:root {
  --bg: #07111f;
  --surface: #101c2f;
  --surface-2: #16253c;
  --text: #f5f7fa;
  --muted: #9fb0c9;
  --primary: #5b7cff;
  --primary-2: #9b8cff;
  --accent: #2dd4bf;
  --border: rgba(255, 255, 255, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  line-height: 1.7;
  background: linear-gradient(135deg, var(--bg), #0f1c2d 60%, #111827);
  color: var(--text);
}

img {
  max-width: 100%;
}

code,
pre {
  font-family: "Cascadia Code", Consolas, monospace;
}

pre {
  background: #020817;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem;
  overflow-x: auto;
  color: #d8e4ff;
  margin: 0.8rem 0 0;
}

.hero {
  background: radial-gradient(circle at top left, rgba(91, 124, 255, 0.35), transparent 35%),
    linear-gradient(135deg, #0b1220, #111f36);
  padding: 4rem 1.25rem 3rem;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.3em;
  font-size: 0.8rem;
  color: var(--accent);
  margin-bottom: 0.6rem;
}

.hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin: 0 auto 1rem;
  max-width: 850px;
}

.lead {
  max-width: 760px;
  margin: 0 auto 1.5rem;
  color: var(--muted);
  font-size: 1.05rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  text-decoration: none;
  padding: 0.8rem 1.2rem;
  border-radius: 999px;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-2));
  color: white;
  box-shadow: 0 10px 25px rgba(91, 124, 255, 0.3);
}

.btn-secondary {
  color: var(--text);
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.04);
}

.top-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.7rem;
  padding: 1rem;
  position: sticky;
  top: 0;
  background: rgba(7, 17, 31, 0.92);
  backdrop-filter: blur(8px);
  z-index: 10;
  border-bottom: 1px solid var(--border);
}

.top-nav a {
  color: var(--text);
  text-decoration: none;
  border: 1px solid var(--border);
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  font-size: 0.95rem;
}

.top-nav a:hover {
  border-color: var(--accent);
  color: var(--accent);
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.15rem 3rem;
}

section {
  margin-bottom: 2rem;
}

.section-title {
  font-size: 1.6rem;
  margin-bottom: 1rem;
  border-bottom: 2px solid rgba(91, 124, 255, 0.3);
  padding-bottom: 0.4rem;
}

.intro-grid,
.cards-grid {
  display: grid;
  gap: 1rem;
}

.intro-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.cards-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.card {
  background: rgba(16, 28, 47, 0.95);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.2rem;
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.18);
}

.card h2,
.card h3 {
  margin-top: 0;
  color: #ffffff;
}

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

.card ul {
  padding-left: 1.1rem;
  margin: 0.7rem 0 0;
}

.card li {
  margin-bottom: 0.4rem;
}

.card code {
  color: #7dd3fc;
}

.large-card {
  grid-column: 1 / -1;
}

.tip-box {
  background: rgba(45, 212, 191, 0.14);
  border-left: 4px solid var(--accent);
  padding: 0.85rem 1rem;
  border-radius: 10px;
  margin: 1rem 0;
  color: #d5f9f4;
}

footer {
  text-align: center;
  padding: 2rem 1rem 3rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
}

@media (max-width: 900px) {
  .intro-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .hero {
    padding-top: 3rem;
  }

  .top-nav {
    justify-content: flex-start;
  }
}