I would do this with some positioning absolute , border and :hover .
HTML example:
<div class="top"> Technology <div> Extra options </div> </div>
CSS example:
.top { background: grey; border: 1px solid purple; position: relative; } .top > div { background: grey; border: 1px solid purple; position: absolute; left: -1px; top: 28px; z-index: -1; display: none; } .top:hover { border-bottom: 0; } .top:hover > div { display: block; }
Here is a fiddle for you with even more style.
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