Now, suppose you had more than one category of thumbnails you wished to display on your page, and you want to group them visually, with a background and/or border. Simply enclose them in a container DIV: div.container { border: 2px dashed #333; background-color: #ffe; } However when we do this we run into a problem. When you float an element with CSS, it no longer takes up any “space” and the back
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