/* ============================================================================
   toolkit
   ============================================================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0a0a0a;
  --bg-secondary: #111111;
  --text-primary: #ffffff;
  --text-secondary: #a1a1aa;
  --text-muted: #52525b;
  --accent: #3b82f6;
  --accent-glow: rgba(59, 130, 246, 0.15);
  --border: rgba(255, 255, 255, 0.08);
}

body {
  background: var(--bg-primary) url(../img/og-medusa.jpg) center center / cover no-repeat fixed;
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, 'Inter', -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
  position: relative;
  overflow-x: hidden;
}

/* Dark overlay for readability */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(0, 0, 0, 0.75) 0%, rgba(0, 0, 0, 0.65) 50%, rgba(0, 0, 0, 0.75) 100%);
  pointer-events: none;
  z-index: 0;
}

.container {
  max-width: 640px;
  width: 100%;
  text-align: center;
  position: relative;
  z-index: 1;
}

h1 {
  font-size: 64px;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
  background: linear-gradient(180deg, #fff 0%, #a1a1aa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.tagline {
  font-size: 20px;
  color: var(--text-secondary);
  margin-bottom: 56px;
  font-weight: 400;
  white-space: nowrap;
  overflow-x: auto;
}

/* Primary CTA */
.nav-links {
  margin-bottom: 40px;
}

.button-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 32px;
  background: var(--text-primary);
  color: var(--bg-primary);
  font-size: 15px;
  font-weight: 600;
  border-radius: 8px;
  text-decoration: none;
  transition: all 0.2s ease;
  box-shadow: 0 0 40px rgba(255, 255, 255, 0.1);
}

.button-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 60px rgba(255, 255, 255, 0.15);
}

/* Secondary nav */
.nav-secondary {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 32px;
}

.nav-secondary a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 10px 16px;
  border-radius: 6px;
  transition: all 0.15s ease;
}

.nav-secondary a:hover {
  color: var(--text-primary);
  background: var(--border);
}

/* Tertiary nav */
.nav-tertiary {
  display: flex;
  justify-content: center;
  gap: 8px;
}

.nav-tertiary a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 13px;
  padding: 8px 12px;
  border-radius: 6px;
  transition: all 0.15s ease;
}

.nav-tertiary a:hover {
  color: var(--text-secondary);
}

footer {
  margin-top: 80px;
  font-size: 13px;
  color: var(--text-muted);
}

/* ============================================================================
   Inner Pages
   ============================================================================ */

.card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 48px;
  margin: 32px 0;
  text-align: left;
}

.card-title {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 32px;
  text-align: center;
}

.card-bullets {
  list-style: none;
}

.card-bullets li {
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
  color: var(--text-secondary);
}

.card-bullets li:last-child {
  border-bottom: none;
}

.back-link {
  display: inline-block;
  margin-top: 32px;
  color: var(--text-muted);
  font-size: 14px;
  text-decoration: none;
  transition: color 0.15s;
}

.back-link:hover {
  color: var(--text-secondary);
}

/* Diagram */
.diagram-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 48px;
  margin: 40px 0;
}

.diagram {
  display: flex;
  flex-direction: column;
  gap: 20px;
  align-items: center;
}

.diagram-row {
  display: flex;
  gap: 16px;
  align-items: center;
  justify-content: center;
}

.box {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  padding: 16px 28px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  min-width: 110px;
  text-align: center;
  color: var(--text-primary);
  letter-spacing: 0.02em;
}

.arrow {
  color: var(--text-muted);
  font-size: 20px;
}

.label {
  font-size: 12px;
  color: var(--text-muted);
  min-width: 110px;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.spacer {
  min-width: 70px;
}

.bullets {
  margin: 40px 0;
}

.bullets p {
  font-size: 16px;
  color: var(--text-secondary);
  margin: 12px 0;
  font-weight: 400;
}

/* ============================================================================
   Mobile
   ============================================================================ */

@media (max-width: 600px) {
  h1 {
    font-size: 42px;
  }

  .tagline {
    font-size: 15px;
    margin-bottom: 40px;
    white-space: nowrap;
  }

  .nav-secondary {
    flex-wrap: wrap;
  }

  .card {
    padding: 28px;
  }

  .diagram-row {
    flex-wrap: wrap;
  }

  .box {
    min-width: 90px;
    padding: 12px 20px;
  }
}