An expand/collapse widget, also known as an accordion or collapsible section, is a user interface element that allows users to show or hide content. It typically consists of a trigger (like a heading) that, when clicked, reveals or conceals an associated content area.
They help to declutter interfaces by hiding less frequently accessed information, improve navigation by organizing content hierarchically, and enhance user experience by providing a more focused view.
This can be particularly useful for FAQs, long articles, or detailed product descriptions.
The core idea is to toggle a CSS class (like "expanded") on the parent container. This class then modifies the `max-height` and potentially other properties of the content area to show or hide it. JavaScript is used to handle the click event and apply/remove the class.