// Replace `$search` with `$replace` in `$string`
@function str-replace($string, $search, $replace: "") {
  $index: str-index($string, $search);

  @if $index {
    @return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
  }

  @return $string;
}

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

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

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

// Retrieve color Sass maps
@function theme-color($key: "primary") {
  @return map-get($theme-colors, $key);
}

// Request a theme color level
@function theme-color-level($color-name: "primary", $level: 0) {
  $color: theme-color($color-name);
  $color-base: if($level > 0, black, white);
  $level: abs($level);

  @return mix($color-base, $color, $level * $theme-color-interval);
}

@function gradient-mask($color, $alpha) {
  $mask: rgba($color, $alpha);
  @return linear-gradient($mask, $mask);
}