W3C CSS2 Cascading Style Sheets, level 2 - instructional media + ...

User agents may treat ’fixed’ as ’scroll’. However, it is recommended they
interpret ’fixed’ correctly, at least for the HTML and BODY elements, since there
is no way for an author to provide an image only for those browsers that support
’fixed’. See the section on conformance [p. 32] for details.
’background-position’
Value: [ [ | ]{1,2} | [ [top | center | bottom] ||
[left | center | right] ] ] | inherit
Initial: 0% 0%
Applies to: block-level and replaced elements
Inherited: no
Percentages: refer to the size of the box itself
Media: visual
If a background image has been specified, this property specifies its initial
position. Values have the following meanings:
With a value pair of ’0% 0%’, the upper left corner of the image is aligned
with the upper left corner of the box’s padding edge [p. 82] . A value pair of
’100% 100%’ places the lower right corner of the image in the lower right
corner of padding area. With a value pair of ’14% 84%’, the point 14%
across and 84% down the image is to be placed at the point 14% across and
84% down the padding area.
With a value pair of ’2cm 2cm’, the upper left corner of the image is placed
2cm to the right and 2cm below the upper left corner of the padding area.
top left and left top
Same as ’0% 0%’.
top, top center, and center top
Same as ’50% 0%’.
right top and top right
Same as ’100% 0%’.
left, left center, and center left
Same as ’0% 50%’.
center and center center
Same as ’50% 50%’.
right, right center, and center right
Same as ’100% 50%’.
bottom left and left bottom
Same as ’0% 100%’.
bottom, bottom center, and center bottom
Same as ’50% 100%’.
bottom right and right bottom
Same as ’100% 100%’.
If only one percentage or length value is given, it sets the horizontal position
only, the vertical position will be 50%. If two values are given, the horizontal position
comes first. Combinations of length and percentage values are allowed,
(e.g., ’50% 2cm’). Negative positions are allowed. Keywords cannot be combined
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