CSS center content within a div
Here’s an old bit of code that I found to position something centrally inside an element.
width: 400px; /* here you put the width that you need */
height: 200px; /* here you put the height that you need */
margin-left:-200px; /* this number always to be the width divided two in negative */
margin-top:-100px; /* this number always to be the height divided two in negative */