html - How to add space to the bottom of a page without <br> -

how can add space bottom of web page, 100 pixels, without using multiple <br> tags? right have this:

<br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br> 

and can annoying read when i'm looking through code. there way without <br>, maybe css?

you can use margin-bottom, use class when ever want keep 100px gap

.bottom {     margin-bottom:100px; }