JSFiddle - React, Tailwind, and code Playground

HTML

<div id='borderone'></div>

CSS

#borderone {
    		border-top: 33px solid #354658;
    		border-left: 33px solid transparent;
    		border-right: 33px solid transparent;
    		margin: 0 auto;
    		min-width: 42px;
    	}