responsive-full-background-image.css

body {
  /* Location of the image */
  background-image: url(img/ouisharelanding_bg.jpg);
  
  /* Image is centered vertically and horizontally at all times */
  background-position: center center;
  
  /* Image doesn't repeat */
  background-repeat: no-repeat;
  
  /* Makes the image fixed in the viewport so that it doesn't move when 
     the content height is greater than the image height */
  background-attachment: fixed;
  
  /* This is what makes the background image rescale based on its container's size */
  background-size: cover;
  
  /* Pick a solid background color that will be displayed while the background image is loading */
  background-color:#464646;
  
  /* SHORTHAND CSS NOTATION
   * background: url(background-photo.jpg) center center cover no-repeat fixed;
   */
}

/* For mobile devices */
@media only screen and (max-width: 767px) {
  body {
    /* The file size of this background image is 93% smaller
     * to improve page load speed on mobile internet connections */
    background-image: url(img/ouisharelanding_bg_mobile.jpg);
  }
	}