JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <a class="tooltips" href="https://evernote.com">
    Hi Christine!
    <span>Blarghhhh boo!</span>
  </a>
</div>

CSS

.container {
  position: relative;
  margin: auto;
  width: 500px;
  line-height: 150px;
  text-align: center;
}

a.tooltips {
  position: relative;
  display: inline;
}
a.tooltips span {
  position: absolute;
  width: 140px;
  
  color: #FFFFFF;
  background: #000000;
  height: 30px;
  line-height: 30px;
  text-align: center;
  visibility: hidden;
  border-radius: 6px;
  border: 1px solid red;
}
a.tooltips span:before, /*new*/
a.tooltips span:after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  margin-left: -8px;
  width: 0; 
  height: 0;
  border-left: 1px solid green; /*new*/
  
  /*
   * THIS CODE MAKES THE TRIANGLE
   */
  border-top: 8px solid #000000;
  border-right: 8px solid transparent;
  border-left: 8px solid transparent;
}
a.tooltips span {
  visibility: visible;
  opacity: 0.8;
  bottom: 30px;
  left: 50%;
  margin-left: -76px;
  z-index: 999;
}