Accordion

Printed sections that open in place. Each head ends in a small square key printed +; open, the key latches below the plate and reads −.

Click a head, or Tab to it and press Enter or Space. Opening one closes the others: they share a name.

• Native <details> and <summary>: each head is announced as a button that is expanded or collapsed, with no script at all.
• The shared name is the browser’s own exclusive accordion; with no name, several sections can be open.
• Keep links and keys out of the head: it is already a button. Put them in the body.
• The key is drawn, not announced; the open state is carried by the element itself. Reduced motion drops the slide and keeps the text.