@mixin focus($color, $isInset: false) {
  outline: none;
  @if $isInset {
    box-shadow: inset 0 0 0 2px rgba(red($color), green($color), blue($color), .5);
  } @else {
    box-shadow: 0 0 0 2px rgba(red($color), green($color), blue($color), .5);
  }
}