图像的边界边界半径[重复]

Question

This question already has an answer here:

• Invert rounded corner in CSS? 11 answers
• CSS: borders with negative radius [duplicate] 2 answers

I want to create an inset border radius for an image using CSS if possible, I am posting this question because all of the solutions I found online so far were for text and using divs.

Here is what I wish to achieve:

Thanks!

Answer 1

One way:

<div class="container">
    <div class="dot1"></div>
       <div class="dot2"></div>
      <div class="dot3"></div>
       <div class="dot4"></div>
    <img src='http://placehold.it/400x300'>
</div>

CSS:

.container {
    position:relative;
    margin:50px auto;
    width:400px;
}
.dot1 {
    background-color:white;
    width:50px;
    height:50px;
    border-radius:100%;
    position:absolute;
    left:-25px;
    top:-25px;
}
.dot2 {
    background-color:white;
    width:50px;
    height:50px;
    border-radius:100%;
    position:absolute;
    right:-25px;
    top:-25px;
}
.dot3 {
 background-color:white;
    width:50px;
    height:50px;
    border-radius:100%;
    position:absolute;
    right:-25px;
    bottom:-25px;
}

.dot4 {
 background-color:white;
    width:50px;
    height:50px;
    border-radius:100%;
    position:absolute;
    left:-25px;
    bottom:-25px;
}

Demo: http://jsfiddle.net/ofejxfj6/

You can tweak it a little (size of circles/dots and dimensions), but it is pretty close, IMHO.