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CSS

            
              a {
  display: inline-block;
  position: relative;
}

a.on {
    text-indent: -999em;
}

a.on:after {
  bottom: 0;
  content: "Hide";
  left: 0;
  position: absolute;
  right: 0;
  text-indent: 0;
  top: 0;
}
            
          
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