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CSS CSS Layout Techniques Display Modes Inline-Block Formatting

Mark Lawson
Mark Lawson
6,148 Points


Around 1:30 into the video, he adds a margin-top: 15px to the code; however, it does not move anything. I have to add quite a lot of margin-top to the CSS, this then forces both the logo and the main-nav to shift down. My question is; does the top-margin actually work in this situation??

.main-nav li { margin-top: 15px; margin-right: 10px; }


1 Answer

Steven Parker
Steven Parker
230,274 Points

:point_right: This is called margin collapse. When there's nothing intervening (like a border or padding) the vertical margins of a parent and child element are combined, and only the larger one takes effect. The same thing happens between an element and its siblings when they are stacked vertically.

Unordered lists have vertical margins by default, so you won't see any change until you set a margin on the child LI that is larger than the default of the UL.

And no, it doesn't look like the margin set on the LI's in the video is large enough to do anything!