Why is My Top Margin Ignored After a Floated Element in CSS?

Top Margin Ignored After Floated Element: Understanding the CSS Flow

Despite carefully defining a top margin for a div, you may encounter a scenario where the margin is ignored when the preceding div is floated. This behavior stems from the CSS specification, which states that floated elements are considered outside the normal flow. Consequently, non-positioned block elements created before or after a floated element behave as if the float didn't exist.

Example Code

Consider the following HTML code:

<div>

In this example, the second div has a margin-top of 90px. However, in Firefox and IE8, the second div appears to be touching the first div, without the noticeable top margin.

Solution: Creating a Wrapper

To resolve this issue, a simple and effective solution is to wrap the second div within another div:

<div>

In this revised code, the wrapper div's padding-top property defines the space between the wrapper and its content. Importantly, this padding is applied internally, meaning it doesn't affect any external elements, such as the floated div. As a result, the second div is now properly separated from the floated div, despite the floated div's interference in the normal flow.

Conclusion

Grasping the CSS flow and the impact of floated elements is crucial in layout design. By understanding these concepts and employing the appropriate solutions, such as wrapping elements with internal padding, you can ensure that your web pages display as intended, even when floated elements are present.

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