Create a horizontally scrolling component. By that I mean a container with several items in line that you must scroll horizontally to see. Use
overflow properties to accomplish this. Try to make it responsive in that it adapts to different screen widths, but still has enough content to scroll.
The content of the items can be anything at all, even empty padding, but style them in a way that it's clear to see their borders and/or spacing.
NOTE: With overflowing content, most browsers do not take into account the margins and padding after the final item. Don't worry if you have trouble getting white space around the final item in your scroll area.