body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  line-height: 1.6;
}
header {
  background: #ffffff;
  color: black;
  padding: 1rem 2rem;
  text-align: center;
}
header img {
  max-width: 120px;
  margin-bottom: 0.5rem;
}
nav {
  background: #005599;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
}
nav a, .lang-toggle {
  color: white;
  margin: 0.25rem;
  text-decoration: none;
  padding: 0.5rem 1rem;
  background-color: #3399ff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: bold;
  text-align: center;
}
section {
  padding: 2rem;
}
.hero {
  background: url('huayou_images/pdf_page_1.jpg') no-repeat center center/cover;
  color: white;
  text-shadow: 1px 1px 2px #000;
  padding: 6rem 2rem;
  text-align: center;
}
@media (max-width: 600px) {
  .hero {
    padding: 3rem 1rem;
  }
  .card {
    flex: 1 1 100%;
  }
}
.cards {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}
.card {
  flex: 1 1 300px;
  background: #eee;
  padding: 1rem;
  border-radius: 8px;
}
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1rem;
}
.gallery img {
  width: 100%;
  border-radius: 8px;
}
footer {
  background: #003366;
  color: white;
  text-align: center;
  padding: 1rem;
}