Are `background-position-x` and `background-position-y` Officially Part of the CSS Standard?

Unraveling the Mystery of background-position-x and background-position-y: A W3C CSS Exploration

The realm of CSS properties often sparks curiosity and uncertainty, particularly when certain attributes exhibit varying levels of support across browsers. Among these intriguing properties lie background-position-x and background-position-y, which have raised questions about their inclusion in the W3C CSS standard.

Background-position-x and -y: A Tale of Controversy

Background-position-x and background-position-y have sparked conversations due to their inconsistent support among browsers. Gecko (Firefox) and Presto (Opera) remain steadfast in their omission of these properties, while Webkit (Chrome, Safari) embraces their functionality. This disparity has left developers pondering their official status within the CSS standard.

Answering the Query: Official References and Insights

To illuminate this mystery, we consulted official references and delved into the intricate discussions surrounding these properties. Our findings reveal that the separation of background-position into -x and -y was proposed for CSS 3 but ultimately rejected. The reasoning behind this decision stems from the working group's perception that the use case lacked sufficient merit to warrant the introduction of new properties.

Addressing Concerns and Assessing WebKit's Implementation

The rejection also highlighted concerns regarding potential ambiguity in scenarios involving multiple background images and the manipulation of CSS through the CSS Object Model (CSSOM). It remains unclear how WebKit and Trident managed to implement these properties and mitigate these concerns.

No Change in Syntax: Stable Background-position for CSS

Recent updates from the CSS Working Group confirm that there will be no adjustments to the syntax of background-position or transform-origin. This decision likely aims to avoid further delays in the standardization process.

A Glimpse into the Future: CSS 4 and Beyond

While these properties may not have found their place in CSS 3, the possibility of their inclusion in CSS 4 remains open. A current discussion on the www-style mailing list sheds light on ongoing developments in this area.

Update: Level 4 Approval Secured

In a recent update, background-position-x/-y and background-repeat-x/-y have been formally approved for inclusion in CSS 4. This marks a significant milestone in the evolution of CSS, recognizing these properties as legitimate standard attributes for background manipulation.

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