body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #0d1117;
  color: #e6edf3;
}

header {
  background: #161b22;
  padding: 20px;
  text-align: center;
  border-bottom: 1px solid #30363d;
}

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

nav a {
  color: #58a6ff;
  margin: 0 15px;
  text-decoration: none;
  font-size: 1.1rem;
}

nav a:hover {
  text-decoration: underline;
}

.hero {
  text-align: center;
  padding: 100px 20px;
}

.hero h2 {
  font-size: 2.5rem;
  margin-bottom: 10px;
}

.hero p {
  font-size: 1.2rem;
  opacity: 0.85;
  max-width: 600px;
  margin: 0 auto 20px;
}

button {
  background: #238636;
  color: white;
  border: none;
  padding: 12px 25px;
  font-size: 1rem;
  border-radius: 6px;
  cursor: pointer;
}

button:hover {
  background: #2ea043;
}

footer {
  text-align: center;
  padding: 20px;
  margin-top: 80px;
  opacity: 0.6;
}