Function createCourseReaderViewer

createCourseReaderViewer(
target: string | HTMLElement,
options: CourseReaderViewerOptions,
): CourseReaderViewer
Creates a responsive single-page or spread viewer.

The viewer renders every page through createCourseReaderPage and switches layouts as the supplied media queries match. Navigation moves by one page in single mode and two pages in spread mode.
Parameters
- target: string | HTMLElement
  Host element or selector that receives the viewer.
- options: CourseReaderViewerOptions
  Pages, presets, layouts and registry overrides.
Returns CourseReaderViewer
A handle for navigating and destroying the viewer.
Throws
When options.pages is empty or a page cannot be found.
Example
```
const viewer = createCourseReaderViewer("#reader", {
  pages: ["#page-1", "#page-2"],
  preset: "analog-gray-copy",
  layouts: [
    { query: "(min-width: 900px)", mode: "spread", gutter: "bound-volume" },
    { query: "all", mode: "single" },
  ],
});
```
- Defined in viewer.ts:158