HTML (HyperText Markup Language) is the standard markup language used to create web pages. It provides the structure and content of websites by using a system of tags and elements.
CSS (Cascading Style Sheets) is used to style and layout web pages — to add effects such as colors, fonts, and spacing. It works alongside HTML to create the visual presentation of web content.
JavaScript is a programming language that enables interactive web pages. It can update content, control multimedia, animate images, and perform many other dynamic functions on websites.
To create an accessible expand/collapse widget, you should:
<details> and <summary>Yes, the native HTML <details> element is fully accessible by default. It has built-in keyboard support, proper focus management, and works with screen readers without requiring additional ARIA attributes.
The native <details> element is supported in all modern browsers including:
For older browsers, polyfills are available.