@mixin img-style($param) {
  $size: $param * 16;

  width: $size;
  height: $size;

  &.is-rounded {
    border-radius: 50px;
  }
}
.nes-avatar {
  @include img-style(2px);

  &.is-small {
    @include img-style(1px);
  }
  &.is-medium {
    @include img-style(3px);
  }
  &.is-large {
    @include img-style(4px);
  }
}