JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <h1>
        MyTitle
  </h1>
</div>

<h1 class="btlined">
  Some Title  
</h1>

CSS

.container{
  display: flex;
  justify-content: flex-start;
  align-items: flex-end;
  box-shadow:inset 0 -3px 0 blue;
  background:white;
}
.container h1 {
  margin:0;
  background:inherit;
}
.btlined {
  display:flex;
}
.btlined:after {
  content:'';
  border-bottom:solid blue;
  flex:1;
}