body {
  margin: 0;
  font-family: Arial;
  background: #f5f5f5;
}

header {
  background: linear-gradient(45deg,#007bff,#00c6ff);
  color: white;
  padding: 15px;
  text-align: center;
  font-size: 20px;
}

footer {
  background: #ccc;
  padding: 10px;
  text-align: center;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit,minmax(150px,1fr));
  gap: 15px;
  padding: 15px;
}

.card {
  background: white;
  border-radius: 12px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.2);
  overflow: hidden;
  text-align: center;
}

.card img {
  width: 100%;
}

.card h3 {
  padding: 10px;
  font-size: 16px;
}

.heading {
  background: #007bff;
  color: white;
  padding: 10px;
}

.ad {
  background: #eaeaea;
  padding: 20px;
  margin: 15px;
  text-align: center;
  border-radius: 10px;
}

button {
  display: block;
  margin: 20px auto;
  padding: 12px 20px;
  background: #28a745;
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 16px;
}