The background-color property specifies the background color of an element.
With CSS, a color is most often specified by:
The opacity property specifies the opacity/transparency of an element. It can take a value from 0.0 - 1.0. The lower value, the more transparent.
Note: When using the opacity property to add transparency to the background of an element, all of its child elements inherit the same transparency. This can make the text inside a fully transparent element hard to read.
The 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.
By default, the background-image property repeats an image both horizontally and vertically. Some images should be repeated only horizontally or vertically, or they will look strange.
To repeat an image vertically, set background-repeat: repeat-y;
To repeat an image horizontally, set background-repeat: repeat-x;
To not repeat an image, set background-repeat: no-repeat;
The background-position property is used to specify the position of the background image.