:root {
  --bg: #f7f8fc;
  --surface: #ffffff;
  --text: #1f2a44;
  --muted: #667089;
  --primary: #3a86ff;
  --primary-dark: #245ec9;
  --border: #dfe5f0;
  --shadow: 0 10px 30px rgba(31, 42, 68, 0.08);
  --radius: 18px;
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

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

img {
  max-width: 100%;
  display: block;
}

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

.container {
  width: min(var(--container), calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  gap: 20px;
}

.logo {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.main-nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.main-nav a {
  font-weight: 600;
  color: var(--muted);
}

.main-nav a.active,
.main-nav a:hover {
  color: var(--primary);
}

.hero {
  padding: 60px 0 30px;
  text-align: center;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(2rem, 4vw, 3rem);
}

.hero p {
  max-width: 760px;
  margin: 0 auto;
  color: var(--muted);
}

.setup-section {
  padding: 20px 0 60px;
}

.setup-grid {
  display: grid;
  gap: 28px;
}

.setup-card {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.setup-card img {
  width: 100%;
  height: 100%;
  min-height: 320px;
  object-fit: cover;
}

.setup-content {
  padding: 28px;
}

.setup-content h2 {
  margin-top: 0;
  margin-bottom: 12px;
}

.setup-content p {
  color: var(--muted);
  margin-bottom: 14px;
}

.setup-content ul {
  margin: 0 0 20px;
  padding-left: 20px;
  color: var(--text);
}

.btn {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
  padding: 12px 20px;
  border-radius: 999px;
  transition: background 0.2s ease;
}

.btn:hover {
  background: var(--primary-dark);
}

.site-footer {
  padding: 24px 0 36px;
  text-align: center;
  color: var(--muted);
}

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

  .setup-card img {
    min-height: 240px;
  }
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero {
    padding-top: 40px;
  }

  .setup-content {
    padding: 22px;
  }
}