/* 透明顶部导航栏 */
#top-header {
  position: fixed;
  top: -60px; /* 初始隐藏 */
  width: 100%;
  height: 60px;
  background: rgba(0, 0, 0, 0.05); /* 悬停时显示轻微透明度 */
  backdrop-filter: blur(5px); /* 毛玻璃效果 */
  transition: top 0.3s ease;
  z-index: 1000;
}

#top-header nav #top-header-ul {
  display: flex;
  justify-content: center;
  list-style: none;
  margin: 0;
  padding: 15px 0;
}

#top-header nav li {
  margin: 0 20px;
}

#top-header nav a {
  color: #333;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

#top-header nav a:hover {
  color: #ff66b2;
}

footer {
  position: fixed;
  display: flex;
  align-items: center;
  justify-content: center;
  left: 0;
  bottom: 0;
  width: 100%;
  z-index: 10;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
}
footer a {
  color: #999;
  text-decoration: none;
}