HTML CSS

Cascading Style Sheets (CSS for short) is a network standard for influencing the display of HTML documents: http://www.w3.org/Style/CSS/.

By default, makeinfo includes a few simple CSS commands to better implement the appearance of some of the environments. Here is a couple of them:

     pre.display { font-family:inherit }
     pre.smalldisplay { font-family:inherit; font-size:smaller }
     

A full explanation of CSS is (far) beyond this manual; please see the references above. In brief, however, this specification tells the web browser to use a `smaller' font size for @smalldisplay text, and to use the `inherited' font (generally a regular roman typeface) for both @smalldisplay and @display. By default, the HTML <pre> command uses a monospaced font.

You can influence the CSS in the HTML output with the --css-include=file option to makeinfo. This includes the contents file in the HTML output, as you might expect. However, the details are somewhat tricky, to provide maximum flexibility.

The CSS file may begin with so-called @import directives, which link to external CSS specifications for browsers to use when interpreting the document. Again, a full description is beyond our scope here, but we'll describe how they work syntactically, so we can explain how makeinfo handles them.

There can be more than one @import, but they have to come first in the file, with only whitespace and comments interspersed, no normal definitions. (Technical exception: an @charset directive may precede the @import's. This does not alter makeinfo's behavior.) Comments in CSS files are delimited by /* ... */, as in C. An @import directive must be in one of these two forms:

     @import url(http://example.org/foo.css);
     @import "http://example.net/bar.css";
     

As far as makeinfo is concerned, the crucial characters are the @ at the beginning and the semicolon terminating the directive. CSS provides for a number of different @-directives, and makeinfo treats them all the same way. When reading the CSS file, it simply copies any such @-directive into the output, as follows:

• If file contains only normal CSS declarations, it is included after makeinfo's default CSS, thus overriding it.
• If file begins with @import specifications (see below), then the import's are included first (they have to come first, according to the standard), and then makeinfo's default CSS is included. If you need to override makeinfo's defaults from an @import, you can do so with the ! important CSS construct, as in:

            pre.smallexample { font-size: inherit ! important }
            

• If file contains both @import and inline CSS specifications, the @import's are included first, then makeinfo's defaults, and lastly the inline CSS from file.

If the CSS file is malformed or erroneous, makeinfo's output is unspecified. makeinfo does not try to interpret the meaning of the CSS file in any way; it just looks for the special @ and ; characters and blindly copies the text into the output. Comments in the CSS file may or may not be included in the output.