This code is working fine using Chrome, IE, Opera, but not using Safari. I don't know why. I tried to follow some threads but none of them help me to show the background image of this section. Now I'm thinking maybe there's appropriate code of background-images for Safari?
This is the thread that I'm following: Background image not showing in Safari But not working for me
<section id="video" class="parallax-section">
 <div class="overlay"></div>
<div class="container">
  <div class="row">
      <div class="col-md-offset-2 col-md-8 col-sm-12">
          <a class="popup-youtube" href="https://www.youtube.com/watch?v=kxloC1MKTpg"><i class="fa fa-play"></i></a>
          <h2 class="wow fadeInUp" data-wow-delay="0.5s">WATCH WORKOUT TUTORIAL</h2>
          <p class="wow fadeInUp" data-wow-delay="0.8s">Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet. Dolore magna aliquam erat volutpat.</p>
      </div>
  </div>
</div>
CSS:
  #video {
  background: url("images/sample.png") 50% 0 repeat-y fixed;
  -webkit-background-size: cover;
   background-size: cover;
   background-position: center center;
   position: relative;
   color: #999;
   -webkit-filter: grayscale(100%); 
   filter: grayscale(100%);
   }
   #video .overlay {
   background: rgba(03,03,03,0.6);
   width: 100%;
   height: 100%;
   position: absolute;
   top: 0;
   }