We might want to center a page or part of a page so that everything is aligned nicely in the center. When we want to center a page, we can put all the contents in a container div and give it a specific width and margin.

.container {
width: 1200px;
margin: 0 auto;
}


For a responsive site, we can use em or % for width instead of px. So it would be something like the following:

.container {
width: 80em;
margin: 0 auto;
}