:root {
  --blue-dark: #023e7d;
  --blue: #0466c8;
  --blue-light: #61a5c2;
  --foam: #e9f5f9;
  --white: #ffffff;
  --text: #1b2a33;
  --text-muted: #4a5a63;
  --radius: 10px;
  --shadow: 0 4px 14px rgba(2, 62, 125, 0.12);
}

* {
  box-sizing: border-box;
}

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

header {
  background: linear-gradient(135deg, var(--blue-dark), var(--blue));
  color: var(--white);
  padding: 2rem 1.5rem;
  text-align: center;
}

header h1 {
  margin: 0 0 0.4rem;
  font-size: 2rem;
}

header p {
  margin: 0;
  color: #dbeeff;
}

nav {
  background: var(--blue-dark);
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  padding: 0.8rem;
  flex-wrap: wrap;
}

nav a {
  color: var(--white);
  text-decoration: none;
  font-weight: 600;
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius);
  transition: background 0.2s ease;
}

nav a:hover,
nav a:focus {
  background: var(--blue);
}

main {
  max-width: 900px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

.intro {
  text-align: center;
  margin-bottom: 2.5rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.4rem;
  border-top: 4px solid var(--blue-light);
}

.card h2,
.card h3 {
  color: var(--blue-dark);
  margin-top: 0;
}

.hub-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.hub-links a {
  display: block;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.8rem;
  text-decoration: none;
  color: var(--blue-dark);
  font-size: 1.2rem;
  font-weight: 700;
  text-align: center;
  border: 2px solid transparent;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.hub-links a:hover,
.hub-links a:focus {
  border-color: var(--blue);
  transform: translateY(-3px);
}

.hub-links span {
  display: block;
  margin-top: 0.4rem;
  font-size: 0.95rem;
  font-weight: 400;
  color: var(--text-muted);
}

footer {
  text-align: center;
  padding: 1.5rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}