:root {
  --primary: #0f172a;
  --secondary: #1e40af;
  --light: #f8fafc;
  --text: #1e293b;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: Arial, Helvetica, sans-serif;
}

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

/* =====================
   Layout
===================== */
.container {
  max-width: 1100px;
  margin: auto;
  padding: 0 20px;
}

/* =====================
   Header
===================== */
.site-header {
  background: var(--primary);
  color: white;
  padding: 50px 0;
  text-align: center;
}

.header-flex {
  display: flex;
  align-items: center;
  gap: 20px;
  justify-content: center;
}

.logo {
  height: 60px;
}

/* Responsive Header */
@media (max-width: 600px) {
  .header-flex {
    flex-direction: column;
    text-align: center;
  }
}

/* =====================
   Navigation
===================== */
.navbar {
  background: #ffffff;
  border-bottom: 2px solid var(--secondary);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar ul {
  display: flex;
  justify-content: center;
  list-style: none;
  gap: 30px;
  padding: 15px 0;
}

a {
  color: var(--secondary);
  text-decoration: none;
  font-weight: 500;
}

.navbar a {
  padding-bottom: 6px;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease;
}

.navbar a:hover {
  border-bottom-color: var(--secondary);
}

/* =====================
   Sections
===================== */
.section {
  padding: 70px 0;
}

.section-alt {
  background: #f1f5f9;
}

/* =====================
   Components
===================== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

.card {
  background: white;
  padding: 30px;
  border-radius: 12px;
  border: 1px solid #e5e7eb;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
}

/* =====================
   Footer
===================== */
.site-footer {
  background: #020617;
  color: #e0e7ff;
  text-align: center;
  padding: 40px 0;
  margin-top: 60px;
}