Here is a simple example of CSS code that you can add to your Nicepage project 
to create a parallax effect for a header image on mobile devices:






/* Add the following CSS to your Nicepage Site Settings */

/* Ensure the body has full height */
html, body {
    height: 100%;
    margin: 0;
    overflow-x: hidden;
}

.parallax-header {
    /* Set a specific height for your header */
    height: 300px;
    background-image: url('path-to-your-image.jpg'); /* Replace with your image URL */
    background-attachment: fixed;
    background-size: cover;
    background-position: center;
}

@media screen and (max-width: 768px) {
    .parallax-header {
        /* For mobile devices, keep the background fixed */
        background-attachment: fixed;
    }
}



HTML and Body Full Height: Ensures the body has full height and no horizontal overflow.
.parallax-header: This is the class for your header section.
background-image: Specify the path to your background image.
background-attachment: fixed: This creates the parallax effect by fixing the background image.
background-size: cover: Ensures the image covers the entire section.
background-position: center: Centers the background image.
Media Query: Targets devices with a width of 768px or smaller (you can adjust this as needed).


You can try the following code. I don't know exactly how it will work in your case, but I think it's worth a try.