:root {
  --bg: #0f172a;
  --bg-alt: #111b31;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent-arcade: #f97316;
  --accent-school: #0ea5e9;
  --accent-lab: #22c55e;
  --accent-blog: #a855f7;
  --card-radius: 1rem;
  --max-width: min(1100px, 92vw);
  --shadow: 0 25px 45px rgba(15, 23, 42, 0.35);
  --transition: 250ms ease;
}

* {
  box-sizing: border-box;
}

html,
body {
  padding: 0;
  margin: 0;
  background: linear-gradient(135deg, #0f172a 0%, #0b1120 60%, #020617 100%);
  color: var(--text);
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont,
    sans-serif;
  min-height: 100%;
}

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

a:focus-visible {
  outline: 3px solid currentColor;
  outline-offset: 4px;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(2rem, 6vw, 4rem) 0;
}

main {
  width: 100%;
  max-width: var(--max-width);
  display: grid;
  gap: clamp(2rem, 5vw, 3rem);
}

header {
  display: grid;
  gap: 1rem;
  text-align: center;
}

.title {
  font-size: clamp(2.8rem, 6vw, 3.6rem);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-weight: 700;
  margin: 0;
}

.subtitle {
  margin: 0 auto;
  max-width: 60ch;
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  color: var(--muted);
  line-height: 1.6;
}

.nav-grid {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: clamp(1.5rem, 4vw, 2.5rem);
  width: 100%;
}

.section-card {
  position: relative;
  overflow: hidden;
  padding: clamp(1.8rem, 3vw, 2.5rem);
  border-radius: var(--card-radius);
  background: var(--bg-alt);
  box-shadow: var(--shadow);
  border: 1px solid rgba(148, 163, 184, 0.1);
  display: grid;
  gap: 1.25rem;
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition);
  width: min(420px, 100%);
}

.section-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 30%, rgba(148, 163, 184, 0.15));
  opacity: 0;
  transition: opacity var(--transition);
}

.section-card:hover,
.section-card:focus-visible {
  transform: translateY(-6px);
  box-shadow: 0 35px 60px rgba(15, 23, 42, 0.45);
  border-color: rgba(148, 163, 184, 0.25);
}

.section-card:hover::after,
.section-card:focus-visible::after {
  opacity: 1;
}

.section-card h2 {
  font-size: clamp(1.6rem, 2.6vw, 2rem);
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.section-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.section-card span.section-tag {
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(226, 232, 240, 0.6);
}

.section-card .cta {
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: inherit;
}

.section-card .cta svg {
  width: 1em;
  height: 1em;
  transition: transform var(--transition);
}

.section-card:hover .cta svg,
.section-card:focus-visible .cta svg {
  transform: translateX(4px);
}

.section-card.arcade {
  border-top: 4px solid var(--accent-arcade);
}

.section-card.school {
  border-top: 4px solid var(--accent-school);
}

.section-card.lab {
  border-top: 4px solid var(--accent-lab);
}

.section-card.blog {
  border-top: 4px solid var(--accent-blog);
}

footer {
  text-align: center;
  color: rgba(226, 232, 240, 0.5);
  font-size: 0.9rem;
  margin-top: 1rem;
}

footer a {
  color: rgba(129, 140, 248, 0.8);
}

@media (max-width: 600px) {
  header {
    text-align: left;
  }

  .subtitle {
    text-align: left;
  }
}