How to Fix Collapsing Top and Bottom Margins? - css

Question

I'm new to CSS and I'm trying to understand how to fix the following line from not working for top and bottom margins. It works for side margins just fine, however:
.contents {
...
margin: 10px 10px 10px 10px;
}
Example: http://jsfiddle.net/LCTeU/
How do I fix this?
Edit:
I've also tried padding the container instead, and that just expands the container to maximum size (why?):
.container {
...
padding: 10px 10px 10px 10px;
}

Answer 1

Use overflow:auto on any of the elements that are involved with the collapse. For example:
article {
overflow:auto;
}
jsFiddle example

Answer 2

This answer is based off of the fiddle you provided.
I think your approach is incorrect in that your applying a margin to the article to space it within the parent div tag. It is better to use padding in this case, since your attempting to separate the content from its outside border. So apply:
article {
//display: block;
clear: both;
padding: 10px;
}
This will cause the article tags to increase in size, however the borders of the container div elements will now be touching. To create space between elements a margin is applied.
.rounded-box {
background-color: #959392;
border-radius: 15px;
margin: 10px 0px;
}
Working Example http://jsfiddle.net/LCTeU/4/
So just to recap, when you want to create space between two elements use margin. When you want to create space between an element and its border (or you want an element to be surrounded by whitespace) use padding.

Answer 3

I found a fix that does not require a padding, and does not require changing the overflow of the container element:
article:after {
content: "";
display: block;
overflow: auto;
}
The idea being that we add another element at the bottom that disrupts the collapsing margin, without affecting the height or padding.

Answer 4

As per the fix that Erik Rothoff suggested, which does not seem to work in Safari, first I tried the following:
article:after {
content: "";
display: inline-block;
overflow: auto;
}
This does work in Safari but takes up space which I could not get rid off, messing up the grid so much that I would need to change margins.
Then I decided to combine the two by doing the following:
article:after {
content: "";
display: block;
padding-top: 1px;
margin-top: -1px;
}
This works in Safari, has an acceptable height of 1px which is negated by the negative margin top.