#header-placeholder{
    height: 70px;
   }
   a {
                text-decoration: none;
                color: inherit;
                transition: color 0.3s;
            }

            ul {
                list-style: none;
            }
/* ================= 公共导航栏样式 ================= */
.btnOpen{
    cursor: pointer;
}
/* --- 顶部导航栏 --- */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    background-color: #ffffff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 6%;
    z-index: 1000;
    min-width: 1300px;
    /* 底部边框 + 阴影效果 */
    border-bottom: 1px solid #eaeaea;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12), 0 1px 3px rgba(0, 0, 0, 0.08);
}

.logo img {
    height: 35px;
    display: block;
}

nav ul {
    display: flex;
    gap: 28px;
}

nav a {
    font-size: 15px;
    color: #333;
    font-weight: 500;
    padding: 5px 0;
    position: relative;
    transition: color 0.3s;
}

nav a:hover,
nav a.active {
    color: #b71c1c;
}

/* --- 下拉箭头样式 --- */
.has-arrow {
    position: relative;
}

.has-arrow::after {
    content: '';
    display: inline-block;
    width: 8px;
    height: 8px;
    border-right: 2px solid #666;
    border-bottom: 2px solid #666;
    transform: rotate(45deg);
    margin-left: 6px;
    margin-bottom: 2px;
    transition: border-color 0.3s;
}

.has-arrow:hover::after {
    border-color: #b71c1c;
}

.has-arrow.active::after {
    border-color: #b71c1c;
}

/* --- 下拉菜单样式 --- */
.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    width: 260px;
    background-color: #fff;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-radius: 4px;
    padding: 15px 0;
    z-index: 100;
}

.dropdown-menu li {
    padding: 12px 20px;
    border-bottom: 1px solid #f0f0f0;
}

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

.dropdown-menu a {
    display: block;
    font-size: 14px;
    color: #555;
    line-height: 1.5;
}

.dropdown-menu a:hover {
    color: #b71c1c;
    background-color: #fafafa;
}

/* --- 下拉菜单交互逻辑 --- */
/* 仅支持 hover 的设备（PC/鼠标）才通过悬停展开 */
@media (hover: hover) {
    .nav-item:hover .dropdown-menu {
        display: block;
    }
}

/* 不支持 hover 的设备（手机/平板）通过 JS 的 .dropdown-open 展开 */
.nav-item.dropdown-open .dropdown-menu {
    display: block;
}

.nav-item {
    position: relative;
}


/* ================= 公共页脚样式 ================= */

/* --- 页脚区域 --- */
.site-footer {
    background-color: #1f2936;
    color: #aaa;
    padding: 60px 15% 20px;
    font-size: 14px;
    min-width: 1300px;
}

.footer-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 30px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 20px;
}

.footer-logo {
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-red);
    letter-spacing: 1px;
    font-family: "SimSun", serif;
}

.footer-logo span {
    color: #fff;
    font-size: 18px;
    margin-left: 10px;
    font-weight: normal;
}

.footer-info {
    text-align: right;
    line-height: 1.8;
}

.footer-bottom {
    text-align: center;
    color: #888;
}

.footer-bottom a {
    color: #888;
    margin: 0 10px;
}

.footer-bottom a:hover {
    color: #fff;
}