Parallax Scrolling Effect

Hello folks, hope you all in a good mood.

Recently I was looking at my old project and I think I want to share it here, because it seems some sites still using it.
So let get cracking.

HTML

<div class="img1">
    <h1>Parallax Background</h1>
</div>
<section>
    <h2>Section One</h2>
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Iste excepturi ad provident dolorum quos sint consectetur nobis soluta facilis, voluptatum est deleniti nam molestiae tempore possimus recusandae enim necessitatibus quae. Voluptate repellat perspiciatis repudiandae cumque!</p>
</section>

<div class="img2">
    <h1>Image Two</h1>
</div>

<section>
    <h2>Section Two</h2>
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Iste excepturi ad provident dolorum quos sint
            consectetur nobis soluta facilis, voluptatum est deleniti nam molestiae tempore possimus recusandae enim
            necessitatibus quae. Voluptate repellat perspiciatis repudiandae cumque!</p>
</section>

<div class="img3">
    <h1>Image Three</h1>
</div>

<section>
    <h2>Section Three</h2>
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Iste excepturi ad provident dolorum quos sint
            consectetur nobis soluta facilis, voluptatum est deleniti nam molestiae tempore possimus recusandae enim
            necessitatibus quae. Voluptate repellat perspiciatis repudiandae cumque!</p>
</section>

<div class="img4">
    <h1>Image Four</h1>
</div>

On the code above, I create 4 div for 4 images background with section in between of div.
Nothing special.

CSS

@import url('https://fonts.googleapis.com/css2?family=Montserrat:ital,wght@0,400;1,700&display=swap');

* {
    padding: 0;
    margin: 0;
}

body, html {
    height: 100%;
    width: 100%;
    font-family: 'Monserrat', sans-serif;
    line-height: 1.8em;
    font-size: 1em;
}

.img1 {
    background-image: url(../images/image1.jpg);
    min-height: 100%;
}

.img2 {
    background-image: url(../images/image2.jpg);
    min-height: 400px;
}

.img3 {
    background-image: url(../images/image3.jpg);
    min-height: 400px;
}

.img4 {
    background-image: url(../images/image4.jpg);
    min-height: 400px;
}

/* Text */
h1 {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);

    background-color: rgba(0,0,0,0.4);
    padding: 25px 80px;
    color: #fff;
    font-size: bold;
    text-align: center;
    text-transform: uppercase;
    line-height: 1.25em;
}

section {
    padding: 4em;
    text-align: center;

    h2 {
        text-transform: uppercase;
        margin-bottom: 1em;
    }
}

As you can see, .img1, .img2, .img3,and .img4 now has different image. I put all the images in directory images.
The key of parallax effect are 5 properties.
They are position,background-position, background-size, background-repeat, and background-attachment. Now, lets add them to 4 image classes

CSS

.img1, .img2, .img3, .img4 {
    position: relative;

    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;

    background-attachment: scroll;
}

Well, background-attachment: scroll is the default value. In order to make the effect, lets set the background-attachment to fixed. But, I want this effect working at the min-width:420px. So at mobile view will be default.

So I have to put @media query on my CSS
CSS

@media (min-width: 420px) {
    .img1, .img2, .img3, .img4 { 
        background-attachment: fixed;
    }
}

The full code

Credits:
All Images from: https://www.pexels.com/