Joke Collection Website - Joke collection - What is the file bootstrap.css.map used for?

What is the file bootstrap.css.map used for?

This is the source mapping file.

Because bootstrap is written in less, less will be compiled into css and displayed on the page.

But there is one problem. What you see in the browser is the line number of css, and you edit fewer files, which is difficult to match.

At this time, with the source map, it is very convenient to display it less directly in the browser.