How to make a vertical progress bar showing what percentage of the article you have read on the page?

The article discusses how to create a reading scroll progress bar for your blog using JavaScript and CSS. This progress bar is useful because it allows readers to track how far they've come in an article. The author provides a step-by-step guide on how to implement this effect on your website, making it an ideal solution for bloggers looking to enhance user experience. We start by creating a basic HTML structure that will then be complemented with CSS styles. Next, by using JavaScript, we dynamically calculate the height of the document and the distance scrolled by the user, which allows us to update the progress bar appropriately. This clever addition will improve interaction with the content and increase reader engagement. The article also mentions various customization options for the appearance of the bar, granting the freedom to personalize this element on your blog.