strange issue/bug, html5 nav element effecting absolute positioning of another item - css

Ok got this strange issue where i have a absolute positioned div with inside a header. Then there's a nav tag with a margin and for some the absolute positioned div instead of sitting top left of header it positioned where the nav starts. So if the nav has 100px top margin the div starts 100px down.
But the strange thing is if I apply a border to the header the absolute positioned div acts as how i would expect.
I'm using html5 boilerplate styles, this i suppose could be the issue.
It's easier to explain if you view an example. The below links are stripped down version and have identical mark up apart from one where the header has a border and the other it doesn't.
Example with the problem:
http://bennyb.co.uk/test/no-border.html
Example with the issue fixed when the border is applied
http://bennyb.co.uk/test/border.html
Thanks
B
EDIT:
Ok thought this was actually just related to nav but seems it's the same if a div

Apply
overflow: hidden;
to the header.

Related

Strange container div behaviour

I'm asking this for learning purposes; there aren't any negative aspects on this behaviour, but I just wonder if this could have any negative consequences in the future.
So I have a container div: content_wrap, which has two other div's: side_bar and main_content. The container div is 980px width, and is used to center its contents using margin-left and margin-right.
It's doing this correctly, however, when I was debugging the page (in Firefox), I noticed that the browser renders the div as being 0x0px and renders the parent div off-screen. However, it does position the child divs correctly. See this JSFiddle for an example: http://jsfiddle.net/7fsXp/7/
I Googled this and most of the answers have something to do with floats and are solved by using clear:both, but I don't use any floats. I did notice that if I change the main_content div from position:absolute; to position:relative;, the content_wrap is displayed correctly. Or I can fix it by setting a height for content_wrap.
I don't actually need to be able to see the content_wrap, so there isn't really a problem, as it is doing its job in means of centering the child divs. I just wondered if it would be a bad practice to leave it like this? Is it a bad thing, or does it matter?
Try adding other elements to this HTML and enjoy the horror :D
There are actually many things in your code, that I wouldn't do. First of all, when an element is with position: absolute or position: fixed its layout is "ignored" by other elements or in other words cannot "push" any element and that is why your container is having 0 height. It's like they are ethereal (best explanation ever, I know).
You should check this article on positioning -- http://css-tricks.com/absolute-relative-fixed-positioining-how-do-they-differ/
The fact that they are in the place you expect them to be is that there are actually no other elements in the HTML and the absolute element is positioned relatively to the body and so is the fixed one (but that's what elements with position: fixed always do). Looks what happens when I add some other content to the parent div -- http://jsfiddle.net/7fsXp/13/
So long story short - you shouldn't form your layout with absolute or fixed elements if you can do it without them.
position: fixed and position: absolute take the elements out of the flow, so using either of these positions on all child divs will collapse the parent div entirely.
If you have content below a collapsed div, it will flow up and over/under that content like this.
You don't need to position the main_content div absolutely, but you'll need to change a few things to top align the sidebar and main_content.
DEMO
Since sidebar is fixed, it's using the document, not the container div as a reference for top, while main_content would use the body (unless you add position: relative to the container). Getting rid of the body's default padding/margin will fix the small alignment difference.
body {
padding: 0;
margin: 0;
}
#main_content {
//remove position: absolute;
margin-top:70px; //top: 70px won't work unless you specify position
}
It depends on what you are willing to do, but because the default position for div is position: static; changing the position: relative; will avoid the collapse of parent div.

CSS Outer Div Moves with Inner Div

i've created a CSS Desk example to help with my question.
I have an outer div, .mainPage and it has a child div, .content. When I set .content's top margin to any size, .mainPage moves with the content.
I don't want that to happen, I want .mainPage div to stay at the top above the header, and the content to start 160px down, which is below the header.
The header is fixed so that only the content moves, to give the really nice effect of the background.
If you change margin-top on the content element to padding-top, the background on .main Page will go below the header. Is that the effect you are going for?
Also, just to note, you don't have a position of relative, absolute or fixed set on .mainPage, so z-index won't work.

Navigation Links Suddenly Unclickable

I'm working on a page for a class, just to display things (you can see them sorted by chapter in the body) but I originally had a list on the left that I used initially that just listed them all, and I wanted to keep it.
Problem is, once I started adding more CSS - I don't know where exactly - the area on the left just became completely unclickable. You can't highlight the text, you can't click any of it - nothing. I have absolutely no idea whatsoever what is causing this.
link to the site here
here is a pastebin link showing everything I have.
thank you, i really appreciate any help.
The .content div overlaps entire body area, because of "position: absolute;"
Add z-index: 9999; to #menu in your CSS and it should be clickable.
Other way is to use "position: relative; float: left;" to both .content and #menu, but you have to be carefull with their widths. Their sum of widths (including padding and margin and border) should be less or equal to the container width. In your case it should be body tag (actually a don't see body tag in your html).
That's because your .content div is using position: absolute; so it's taken out of the page flow and overlapping your sidebar because it has no width set (block elements span the full width of your viewport unless you give it a fixed width) ... just add a negative z-index value to your .content div and it should work fine.
More on z-index

Min-height and absolute positioning

I'm developing a mobile website that integrates horizontal swiping. Unfortunately this has created a headache when trying to get the rest of my website layout to work.
http://jsfiddle.net/N7eWS/4/ - try resizing your browser window fairly small and you'll see the #footer (red) halfway down the content inside #wrapper (green). This appears to be todo with setting height:100% on most of the elements and then the absolute positioning applied to the horizontal swiping div (swipeview-masterpage-1).
I want it so that #wrapper expands to the height of the content, the #footer sits underneath #wrapper and is always off the bottom of the screen (you should have to scroll to see it).
Is there anyway I can make this work without touching (or perhaps making minor changes to) the swipeview divs? Any ideas would be appreciated!
One of the problems is the position: absolute on #swipeview-masterpage-1 and then another absolute on the parent. Parent absolute elements will not expand to the height of any absolutely positioned children (example).
You also have a random <span> in the mix, which is an inline element and will have a height of 0 anyway. Remove that to make things clearer.
Now to why your footer is appearing in a strange way. Your #wrapper will always be 100% of the parent height, your footer will always exist at 100px (header) + 100%. Disable the min-height property and you will see the wrapper collapse, and the footer sit at 100px. That's why the #wrapper content overlaps the footer.

Div moves below another div when window resized

When I resize the browser window my navigation bar div drops below the search box div.
How can I stop the nav bar moving and keep it in the same place? The footer behaves itself and its structured in the same way?
Here's a link...
http://www.signport.co.uk/test/asg_template3.html
Thanks!
This happens because your menu does not have a width specified. Whereas you footer behaves because it has a width specified( div with id footerleft)
I'm testing on Chrome now, removing the width:100% you have set on the navigation bar div (wrapper_menu_full class) seems to do the trick. This 100% refers to its size compared to the containing div (#mainmenu3).
If this still doesn't work on IE7, try setting both divs inside #mainmenu3 to display:inline, although now I'm testing on Chrome it doesn't seem to make any difference.
REPLACE YOUR CSS
#mainmenu3 {
height: 150px;
line-height: 20px;
list-style-type: none;
overflow: hidden;
width: 100%;
}
YOU WILL GET THE DESIRE OUTPUT
You're using floated elements on both divs (searchfilter and menu).
When you are using the floated elements, and the width of the last of the floated element exceed parent's width, it goes moves to the next line (belov).
Put this into your css to make it work as you want:
#mainmenu3{position:relative;}
#search4{position:absolute;top:0;left:0;}
.wrapper_menu{position:relative;top:0;left:310px;}

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