:root {
  /* Sierra Circuits / ProtoExpress palette */
  --color-white: #ffffff;
  --color-gray-50: #f5f5f5;
  --color-gray-100: #ebebeb;
  --color-gray-200: #d9d9d9;
  --color-gray-300: #bdbdbd;
  --color-gray-600: #666666;
  --color-gray-800: #444444;
  --color-text: #222222;
  --color-text-muted: #666666;
  --color-text-light: #888888;

  --color-nav-dark: #1d2330;
  --color-nav-darker: #151a24;

  --color-yellow: #f4c116;
  --color-yellow-dark: #d4a810;
  --color-orange: #ffb300;
  --color-blue: #2f5ea7;
  --color-blue-dark: #244a85;
  --color-green: #3fae2a;
  --color-green-dark: #358f23;

  --color-bg-primary: #ffffff;
  --color-bg-secondary: #f5f5f5;
  --color-bg-elevated: #ffffff;
  --color-bg-alt: #f5f5f5;

  --color-text-primary: #222222;
  --color-text-secondary: #444444;
  --color-text-tertiary: #666666;
  --color-text-on-dark: #ffffff;
  --color-text-on-dark-muted: rgba(255, 255, 255, 0.75);

  --color-accent: #f4c116;
  --color-accent-bright: #ffb300;
  --color-accent-blue: #2f5ea7;
  --color-accent-green: #3fae2a;
  --color-accent-dim: rgba(244, 193, 22, 0.12);

  --color-border: #e0e0e0;
  --color-border-dark: #d0d0d0;
  --color-border-accent: #f4c116;

  --gradient-hero-overlay: linear-gradient(90deg, rgba(29, 35, 48, 0.92) 0%, rgba(29, 35, 48, 0.75) 45%, rgba(29, 35, 48, 0.35) 100%);
  --gradient-accent: linear-gradient(135deg, #f4c116 0%, #ffb300 100%);
  --gradient-text: linear-gradient(135deg, #2f5ea7 0%, #244a85 100%);
  --gradient-card: linear-gradient(180deg, #ffffff 0%, #fafafa 100%);

  /* Typography */
  --font-sans: "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: Consolas, "Courier New", monospace;

  --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;
  --text-5xl: 3rem;
  --text-hero: clamp(2rem, 1.5rem + 2.5vw, 3.25rem);

  --leading-tight: 1.15;
  --leading-snug: 1.3;
  --leading-normal: 1.6;
  --leading-relaxed: 1.75;

  --tracking-tight: -0.02em;
  --tracking-normal: 0;
  --tracking-wide: 0.04em;
  --tracking-wider: 0.08em;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --container-max: 1280px;
  --container-narrow: 960px;
  --topbar-height: 0px;
  --header-main-height: 0px;
  --nav-height: 52px;
  --header-total: var(--nav-height);
  --section-padding-y: clamp(2.5rem, 3.5vw, 3.5rem);

  /* Effects */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --duration-fast: 150ms;
  --duration-normal: 250ms;
  --duration-slow: 400ms;

  /* Z-index */
  --z-nav: 100;
  --z-overlay: 200;
}