CSS Blur on Background Image While Preserving Content Clarity

In an attempt to blur a background image in a CSS setting, it's common to encounter the issue where the content (text or other elements) also becomes blurred. This is where the concept of z-index and pseudo elements come into play.

To blur the background image without affecting the content, the following approach can be employed:

1. Creating a Container for the Background: Enclose the background image within a div or other container and assign it a class, such as "blur-bgimage."
2. Introducing a Pseudo Element: Within the "blur-bgimage" class, add a pseudo class like :before. This creates a layer behind the container that inherits the background image.
3. Blurring the Background: Apply the blur effect to the pseudo element using CSS filters. This will blur the inherited background image without impacting the content.
4. Overlaying the Content: Place the content within the "blur-bgimage" container, ensuring it has a higher z-index (e.g., z-index: 1) than the blurred background (z-index: 0).

Below is an example code:

.blur-bgimage {
    overflow: hidden;
    margin: 0;
    text-align: left;
}
.blur-bgimage:before {
    content: "";
    position: absolute;
    width: 100%;
    height: 100%;
    background: inherit;
    z-index: -1;

    filter: blur(10px);
    -moz-filter: blur(10px);
    -webkit-filter: blur(10px);
    -o-filter: blur(10px);

    transition: all 2s linear;
    -moz-transition: all 2s linear;
    -webkit-transition: all 2s linear;
    -o-transition: all 2s linear;
}

By implementing this approach, you can effectively blur the background image while preserving the clarity of your content, allowing for visually appealing website designs.