CSS Background Image
background-image property specifies an image to use as the background of an element.
By default, the image is repeated so it covers the entire element.
Set the background image for a page:
This example shows a bad combination of text and background image. The text is hardly readable:
Note: When using a background image, use an image that does not disturb the text.
The background image can also be set for specific elements, like the <p> element: