/* ============================================
   腾隍纽扣 - 响应式导航栏样式
   ============================================ */

/* 定义阿里巴巴普惠体 */
@font-face {
    font-family: 'AlibabaPuHuiTi';
    src: url('../fonts/alibbapht/AlibabaPuHuiTi-3-75-SemiBold.woff2') format('woff2'),
        url('../fonts/alibbapht/AlibabaPuHuiTi-3-75-SemiBold.woff') format('woff'),
        url('../fonts/alibbapht/AlibabaPuHuiTi-3-75-SemiBold.ttf') format('truetype');
    font-weight: 900;
    font-style: normal;
    font-display: swap;

}

:root {
    --primary-color: #6a79d9;
    --bg-white: #ffffff;
    --text-dark: #333333;
    --transition-speed: 0.3s;
    --nav-font: 'AlibabaPuHuiTi', sans-serif;
}

/* 导航栏容器 */
.navbar {
    background-color: var(--bg-white);
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 1050;
    padding: 10px;
    transition: all var(--transition-speed);
    font-family: var(--nav-font);
        letter-spacing: 0.7pt;
    word-spacing: 2.2pt;
}

.navbar-brand img {
    height: 70px;
    /* 调整Logo高度 */
    width: auto;
    transition: transform var(--transition-speed);
}

.navbar-brand:hover img {
    transform: scale(1.05);
}

/* 移除Bootstrap默认的下拉箭头 */
.dropdown-toggle::after {
    display: none !important;
}

/* 导航项文字样式 */
.nav-link {
    color: var(--text-dark) !important;
    font-weight: 500;
    font-size: 1.15rem;
    /* 字号增大 */
    padding: 1.5rem 1.2rem !important;
    /* 增加水平间距 */
    position: relative;
    transition: color var(--transition-speed);
}

.nav-link:hover,
.nav-link.show,
.nav-link.active {
    color: var(--primary-color) !important;
}

/* 简洁的下划线动画 */
.nav-link::after {
    content: '';
    position: absolute;
    bottom: 1rem;
    /* 调整位置 */
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
    transition: width 0.3s ease-in-out;
}

.nav-link:hover::after,
.nav-link.active::after,
.nav-link.show::after,
.dropdown:hover > .nav-link::after {
    width: 40%;
    /* 短条效果 */
}

/* 导航栏滚动后的样式 */
.navbar-scrolled {
    padding: 0.2rem 0;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

/* 下拉菜单基础样式 */
.dropdown-menu {
    border: none;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    border-radius: 8px;
    padding: 0.5rem 0;
    margin-top: 0;
    animation: fadeInDown 0.3s ease;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.dropdown-item {
    padding: 0.8rem 1.5rem;
    font-size: 1.05rem;
    /* 字号增大 */
    color: var(--text-dark);
    transition: all var(--transition-speed);
}

.dropdown-item:hover {
    background-color: rgba(106, 121, 217, 0.1);
    color: var(--primary-color);
    padding-left: 1.8rem;
}

/* 语言切换器 */
.lang-switcher {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-left: 1.5rem;
}

.lang-divider {
    color: #ddd;
    font-weight: 300;
    font-size: 1.1rem;
}

.lang-link {
    text-decoration: none;
    color: var(--text-dark);
    font-size: 1.05rem;
    /* 字号增大 */
    transition: color var(--transition-speed);
}

.lang-link:hover,
.lang-link.active {
    color: var(--primary-color);
}

/* 响应式汉堡按钮自定义 */
.navbar-toggler {
    border: none;
    padding: 0;
}

.navbar-toggler:focus {
    box-shadow: none;
}

.navbar-toggler-icon {
    background-image: none;
    position: relative;
    width: 24px;
    height: 24px;
}

.navbar-toggler-icon::before,
.navbar-toggler-icon::after,
.navbar-toggler-icon span {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--text-dark);
    transition: all 0.3s ease;
}

.navbar-toggler-icon::before {
    top: 4px;
}

.navbar-toggler-icon span {
    top: 11px;
}

.navbar-toggler-icon::after {
    top: 18px;
}

/* 针对手机端汉堡按钮的微调 */
.navbar-toggler {
    margin-right: 0.5rem;
}

/* 展开时的动画 */
.navbar-toggler[aria-expanded="true"] .navbar-toggler-icon::before {
    transform: rotate(45deg);
    top: 11px;
}

.navbar-toggler[aria-expanded="true"] .navbar-toggler-icon span {
    opacity: 0;
}

.navbar-toggler[aria-expanded="true"] .navbar-toggler-icon::after {
    transform: rotate(-45deg);
    top: 11px;
}

/* 手机端样式调整 - 更加极简、清爽 */
@media (max-width: 991.98px) {
    .navbar {
        padding: 0.5rem 0;
        overflow-x: hidden; /* 防止导航展开时溢出 */
    }

    .navbar-collapse {
        overflow-x: hidden; /* 确保折叠菜单不溢出 */
        max-width: 100vw; /* 限制最大宽度 */
    }

    .navbar-brand img {
        height: 50px;
        /* 手机端Logo稍微调小，避免占位过多 */
    }

    .navbar-collapse {
        background: var(--bg-white);
        padding: 1rem 0.5rem;
        border-top: 1px solid #f0f0f0;
        /* 给展开菜单加个微弱的分割线 */
        margin-top: 0.5rem;
    }

    .nav-item {
        width: 100%;
    }

    .nav-link {
        padding: 1rem 1.5rem !important;
        /* 增加点击区域和垂直间距，解决拥挤感 */
        font-size: 1.1rem !important;
        border-bottom: 1px solid #f9f9f9;
        /* 菜单项之间加极浅分割线 */
    }

    /* 移除手机端所有复杂的下划线动画 */
    .nav-link::after {
        display: none !important;
    }

    /* 手机端下拉菜单优化：去掉边框和阴影，仅做缩进 */
    .dropdown-menu {
        box-shadow: none;
        background-color: #fafafa;
        /* 稍微深一点点的底色区分主菜单 */
        padding: 0;
        margin: 0;
        border-radius: 0;
        border: none;
    }

    .dropdown-item {
        padding: 0.8rem 2.5rem !important;
        /* 增加缩进 */
        font-size: 1rem !important;
        border-bottom: 1px solid #f0f0f0;
    }

    .dropdown-item:last-child {
        border-bottom: none;
    }

    /* 语言切换器在手机端也做简化 */
    .lang-switcher {
        margin: 1.5rem 1.5rem 0.5rem;
        padding-top: 1rem;
        justify-content: flex-start;
        border-top: none;
        /* 移除之前可能存在的分割线 */
    }

    .lang-divider {
        margin: 0 0.5rem;
        color: #eee;
    }
}

/* 桌面端 Hover 展开逻辑通过 JS 实现，CSS 配合透明度 */
@media (min-width: 992px) {
    .dropdown:hover>.dropdown-menu {
        display: block;
    }
}