<div class="hearts">
</div> 

.hearts {
  border: 20px solid pink;
  border-image-source: url(https://s3-us-west-2.amazonaws.com/s.cdpn.io/652/hearts-border-image.png);
  border-image-slice: 20 22;
  border-image-repeat: round;
}
/* styling for Pen, unrelated to border-image */

* {
  box-sizing: border-box;
}

body {
  background-color: #1D1F1F;
}

div {
  width: 40vw;
  height: 40vh;
  margin: 4em auto;
}