Add Sass color accessibility theme function

[guylepage3]

Description Add Sass function that auto detects background color and outputs the correct "light" or "dark" color theme based upon color accessibility standards.

Tweet - https://twitter.com/guylepage3/status/1075021874990604290

Looking for a #sass function that auto detects background color and outputs the correct "light" or "dark" color theme based upon color accessibility standards. @UniverseLabs #meta

Tasks

• [x] Create sass function
• [x] Test

[guylepage3]

Need to test out something like...

// Color contrast
@function color-yiq($color) {
  $r: red($color);
  $g: green($color);
  $b: blue($color);

  $yiq: (($r * 299) + ($g * 587) + ($b * 114)) / 1000;

  @if ($yiq >= $yiq-contrasted-threshold) {
    @return $yiq-text-dark;
  } @else {
    @return $yiq-text-light;
  }
}

[guylepage3]

Done. Included in 1.5