W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<head>
<style>
.mask3 {
  width: 600px;
  height: 400px;
  background: green;
  border: 20px solid red;
  padding: 50px;
  -webkit-mask-image: url(w3logo.png);
  mask-image: url(w3logo.png);
  -webkit-mask-size: 70%;
  mask-size: 70%;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;    
  -webkit-mask-origin: padding-box;
  mask-origin: padding-box;  
}

.mask4 {
  width: 600px;
  height: 400px;
  background: green;
  border: 20px solid red;
  padding: 50px;
  -webkit-mask-image: url(w3logo.png);
  mask-image: url(w3logo.png);
  -webkit-mask-size: 70%;
  mask-size: 70%;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;    
  -webkit-mask-origin: margin-box;
  mask-origin: margin-box;  
}
</style>
</head>
<body>

<h1>The mask-origin Property</h1>

<h3>Set mask-origin: padding-box:</h3>
<div class="mask3">
  <img src="img_5terre.jpg" alt="Cinque Terre" width="600" height="400">
</div>

<h3>Set mask-origin: margin-box:</h3>
<div class="mask4">
  <img src="img_5terre.jpg" alt="Cinque Terre" width="600" height="400">
</div>

<h3>Original image:</h3>
<img src="img_5terre.jpg" alt="Cinque Terre" width="600" height="400">

</body>

</html>

​x
 
<!DOCTYPE html><html><head><style>.mask3 {  width: 600px;  height: 400px;  background: green;  border: 20px solid red;  padding: 50px;  -webkit-mask-image: url(w3logo.png);  mask-image: url(w3logo.png);  -webkit-mask-size: 70%;  mask-size: 70%;  -webkit-mask-repeat: no-repeat;  mask-repeat: no-repeat;      -webkit-mask-origin: padding-box;  mask-origin: padding-box;  }​.mask4 {  width: 600px;  height: 400px;  background: green;  border: 20px solid red;  padding: 50px;  -webkit-mask-image: url(w3logo.png);  mask-image: url(w3logo.png);  -webkit-mask-size: 70%;  mask-size: 70%;  -webkit-mask-repeat: no-repeat;  mask-repeat: no-repeat;      -webkit-mask-origin: margin-box;  mask-origin: margin-box;  }</style></head><body>​<h1>The mask-origin Property</h1>​<h3>Set mask-origin: padding-box:</h3><div class="mask3">  <img src="img_5terre.jpg" alt="Cinque Terre" width="600" height="400"></div>​<h3>Set mask-origin: margin-box:</h3>