html,body{
    height: 100vh;
}

html{
    overflow: hidden;
}

body {
    margin: 0;
    background-image: url(../image/bg.jpg);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    position: relative;
    z-index: 1;
}

/* 透明度遮罩层 */
body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: white;
    opacity: 0.8;
    z-index: -1;
}

.header {
    display: flex;
    flex-direction: row;
    width: 100%;
    height: 60px;
    position: fixed;
    top: 0;
    border-bottom: 1px solid #cacaca;
    background-color: #fafafa3b;
}

.header .logo {
    flex: 0 0 auto;
    width: 200px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.header .logo a {
    color: #1e9fff;
    font-size: 20px;
}

.header .label {
    flex: 1 1 auto;
    height: 60px;
}

.header .menu {
    flex: 0 0 auto;
    width: 420px;
    height: 60px;
}