Two Column layout that is fully response to page resizing

Hello,

I have a section on a page that is essentially 2 columns of text.

I added this to base.css for Dawn theme:

.one-half-column-left {
width:48%;
float:left;
}

.one-half-column-right {
width:48%;
float:right;
}

@media only screen and (max-width: 600px) {
.one-half-column-left, .one-half-column-right,
.one-third-column, .one-third-column-last {
float:none;
width:100%;
margin-right:0;
}

and added html to the page.

For the desktop view, this is how it looks:

Is there a way to space the columns out horizontally so there is not a lot of padding on the left and right sides of the section?