JSFiddle - React, Tailwind, and code Playground

HTML

CSS created Triangle
<div class="main-link-active-triangle"></div>

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Browsercompare Screenshot
<br/><img src="http://i.imgur.com/vdmAf.png"/>

CSS

div.main-link-active-triangle {
    position:absolute;
    top:50px;
    left:50px;
    width:0px;
    height:0px;
    border-left: 55px solid transparent;
    border-right: 55px solid transparent;
    border-top: 15px solid #D5CDBA;
    background-color: #ff0000;
}