Colorbox images

I'm really liking the Beep Edition theme. I added some CSS to accommodate Colorbox images. When Colorbox is selected as the format for an image field with the following settings,

Content image style: Medium (220x220)
Colorbox image style: colorbox
Colorbox gallery type: Per post gallery
Colorbox caption: Automatic

the content image is displayed at 100% of the parent class, i.e., the 220 x 220 image is enlarged to fit the width of the container. I think this is because in html-base.scss we have:

img {
	display: block; 
	max-width: 100%; 
	width: 100%; 
	height: auto; 
}

Adding:

.colorbox { 
	img {
          width: inherit; 
	  border: none;
 	}
}

allows the image to be displayed at the 220 x 220 size (or whatever size the Content image style is defined to be).