:root {
  --bg-dark: #0b1220;
  --bg-light: #f5f7fb;
  --primary: #1e3a8a;
  --secondary: #334155;
  --accent: #0ea5e9;
  --text-light: #e5e7eb;
  --text-dark: #0f172a;
  --card-bg: #ffffff;
  --border: #e2e8f0;
}

/* Reset */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
}

body {
  background: var(--bg-light);
  color: var(--text-dark);
  line-height: 1.7;
}

/* Header / Nav */
header {
  background: var(--bg-dark);
  color: var(--text-light);
  padding: 18px 48px;
  border-bottom: 3px solid var(--primary);
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

nav strong {
  font-size: 20px;
  letter-spacing: 0.5px;
}

nav a {
  color: var(--text-light);
  margin-left: 22px;
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
}

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

/* Hero */
.hero {
  background: linear-gradient(135deg, #020617, #1e293b);
  color: white;
  padding: 90px 48px;
}

.hero h1 {
  font-size: 38px;
  margin-bottom: 10px;
}

.hero p {
  font-size: 16px;
  opacity: 0.9;
}

/* Sections */
section {
  padding: 70px 48px;
  max-width: 1150px;
  margin: auto;
}

section h1 {
  font-size: 32px;
  margin-bottom: 20px;
  color: var(--primary);
}

section h2 {
  font-size: 22px;
  margin-bottom: 16px;
  color: var(--primary);
}

section p {
  max-width: 900px;
  margin-bottom: 20px;
  color: #1f2937;
}

/* Card layout (used by sub-pages automatically) */
ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  list-style: none;
  margin-top: 30px;
}

ul li {
  background: var(--card-bg);
  padding: 22px 24px;
  border-left: 4px solid var(--primary);
  border-radius: 6px;
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.05);
  font-size: 15px;
}

/* Strategic emphasis */
strong {
  color: #b91c1c;
}

/* Footer */
footer {
  background: var(--secondary);
  color: var(--text-light);
  padding: 32px 48px;
  margin-top: 80px;
  font-size: 13px;
  letter-spacing: 0.3px;
}