css margin seems to refer to body instead of parent? - html

I have the following HTML structure:
<div class="slide active" id="sli-0-1">
<div class="mediaWrapper" id="musWrapper">
<div class="albumWrapper" id="albumWrap-1">
. . .
</div>
</div>
</div>
For the entire code please refer to this jsFiddle
Since I set the height of the child div to 90% in order to compensate for the total of 10% vertical margin, I expected the div to vertically centered within its parent div. As you can see, that is not the case.
I have no clue why - never had this sort of problem before and for some reason I cannot for the life of me figure out what might becausing this behavior. Tried using padding instead of margin with the same height - no changes. Tried to only set margin-top to 5% and height to 90 - no changes.
This might very well be caused by some stupid mistake of mine, in which case I apologize in advance. If not, I would appreciate if somebody cared to explain this to me.
Thank you.

It's because the percentage based margin-top value is relative to the width, not the height. You will notice this if you resize the window horizontally - see the margin change relative to the width?
Box Model - 8.3 Margin properties
The percentage is calculated with respect to the width of the generated box's containing block. Note that this is true for 'margin-top' and 'margin-bottom' as well. If the containing block's width depends on this element, then the resulting layout is undefined in CSS 2.1.
As a work-around, you could absolutely position the element and add top: 5% for vertical centering.
Updated Example
div.albumWrapper {
background: transparent;
border: 1px solid #a00000;
margin: 0 2%;
width: 96%;
height: 90%;
z-index: 20;
position: absolute;
top: 5%;
}

You center the div by adding this line to the css corresponding to the div you intend it to affect
#id{margin: 0 auto;}
That will center your div in window

Related

Simple way of using the full browser available width (CSS Responsive Design)

3 div.
body margin of 10px.
Picture on the bottom
I want the divs to equally have the same width, the same margins on the sides while also covering/using the whole browser's width whichever size it is (desktop, tablet, mobile)
Here's what I did by using pourcentage and what I believe:
" The full browser width is 100%
If the div's margin are 10px and the body's margin are 10px then
The div's width would be around 30%.
Let's try 30%.
It fits - blank space too.
Let's try 30.5%.
Blank space, it's not equal on the sides.
Let's put 32%.
etc. "
but often I get extra blank space on the right or one div to go down because it's actually too wide.
Is there a more simple way to do this? Properties?
Thank you.
Design:
Media queries:
Your issue stems from the fact that you are mixing relative units with absolute ones - pixels are an absolute unit as 10px is always 10px, but a percentage is relative to the screen width, so no matter how close you can get it to fitting the full width of the screen, as soon as you change the width of the screen all of the values are going to change.
You have (at least) two options here:
First, switch all your units to percentages, so that every measurement is relative to the width of the screen. In other words, if you use percentage based margins, you will know exactly how much space you can allocate to each thing.
Alternatively, if you really need the margins to be an absolute pixel width, use CSS calc:
This feature of CSS allows you to mix unit types easily, and let the browser do the math to figure it out.
For example:
width: calc(33.333% - 20px);
will style the div to take up one third of the screen width, minus the width of a 10px margin on the left and a 10px margin on the right.
If all three divs have this width, the total space taken up will equal to 100% of the screen, with the space for all of the margins accounted for.
(if you want the first and last divs to have no margin on the left and right respectively, just change the calculation to match!)
More Information About 'Calc'
Extra tip! Remember that white-space in your code will add spaces in between your elements, so if you style everything to fill exactly 100% width, these extra spaces may still cause your items to break if you have not dealt with this
I would say the best way to approach this is have container elements for each div, so a structure like this:
<div class="container-full">
<div class="container-third">
<div class="content">
Hello world
</div>
</div>
</div>
.container-full{
width: 100%;
}
.container-third{
width: 33.33%;
padding: 10px;
}
.content{
width: 100%;
}
Utilize padding, instead of margin. Make sure to use box-sizing: border-box
display:flex is already widely suported, so you can rely on that instead of floats.
if you don't use box-sizing:border-box; for all the elements - you could at least for the divs in question along with a 10px padding.
Here goes sass:
.container {
display:flex;
& > div{
flex:0 0 33.33%;
padding: 10px;
box-sizing: border-box;
}
}
or you could use a percentage margin between the divs.
.container div{
width:30%;
float:left;
margin-right:5%;
}
.container div:last-child{
margin-right:0;
}

Container div does not expand to fit child div (without floats)

My container div does not expand to fit its child div - which has a top: 20px value.
I don't even have floats and have used both overflow:hidden (cuts part of the child div) or overflow:auto (creates scrollbars).
See codepen example: Codepen
<div class="container">
<div id="model">fdsf</div>
</div>
Appreciate any solutions to this problem.
Remove top and position properties and use margin: 10px auto 0 auto;
#model {
background: yellow;
border: 1px solid orange;
width: 100px;
height: 100px;
margin: 10px auto 0 auto;
display: block;
}
Demo
1) In your example, the container is expanding to fit the child div correctly. The height of the child is 100px plus two times the border of 1px, in total 102px. Then, the height of the container is exactly 102px, as the developer tools in any browser can tell you.
Height of the contents totals 102px, thus the inner height of the container is 102px. This is by definition "expanding to fit the contents".
2) Now, you are setting position: relative for your child div. The following quote from Mozilla Developer Network should give a complete explanation to what is happening in your example.
Relative positioning:
This keyword lays out all elements as though the element were not
positioned, and then adjust the element's position, without changing
layout (and thus leaving a gap for the element where it would have
been had it not been positioned). The effect of position:relative on
table-*-group, table-row, table-column, table-cell, and table-caption
elements is undefined.
3)
Obviously, you can get rid of this effect by getting rid of relative positioning, and just using margin instead. Regarding your comment, no, top, right, bottom, and left should absolutely not work. They are meant to be used for a totally different thing, for what the quote above explains.

Section element shrinking due to overflow:auto?

I have 2 section in my HTML document see Here, now when i reduce the window size to about 820px the 2ns section shrinks , Why does that happen?
see screenshot below:
now the second section has overflow:auto, if I remove that, everything works fine, Link HERE
But what is really causing the issue, the section element is definitely a block element, so why is it not taking 100% width? Can anybody explain?
You should delete section element's margin-top: -1px; style or set .intro-lpoo element's style: overflow: auto. The reason what I thought is here: BFC
Your floating elements on the top section cause the issue. If you use clearfixes , you will not have any problems!Also use the following property for responsive images.
img{
max-width:100%;
height:auto;
}
Ok, let's think about it.
You have intro-lpoo section with height: 100% and 2 divs into it with float. And 1 of this divs have height: 0 because in that you place absolute positioned img. The reason why your why-coworking not shrinks from the very beginning is height: 100% of intro-lpoo. But when you make your browser resolution smaller - height: 100% of intro-lpoo getting smaller, and because your right div (which contain absolute positioned img) have height: 0 and your left div ( intro-wrpr ) have float: left thats why why-coworking shrinks and fills available space next to intro-wrpr.
I hope to able to explain

Why is setting the top-margin of this child element pushing its parent container down with it?

I have two divs:
<div id="headercontainer" data-type="background" data-speed="5">
<div id="headersubcontainer">
<h1>Simple and Cost Effective Web Solutions</h1>
</div>
</div>
<div id="teamcontainer" data-type="background" data-speed="5">
<div id="teamsubcontainer">
<h1>Developed by a dedicated team</h1>
</div>
</div>
both have 100% widths and heights of 800px. The first heading I have set a top-margin: of 160px. Instead of moving the header lower into its parent div, it moves the parent div down with it as you can see in this picture:
Here is my relevant css:
h1{
font-size: 48px;
font-family: $header-font-stack;
font-weight: 100;
width: 400px;
}
#headercontainer{
width: 100%;
height: 800px;
background-image: image-url("background.jpg");
background-position: center top;
background-repeat: no-repeat;
}
#headercontainer h1{
text-align: center;
margin: 0px auto;
margin-top: 160px;
color: #610B21;
}
Using a padding works obviously, but I would like to be more proper and use a margin. How can set a top margin and move the heading lower into the container without moving the container with it?
This is due to margin collapsing:
Top and bottom margins of blocks are sometimes combined (collapsed)
into a single margin whose size is the largest of the margins combined
into it, a behavior known as margin collapsing.
This is resulting in the parent element reverse-inheriting the child element top margin.
You can prevent this by adding before the child element
Demo Fiddle
....or applying any of the below to the parent:
float: left / right
position: absolute
display: inline-block
Adding display:inline-block; to the parent likely being the preference if it is set to have a width to 100%
Demo Fiddle
just use box-sizing: border-box; on the parent and set the padding there instead of margin-top. It will help you keep consistent spacing on all sides anyways
JSFIDDLE
Just add some top-padding to the parent element. even 1px and it will fix it.
I would actually argue that this answer is better:
https://stackoverflow.com/a/49075574/2387316
Yes, I know it's my own answer, but I think it's important that we don't add random bits of padding, change box-sizing for no reason, add spurious elements to the DOM, or change display/padding simply to fix a display issue. Those solutions all cause problems on their own: SEO is worse, unpredictable box-sizing behavior when trying to do something else, annoyance caused by positioning and display changes, etc. This solution is good for SEO, is scalable, and has no other tangible effect when trying to do other things with your elements.

why doesn't height: 100% and width: 100% work?

Frustration
I am frustrated of having to search the internet time and again to find a way to get a simple webpage to fill the whole screen on any device. I don't care about resolution, text size, whether the text comes inside the screen or not or anything else. I don't care about anything. I have one word to display and it should come in the middle of the screen, vertically and horizontally.
CSS is driving me nuts. And I don't get why this ain't simpler. And bootstrap. Well, thanks a lot guys you helped me a lot! But why the hell don't you have a class that would simply take up all the visible space on the screen?
I have tried a lot of variations and none of them work. I just can't get that word to the freaking center of the screen.
Some variation
The simplest one: http://jsfiddle.net/IcyFlame/ngVSd/
<div style="height: 100%; width: 100%; text-align: center; vertical-align: middle;">Word</div>
I don't know why this does not work. And I want an answer as to why this does not work. And more importantly, I would really love it if you would just tell me how to make it work. All the time, everywhere.
This is a really useful question: Setting height: 100% on my label element doesn't work
The person who gave the answer says that it is 100% of what. Really cool. And how do I solve the overall problem? Oh no, I just answered the question.
All the questions after that have been marked as duplicates. One of which is:
Height: 100% doesn't work! Why?
Although the question is totally different, well, the moderators simply believed that this was a duplicate and it was marked as one.
Note: I am catering to a lot of screen sizes. I don't want to write any kind of absolute pixel heights and widths anywhere in my final code.
Please help me with this issue
Reference: I want the word to come in the middle as it does on this gorgeours website:
http://debarghyadas.com/
Note that this just a reference. I don't want to have the background image. The whole header part of the webpage takes up the whole screen, that is what I want to achieve.
Everything is centered and beautiful. That is where I wanna go.
To get vertical alignment you have to have a second div inside the first 100% sized one.
Approx centering (fine for small amounts of text) is easy: http://jsfiddle.net/ngVSd/4
If you want proper centering you have to set the height and width of the central div explicitly then give it negative margins of 1/2 the width and height. You also have to remove the padding and margin from body.
Note that to vertically center the text in the inner div you also need to set its line-height to be the same as its height: http://jsfiddle.net/ngVSd/6/
html, body {
height: 100%;
margin: 0;
padding: 0;
}
#outerDiv {
height: 100%;
width: 100%;
background-color: red;
text-align: center;
}
#wordDiv {
position: absolute;
background-color: lightblue;
top: 50%;
left: 50%;
width: 100px;
height: 100px;
line-height: 100px;
margin: -50px -50px;
}
<div id="outerDiv">
<div id="wordDiv">Word</div>
</div>
To be honest, I don't really understand what vertical-align is doing.
So I can't really explain where your example fails.
But if you don't care about compatibility with IE7 and smaller, you may use the 'display: table' options:
<div style="display: table; width: 100%; height: 100%; text-align: center">
<div style="display: table-cell; vertical-align: middle;">Word</div>
</div>
Hope that helps.
You need to set width and height of the html and body (any any other parents) to 100% as well, since 100% means 100% of parent width/height, rather than 100% of the screen.
div parent has no height specified to calculate % .
You need to set height to body, and for % body needs too to calculate from parent's height: html.
<html> will use window's browser as reference to calculate %.
See this on W3C site.
Specifies a percentage height. The percentage is calculated with respect to the height of the generated box's containing block. If the height of the containing block is not specified explicitly (i.e., it depends on content height), and this element is not absolutely positioned, the value computes to 'auto'. A percentage height on the root element is relative to the initial containing block. Note: For absolutely positioned elements whose containing block is based on a block-level element, the percentage is calculated with respect to the height of the padding box of that element. This is a change from CSS1, where the percentage was always calculated with respect to the content box of the parent element.