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

body {
  font-family: 'Segoe UI', sans-serif;
  background-color: #f5f5f5;
  color: #333;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Header ── */
header {
  background-color: #2c3e50;
  color: #fff;
  padding: 1.5rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

header h1 {
  font-size: 1.6rem;
  font-weight: 600;
}

nav a {
  color: #ecf0f1;
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 0.95rem;
  transition: color 0.2s;
}

nav a:hover {
  color: #3498db;
}

/* ── Main ── */
main {
  flex: 1;
  max-width: 860px;
  margin: 3rem auto;
  padding: 0 1.5rem;
}

/* ── Hero ── */
.hero {
  background-color: #fff;
  border-radius: 8px;
  padding: 2.5rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  text-align: center;
  margin-bottom: 2rem;
}

.hero h2 {
  font-size: 2rem;
  color: #2c3e50;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.05rem;
  color: #666;
  line-height: 1.7;
  max-width: 560px;
  margin: 0 auto 1.5rem;
}

/* ── Button ── */
.btn {
  display: inline-block;
  background-color: #3498db;
  color: #fff;
  padding: 0.7rem 1.8rem;
  border-radius: 5px;
  text-decoration: none;
  font-size: 0.95rem;
  transition: background-color 0.2s;
}

.btn:hover {
  background-color: #2980b9;
}

/* ── Cards ── */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.card {
  background-color: #fff;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.card h3 {
  font-size: 1.1rem;
  color: #2c3e50;
  margin-bottom: 0.6rem;
}

.card p {
  font-size: 0.9rem;
  color: #777;
  line-height: 1.6;
}

/* ── Footer ── */
footer {
  text-align: center;
  padding: 1.2rem;
  background-color: #2c3e50;
  color: #aaa;
  font-size: 0.85rem;
}