<div class="container">
  <div class="clip-text">
    Hello World
  </div>
</div>

.clip-text {
  background: url(http://i.giphy.com/fsULJFFGv8X3G.gif);
  background-size: cover;
  background-position: center;
  
  -webkit-background-clip: text;
  color: transparent; // set to transparent, otherwise won't see the background
  
  width: 300px;
  height: 100px;
  box-sizing: border-box;
  font-size: 58px;
  font-weight: bold;
  text-align: center;
  line-height: 100px;
  flex-shrink: 0;
}