.navbar-custom {
    background-color: #416fbb;
    border: none;
    margin-bottom: 0;
    min-height: 50px;
}

.navbar-custom .navbar-brand {
    color: #ffffff;
    font-size: 24px;
    font-weight: bold;
    height: 60px;
    line-height: 30px;
}

.navbar-custom .navbar-nav>li>a {
    color: #ffffff;
    font-size: 20px;
    padding: 20px 25px;
    transition: background-color 0.3s ease;
}

.navbar-custom .navbar-nav>li>a:hover,
.navbar-custom .navbar-nav>li>a:focus {
    background-color: #0c2461;
}

/* 下拉菜单基础样式 */
.dropdown-menu {
    background-color: #416fbb;
    border: none;
    border-radius: 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    min-width: 200px;
    padding: 0;
    display: block;
    opacity: 0;
    visibility: hidden;
    position: absolute;
    transform: translateY(-10px);
    transition: all 0.3s ease;
}

/* 桌面端悬停显示下拉菜单 */
@media (min-width: 768px) {
    .dropdown:hover .dropdown-menu {
        opacity: 1;
        visibility: visible;
        transform: translateY(0);
    }
}

.dropdown-menu>li>a {
    color: #ffffff;
    padding: 12px 20px;
    font-size: 18px;
    transition: all 0.3s ease;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.dropdown-menu>li:last-child>a {
    border-bottom: none;
}

.dropdown-menu>li>a:hover {
    background-color: #0c2461;
    color: #ffffff;
    padding-left: 25px;
}

.navbar-toggle {
    font-size: 14px;
}

.navbar-custom .navbar-toggle {
    border-color: #ffffff;
}

.navbar-custom .navbar-toggle .icon-bar {
    background-color: #ffffff;
}

/* 移动端样式 */
@media (max-width: 767px) {

    /* 导航菜单容器绝对定位 */
    .navbar-collapse {
        position: absolute;
        top: 60px;
        /* 导航栏高度 */
        left: 0;
        right: 0;
        background-color: #416fbb;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
        padding: 0;
        margin: 0;
        max-height: calc(100vh - 60px);
        /* 最大高度为视口高度减去导航栏高度 */
        overflow-y: auto;
        z-index: 1000;
        opacity: 0;
        visibility: hidden;
        transform: translateY(-10px);
        transition: all 0.3s ease;
    }

    /* 展开时显示导航菜单 */
    .navbar-collapse.in {
        opacity: 1;
        visibility: visible;
        transform: translateY(0);
    }

    /* 下拉菜单样式 */
    .dropdown-menu {
        position: static;
        float: none;
        width: 100%;
        background-color: #162b6f;
        opacity: 1;
        visibility: visible;
        transform: none;
        display: none;
    }

    .dropdown.open .dropdown-menu {
        display: block;
    }

    .navbar-custom .navbar-nav {
        margin: 0;
    }

    .navbar-custom .navbar-nav>li>a {
        padding: 15px;
    }

    .navbar-custom .navbar-nav .open .dropdown-menu>li>a {
        color: #ffffff;
        padding: 10px 15px 10px 25px;
    }

    .navbar-custom .navbar-nav .open .dropdown-menu>li>a:hover {
        background-color: #0c2461;
    }
}

/* 箭头动画 */
.dropdown-toggle .caret {
    transition: transform 0.3s ease;
}

.dropdown:hover .dropdown-toggle .caret,
.dropdown.open .dropdown-toggle .caret {
    transform: rotate(180deg);
}