Add $contrast as third parameter of contrast-color() function.

[imkremen]

Add $contrast as third parameter of contrast-color() function.
If both colors meet the contrast requirements, $color1 will be used.

Example:

  $color: #6170c2;
  background-color: $color;
  color: contrast-color($color, white, black, 4.5); 
  // contrast($color, white) => 4.56;
  // contrast($color, black) => 4.6

Result CSS:

  background-color: #6170c2;
  color: white; 

[xi]

See #4 (comment)