body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f4f6f8;
  color: #333;
  text-align: center;
}

header {
  padding: 40px 20px;
  background: linear-gradient(135deg, #2563eb, #1e40af);
  color: #fff;
}

.levels {
  display: flex;
  justify-content: center;
  gap: 20px;
  padding: 40px;
  flex-wrap: wrap;
}

.level {
  padding: 20px 30px;
  border-radius: 10px;
  text-decoration: none;
  color: white;
  font-size: 20px;
  font-weight: bold;
  transition: transform 0.2s;
}

.level:hover {
  transform: scale(1.05);
}

.basic { background: #22c55e; }
.intermediate { background: #f59e0b; }
.advanced { background: #ef4444; }

footer {
  padding: 20px;
  background: #111;
  color: #fff;
}