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

body {
  font-family: 'Segoe UI', sans-serif;
  background: #f2f4f8;
  color: #1e1e1e;
  line-height: 1.6;
}

header {
  background: #121212;
  color: #fff;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1rem;
}

nav ul li a {
  color: #fff;
  text-decoration: none;
}

.hero {
  padding: 4rem 2rem;
  text-align: center;
  background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  color: white;
}

.module {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 0 15px rgba(0,0,0,0.05);
  margin-bottom: 2rem;
}

.modules {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  padding: 2rem;
}

button, .btn {
  padding: 0.6rem 1.2rem;
  border: none;
  background: #007bff;
  color: white;
  border-radius: 8px;
  cursor: pointer;
  text-decoration: none;
}

footer {
  text-align: center;
  padding: 1rem;
  background: #121212;
  color: #aaa;
  margin-top: 2rem;
}