CodePen

HTML

            
              %blink
  Goodnight sweet prince
            
          
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CSS

            
              body
  background-image: url(http://i.imgur.com/y7jj2FM.gif)
  background-size: cover

*
  font-size: 150px
  font-family: 'Comic Sans MS', cursive
  font-weight: bold
  color: #f00
  text-align: center

blink
  animation: blink 0.5s linear infinite

@keyframes blink
  0%
    opacity: 1
  50%
    opacity: 1
  50.01%
    opacity: 0
  100%
    opacity: 0
            
          
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JS

            
              
            
          
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