$my-colors: (
  'default-blue': #0071ce,
  'blue': #064f8e,
  'yellow': #f79428,
  'light-blue': #1888c8,
  'green': #54a546,
  'red': #C82022,
  'pink': #b51e6d,
  'orange': #e54e26
);

$my-opacity: (
  'dark': 1,
  'light': 0.8
);

@function get-color($key: 'default-blue') {
  @return map-get($my-colors, $key);
}

@function get-color-alpha($name: 'default-blue', $opacity: 'dark') {
  $color: get-color($name);
  // Get the named opacity level, if it exists
  @if map-key-exists($my-opacity, $opacity) {
    $opacity: map-get($my-opacity, $opacity);
  }

  // Use rgba() to manipulate the color's alpha level
  @return rgba($color, $opacity);
}

li h3 {
            color: get-color-alpha('default-blue', 'light');
          }