A small supplementary explanation does not always require a custom JavaScript component. Native details and summary elements can provide a simple disclosure, though the content still needs to suit the pattern.
<details>
<summary>Which measurements do I need?</summary>
<p>Measure the width and height of the intended area.</p>
</details>
This example contains an additional question. Do not casually hide essential information, such as the only total price or a fundamental prerequisite, inside a collapsed area.
Inspect actual operation
Open and close the disclosure using both keyboard and pointer. Its summary should explain what it contains. Repeated labels saying only “More” are not useful distinctions.
Inspect long summaries, increased text size and expanded content on a narrow screen. Styling must not conceal the native control or focus indicator. Avoid adding contradictory roles and redundant keyboard handlers to an already functional native element.
For a group that keeps only one item open, HTML supports a shared name attribute on the details elements. Check this behaviour in the browsers you support.
For placement, ask whether someone needs the information before the next decision or whether it is genuinely supplementary. That question matters more than visually shortening a long page.