Opus stores choices, never style. "Framed", "Tinted", "Primary" set a class, and the template decides what it looks like. Opus therefore works with any template, and makes the most of the one it finds.
Under Corpus
Opus borrows the grid, the classes and the design of the Corpus template directly: its column ratios, its section backgrounds, its cards, its alerts, its buttons, its icon sheet, its image viewer, and its customisable hue.
- The visitor downloads only one extra stylesheet, and no script of Opus's own.
- Change the colours once in Corpus: every Opus layout follows, dark mode included, without touching anything.
Under Cassiopeia and other templates
When Corpus is not there, Opus loads a fallback stylesheet and a small script. The stylesheet reads the site's values (Bootstrap colours, corner radii, spacing) rather than imposing its own. Opus then brings what Corpus would have provided: its own icon sheet, its image viewer for the gallery, its card, alert and background classes.
The result follows your design: if Cassiopeia's colours change, the Opus layouts follow too.
What comes from Joomla
The carousel and the tabs use the scripts shipped with Joomla 6, with their keyboard support and ARIA roles. Nothing is loaded twice, and nothing depends on an outside library.
Changing template
Switching from Cassiopeia to Corpus, or the other way round, requires no change to the modules: the same choices give the same layout, dressed by the new template. Only the custom CSS rules that target classes of a specific template may need a review; the Classes produced panel points them out (chapter 7).
Up to date for Opus 1.5.