Bootstrap changebody background color (using color picker)

I'm trying to implement a color picker on certain spots of my site. A simple div no prob, but the color picker for the bootstrap background is a problem.

Original Css background:

    html , body {
  background-color: grey !important;
}

Color picker Perfect situation (inside of my template/hbs file):

<style>
    body , html  {
      {{bind-attr style=background2}} !important;
    }
</style>

Why isn't this code working?

{{bind-attr style=background2}} = return 'background-color:'+this.get('color');