This is a js page scrollbar plug-in Three files are introduced when using :(fill in the path by yourself)

<link type="text/css" href=" The path /jquery.jscrollpane.css" rel="stylesheet" media="all" />
<script type="text/javascript" src=" The path /jquery.mousewheel.js"></script>
<script type="text/javascript" src=" The path /jquery.jscrollpane.min.js"></script>

Then add a method to the container that needs to add the scroll bar, and we’re done

$(function(){
$("#contentDiv").jScrollPane();
})

Great! Ps: if you want to change the default style of the scrollbar, you can open the jquery.jscrollpane.css file and change it Of course, this is a plug-in for jquery, and the original jquery package should be included before the plug-in package, which is omitted in this article.