<!DOCTYPE html>
<html lang="ko">
<head>
<title> 13.zindex </title>
<style>
#aa{
background-color: red;
width: 100px;
height: 100px;
position: absolute;
left: 0;
top: 0;
z-index: 30;
}
#bb{
background-color: green;
width: 80px;
height: 200px;
position: absolute;
left: 0;
top: 0;
z-index: 5;
}
#cc{
background-color: cyan;
width: 60px;
height: 300px;
position: absolute;
left: 0;
top: 0;
z-index: 1;
}
</style>
</head>
<body>
<!-- 참조 https://www.w3schools.com/css/css_z-index.asp -->
<!-- 레이어 순서 정하기( 가장 큰 수가 위로, 레이어 순서값은 음수도 허용) -->
<div id="aa"></div>
<div id="bb"></div>
<div id="cc"></div>
</body>
</html>
