W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<head>
<style>
#borderimg1 {
  border: 10px solid transparent;
  padding: 15px;
  border-image: url(border.png) round;
  border-image-slice: 10%;
}

#borderimg2 {
  border: 10px solid transparent;
  padding: 15px;
  border-image: url(border.png) round;
  border-image-slice: 20%;
}

#borderimg3 {
  border: 10px solid transparent;
  padding: 15px;
  border-image: url(border.png) round;
  border-image-slice: 30%;
}
</style>
</head>
<body>

<h1>The border-image-slice Property</h1>

<p id="borderimg1">border-image-slice: 10%;</p>
<p id="borderimg2">border-image-slice: 20%;</p>
<p id="borderimg3">border-image-slice: 30%;</p>

<p>Here is the image used:</p>
<img src="border.png">

<p><strong>Note:</strong> Internet Explorer 10, and earlier versions, do not support the border-image-slice property.</p>

</body>

</html>