body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 20px;
  text-align: center;
  background: #f4f4f4;
  color: #333;
}
img, video {
  border-radius: 12px;
  max-width: 100%;
  height: auto;
}
.btn {
  padding: 10px 20px;
  background: #007bff;
  color: #fff;
  text-decoration: none;
  border-radius: 5px;
}
.btn:hover {
  background: #0056b3;
}
ul {
  list-style: none;
  padding: 0;
}
ul li {
  margin: 10px 0;
}
@media (max-width: 600px) {
  img, video { width: 100%; }
}