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jqui / sass / _progress_bar.sass

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progress, .progress
  -webkit-appearance: none
  margin: 10px 0
  width: 500px
  +bg-x($button-bg)
  border: 1px solid silver
  background-position-y: -70px
  +rounded-border(3px)
  height: 12px
  div
    display: block
    +bg-x($button-bg)
    background-position-y: -44px
    max-width: 100%
    height: 100%
    +rounded-border-left(3px)

=spinner($size: 64px)
  height: $size
  width-min: $size
  background: url(unquote("#{$spinner}")) no-repeat center
  background-size: $size
  
.spinner, *[role="spinner"], *[role="progress-indeterminate"]
  +spinner(48px)