IMO better UI behavior would involve only the color change and not any movement of actual content; which is a bit jarring. you can accomplish this by instead using the outline CSS property instead of border. or make the content in question always have a border that is same color as the backdrop but that changes on hover). and finally, another tek is to make the parent div of said content position:relative and then use a secondary child div of said parent and have that your color'ed effect; set to position:absolute and position it to where you want it ie- left and width of 5px or whatever with background color. oh and it will need a z-index so it positions above said content.