Page content
While the modal is open, background content is made inert (if the browser supports it) and un-focusable. Try tabbing around after opening the modal.
This demonstrates a modal dialog that is closed by default. The button labeled "Open Modal" has the required trigger class.
While the modal is open, background content is made inert (if the browser supports it) and un-focusable. Try tabbing around after opening the modal.