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Unexpected Margin Collapse in CSS with Nested Flex Containers in Bootstrap 5

πŸ‘€ Views: 81 πŸ’¬ Answers: 1 πŸ“… Created: 2025-08-24
css bootstrap-5 flexbox HTML

I'm getting frustrated with I'm trying to implement I'm getting frustrated with I'm experiencing an issue where margins seem to be collapsing unexpectedly when using nested flex containers in my Bootstrap 5 project... I have a main container set up as a flexbox, and inside it, I have child elements that are also flex containers. However, the margins on the child elements are merging with the margins of their parent container, leading to layout inconsistencies. Here’s a simplified version of my HTML structure: ```html <div class="d-flex flex-column"> <div class="flex-grow-1 p-3 bg-light">Parent 1</div> <div class="d-flex flex-column"> <div class="mb-3 p-3 bg-primary">Child 1</div> <div class="mb-3 p-3 bg-secondary">Child 2</div> </div> <div class="flex-grow-1 p-3 bg-light">Parent 2</div> </div> ``` In this example, I expected the margins on the child elements to create space between them and the parent flex container. Instead, there's no gap between the bottom of 'Child 2' and 'Parent 2', which is not what I intended. I’ve checked that the `overflow` property is not set to hidden or scroll, and I’ve tried adding `overflow: auto;` to the parent flex container, but the issue persists. I also tried using padding instead of margin on the child elements, but that doesn't solve the spacing issue between 'Child 2' and 'Parent 2'. I suspect it might be related to the way flexbox handles margin collapsing, but I could use some guidance on best practices to prevent this behavior in a nested flex context. Any insights would be greatly appreciated! I'm developing on Ubuntu 22.04 with Html. Thanks for any help you can provide! Any pointers in the right direction? Thanks for taking the time to read this! I'm working on a mobile app that needs to handle this. I'd be grateful for any help.