Web Design in a Nutshell, 3rd Edition

Length measurements

It is also possible to specify the position of the origin image in units of length . When length units are provided, they are interpreted as the distance from the top-left corner of the padding area to the top-left corner of the image. Length values must be provided with the horizontal measurement first.

In this example, the top-left corner of the image will start 150 pixels from the left edge and 15 pixels from the top of the intro paragraph, as shown in Figure 20-8.

    p.intro { background-image: url(something.gif);background-position: 150px 15px;
              background-repeat: no-repeat;}

Figure 20-8. Positioning with length measurements

It is valid CSS to specify negative length measurements, thus pulling the image out of the visible background area of the element. Not all browsers currently support negative background image values, so be sure to test on your targeted browsers.