/* ============================================
   ZLTAC – Mobile-First Responsive Stylesheet
   ============================================ */

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

:root {
  --bg: #0a0e17;
  --surface: #131a2b;
  --surface-hover: #1a2340;
  --border: #1e2a45;
  --text: #e2e8f0;
  --text-muted: #8892a8;
  --accent: #4a90d9;
  --accent-glow: rgba(74, 144, 217, 0.15);
  --green: #7cb342;
  --green-glow: rgba(124, 179, 66, 0.15);
  --blue: #4a90d9;
  --blue-glow: rgba(74, 144, 217, 0.15);
  --red: #e04040;
  --red-glow: rgba(224, 64, 64, 0.15);
  --radius: 12px;
  --transition: 0.2s ease;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

/* --- Hero --- */
.hero {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 3rem 1.5rem 2rem;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  top: -30%;
  left: 50%;
  transform: translateX(-50%);
  width: 400px;
  height: 400px;
  background:
    radial-gradient(circle at 30% 60%, var(--green-glow) 0%, transparent 50%),
    radial-gradient(circle at 50% 30%, var(--blue-glow) 0%, transparent 50%),
    radial-gradient(circle at 70% 60%, var(--red-glow) 0%, transparent 50%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

.hero-title {
  position: relative;
  z-index: 1;
  line-height: 1;
}

.hero-logo {
  width: min(80vw, 360px);
  height: auto;
  display: block;
  filter: drop-shadow(0 0 20px rgba(74, 144, 217, 0.2));
}

/* --- Container --- */
.container {
  width: 100%;
  max-width: 600px;
  margin: 0 auto;
  padding: 0 1rem 2rem;
}

/* --- Sections --- */
.section {
  --section-accent: var(--blue);
  --section-glow: var(--blue-glow);
  margin-bottom: 1.5rem;
}

/* Cycle: green → blue → red across sections */
.section:nth-of-type(3n+1) { --section-accent: var(--green); --section-glow: var(--green-glow); }
.section:nth-of-type(3n+2) { --section-accent: var(--blue);  --section-glow: var(--blue-glow);  }
.section:nth-of-type(3n)   { --section-accent: var(--red);   --section-glow: var(--red-glow);   }

.section-title {
  font-family: 'Orbitron', sans-serif;
  font-weight: 500;
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--section-accent);
  padding: 0 0.25rem 0.6rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.75rem;
}

/* --- Card Grid --- */
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.625rem;
}

.card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 1.25rem 0.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
  -webkit-tap-highlight-color: transparent;
  cursor: pointer;
}

.card:hover {
  background: var(--surface-hover);
  border-color: var(--section-accent);
  transform: translateY(-2px);
}

.card:active {
  transform: translateY(0);
}

.card-icon {
  width: 28px;
  height: 28px;
  color: var(--section-accent);
  flex-shrink: 0;
  transition: color var(--transition);
}

.card:hover .card-icon {
  color: #fff;
}

.card-label {
  font-weight: 500;
  font-size: 0.8rem;
  text-align: center;
  line-height: 1.3;
}

/* --- Footer --- */
.footer {
  text-align: center;
  padding: 1.5rem 1rem;
  font-size: 0.7rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================
   Responsive — Tablet & Desktop
   ============================================ */

/* Tablet (>= 480px) */
@media (min-width: 480px) {
  .hero-logo {
    width: min(70vw, 440px);
  }

  .grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 0.75rem;
  }

  .container {
    max-width: 680px;
  }
}

/* Desktop (>= 768px) */
@media (min-width: 768px) {
  .hero {
    padding: 4rem 2rem 2.5rem;
  }

  .hero-glow {
    width: 500px;
    height: 500px;
  }

  .hero-logo {
    width: min(60vw, 500px);
  }

  .container {
    max-width: 740px;
    padding: 0 2rem 3rem;
  }

  .grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 0.875rem;
  }

  .card {
    padding: 1.5rem 1rem;
    gap: 0.75rem;
  }

  .card-icon {
    width: 32px;
    height: 32px;
  }

  .card-label {
    font-size: 0.85rem;
  }

  .section-title {
    font-size: 0.75rem;
  }
}

/* Large desktop (>= 1024px) */
@media (min-width: 1024px) {
  .hero-logo {
    width: min(50vw, 560px);
  }

  .container {
    max-width: 860px;
  }

  .card:hover {
    box-shadow: 0 0 20px var(--section-glow), 0 4px 12px rgba(0, 0, 0, 0.3);
  }
}

/* --- Accessibility --- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none !important;
  }
}

/* Focus styles for keyboard navigation */
.card:focus-visible {
  outline: 2px solid var(--section-accent);
  outline-offset: 2px;
}