/* ===== 主导航 ===== */
.navbar-main {
    background-color: #fff;
    padding: 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.03);
    border-bottom: 1px solid #e5e5e5;
}
.navbar-nav .nav-link {
    color: #333;
    font-size: 16px;
    padding: 16px 22px !important;
    position: relative;
    transition: color 0.3s;
    text-decoration: none !important;
}
.navbar-nav .nav-link:hover,
.navbar-nav .nav-link.active {
    color: #f78b28;
}
.navbar-nav .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 3px;
    background-color: #f78b28;
    transition: width 0.3s;
}
.navbar-nav .nav-link:hover::after,
.navbar-nav .nav-link.active::after {
    width: 80%;
}

@media (max-width: 991.98px) {
    .navbar-main {
        position: relative;
    }
    #mainNav.navbar-collapse {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: #fff;
        z-index: 999;
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.08);
    }
    .navbar-nav .nav-link {
        text-align: center;
    }
    .navbar-toggler-icon {
        background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='%23333333' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
    }
}

@media (max-width: 768px) {

}

@media (max-width: 576px) {

}