javascript - Issues about the priority of styles added by className.
I made a simple calendar, made with ul li, and then I first used css to use the selector #p ul li to add a background: black; then, I used the className of js to add a background to all li The style is active, and the background priority is not as high as it originally was. So what should I do to raise the priority to the highest level? -- Semi-finished code. .
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
*{
margin: 0;
padding: 0;
}
#main{
width: 500px;
height: 300px;
}
#main ul li{
float: left;
width: 80px;
height: 80px;
background-color: gray;
list-style: none;
margin: 20px;
}
#main p{
width: 300px;
height: 80px;
border: 1px solid red;
position: absolute;
top:350px;
}
.active{
background:red;
color: #fff;
cursor: pointer;
}
</style>
<script>
window.onload=function()
{
var op = document.getElementById('main');
var oLi = op.getElementsByTagName('li');
var ap = op.getElementsByTagName('p')[0];
var month = ['a','b','c','d','e','f','g','h','i','j','k','l']
for(var i=0;i<oLi.length;i++)
{
oLi[i].index=i;
oLi[i].onmouseover=function()
{
for(var i=0;i<oLi.length;i++)
{
oLi[i].className="";
}
this.className="active";
ap.innerHTML = (this.index+1)+month[this.index];
}
}
}
</script>
</head>
<body>
<p id="main">
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
<li>6</li>
<li>7</li>
<li>8</li>
<li>9</li>
<li>10</li>
<li>11</li>
<li>12</li>
</ul>
<p></p>
</p>
</body>
</html>