<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
ul, #myUL {
list-style-type: none;
}
#myUL {
margin: 0;
padding: 0;
}
.caret {
cursor: pointer;
user-select: none; /* Safari 3.1+ */
-moz-user-select: none; /* Firefox 2+ */
-ms-user-select: none; /* IE 10+ */
user-select: none;
}
.caret::before {
content: "\25B6";
color: black;
display: inline-block;
margin-right: 6px;
}
.caret-down::before {
-ms-transform: rotate(90deg); /* IE 9 */
-webkit-transform: rotate(90deg); /* Safari */'
transform: rotate(90deg);
}
.nested {
display: none;
}
.active {
display: block;
}
</style>
</head>
<body>
<h2>Tree View</h2>
<p>A tree view represents a hierarchical view of information, where each item can have a number of subitems.</p>