<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
.verticalLine {
border-left: 4px solid #4b42f5;
height: 200px;
position: absolute;
left: 50%;
margin-left: -3px;
top: 0;
}
</style>
</head>
<body>
<div class="verticalLine"></div>
</body>
</html>