primary: #1976D2;       /* Bright blue */
  --color-primary-dark: #1565C0;
  --color-primary-light: #42A5F5;

  /* Secondary palette */
  --color-secondary: #0D3B66;     /* Deep navy */
  --color-secondary-dark: #0A2744;
  --color-secondary-light: #1A5276;

  /* Neutrals */
  --color-bg: #F7F9FC;            /* Cool white */
  --color-bg-alt: #EDF1F7;
  --color-surface: #FFFFFF;
  --color-text: #2C2C2C;
  --color-text-light: #5A6577;
  --color-text-lighter: #8C95A4;
  --color-border: #D4DAE3;
  --color-border-light: #E6EAF0;

  /* Functional */
  --color-success: #40916C;
  --color-error: #C0392B;

  /* Typography */
  --font-body: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --font-heading: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", 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: 2rem;
  --text-4xl: 2.5rem;

  --leading-tight: 1.3;
  --leading-normal: 1.6;
  --leading-relaxed: 1.8;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --nav-height: 72px;

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* Shadow */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
}