/* 页面顶部留白 */
body {
    padding-top: 56px;
}
  
/* 左对齐 */
.left-aligned {
    margin-left: auto;
}
  
/* 导航栏背景色 */
.bg-dark {
    background-color: #6a7988 !important;
}
  
/* 顶部大图背景色（Hero 区块） */
.bg-hero {
    background-color: #743751;
}
  
/*  Bootstrap Callout 样式 */
.bd-callout {
    padding: 1.25rem;
    margin-top: 1.25rem;
    margin-bottom: 1.25rem;
    border: 1px solid #a6a6a6;
    border-left-width: .25rem;
    border-radius: .25rem;
}
.bd-callout h4 {
    margin-bottom: 1.25rem;
}
.bd-callout p:last-child {
    margin-bottom: 0;
}
.bd-callout code {
    border-radius: .25rem;
}
.bd-callout + .bd-callout {
    margin-top: -0.25rem;
}
.bd-callout-info {
    border-left-color: #5bc0de;
}
.bd-callout-warning {
    border-left-color: #f0ad4e;
}
.bd-callout-danger {
    border-left-color: #d9534f;
}
  
/* Footer 样式 */
footer a {
    color: white;
    font-weight: bold;
    text-decoration: none;
}
footer a:hover {
    color: white;
    text-decoration: underline;
}
  
/* Logo 鼠标悬停放大 */
.navbar-brand img,
.navbar-nav img,
.navbar .nav-link img {
    transition: transform 0.3s ease;
}
.navbar-brand img:hover,
.navbar-nav img:hover,
.navbar .nav-link img:hover {
    transform: scale(1.2);
}
  
/* 鼠标悬停自动展开下拉菜单 */
.navbar .dropdown:hover > .dropdown-menu {
    display: block !important;
    margin-top: 0;
    opacity: 1;
    pointer-events: auto;
    transition: opacity 0.2s ease-in-out;
}
  
/* 初始状态隐藏并禁用点击 */
.dropdown-menu {
    display: none;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease-in-out;
    border-radius: 0.5rem;
    box-shadow: 0 0.5rem 1rem rgba(0,0,0,0.1);
}
  
/* 下拉项 hover 高亮 */
.dropdown-item:hover {
    background-color: #dee2e6;
    color: #000;
}

/* 柔和下拉 */
.navbar .dropdown-menu {
    border-radius: 0.5rem;
    box-shadow: 0 0.5rem 1rem rgba(0,0,0,0.1);
}

/* 箭头反转 */
.navbar .dropdown-toggle::after {
    transition: transform 0.3s ease;
}
.navbar .dropdown:hover .dropdown-toggle::after {
    transform: rotate(180deg);
}