Editing Browser engine (section)

==Layout and rendering==

The [[layout (computing)|layout]] of a [[web page]] is typically specified by [[CSS|Cascading Style Sheets]] (CSS). Each style sheet is a series of rules for how the page should be presented. For example, some rules specify [[Web typography|typography]] details, such as [[font]], color, and text size, while others determine the placement of images. The engine combines all relevant CSS rules to calculate precise graphical coordinates for the visual representation it will paint on the screen.<ref name=behindscene/><ref name="howBlinkWorks"/>

Some engines may begin rendering before a page's resources are downloaded. This can result in visual changes as more data is received, such as images being gradually filled in or a [[flash of unstyled content]].<ref>{{Cite web |first=Ryan |last=Boudreaux |date=October 18, 2013|title=How to prevent Flash of Unstyled Content on your websites |url=https://www.techrepublic.com/blog/web-designer/how-to-prevent-flash-of-unstyled-content-on-your-websites/ |access-date=2021-10-09 |website=TechRepublic |language=en |archive-date=2021-03-05 |archive-url=https://web.archive.org/web/20210305133101/https://www.techrepublic.com/blog/web-designer/how-to-prevent-flash-of-unstyled-content-on-your-websites/ |url-status=live }}</ref>