主体结构
rush:xhtml;">
样式
li{
display:block;
}
#traffic span{
display:inline-block;
width:50px;
height:50px;
background-color:gray;
margin:5px;
border-radius:50%;
float:left;
}
#traffic.stop li:nth-child(1) span{
background-color:yellow;
}
#traffic.wait li:nth-child(2) span{
background-color:red;
}
#traffic.pass li:nth-child(3) span{
background-color:green;
}
js代码
利用定时器改变类名
rush:js;">
const traffic = document.getElementById("traffic");
(function reset(){
traffic.className = "wait";
setTimeout(function(){
traffic.className = "stop";
setTimeout(function(){
traffic.className = "pass";
setTimeout(reset,2000);
},2000);
},2000);
})();