JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">

  <div class="box1">
    <div class="content">
      <p>HEJ</p>
    </div>
    <div class="buttons">
        <button>ONEONE</button>
        <button>TWOTWO</button>
    </div>
  </div> 
  
    <div class="box2">
    <div class="content">
      <p>HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ HEJ </p>
    </div>
    <div class="buttons">
        <button>ONEONE</button>
        <button>TWOTWO</button>
    </div>
  </div> 
  
    <div class="box3">
    <div class="content">
      <p>HEJ</p>
    </div>
    <div class="buttons">
        <button>ONEONE</button>
        <button>TWOTWO</button>
    </div>
  </div> 

</div>

CSS

.container {
  width: 600px;
  display:flex;
  flex-flow: row;
  border: 2px solid red;
}

.box1, .box2, .box3 {
  width: 100%;
  border: 1px solid blue;
  display: flex;
  flex-flow: column;
  size: 100px;
}

.content {
  text-align:center;
}

.buttons {
  display:flex;
  flex-flow: column;
}