html - css伪元素不会显示

Question

我正在制作一个导航菜单(遵循教程)，并且为了制作导航图标我显然必须使用伪元素。正常情况下会很好，但这一次，他们根本不会出现......

我的代码有问题吗/有没有更好的方法来制作图标？

*,
*::before,
*::after {
    box-sizing: inherit;
    padding: 0;
    margin: 0;
}
body {
    padding: 0;
    margin: 0;
    background-color: #FFF
    -webkit-font-smoothing: antialiased;
}
a {
    color: hsla(37, 39%, 72%, 1.00);
    text-decoration: none;
}
li{
    list-style: none;
}
.header {
    width: 100vw;
    height: 100vh;
    display: block;
    background:url(img/background.jpg) no-repeat center center;
    background-size: cover;
    position: relative;
}
.logo {
    font-size: 4em;
    color: #FFF;
    line-height: 1.1;
    border: 1px solid #fff;
    border-radius: 100%;
    width: 80px;
    height: 80px;
    display: inline-block;
    padding: 5px;
    background-color: hsla(152, 40%, 20%, 1.00);
    margin: 50px 0 0 50px;
    cursor: pointer;
}
.nav-icon {
    width: 50px;
    height: 40px;
    display: block;
    background-color: transparent;
    position: absolute;
    top: 70px;
    right: 50px;
    cursor: pointer;
    -webkit-user-select: none;
    -moz-user-select: none;
    -o-user-select: none;
       user-select: none;
}
.nav-icon .icon {
    width: 50px;
    height: 2px;
    display: block;
    background-color: #333;
    position: absolute;
    top: 20px;
}

.nav-icon .icon::before 
.nav-icon .icon::after {
    content: "";
    width: 50px;
    height: 2px;
    display: block;
    background-color: #FFF
    position: absolute;
    height: 100%;
}

.nav-icon .icon::before {
    top: -10px;
}
.nav-icon .icon::after {
    top: 10px;
}

Answer 1

您在某些行中遗漏了分号 ; 和在

中遗漏了逗号 ,

.nav-icon .icon::before ,
.nav-icon .icon::after {
    content: "";
    width: 50px;
    height: 2px;
    display: block;
    background-color: #FFF
    position: absolute;
    height: 100%;
}

这解决了你正在寻找的问题