:root {
  --primary: #0f2a44;
  --secondary: #2563eb;
  --light: #f5f7fa;
  --dark: #020617;
  --text: #334155;
  --muted: #64748b;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Inter', sans-serif;
  color: var(--text);
  line-height: 1.6;
}

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

.container {
  max-width: 1200px;
  margin: auto;
  padding: 0 20px;
}

/* Header */
.header {
  background: #fff;
  border-bottom: 1px solid #e5e7eb;
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.logo {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
}

.nav a {
  margin-left: 30px;
  font-weight: 500;
}

/* Buttons */
.btn-primary {
  background: var(--secondary);
  color: #fff;
  padding: 14px 28px;
  border-radius: 6px;
  font-weight: 600;
  display: inline-block;
}

.btn-outline {
  border: 1px solid var(--secondary);
  padding: 10px 20px;
  border-radius: 6px;
  color: var(--secondary);
}

/* Hero */
.hero {
  background: linear-gradient(120deg, #f8fafc, #eef2ff);
  padding: 90px 0;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero h1 {
  font-size: 44px;
  color: var(--primary);
  margin-bottom: 20px;
}

.hero p {
  font-size: 18px;
  color: var(--muted);
  margin-bottom: 30px;
}

.hero-box {
  background: #e5e7eb;
  height: 260px;
  border-radius: 12px;
}

/* Sections */
.section {
  padding: 80px 0;
}

.section.light {
  background: var(--light);
}

.section.dark {
  background: var(--primary);
  color: #fff;
}

.section-title {
  font-size: 32px;
  color: var(--primary);
  margin-bottom: 40px;
}

.section.dark h2 {
  color: #fff;
}

.center {
  text-align: center;
}

/* Cards */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
}

.card {
  background: #fff;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.06);
}

.section.dark .card {
  background: #0b1f36;
}

/* Footer */
.footer {
  background: var(--dark);
  color: #9ca3af;
  text-align: center;
  padding: 20px;
  font-size: 14px;
}

/* Responsive */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .nav {
    display: none;
  }

  .hero h1 {
    font-size: 34px;
  }
}