CodePen Embed - CSS Custom properties example

<div class="one"></div>
<div class="two"></div>
<div class="one again"></div>
<div class="three"></div>

body{
  display:flex;
}
/*Global*/
:root{
  --div-color:red;
}
div{
  width:40px;
  height:40px;
  margin:20px;
  /*Usage*/
  background-color:var(--div-color);
}
.one{
  /*Local Override*/
  --div-color:green;
}

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