header {
    background: #3a67b1;
    color: #fff;
    padding: 10px 0;
    top: 0;
    position: sticky !important; 
    width: 100%;
    height: 70px;
    z-index: 500;
    border-bottom: rgba(0, 0, 0, 0.25) solid 5px;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 80%;
    height: 70px;
    margin: 0 auto;
}

header .jv {
    width: fit-content;
    display: flex;
    flex-wrap: nowrap;
    align-items: center;
    height: 65px;
}

header img {
    width: 65px;
    height: 65px;
    background-color: white;
    border-radius: 10px;
    margin: 0 10px;
}

header h1 {
    margin: 0;
    font-size: 40px;
    white-space: nowrap;
}

header nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
}

.hamburger {
    display: none;
    cursor: pointer;
    font-size: 30px;
}


@media (max-width: 1100px) {
    /* 隐藏导航栏 */
    header nav ul {
        display: none;
        flex-direction: column;
        width: fit-content;
        height: 100vh;
        background-color: #3a68b1ef;
        position: absolute;
        padding: 10px 10px;
        top: 100%;
        left: 0;
    }
    
    /* 显示汉堡菜单按钮 */
    .hamburger {
        position: relative;
        padding: 3% 10%;
        display: block;
        z-index: 5;
    }
    
    /* 显示汉堡菜单时，导航项纵向排列 */
    header nav ul.active {
        display: flex;
    }
    /* 桌面端的 active 链接样式 */


    header nav ul.active li {
        margin: 10px 0;
    }
    header nav ul.active .dropdown a li{
        color: #000;
        margin: unset;
        padding: unset;
        padding: 5px 0px 5px 15px;
        font-size: 16px;
    }
    header ul.active .dropdown {
        width: 200%;
        display: none;
        position: absolute;
        top: 115%;
        height: fit-content;
        background-color: #ffffff;
        border-radius: 15px;
        z-index: 10;
        transform: translateX(100px);
    }
}
/* 桌面端的 active 链接样式 */
header nav a.active {
    background-color: #ffffff !important; /* 强制应用白色背景 */
    color: #000 !important; /* 强制应用黑色文字 */
    border-radius: 3px;
}

/* 移动端汉堡菜单的 active 链接样式 */
@media (max-width: 1100px) {
    header nav ul.active a.active {
        background-color: #ffffff !important; /* 强制应用白色背景 */
        color: #000 !important; /* 强制应用黑色文字 */
        border-radius: 3px;
        width: 100%;
    }
}


header nav li {
    margin-left: 1rem;
    position: relative;
}

header nav a {
    color: #fff;
    text-decoration: none;
    padding: 7px 10px 7px 10px;
    z-index: 2;
    white-space: nowrap;
}

header .dropdown {
    width: 250%;
    display: none;
    position: absolute;
    top: 115%;
    left: 0;
    background-color: #ffffff;
    border-radius: 15px;
    z-index: 0;
}

header nav .dropdown a li{
    color: #000;
    margin: unset;
    padding: unset;
    padding: 5px 0px 5px 15px;
    font-size: 16px;
}
header nav a {
    font-size: 16px;
}

header nav li:hover > .dropdown {
    display: block;
}


header nav ul li::after {
    content: "";
    height: 133%;
    width: 0;
    background: rgba(202, 202, 202, 0.555);
    position: absolute;
    left: 0;
    bottom: -5px;
    border-radius: 3px;
    /* transition: width 0.5s ease-in-out; */
    z-index: -2;
}

header nav ul li:hover::after {
    width: 100%;
}


header nav a.active {
    background-color: #ffffff !important; /* 强制应用白色背景 */
    color: #000 !important; /* 强制应用黑色文字 */
    border-radius: 3px;
    width: 100%;
}

footer .container {
    width: 80%;
    margin: 0 auto;
}

footer {
    background: #407aac;
    color: #fff;
    text-align: center;
    padding: 1rem 0;
}


@media (max-width: 590px) {
    header h1 {
        font-size: 35px;
    }
}

@media (max-width: 520px) {
    header h1 {
        white-space: wrap;
        font-size: 20px;
    }
}