You can give any element “rounded corners” by applying a border-radius through CSS. You’ll only notice if there is a color change involved. For instance, if the element has a background-color or border that is different than the element it’s over. Simple examples:
#example-one {
border-radius: 10px;
background: #BADA55;
}
#example-two {
border-radius: 10px;
border: 3px solid #BADA55;
}