/* ============================================
   KOREA DECODE — Global CSS
   Variables, Reset, Typography, Animations
   ============================================ */

/* --- CSS Variables --- */
:root {
  /* Colors */
  --accent: #CCFF00;
  --accent-dim: rgba(204, 255, 0, 0.15);
  --accent-hover: #e0ff4d;
  --bg-main: #000;
  --bg-sec: #111;
  --bg-card: #1a1a1a;
  --bg-card-hover: #222;
  --border: #333;
  --border-light: #444;
  --text-primary: #fff;
  --text-secondary: #aaa;
  --text-muted: #666;
  --danger: #ff4444;
  --success: #44ff88;
  --warning: #ffaa44;

  /* Typography */
  --font-display: 'Syncopate', sans-serif;
  --font-body: 'Space Grotesk', sans-serif;
  --font-reading: 'Inter', sans-serif;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;

  /* Layout */
  --max-width: 1200px;
  --max-width-narrow: 800px;
  --header-height: 64px;
  --radius: 8px;
  --radius-lg: 16px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition: 250ms ease;
  --transition-slow: 400ms ease;
}

/* --- Reset --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  background: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, video {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--accent-hover);
}

ul, ol {
  list-style: none;
}

button, input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
  border: none;
  outline: none;
  background: none;
}

button {
  cursor: pointer;
}

/* --- Typography --- */
h1, h2, h3 {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: 0.02em;
  line-height: 1.2;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.5rem); }
h3 { font-size: clamp(1.1rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.1rem; font-weight: 600; }

p {
  font-family: var(--font-reading);
  line-height: 1.8;
  color: var(--text-secondary);
}

.accent { color: var(--accent); }
.text-muted { color: var(--text-muted); }

/* --- Utility --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container-narrow {
  width: 100%;
  max-width: var(--max-width-narrow);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.section {
  padding: var(--space-3xl) 0;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--bg-main);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--border-light);
}

/* --- Selection --- */
::selection {
  background: var(--accent);
  color: var(--bg-main);
}

/* --- Animations --- */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.fade-in { animation: fadeIn var(--transition-slow) ease both; }
.fade-in-up { animation: fadeInUp var(--transition-slow) ease both; }

/* Staggered animation delays */
.delay-1 { animation-delay: 100ms; }
.delay-2 { animation-delay: 200ms; }
.delay-3 { animation-delay: 300ms; }
.delay-4 { animation-delay: 400ms; }

/* --- Loading skeleton --- */
.skeleton {
  background: linear-gradient(90deg, var(--bg-card) 25%, var(--bg-card-hover) 50%, var(--bg-card) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: var(--radius);
}

@keyframes skeleton-shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* --- Print --- */
@media print {
  body { background: #fff; color: #000; }
  .no-print { display: none !important; }
}