Sizing and positioning
.pos-f-t class can be used to easily position elements at the top of the viewport and make them as wide as the viewport. Be sure you understand the ramifications of fixed-position elements within your project. Here’s how the class is defined:
Width and height
Easily make an element as wide or as tall as its parent using the
.h-100 utility classes.
<img class="w-100" src="..." alt="Width = 100%">
<div style="height: 100px; background-color: rgba(255,0,0,0.1);"> <div class="h-100" style="width: 100px; background-color: rgba(0,0,255,0.1);">Full height</div> </div>