<body>
<ul id="ul1">
<li class="kk"></li>
<li></li>
<li></li>
<li></li>
<li></li>
</ul>
<ul id="ul2">
<li class="red"></li>
<li></li>
<li></li>
<li></li>
<li></li>
</ul>
<style>
body,h1,h2,h3,h4,h5,h6,p,a,img,input,ul,li,ol,dl,dt,dd,figure,figcaption{ padding:0; margin:0}
*{ box-sizing:border-box;user-select: none;}
header,footer,article,section,aside,nav,figure,figcaption,main,summary,details{ display:block;}
ul,ol{ list-style:none;}
img{ display:block; border:0}
input{ outline:none;}
body,html{ height:100%;}
body{color:#000; font-family:"微软雅黑";}
html{font-size:26.67vw;}
a{ text-decoration:none; color:#000;}
::-webkit-scrollbar{
display:none;
}
#ul2 .red{
display: block;
}
#ul1 .kk{
border-bottom: 10px solid orange;
}
#ul1{
display: flex;
}
#ul1 li{
width: 20%;
height: 30px;
}
#ul1 li:nth-child(2n+1){
background: #000;
}
#ul1 li:nth-child(2n){
background: #cccccc;
}
#ul2 li{
width:100%;
height:100px;
display: none;
}
#ul2 li:nth-child(2n){
background: red;
}
#ul2 li:nth-child(2n+1){
background: blue;
}
</style>
<script>
$(document).ready(function(){
var now = $("#ul2 li");
$("#ul1 li").click(function(){
var idx = $(this).index();
$(now[idx]).addClass("red").siblings().removeClass("red");
$(this).addClass("kk").siblings().removeClass("kk");
})
})
</script>