Full background image not showing up on desktop

Okay so I know that this is probably a dumb question and I'm missing an easy simple fix.  But I've been google searching, double checking my code, and racking my brain and not fixing this simple issue. I appreciate any help given. Even if it is just a link with a good reading resource that will help me solve my own issue (believe it or not I have been googling for an answer before asking but maybe I'm asking the wrong questions). The MDB Pro version I am using is 4.4.1 (according to the read me file but the download link in my account say 4.4.3)

1.  When I use your provided sample background image with the url link the your background image shows up fine.
2. I commented out your background image in the css
3. I added a background image to the img folder
4. I added the path of the image in the img folder to the css
5. I refreshed the page and it does not work
6. I tried both paths to see if one would work over the other and neither did
   1. background: url("https://mdbcdn.b-cdn.net/img/green-sea-turtle.jpg")no-repeat center center fixed;
   2. background: url("img/green-sea-turtle.jpg")no-repeat center center fixed;

  Here is my css code:

Start your code here

/* YOUR CUSTOM STYLES */ html, body, header, #intro { height: 100%; } #intro { /*background: url("https://mdbcdn.b-cdn.net/img/Photos/Horizontal/Nature/full%20page/img%20%283%29.jpg")no-repeat center center fixed;*/ background: url("https://mdbcdn.b-cdn.net/img/green-sea-turtle.jpg")no-repeat center center fixed; -webkit-background-size: cover; -moz-background-size: cover; -o-background-size: cover; background-size: cover; } .top-nav-collapse { background-color: #24355C; }

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