body {
  font-family: 'Inter', sans-serif;
  margin: 0;
  background: #f8f9fa;
  color: #2d2d2d;
}
nav {
  background-color: #1e1e1e;
  padding: 1rem;
  text-align: center;
}
nav a {
  color: #fff;
  text-decoration: none;
  margin: 0 1rem;
}
nav a.active {
  color: #00b894;
}
header {
  text-align: center;
  padding: 2rem;
  background: #00b894;
  color: white;
}
.main-section {
  max-width: 900px;
  margin: auto;
  padding: 2rem;
}
.card {
  background: white;
  padding: 1.5rem;
  margin: 1rem 0;
  border-radius: 0.5rem;
  box-shadow: 0 0 10px rgba(0,0,0,0.05);
}
.btn {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.5rem 1rem;
  background: #00b894;
  color: white;
  text-decoration: none;
  border-radius: 0.25rem;
}
footer {
  background: #1e1e1e;
  color: #aaa;
  text-align: center;
  padding: 1rem;
}