css 實作多行展開收起自動隐藏（全相容）
學習筆記
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
.flex {
display: flex;
}
input {
display: none;
}
.box {
/* display: -webkit-box;
-webkit-line-clamp: 2;
text-overflow: ellipsis;
-webkit-box-orient: vertical; */
max-height: 40px;
overflow: hidden;
line-height: 20px;
position: relative;
transition: .3s max-height;
}
.box::after {
content: '...';
width: 999vw;
height: 999vw;
position: absolute;
box-shadow: inset calc(100px - 999vw) calc(30px - 999vw) 0 0 #fff;
margin-left: -100px;
}
input:checked + .box::after {
visibility: hidden;
}
.box::before {
content: '';
width: 0;
height: 100%;
margin-bottom: -20px;
float: right;
}
.box .btn {
float: right;
background: blue;
color: #fff;
height: 20px;
border: none;
clear: both;
position: relative;
margin-left: 22px;
}
.box .btn::before {
content: '...';
position: absolute;
line-height: 20px;
left: -8px;
color: #000;
transform: translateX(-100%);
}
.box .btn::after {
content: '展開';
display: block;
padding: 0 5px;
height: 20px;
background-color: aqua;
line-height: 20px;
}
input:checked + .box {
max-height: 100px;
}
input:checked + .box .btn::after {
content: '收起';
}
input:checked + .box .btn::before {
visibility: hidden;
}
</style>
</head>
<body>
<div class="flex">
<input type="checkbox" id="btn">
<div class="box">
<label class="btn" for="btn"></label>我是純css實作的收起展開功能我是純css實作的收起展開功能我是純css實作的收起展開功能我是純css實作的收起展開功能我是純css實作的收起展開功能我是純css實作的收起展開功能
</div>
</div>
</body>
</html>
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