Accessibility
Accordion Pattern
An accordion displays vertically stacked sections of content, each of which can either be visible or hidden. They can help limit the amount of scrolling on a page.
Behavior
There are two main parts of an accordion section:
- The header: which is used to control the display of the sections body
- The body: a container that holds any content associated to the section, which is either visible or hidden
Keyboard Interaction
- Content for Example header 1 
- Content for Example header 2 
- Content for Example header 3 
- Each section header is focusable
- Enterand- Space: when focused on a section header, should toggle the visibility of its body
- Recommended:- Upand- Downarrows: when focused on a section header should navigate to the next/previous header.
- This should not change the state of the section (if the section is hidden, it stays hidden).
 
Markup
The header should contain a <button /> element that:
- Has the header text within it
- Has aria-controlswith the value set to the id of the body container that it controls and is associated with
- When the content is hidden aria-expandedshould be set to"false"
- When the content is visible aria-expandedshould be set to"true"
- If the section cannot be closed set aria-disabled="true"along witharia-expanded="true"
ARIA Documentation: http://w3c.github.io/aria-practices/#accordion