:root {
  color-scheme: dark;
  --bg: #07111f;
  --bg-alt: #0d1b2d;
  --surface: rgba(255, 255, 255, 0.08);
  --text: #f5f7fb;
  --muted: #aab6ca;
  --accent: #6ee7f9;
  --accent-strong: #2dd4bf;
  --border: rgba(255, 255, 255, 0.14);
  --shadow: 0 20px 50px rgba(0, 0, 0, 0.25);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, "Segoe UI", Roboto, Arial, sans-serif;
  background: linear-gradient(135deg, var(--bg), #10223d 55%, #0f223a);
  color: var(--text);
  line-height: 1.6;
}

img {
  max-width: 100%;
}

.container {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
}

.hero {
  min-height: 100vh;
  background: radial-gradient(circle at top left, rgba(110, 231, 249, 0.22), transparent 30%),
    radial-gradient(circle at right, rgba(45, 212, 191, 0.16), transparent 24%);
  padding-bottom: 4rem;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 0;
}

.brand {
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--text);
}

.nav-links {
  display: flex;
  gap: 1.4rem;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  transition: color 180ms ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--text);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 0.28rem;
  background: transparent;
  border: 0;
  padding: 0.3rem;
  cursor: pointer;
}

.menu-toggle span {
  width: 1.4rem;
  height: 2px;
  background: var(--text);
  display: block;
}

.hero-content {
  padding: 5rem 0 2rem;
  max-width: 780px;
}

.eyebrow,
.section-label {
  text-transform: uppercase;
  letter-spacing: 0.24em;
  font-size: 0.8rem;
  color: var(--accent);
  margin-bottom: 1rem;
}

h1,
h2,
h3 {
  line-height: 1.1;
  margin-top: 0;
}

h1 {
  font-size: clamp(2.5rem, 4vw, 4.3rem);
  margin-bottom: 1rem;
}

h2 {
  font-size: clamp(1.9rem, 2.5vw, 2.6rem);
  margin-bottom: 1rem;
}

.hero-copy {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 1.8rem;
  max-width: 680px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.8rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.25rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #032338;
  box-shadow: var(--shadow);
}

.button.secondary {
  border: 1px solid var(--border);
  color: var(--text);
  background: rgba(255, 255, 255, 0.03);
}

.hero-highlights {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  padding: 0;
  margin: 0;
  list-style: none;
  color: var(--muted);
}

.hero-highlights li {
  padding: 0.55rem 0.8rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
  border-radius: 999px;
}

.section {
  padding: 5rem 0;
}

.alt {
  background: rgba(255, 255, 255, 0.03);
}

.split {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 2rem;
  align-items: start;
}

.split p {
  color: var(--muted);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.2rem;
  margin-top: 2rem;
}

.card,
.speaker,
.cta-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1.25rem;
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.card h3,
.speaker h3 {
  margin-bottom: 0.6rem;
}

.card p,
.speaker p {
  color: var(--muted);
}

.speaker-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.2rem;
  margin-top: 2rem;
}

.cta-section {
  padding-top: 2rem;
}

.cta-box {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
}

.footer {
  padding: 1.2rem 0 2rem;
  color: var(--muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  border-top: 1px solid var(--border);
  padding-top: 1rem;
}

@media (max-width: 820px) {
  .card-grid,
  .speaker-list,
  .split {
    grid-template-columns: 1fr;
  }

  .cta-box,
  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 640px) {
  .nav {
    align-items: flex-start;
    flex-wrap: wrap;
  }

  .menu-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 0.7rem;
    padding-top: 0.8rem;
  }

  .nav-links.open {
    display: flex;
  }

  .hero-content {
    padding-top: 3rem;
  }
}