How Do HTML `` and `` Backgrounds Differ, and How Can I Use Multiple Backgrounds Effectively?

Applying a Background to and/or

When applying a background to the or elements, one might notice a discrepancy in behavior. With a background set on the element, it encompasses the entire page, while the element's background is constrained to the area where content is displayed.

Why the Discrepancy?

In standards mode, the and elements do not inherently fill the viewport's height. However, the element will adopt the element's background color if not explicitly defined. Subsequently, this inherited background becomes the canvas background, covering the entire viewport.

Superimposing Multiple Backgrounds

To achieve a superimposed background effect, combining two background properties in a single element (e.g., ) is recommended. Using the background-image and background-color properties, or the background shorthand property, allows for seamless merging.

For instance, to superimpose a transparent background image over a solid background color, use:

body {
    background: #ddd url(background.png) center top no-repeat;
}

Using Multiple Backgrounds

To combine multiple background images, consider the following methods:

CSS2:

Set different background images on both the and elements, ensuring the element's height and minimum height are set:

html {
    height: 100%;
    background: #ddd url(background1.png) repeat;
}

body {
    min-height: 100%;
    background: transparent url(background2.png) center top no-repeat;
}

CSS3:

Use the multiple background syntax in a single property:

body {
    background: url(background2.png) center top no-repeat, 
                #ddd url(background1.png) repeat;
}

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