Detailed answer
Use details with a summary that explains what will be revealed.
Remaining content expands and collapses through native behavior. It suits supplemental details, but burying every essential instruction in many closed sections can make a guide hard to use. Test keyboard operation and keep the summary meaningful on its own.
Example
<details><summary>Why does an image need alt text?</summary><p>It provides a text equivalent for meaningful visual information.</p></details>
Understanding the behavior
Details and summary provide a native disclosure with built-in open and closed behavior. The summary should describe the hidden content rather than use a vague label such as More. Essential task instructions should remain easy to discover.
Practical implementation notes
Activate the summary with a keyboard and inspect the open state. If content must always be visible for printing or a particular task, account for that requirement rather than assuming a closed disclosure is sufficient.
How to check it
Activate summary using the keyboard and inspect whether the extra content opens and closes.
Expected result
The native disclosure toggles while the summary remains identifiable.
Watch out: Avoid redundant handlers that duplicate native toggling.
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