how can I controlled hight of section parallax

Hello, I am working with a section parallax (http://themes.semicolonweb.com/html/canvas/index-parallax.php / Title: Embedded Videos).

This sections height is not usefull for me. How can I controlled it's hight? (if possible for mobile devices too)

I am using in iframe codes for youtube videos.

<div class="section parallax full-screen nomargin noborder" style="background-image: url('images/bannerhavuzu/<%= strBannerim %>');" data-stellar-background-ratio="0.7">
  <div class="vertical-middle">
    <div class="container clearfix">

      <div class="col_four_fifth divcenter nobottommargin">
        <iframe width="560" height="315" src="https://www.youtube.com/embed/7lTDkfZs_5s?rel=0&showinfo=0" frameborder="0" allowfullscreen></iframe>
      </div>

    </div>
  </div>
</div>

I realy try to fix this but I could not (data-height: xxx - height xxpx! important... not work :) ).

Thank you in advance.