/* CSS Variables defining Light & Bridge premium design tokens */
:root {
  --color-primary: #0A1628;       /* Midnight Navy */
  --color-primary-soft: #1A2942;  /* Deep Navy */
  --color-surface: #F5F1E8;       /* Ivory White */
  --color-accent-gold: #D4A574;   /* Warm Gold */
  --color-accent-gold-soft: #E8B560; /* Soft Amber */
  --color-accent-blue: #4A6B8A;   /* Steel Blue */
  --color-text-body: #3A4654;     /* Slate Gray */
  --color-text-muted: #8A8478;    /* Stone Gray */

  --font-serif-en: 'Playfair Display', serif;
  --font-serif-ko: 'Noto Serif KR', serif;
  --font-sans-en: 'Inter', sans-serif;
  --font-sans-ko: 'Pretendard', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --font-quote: 'Cormorant Garamond', serif;
}

/* Global Styles & Resets */
html {
  scroll-behavior: smooth;
  background-color: var(--color-primary);
  color: var(--color-surface);
  font-family: var(--font-sans-en), var(--font-sans-ko), sans-serif;
  -webkit-font-smoothing: antialiased;
}

body {
  overflow-x: hidden;
  margin: 0;
  padding: 0;
  line-height: 1.7;
}

/* Custom Premium Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--color-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--color-primary-soft);
  border: 2px solid var(--color-primary);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--color-accent-gold);
}

/* Focus States Accessibility */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--color-accent-gold);
  outline-offset: 2px;
}

/* Typography Setup & Scale */
.font-title {
  font-family: var(--font-serif-en), var(--font-serif-ko), serif;
  letter-spacing: -0.02em;
}

.font-body {
  font-family: var(--font-sans-en), var(--font-sans-ko), sans-serif;
}

.font-mono-num {
  font-family: var(--font-mono), monospace;
}

.font-italic-quote {
  font-family: var(--font-quote), serif;
  font-style: italic;
}

/* Custom Gradients & Ambient Glow */
.hero-gradient {
  background: linear-gradient(135deg, #0A1628 0%, #1A2942 50%, #2D4159 100%);
}

.ambient-light-beam {
  position: absolute;
  top: 0;
  right: 0;
  width: 60%;
  height: 80vh;
  background: radial-gradient(circle at top right, rgba(212, 165, 116, 0.12), transparent 70%);
  pointer-events: none;
  z-index: 1;
  animation: pulse-light 8s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}

@keyframes pulse-light {
  0%, 100% {
    opacity: 0.8;
    transform: scale(1);
  }
  50% {
    opacity: 1.2;
    transform: scale(1.05);
  }
}

/* Card Glow Effect (Dark sections) */
.premium-card-dark {
  background: var(--color-primary-soft);
  border: 1px solid rgba(212, 165, 116, 0.1);
  transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
.premium-card-dark:hover {
  border-color: rgba(212, 165, 116, 0.3);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

/* Card Lift Effect (Light sections) */
.premium-card-light {
  background: #FFF;
  border: 1px solid rgba(58, 70, 84, 0.06);
  transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
.premium-card-light:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(58, 70, 84, 0.08);
}

/* Animated Elements on Scroll (Intersection Observer classes) */
.reveal-on-scroll {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal-on-scroll.revealed {
  opacity: 1;
  transform: translateY(0);
}

.delay-100 { transition-delay: 100ms; }
.delay-200 { transition-delay: 200ms; }
.delay-300 { transition-delay: 300ms; }
.delay-400 { transition-delay: 400ms; }
.delay-500 { transition-delay: 500ms; }

/* Custom Underlines & Highlights */
.gold-underline {
  position: relative;
  display: inline-block;
}
.gold-underline::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent-gold);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.gold-underline:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* Global 3-Hub Network Line Pulse */
@keyframes dash-pulse {
  to {
    stroke-dashoffset: -40;
  }
}
.pulse-connector {
  stroke-dasharray: 8 4;
  animation: dash-pulse 2s linear infinite;
}

/* Respect user's system setting for motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto !important;
  }
  .reveal-on-scroll {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  .ambient-light-beam {
    animation: none !important;
  }
  .pulse-connector {
    animation: none !important;
  }
}