← All elements
<div class="na"><details open><summary>Frontend</summary><details><summary>HTML</summary><p>Structure and meaning.</p></details><details><summary>CSS</summary><p>Layout, motion and theme.</p></details></details><details><summary>Backend</summary><p>Servers, data and APIs.</p></details></div>About this accordion
A two-level accordion made from details elements inside details, with a rotating chevron on each level. Open an example, copy the HTML and the CSS, and paste them into your page. There is nothing to install and no JavaScript to load.