How does `overflow: auto` magically clear floats and resolve height issues?

Overflow: Auto Magic: Clearing Floats and Resolving Height Issues

Your dilemma stems from the default behavior of floated elements, which are removed from the standard layout flow, causing the containing element's height to behave abnormally.

Why Overflow: Auto Stretches Wrappers

Overflow: auto doesn't directly clear floats; instead, it establishes a new block formatting context (BFC) for the wrapper element. This BFC has the following effects:

• Prevents floating children from escaping the wrapper.
• Forces the wrapper to establish a height to contain its floats.

This containment allows the wrapper to expand and fit around the floated columns, resolving the height issue.

Why Do You Need Clear Floats?

Floated elements are only exempt from the normal flow within their parent element. If you want to move content below a float to its own line, you need an additional element, known as a "clear" element. This element has the explicit purpose of clearing the residual space after the float and starting a new line.

In your example, overflow: auto establishes a BFC, effectively containing the floats. However, if you have other elements after the floats, they might not flow correctly without an explicit clear element.

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