:root {
  --ink: #172033;
  --muted: #5d6679;
  --line: #d8dee9;
  --panel: #ffffff;
  --surface: #f4f8fb;
  --navy: #19324d;
  --azure: #0078d4;
  --teal: #008575;
  --gold: #d29922;
  --shadow: 0 18px 48px rgba(25, 50, 77, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.6;
  background: var(--surface);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.95);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}

.navbar {
  width: min(1120px, calc(100% - 32px));
  min-height: 72px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  color: var(--azure);
  font-size: 1.2rem;
  font-weight: 800;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-links a {
  min-width: 88px;
  padding: 10px 16px;
  color: var(--muted);
  font-weight: 700;
  text-align: center;
  border-radius: 6px;
}

.nav-links a:hover,
.nav-links a.active {
  color: #ffffff;
  background: var(--azure);
}

.hero {
  min-height: calc(100vh - 72px);
  display: flex;
  align-items: center;
  background:
    linear-gradient(115deg, rgba(14, 34, 55, 0.92), rgba(0, 120, 212, 0.68)),
    url("https://images.unsplash.com/photo-1451187580459-43490279c0fa?auto=format&fit=crop&w=1800&q=80") center/cover;
}

.hero-content,
.page-title,
.section {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.hero-content {
  padding: 88px 0;
  color: #ffffff;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #a9f3e7;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 850px;
  margin-bottom: 24px;
  font-size: clamp(2.3rem, 6vw, 5rem);
  line-height: 1.04;
}

h2 {
  margin-bottom: 16px;
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  line-height: 1.18;
}

h3 {
  margin-bottom: 10px;
  font-size: 1.1rem;
}

.lead {
  max-width: 760px;
  color: inherit;
  font-size: 1.15rem;
}

.hero .lead {
  color: #e6f2fb;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 18px;
  border-radius: 6px;
  font-weight: 800;
}

.button.primary {
  color: #ffffff;
  background: var(--azure);
}

.button.secondary {
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.72);
}

.section {
  padding: 72px 0;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 28px;
}

.feature-grid,
.code-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.feature-card,
.code-card,
.step,
.note-section {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.feature-card {
  padding: 28px;
}

.feature-card p,
.step p,
.note-section p,
.timeline-item p {
  margin-bottom: 0;
  color: var(--muted);
}

.timeline-section {
  border-top: 1px solid var(--line);
}

.timeline {
  display: grid;
  gap: 16px;
}

.timeline-item {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 18px;
  align-items: start;
  padding: 22px 0;
  border-top: 1px solid var(--line);
}

.year {
  color: var(--gold);
  font-weight: 900;
}

.page-title {
  padding: 72px 0 36px;
}

.page-title .lead {
  color: var(--muted);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.step {
  padding: 24px;
}

.step-number {
  display: block;
  margin-bottom: 18px;
  color: var(--azure);
  font-size: 0.9rem;
  font-weight: 900;
}

.split-section {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: 42px;
  align-items: start;
  border-top: 1px solid var(--line);
}

.check-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  padding: 16px 0 16px 32px;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
  position: relative;
}

.check-list li::before {
  content: "";
  width: 10px;
  height: 10px;
  position: absolute;
  top: 23px;
  left: 4px;
  border-radius: 50%;
  background: var(--teal);
}

.code-card {
  overflow: hidden;
}

.code-card h2 {
  margin: 0;
  padding: 22px 24px;
  font-size: 1.1rem;
  border-bottom: 1px solid var(--line);
}

pre {
  margin: 0;
  padding: 24px;
  overflow-x: auto;
  color: #eaf2fb;
  background: var(--navy);
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.9rem;
}

.note-section {
  padding: 28px;
}

.site-footer {
  padding: 28px 16px;
  color: #ffffff;
  text-align: center;
  background: var(--navy);
}

.site-footer p {
  margin: 0;
}

@media (max-width: 820px) {
  .navbar {
    align-items: flex-start;
    flex-direction: column;
    padding: 18px 0;
  }

  .nav-links {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
  }

  .nav-links a {
    min-width: 0;
    padding: 10px 8px;
  }

  .hero {
    min-height: auto;
  }

  .feature-grid,
  .code-grid,
  .steps,
  .split-section {
    grid-template-columns: 1fr;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}