Center Div inside another (100% width) div

Question

Quite a \"simple\" problem here and not sure why it\'s being so complicated.

1. Have a 100% (width) sized div.
2. Have another div positioned in the middle

Answer 1

for detail info, let's say the code below will make a div aligned center:

margin-left: auto;
margin-right: auto;

or simply use:

margin: 0 auto;

but bear in mind, the above CSS code only works when you specify a fixed width (not 100%) on your html element. so the complete solution for your issue would be:

.your-inner-div {
      margin: 0 auto;
      width: 900px;
}