Tailwind CSS class .-translate-y-1/2

<div class="bg-gray-300 h-64 w-8 m-2 mt-8 inline-flex"><div class="-translate-y-1/2 transform bg-teal-400 h-6 w-8 mt-auto text-center">-1/2</div></div>

.-translate-y-1/2 { --transform-translate-y: -50%; }