I’m encountering an issue with CSS where a child element’s negative margin is ignored due to collapsing margins when the parent element has zero padding. Adding even a minimal padding to the parent (e.g., 0.03px) resolves the issue, but this feels like a hack. I would like to understand why this happens and if there is a more appropriate solution.

Here’s a simplified example of the issue with inline styles:

<br>
<br>
<br>
<div style="padding-top: 0; background-color: red;">
  <div style="margin-top: -5px;">Child Content</div>
</div>

<br>
<br>
<br>
<div style="padding-top: 0.03px; background-color: red;">
  <div style="margin-top: -5px;">Child Content</div>
</div>

I have read about margin collapsing, but I’m looking for a confirmation on that please.

Any insights or solutions would be greatly appreciated!