/// Get a breakpoint from a map.
///
/// @group 02-breakpoint
///
/// @param {String} $breakpoint - The breakpoint key.
/// @param {Map} $map [$breakpoints] - The map containing the breakpoint.
/// @return {Number} - The breakpoint value.
@function breakpoint($breakpoint, $map: $breakpoints) {
  @if not $map {
    @error 'Value passed for $map not found!';
  }
  @if not map-get($map, $breakpoint) {
    @error 'No breakpoint `#{inspect($breakpoint)}` found!';
  }

  @return map-get($map, $breakpoint);
}