body {
  font-family: 'Arial', sans-serif;
  margin: 0;
  padding: 0;
  background-color: #000;
  color: #f8f8f8;
}

header.hero {
  padding: 60px 20px;
  text-align: center;
  background-size: cover;
  background-position: center;
  color: white;
}

section img {
  max-width: 100%;
  height: 400px;
  display: block;
  margin: 0 auto;
  image-rendering: auto;           /* 默认 */
  image-rendering: crisp-edges;    /* 尝试更清晰 */
  image-rendering: -webkit-optimize-contrast;
}

section
 {
    background: #222;
  color: white;
    margin: 20px auto;
    padding: 40px;
    max-width: 1100px;
    border-radius: 10px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 1);
    transition: transform 0.3s ease-in-out;
}

nav {
  background: #333;
  padding: 10px;
  text-align: center;
}

nav a {
  color: white;
  margin: 0 15px;
  text-decoration: none;
}

main {
  padding: 20px;
}

footer {
  text-align: center;
  background: #222;
  color: white;
  padding: 10px;
  margin-top: 20px;
}

.logo-placeholder {
  font-weight: bold;
  font-size: 20px;
}

.image-placeholder {
  width: 100%;
  height: 180px;
  background-color: #ccc;
  text-align: center;
  line-height: 180px;
  margin-top: 10px;
}