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  button.button(style=`--hue: ${Math.random() * 360}`) Show me attention


  min-height 100vh
  display flex
  align-items center
  justify-content center
  cursor pointer
  padding 1rem 1.25rem
  color #fff
  font-weight bold
  font-size 1.25rem
  transition background .1s ease
  background 'hsl(%s, 100%, 50%)' % (var(--hue))
  outline-color 'hsl(%s, 100%, 80%)' % (var(--hue))
  animation flow 2s infinite ease-in-out
    background 'hsl(%s, 100%, 40%)' % (var(--hue))
    background 'hsl(%s, 100%, 30%)' % (var(--hue))
    position relative
    position absolute
    border-radius 100%
    bottom 0
    left 0
    right 0
    height 4px
    background hsl(0, 10%, 85%)
    animation shadow 2s infinite ease-in-out
    z-index -1

@keyframes shadow
  0%, 100%
    transform scaleX(1)
    opacity 1
    opacity .2
    transform scaleX(.25)
@keyframes flow
  0%, 100%
    transform translate(0, 0)
    transform translate(0, -25%)