:root {
  /* Colors */
  --primary: #1a5fc7;
  --primary-dark: #0d47a1;
  --primary-light: #e8f0fe;
  --accent: #ff6b35;
  --accent-hover: #e55a2b;
  --dark-bg: #1a1a2e;
  --dark-bg-lighter: #252542;
  --text: #333333;
  --text-secondary: #666666;
  --text-light: #999999;
  --light-bg: #f8f9fa;
  --white: #ffffff;
  --border: #e0e0e0;
  
  /* Typography */
  --font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-size-base: 16px;
  --font-size-sm: 14px;
  --font-size-lg: 18px;
  --font-size-xl: 24px;
  --font-size-2xl: 32px;
  --font-size-3xl: 42px;
  --font-size-4xl: 56px;
  --line-height: 1.6;
  
  /* Spacing */
  --section-padding: 80px 0;
  --container-max: 1200px;
  --container-padding: 0 20px;
  
  /* Effects */
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.15);
  --shadow-header: 0 2px 10px rgba(0,0,0,0.08);
  --shadow-header-scrolled: 0 4px 20px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --transition: all 0.3s ease;
}