The section defines a binding set. This is a GTK extension to CSS.
The section defines a color. This is a GTK extension to CSS.
The section defines the declaration of a CSS variable.
The section describes a complete document. This section time is the only one where gtk_css_section_get_parent() might return %NULL.
The section defines an import rule.
The section defines keyframes. See CSS Animations for details. Since 3.6
The section defines a CSS ruleset.
The section defines a CSS selector.
The section defines the value of a CSS declaration.
The different types of sections indicate parts of a CSS document as parsed by GTK’s CSS parser. They are oriented towards the CSS Grammar, but may contain extensions.
More types might be added in the future as the parser incorporates more features.