Using CSS you can customize the scroll bar or any website but it is not easy for everyone and also there are some browser compatibility issues. This tutorial is about a WordPress plugin which provides website a customizable, stylish & responsive scrollbar. See it live working here. Dewdrop Custom Scrollbar allows you to customize the frontend scroll bar and use you own custom colors, width, height, border, radius etc and it supports all major web browsers like Firefox, Chrome, Chromium, Opera etc.
To start using it in your WordPress site, first install and activate Dewdrop Custom Scrollbar plugin. After activation visit your admin area Dashboard -> Settings -> Dewdrop Custom Scrollbar Options page to configure the settings.
From its options page you can change your scrollbar color, you can also add html HEX color code. You can use a custom scrollbar width, height and radius in pixels. You can also also choose a custom scrollbar’s border color and width. Finally, save the changes and that’s it.