/* ============================================
   TechJapan Design System - Dark Tech Theme
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Colors */
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-tertiary: #1a1a2e;
  --bg-card: rgba(18, 18, 26, 0.8);
  --bg-glass: rgba(18, 18, 26, 0.6);

  --text-primary: #ffffff;
  --text-secondary: #e8e8ed;
  --text-muted: #8888a0;
  --text-dim: #555570;

  --accent-cyan: #ff5035;
  --accent-cyan-rgb: 255, 80, 53;
  --accent-purple: #7c5cff;
  --accent-purple-rgb: 124, 92, 255;
  --accent-green: #00ff88;
  --accent-green-rgb: 0, 255, 136;
  --accent-orange: #ff6b35;

  --gradient-primary: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
  --gradient-hero: linear-gradient(135deg, #0a0a0f 0%, #12121a 50%, #0f0f2a 100%);
  --gradient-card-border: linear-gradient(135deg, rgba(255, 80, 53, 0.3), rgba(124, 92, 255, 0.3));

  /* Typography */
  --font-heading: 'Inter', 'Noto Sans JP', sans-serif;
  --font-body: 'Inter', 'Noto Sans JP', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --fs-hero: clamp(2.5rem, 5vw, 4rem);
  --fs-h1: clamp(2rem, 4vw, 3rem);
  --fs-h2: clamp(1.5rem, 3vw, 2.25rem);
  --fs-h3: clamp(1.25rem, 2.5vw, 1.75rem);
  --fs-h4: 1.25rem;
  --fs-body: 1rem;
  --fs-small: 0.875rem;
  --fs-xs: 0.75rem;

  --lh-heading: 1.3;
  --lh-body: 1.8;

  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;
  --space-4xl: 8rem;

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 800px;
  --header-height: 72px;

  /* Effects */
  --border-radius-sm: 8px;
  --border-radius-md: 12px;
  --border-radius-lg: 16px;
  --border-radius-xl: 24px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow-cyan: 0 0 20px rgba(255, 80, 53, 0.15);
  --shadow-glow-purple: 0 0 20px rgba(124, 92, 255, 0.15);

  --transition-fast: 0.15s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;

  --glass-blur: blur(12px);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: var(--lh-body);
  color: var(--text-secondary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Grid Background */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 80, 53, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 80, 53, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: 0;
}

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

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

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

ul, ol {
  list-style: none;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--text-primary);
  line-height: var(--lh-heading);
  font-weight: 700;
}

h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }
h4 { font-size: var(--fs-h4); }

p {
  margin-bottom: var(--space-sm);
}

.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
  position: relative;
  z-index: 1;
}

.container--narrow {
  max-width: var(--container-narrow);
}

.section {
  padding: var(--space-4xl) 0;
  position: relative;
}

.section--dark {
  background-color: var(--bg-secondary);
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.section__label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-bottom: var(--space-sm);
}

.section__title {
  font-size: var(--fs-h2);
  margin-bottom: var(--space-md);
}

.section__subtitle {
  color: var(--text-muted);
  font-size: 1.125rem;
  max-width: 640px;
  margin: 0 auto;
}

/* --- Grid --- */
.grid {
  display: grid;
  gap: var(--space-lg);
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

/* --- Utilities --- */
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.flex-col { flex-direction: column; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

.text-center { text-align: center; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }

/* --- Scroll Animations --- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }

/* --- Selection --- */
::selection {
  background: rgba(255, 80, 53, 0.3);
  color: var(--text-primary);
}

/* --- Scrollbar --- */
::-webkit-scrollbar {
  width: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--bg-tertiary);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-dim);
}