<style>
.fullscreen {
position: fixed!important;
top: 0!important;
left: 0!important;
width: 100%!important;
height: 100%!important;
margin: 0!important;
z-index: 100;
background-color: aquamarine;
border-radius: 50%;
box-shadow:blueviolet;
display: flex;
align-items: center;
justify-content: center;
}
.divStyle {
width: 100px;
height: 100px;
background-color: aquamarine;
border-radius: 50%;
box-shadow:blueviolet;
display: flex;
align-items: center;
justify-content: center;
}
</style>
<body>
<div class="divStyle" onclick="bigscreen()" id='cc'>123</div>
</body>
</html>
<script>
function bigscreen() {
const obj = document.getElementById('cc')
obj.className = obj.className === 'fullscreen' ? 'divStyle' : 'fullscreen'
}
</script>
//主要代码
.fullscreen {
position: fixed!important;
top: 0!important;
left: 0!important;
width: 100%!important;
height: 100%!important;
margin: 0!important;
z-index: 100;
}