Help:User style

The user can customize fonts, colors, positions of links in the margins, and many other things! This is done through custom Cascading Style Sheets stored in subpages of the user's "User" page.

E.g. To create your own CSS modifications for the skin you are presently using, create a page at containing the CSS you want to use (to apply your changes regardless which skin you are using, put them in instead). For how to hide particular messages, see WP:CSSHIDE.

For each user-definable style, a skin is first selected, and a corresponding Cascading Style Sheet (CSS). For each skin, the user can make various choices regarding fonts, colors, positions of links in the margin, etc. CSS is specified with reference to selectors [1]: HTML elements, classes and id's specified in the HTML code. Accordingly, what the possibilities are for each skin can be seen by looking at the HTML source code of a page, in particular looking at these classes and id's: the more there are, the more versatility there is.

Site-wide CSS is in

Enter some CSS into that page. Preview of CSS works in a special way: it allows viewing of the margins of the page (not the contents) on the basis of the style info in the page, provided that the skin used is the skin for which the page applies. This has limitations. E.g., one can preview how links in the margin will look, but these may not be of all the types one would want to check. After saving, while still on the page or while on any other page, do a forced reload (shift-reload/ctrl-f5) to get the new files.

To import CSS from a user subpage, use the importStylesheet command in your :

The HTML source of a page contains lines like

Thus the server provides HTML referring to the CSS and JS files, but it does not do any interpretation of their content. The interpretation is done by the browser, depending on its capabilities and settings.

Some computers, e.g. in internet cafes, mobile devices/tablets, do not allow users to set preferences for the browser. In that case the user subpages allow the setting of a user style anyway.

When the browser has been set to the option to ignore the font size specified in the webpage or external CSS, CSS lines regarding font size have to be put in the local CSS.

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Wikipedia