W3School TIY Editor

<!DOCTYPE html>
<html>
<head>
<style>
.masked {
  width: 150px;
  height: 150px;
  background: green;
  border: 30px solid blue;
  padding: 20px;
  -webkit-mask-image: url(/i/css/circle.svg);
  mask-image: url(/i/css/circle.svg);
  mask-size: 100% 100%;
}
.mask1 {
  mask-clip: border-box;  
}

.mask2 {
  mask-clip: content-box;  
}

.mask3 {
  mask-clip: padding-box;  
}

.mask4 {
  mask-clip: fill-box;  
}

.mask5 {
  mask-clip: stroke-box;  
}
</style>
</head>
<body>

<h3>设置 mask-clip: border-box:</h3>
<div class="masked mask1">
  <img src="/i/photo/beijing.jpg" alt="Beijing" width="600" height="400">
</div>

<h3>设置 mask-clip: content-box:</h3>
<div class="masked mask2">
  <img src="/i/photo/beijing.jpg" alt="Beijing" width="600" height="400">
</div>

<h3>设置 mask-clip: padding-box:</h3>
<div class="masked mask3">
  <img src="/i/photo/beijing.jpg" alt="Beijing" width="600" height="400">
</div>

<h3>设置 mask-clip: stroke-box:</h3>
<div class="masked mask5">
  <img src="/i/photo/beijing.jpg" alt="Beijing" width="600" height="400">
</div>

</body>
</html>