:root {
  /* -- Colors -- */
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-accent: #facc15; /* A complementary yellow for highlights */

  --color-bg: #ffffff;
  --color-bg-alt: #111827; /* Dark charcoal, similar to a sophisticated black */
  --color-text: #1a1a1a;   /* Very dark gray, not pure black */
  --color-text-muted: #6b7280; /* Tailwind gray-500 */
  --color-border: #e5e7eb; /* Tailwind gray-200 */

  /* -- Typography -- */
  --font-heading: 'Outfit', 'Inter', -apple-system, system-ui, sans-serif; /* Outfit for bold headings */
  --font-body: 'Inter', -apple-system, system-ui, sans-serif;

  /* -- Layout -- */
  --max-width: 1280px; /* Slightly wider max-width for modern feel */
  --header-height: 4rem; /* For padding calculations */

  /* ── Standard Tokens (auto-injected) ── */
  --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: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  --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;
  --radius-default: 4px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  --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 10px 30px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
}

html { scroll-behavior: smooth; }
body { margin: 0; }

/* Base typography */
body { font-family: var(--font-body); line-height: 1.7; }
h1, h2, h3, h4, h5, h6 { font-family: var(--font-heading, var(--font-body)); line-height: 1.2; font-weight: 700; }

/* Sticky Header */
.site-header {
  background-color: rgba(255, 255, 255, 0.95); /* Light background for default visibility */
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm); /* Subtle shadow by default */
}
.site-header.is-scrolled {
  box-shadow: var(--shadow-md); /* Stronger shadow on scroll */
}

/* Mobile Nav Overlay */
.mobile-nav {
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out;
}
.mobile-nav.is-open {
  opacity: 1;
  visibility: visible;
}

/* Scroll Reveal Animations */
[data-reveal] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Staggered reveals for children */
[data-reveal-stagger] > * {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
[data-reveal-stagger].is-visible > *:nth-child(1) { transition-delay: 0ms; }
[data-reveal-stagger].is-visible > *:nth-child(2) { transition-delay: 100ms; }
[data-reveal-stagger].is-visible > *:nth-child(3) { transition-delay: 200ms; }
[data-reveal-stagger].is-visible > *:nth-child(4) { transition-delay: 300ms; }
[data-reveal-stagger].is-visible > *:nth-child(5) { transition-delay: 400ms; }
[data-reveal-stagger].is-visible > *:nth-child(6) { transition-delay: 500ms; }
[data-reveal-stagger].is-visible > *:nth-child(7) { transition-delay: 600ms; }
[data-reveal-stagger].is-visible > *:nth-child(8) { transition-delay: 700ms; }
[data-reveal-stagger].is-visible > *:nth-child(9) { transition-delay: 800ms; }
[data-reveal-stagger].is-visible > * { opacity: 1; transform: translateY(0); }

/* Icons */
.icon {
  display: inline-block;
  width: 1.25em;
  height: 1.25em;
  vertical-align: -0.15em;
  flex-shrink: 0;
}
.icon-sm { width: 1em; height: 1em; }
.icon-lg { width: 1.5em; height: 1.5em; }
.icon-xl { width: 2em; height: 2em; }

/* Reduced motion respect */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}