How can I select only first three elements with the :nth-child() selector?
:nth-child()
You can do it like this:
section > figure:nth-child(-n+3) { border: 1px solid; }
<section> <figure>1</figure> <figure>2</figure> <figure>3</figure> <figure>4</figure> <figure>5</figure> <figure>6</figure> </section>