SASS: functions
// FUNCTIONS
// Text Contrast
@function text-contrast($background)
@if lightness($background) < 50%
@return lighten($background, 70%)
@else
@return darken($background, 70%)
// Set Text Color
@function set-text-color($color)
@if lightness($color) > 50
@return #000
@else
@return #fff
//Convert pixels to ems
@function em($pixels, $context: $font-size)
@if (unitless($pixels))
$pixels: $pixels * 1px
@if (unitless($context))
$context: $context * 1px
@return $pixels / $context * 1em