JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
    <div class="element">Content</div>
</div>

CSS

.container {
}

.element {
    position:relative;
    margin:10.3px;
    width:200px;
    height:20.3px;
    background-color:#ad0c38;
}

.element:before {
    
    content: "";
    display: block;
    height: 0;
    width: 0;
    border: 10px solid #ad0c38;
    border-right-color: transparent;
    border-bottom-color: transparent;
    position: absolute;
    bottom: 0px;
    right: -20px;
}