Product Landing Page help needed

Product Landing Page help needed
0

#1

the css for the overview div

/*OVERVIEW STYLING*/
            #parallax{
                width:100%;
                height:700px;
                background-attachment:fixed;
                background-repeat: no-repeat;
                background-position:center;
                background-size:cover;
            }
            #Overview{
              
                width:100%;
            }
            #Headline{
                background:url(iphonex.png);
                background-attachment:fixed;
                text-align:center;
                background-position: center;
                background-repeat: no-repeat;
               
                width:100%;
            height:700px;
            }

            #FaceID{top:20%;
            width:100%;
            height:700px;
            text-align:center;}
           
            #Display{width:100%;
            height:700px;
            text-align:center;}

            #Camera{width:100%;
            height:700px;
            text-align:center;}

            #OS{width:100%;
            height:700px;
            text-align:center;}
           

           /* END */

and here is the html

<div id = "Overview">
            <div id = "parallax" style = "background:url(Headline1.jpg);">ff</div>
            <div id = "parallax" style = "background:url(Headline2.jpg);">ff</div>
           <div id = "Headline">
               
                
               <h1>The Iphone X</h1>
               <h2>Marvellous design,breathtaking performance and most importantly,a device bringing the world closer than ever</h2>
          
           </div>
           <div id = "parallax" style = "background:url(faceID.jpg);"></div>
           <div id = "parallax" style = "background:url(FaceID2.jpg);"></div>
           <div id = "FaceID">
            <h1>Unlock your phone with just a look</h1>
            <h3>The revolutionary feature of the Iphone X,FaceID lets you unlock your phone by detecting your facial features. So no need to enter complex passwords,just look at your phone and "Access Granted"</h3>
        </div>
           <div id = "Display">
                <div id = "parallax" style = "background:url();"></div>
                <div id = "parallax" style = "background:url();"></div>
               <h1>A vivid display keeping you hooked</h1>
               <h3>A super OLED display covering up the device's anterior that's so vivid,so colorful that you would not like to take your eyes off our best display ever. But don't worry,our 'Digital Wellness' feature keeps your phone usage in check and lets you enjoy both,your life and your Iphone X.</h3>
           </div>
           <div id = "Camera">
                <div id = "parallax" style = "background:url();"></div>
                <div id = "parallax" style = "background:url();"></div>
               <h1>Cameras designed to perfection to capture every detail of your memories</h1>
               <h3>A dual 12MP rear camera along with a 7MP front camera that gives you crystal clear photos and selfies accompanied by dual tone LED flash. </h3>
           </div>
           <div id = "OS">
                <div id = "parallax" style = "background:url();"></div>
                <div id = "parallax" style = "background:url();"></div>
               <h1>The OS the world prefers, new and improved</h1>
               <h3>The Iphone X comes with iOS 11, which is packed with features you've never even imagined. Animoji,emojis that come alive,better map guidance,improved Control Panel design  and much more! There's alot to explore with iOS 11.</h3>
           </div>
           
        

       </div> 

the thing is the divs with the parallax id are not reflecting the parallax effect. Please help