Observation Details
FAQ section cannot be reached by keyboard navigation as the interactive elements are custom built and do not use correct semantic HTML.
Remediation Notes
Ensure, using correct semantic HTML elements for all interactive elements. In case of accordions, these could be <detail> and <summary> constructs or ones with <button> as the accordion item "header".
Keyboard navigation is a must.
For custom building an accessible accordion component, please refer to BFIT-Bund Handreichung "Accessible design of user interface elements – Accordion".