JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
  <div class="centered">
    <div class="rowOne">
      <div class="telefoonButton">
        <a href="tel:0652333817" title="Bel ons"><img src="http://eightytwenty.nl//wordpress/wp-content/uploads/2015/12/phoneNook.png" alt="telefoon" class="Center-Block Absolute-Center is-Image"></a>
      </div>
      <div class="mailButton">
        <a href="mailto:slotenmakerdenhaag@gmail.com" title="Mail ons"><img src="http://eightytwenty.nl/wordpress/wp-content/uploads/2015/12/mailNook.png" alt="mail" class="Center-Block Absolute-Center is-Image"></a>
      </div>
    </div>
    <div class="rowTwo">
      <div class="infoButton">
        <a href="contact" title="Bel ons"><img src="http://eightytwenty.nl//wordpress/wp-content/uploads/2015/12/infoNook.png" alt="telefoon" class="Center-Block Absolute-Center is-Image"></a>
      </div>
      <div class="contactButton">
        <a href="contact#contact" title="Mail ons"><img src="http://eightytwenty.nl//wordpress/wp-content/uploads/2015/12/contactNook.png" alt="mail" class="Center-Block Absolute-Center is-Image"></a>
      </div>
    </div>
  </div>
</div>

CSS

.wrapper {
    height: 100vh;
    margin: 0 auto;
    position: relative;
    width: 100%;
}
.rowOne, .rowTwo {
    width: 50%;
    height: auto;
    float: left;
}
.Absolute-Center.is-Image {
  height: auto;
}

.centered {
  position: absolute;
  transform: translate(-50%, -50%);
  top: 50%;
  left: 50%;
  text-align: center;
}

.Absolute-Center.is-Image img {
  width: 50%;
  height: auto;
}