<div>s are adding extra margin that I didn't specify - css

Here is a demonstration of the problem: http://jsfiddle.net/DerekL/jL69M/4/
I am trying to add a 3px margin to each block so that they separate apart from each other. Originally without the margin: ... all blocks will be stuck to each other, both horizontally and vertically, as expected. When I add in margin-bottom: 3px, the browser does add a 3px margin at the bottom, but it also seems to add another ~5px at the bottom. This is frustrating because I can't even select the spaces the browser generated.
So what exactly are those spaces? How can I get rid of them?

This is caused by the default line-height, which is set by the browser. By setting it to 0, every div will stack onto each other without extra spaces. Since the divs are set to be inline-blocks, they will behave like inline elements such as <img>. Line height will apply to lines, which will affect all inline elements, which is the blocks in this case.
#board{
line-height: 0px;
}
This will solve the problem.

Related

CSS Inline margin issue

Hopefully an easy one.
I am concentrating heavily on the CSS side of things in my project, but am having an issue with block vs inline elements, and I don't really want to move on as I know it's fundamental to learning CSS. So the misunderstanding...
I have a span element which is inline.
<span>Please Login With Your Details Below</span>
There is a margin-left of 40px on this span which shows
However if I shrink the viewport small enough it does this
Issue: So on the new line it doesn't keep the margin...
However if I change the span to display:block it does this
which is what I want.
However I read this on https://www.impressivewebs.com/difference-block-inline-css/ regarding inline elements
Will ignore top and bottom margin settings, but will apply left and
right margins, and any padding
So it may be that I have misread it totally, but from what I understand it should have applied the left margin. Can someone explain why it didn't?
Thanks
When the user agent decides that inline content cannot fit the containing block, it will split the inline content into multiple inline boxes in order to accommodate the wrapping required to properly display without overflowing the containing block (if possible).
So in your example, Please Login With Your Details Below would overflow the containing element when you shrink the viewport, and therefore gets broken into two inline boxes:
Please Login With Your Details and Below.
According to the W3C recommendation:
When an inline box is split, margins, borders, and padding have no visual effect where the split occurs (or at any split, when there are several).
They provide this specific example that demonstrates what you are encountering:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
<TITLE>Example of inline flow on several lines</TITLE>
<STYLE type="text/css">
EM {
padding: 2px;
margin: 1em;
border-width: medium;
border-style: dashed;
line-height: 2.4em;
}
</STYLE>
</HEAD>
<BODY>
<P>Several <EM>emphasized words</EM> appear here.</P>
</BODY>
</HTML>
The margin is inserted before "emphasized" and after "words".
The padding is inserted before, above, and below "emphasized" and after, above, and below "words". A dashed border is rendered on three sides in each case.
Your described behaviour is totally fine and correct.
However, the information is correct that left and right margins are applied to the inline element.
The information you did not had is, that actually inline elements left margin only indent the first line.
Think of it as an element meant to be in one single line, where this line can have horizontal margin. Having the text break in multiple line is a nice feature. But from the point of view of the margin property its still one a line.
You can use this property
text-align: justify;
text-align-last: justify;

Do vertical margins collapse reliably and consistently across all browsers?

I'm trying to understand the effect that margin has on two elements. I have the following HTML, see the dabblet:
<p>some text</p>
<pre>some code</pre>
I have the following CSS:
body { color: white; }
p { background: red; margin-bottom: 50px; padding: 20px; }
pre { background: purple; margin-top: 40px; padding: 20px; }
So I've given the paragraph tag a bottom margin of 50px, and I've given the pre tag a top margin 40px. I was expecting therefore to find 90px vertical distance between them, but only have 50px.
I understand that the margins are collapsing, and that if I want to fix this then I need to add display: inline-block to the pre tag. But that causes the width of the pre tag to collapse.
Again, I know that I can fix the width problem by adding width: 100% to my pre tag, but I've got padding on the pre tag (20px), so this causes my elements to be too wide. I know that I can use box-sizing to deal with that, but what an almightly pain in the crotch it is to have to mess about with width, display and box-sizing just to have the desired amount of vertical space between two elements. So I simply refuse to do any of that.
Instead, I've decided that I'm just going to add margin-top: 90px to my pre tag, which will guarantee that I've got the 90px space that I want.
My question is: Are there any browsers out there that don't collapse margins in the way the others do? Will I inadvertently end up with 140px space (90px from the top-margin of the pre tag + 50px from the bottom margin of the paragraph tag)? In other words, are margins collapsed reliably and consistently across all browsers, or is there a browser out there that does it's own thing?
It's hard to give a definitive answer to this question because it's very broad. "All browsers" is a lot of browsers. There could always be some fringe browsers you never heard of that handle this differently. It all depends on how the browser's CSS rendering engine was written.
That said, any browser that wants to be taken seriously will try to adhere the W3C specs, which have the following to say about margin collapsing:
In CSS, the adjoining margins of two or more boxes (which might or might not be siblings) can combine to form a single margin. Margins that combine this way are said to collapse, and the resulting combined margin is called a collapsed margin.
Adjoining vertical margins collapse, except:
Margins of the root element's box do not collapse.
If the top and bottom margins of an element with clearance are adjoining, its margins collapse with the adjoining margins of following siblings but that resulting margin does not collapse with the bottom margin of the parent block.
Horizontal margins never collapse.
Source: Box Model (w3.org)
I figured it'd be a nice addition to just put your code to the test in as many browsers as possible. I made a test page page of your html (slightly modified), with an absolutely positioned 50px high block that should fit right in between the collapsed margin, to make it easier to spot a difference:
http://files.litso.com/playground/margin.html
Then I ran this through browsershots.org to get screenshots of how browsers would display this piece of HTML:
http://browsershots.org/http://files.litso.com/playground/margin.html#
(I have no idea how long this will stay cached, but I guess you could always just run it again)
Interestingly, the positioning of the blue block is a few pixels off in a bunch of the screenshots. You can still tell the margins are collapsed correctly, but I do wonder what exactly the problem is with the positioning.
The only browsers that don't seem to collapse the margin correctly are Dillo 3.0.2 and Links 2.7 on Debian 6.0, neither of which seem to listen to padding or margin properties at all (nor to the absolute positioning for that matter). They would mess up your layout no matter what, and you shouldn't worry about it. People use browsers like these for a specific reason, and seeing your page exactly as you intended it to be seen is not one of them.
TL;DR: Yes, it's safe to say that all browsers collapse these elements reliably and consistently.

CSS margins add up or are combined?

Let's assume that we have the following code:
<div style="margin-bottom:100px;">test</div>
<div style="margin-top:100px;">test</div>
I noticed that sometimes it creates 100px of margin between elements and sometimes it's 200px (when we use certain settings that I'm not familiar with). I can't find any information about that in the specification. What does this depend on?
If we have h1 and p in a blank document then the margin of h1 will be combined with the margin of p. They will not add up. Whichever is larger will be used.
This is happening because your margins are allowed to collapse. Certain margins may overlap (mostly block elements) and form a combined margin defined by the larger of the two values defined in the computed element style rules - that's what is happening here. This section from the CSS Box Model document explains it in detail.
Edit: As a point of interest, you can get around this (ie. break the collapsible margins) without breaking things (much?)in a couple of ways
Making the elements width: 100%; display: inline-block
Putting a height: 0; width: 0; overflow: hidden block in between the elements and putting a dot or something in it.
I forked ashley's fiddle to demonstrate. There are probably other methods but these are a quick a dirty way to get around collapsible margins if you need to.

margin-top doesn't move unless value is high

Probably a very simple fix to this one, been looking at it for a little bit now and cant figure it out.. Here is my code:
margin-top:10px;
width:998px;
min-height:100px;
max-height:300px;
border:1px solid #CCC;
-moz-border-radius: 10px;
border-radius: 10px;
background-image:url(../images/default/page.png);
overflow:hidden;
When the margin-top is set at 10px the div doesn't move at all. If i set the margin-top to be 200px then the div doesn't move. However if i set it to say 500px then it moves down 500 as expected.
I have already tried removing the min & max heights for just a single set height however this doesn't sort the problem. Not that it should cause issues in the first place.
Can anyone see my mistake? I am sure my coding is relatively sound and don' really know how to research solving this issue.
Check the margin and float of other elements. I don't see any problems with the code you provided.
In CSS, adjacent vertical margins collapse, pending certain conditions.
So say you have 2 divs stack 1 on top of another. The top div has a margin bottom of 30px, and the bottom div has a margin top of 20px. In this situation, the margins 'collapse' into the highest value, the 30px margin bottom on the top div.
More info on this can be found here
In your situation, i'd look at the CSS of the surrounding elements to see if changing those values would do what you want.
I have managed to resolved this issue by placing the divs above this one within another container Div and applying a margin-bottom:10px to it.
Its not totally ideal because it takes a little longer to code and adds another div which i don't really want but suppose it will have to do for now until i have a little more time to read up on this issue fully.
Thanks to everyone for your help and potential solutions.

Div Height/Overflow issue

The problem I'm having is I have two divs at the top of my page, one contains a repeating blue background, the other contains a background image.
I have to set the height of both divs in order for them to expand vertically, the don't expand with the content. I have that form on the right hand side set to overflow. Which I believe is what's causing the problem.
I have tried not having the height css in the code, but it still won't expand vertically.
In order to get the backgrounds to even show up I have to manually set the height.
This is the page: http://www.repipespecialists.com/landing/google/repiping.html
This is the CSS code:
#top_container {
width:100%;
height:1040px;
background-image:url(../images/top_bg_repeat.jpg);
background-repeat:repeat-x;
background-color:#83b4e9;
}
#top_header {
width:1200px;
height:1040px;
background-image:url(../images/header_bg.jpg);
background-repeat:no-repeat;
background-color:#83b4e9;
margin: 0 auto;
}
I agree with WDan in that the issue you are having is due to your use of float: left and float: right on the left_content and right_content div elements.
When you use float on an element, you are basically removing it from the normal flow of the document. By default, elements will appear on the page in whatever order you specify in the markup. Using float (or things like position: absolute) will remove the element from this "order", or "document flow", such that the floated element will be ignored when placing other elements in their default position on the page.
Since the space used by these floated elements are ignored, the top_header div does not take the floated element's size into account when determining its own size. This is why your div is not automatically expanding.
Another alternative to float is to use display: inline-block. Here are some links you can read to learn more about the differences:
http://www.ternstyle.us/blog/float-vs-inline-block
http://www.onderhond.com/blog/work/inline-block-vs-float/
http://designshack.net/articles/css/whats-the-deal-with-display-inline-block/
http://robertnyman.com/2010/02/24/css-display-inline-block-why-it-rocks-and-why-it-sucks/
I think the problem is you use float in 'left_content' and 'right_content'
Use “overflow: hidden” in the wrapper div.

Resources