/* === Fonts === */
  /* 设置网页背景 */
  body {
    background-image: 
      linear-gradient(rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.80)), /* 貌似是渐变？ */
      url("images/background.jpg"); /* 背景图片 */
    height: 100vh; /* 使 body 占满整个视口高度 */
    display: flex;
    justify-content: center; /* 水平居中 */
    align-items: center; /* 垂直居中 */
    background-size: cover; /* 背景图覆盖整个区域 */
    background-position: center; /* 背景图居中 */
    background-repeat: no-repeat; /* 防止重复 */
    background-attachment: fixed; /* 背景固定，不随页面滚动 */
  }






/* === Title Styling === */
.title {
  background-size: cover; 
  background-position: center;
  color: rgb(36, 36, 36); 
  padding: 0px;
  border-radius: 10px;
  text-align: center;
  font-size: 2.6em;
}

/* === Subtitle animation === */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.subtitle {
  font-size: 30px;
  font-weight: 400;
  color: #000000;
  opacity: 0;
  animation: fadeIn 1s ease-in-out forwards;
  text-align: center;
}








/* 悬停显示下拉菜单 */
.navbar .nav-item.dropdown:hover .dropdown-menu {
  display: block;       /* 悬停时显示下拉菜单 */
  margin-top: 0;        /* 去除偏移，确保紧贴导航栏 */
  transition: 0.3s;     /* 添加动画效果 */
}

/* 美化下拉菜单 */
.navbar .dropdown-menu {
  background-color: #f8f9fa;    /* 背景色 */
  border-radius: 5px;           /* 圆角边框 */
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1); /* 阴影效果 */
  min-width: 150px;                  /* 最小宽度，避免过小 */
  padding: 8px 0;                    /* 上下内边距 */
  transition: box-shadow 0.3s;       /* 阴影过渡效果 */
}

/* 悬停时菜单项变色 */
.navbar .dropdown-menu a:hover {
  background-color: #d0d0d0;    /* 悬停背景色 */
  color: #fff;                  /* 悬停字体颜色 */
}

.navbar .nav-item.dropdown {
  position: relative;
}

.navbar .nav-item.dropdown:hover .dropdown-menu {
  display: block;
  opacity: 0;           /* 初始透明 */
  animation: fadeIn 0.3s forwards;  /* 添加淡入动画 */
}

/* 动画效果 */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);  /* 从下往上淡入 */
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}







/* === Author Cards === */
.authors-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
  margin-top: 2rem;
}

.author-card {
  background-color: rgba(255, 255, 255, 0.85);
  border-radius: 12px;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  padding: 1.2rem 1.5rem;
  text-align: center;
  width: 220px;
  font-size: 0.95rem;
  line-height: 1.4;
  transition: transform 0.3s ease;
}

.author-card:hover {
  transform: translateY(-5px);
}

.author-card a {
  display: inline-block;
  margin-top: 0.5rem;
  text-decoration: none;
  color: #007acc;
  font-weight: 500;
}

.author-card img {
  margin-top: 0.5rem;
  filter: drop-shadow(0 1px 2px rgba(0,0,0,0.2));
  transition: transform 0.3s ease;
}

.author-card img:hover {
  transform: scale(1.05);
}

/* === Fix image under navbar === */
img.about-image {
  display: block;
  margin-top: auto;
  margin-left: auto;
  margin-right: auto;
}