Transparent hollow or cut out circle

css, css-shapes, svg, transparency

Solution

You can achieve a transparent cut out circle with 2 different techniques :

1.SVG

The following examples use an inline svg. The first snippet uses the mask element to cut out the transparent circle and the second hollow circle is made with a path element. The circle is made with 2 arc commands :

With the mask element :

body{background:url('https://farm9.staticflickr.com/8760/17195790401_ceeeafcddb_o.jpg');background-size:cover;}

<svg viewbox="0 0 100 50" width="100%">
  <defs>
    <mask id="mask" x="0" y="0" width="80" height="30">
      <rect x="5" y="5" width="90" height="40" fill="#fff"/>
      <circle cx="50" cy="25" r="15" />
    </mask>
  </defs>
  <rect x="0" y="0" width="100" height="50" mask="url(#mask)" fill-opacity="0.7"/>    
</svg>

With one path element :

body{background: url('https://farm9.staticflickr.com/8760/17195790401_ceeeafcddb_o.jpg');background-size:cover;}
svg{
  display:block;
  width:70%;
  height:auto;
  margin:0 auto;
}
path{
  transition:fill .5s;
  fill: rgba(227, 223, 210, .8);
}
path:hover{
  fill:pink;
}

<svg viewbox="-10 -1 30 12">
  <path d="M-10 -1 H30 V12 H-10z M 5 5 m -5, 0 a 5,5 0 1,0 10,0 a 5,5 0 1,0 -10,0z"/>
</svg>

The main advantages of using SVG in this case are :

- Shorter code

- You can easily use an image or gradient to fill the circle mask

- maintain the boundaries of the shape and trigger mouse envents only over the fill respecting the mask (hover the transparent cut out circle in the example)

2.CSS only using BOX-SHADOWS

Create a div with `overflow:hidden;` and a round pseudo element inside it with border-radius. Give it a huge box-shadow and no background :

div{
    position:relative;
    width:500px; height:200px;
    margin:0 auto;
    overflow:hidden;
}
div:after{
    content:'';
    position:absolute;
    left:175px; top:25px;
    border-radius:100%;
    width:150px; height:150px;
    box-shadow: 0px 0px 0px 2000px #E3DFD2;
}

body{background: url('https://farm9.staticflickr.com/8760/17195790401_ceeeafcddb_o.jpg');background-size:cover;}

<div></div>

Browser support for box-shadows is IE9+ see canIuse

The same approach would be to use border instead of box-shadows. It is interesting if you need to support browsers that don't support box-shadows like IE8. The technique is the same but you need to compensate with the top and left values to keep the circle in the center of the div :

body{
    background: url('https://farm9.staticflickr.com/8760/17195790401_ceeeafcddb_o.jpg');
    background-size:cover;
}
div{
    position:relative;
    width:500px; height:200px;
    margin:0 auto;
    overflow:hidden;
}
div:after{
    content:'';
    position:absolute;
    left:-325px; top:-475px;
    border-radius:100%;
    width:150px; height:150px;
    border:500px solid #E3DFD2;
}

<div></div>

Problem

Original source