How do borders affect size of inner divs? - html

I am trying to understand how borders affect the size and visualisation of an inner div. I have this problem in my application, where a border is displayed around fields with errors, and I can't seem to get the CSS right. (BTW, it's obvious that I don't quite "get" CSS just yet. I am working on it).
Consider this page:
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Booking Dojo Application</title>
<style type="text/css">
html, body {
height: 100%;
margin: 0;
padding: 0;
overflow: hidden;
}
#appContainer {
height: 50px;
width: 500px;
background-color: red;
}
#innerContainer {
height: 50px;
border-width: 5px;
border-style: solid;
/*width: 100%;*/
}
#ruler {
width: 500px;
background-color: blue;
height: 20px;
}
</style>
</head>
<body>
<div id="ruler"></div>
<div id="appContainer">
<div id="innerContainer">
<span>AHAH</span>
</div>
</div>
</body>
</html>
If I don't specify the width of the inner div, then its width is the same as the parent including the border.
But then, if I DO specify the inner div's width, something weird happen: Chrome puts the border "out", but... only to the right?!?
I am obviously missing something. So:
Why am I seeing what I am seeing?
What I would love to do, is know what the inner div's width should be specified as in order to get the same result as "without width"? (Other than going "99%" which seems to "work" in my app, but.... meh )

http://jsfiddle.net/X3gw6/1/
You need:
-webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
-moz-box-sizing: border-box; /* Firefox, other Gecko */
box-sizing: border-box;
More info:
http://css-tricks.com/box-sizing/
Basically, inner div height and width are bigger, because of borders... that caused problems...

By default border is added to the width. If you do not specify a width the default is to take all of the space it can and make it fit. So the inner width is 100%-borders.
When you specify a width you are by default specifying the inner width. 100% plus borders > 100%.
box-sizing:border-box; rule when added means you are specifying the width with borders. This is part of CSS3.
If widths are percentages but you need a fixed size border, box-sizing:border-box; rule makes it possible. http://www.w3schools.com/cssref/css3_pr_box-sizing.asp

It's because borders add to the elements height and width. So a width of 100% is 500px plus 5px left and 5px right border = 510px. You can see that width: 490px; makes the inner container inline with the other elements: http://jsfiddle.net/2wLQR/
box-sizing: border-box; will stop it from going out of line: http://jsfiddle.net/2wLQR/1/

Related

How to enable scrolling when adjusting height of browser on a flexbox

So i created a flexbox like as follow and coloured the border as shown:
and basically what I'm trying to do now is to only let the box flex width wise whenever i resize the browser window which is working by default:
However, what I want now is that I only want it to flex whenever the width of the browser window is adjusted but not when the height of the browser window is adjusted. If i adjust the browser height now, the flexbox responds as such:
Therefore what I want is, whenever the height of the browser is reduced, i want the flexbox height to remain unchanged and make it scrollable height wise hence the scrollbar at the side would show whenever the height is reduced. It's similar to the https://www.apple.com/ website where if we adjust the width of the browser, it flexes but height wise its utilizing the scrollbar.
How do i achieve this?
* {
padding: 0;
margin: 0;
box-sizing: border-box;
}
html, body {
height: 100%;
}
#outer {
border: 1px solid black;
height: 90%;
display: flex;
width: 90%;
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" href = "style.css">
<title>Document</title>
</head>
<body>
<div id = "outer">
</div>
</body>
</html>
Therefore what I want is, whenever the height of the browser is reduced, i want the flexbox height to remain unchanged and make it scrollable height wise hence the scrollbar at the side would show whenever the height is reduced.
Given this requirement, what I would do is
Remove the height: 90%; line in your CSS. This is causing your flexbox to take up 90% of the height of your browser window, even upon resizing.
Add flex-direction: column;
Add some content that takes up more height than your browser window. You mentioned www.apple.com, after all :-)
Watch the vertical scrollbar appear!
HTML:
<body>
<div id = "outer">
<p>Images and text and content, oh my!</p>
<p>Images and text and content, oh my!</p>
<p>Images and text and content, oh my!</p>
</div>
</body>
CSS:
* {
padding: 0;
margin: 0;
box-sizing: border-box;
}
html, body {
height: 100%;
}
#outer {
border: 1px solid black;
display: flex;
flex-direction: column;
width: 90%;
}
p {
font-size: x-large;
border: 1px solid blue;
padding: 300px; /* or other sufficiently large property:value */
}

Why does DIV not occupy entire width of screen on mobile Chrome when another DIV has 100% width?

Here is my HTML code.
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<meta name="viewport" content="width=device-width">
<style>
body {
margin: 0;
}
.a {
background: orange;
border: 2px solid black;
}
.b {
padding: 0 2em;
width: 100%;
background: lightblue;
border: 2px solid black;
}
</style>
</head>
<body>
<div class="a">Foo</div>
<div class="b">Bar</div>
</body>
</html>
Here is the output I see when I view the page with an Android mobile device with Chrome browser.
The issue here is that the orange div does not cover the whole width of the page.
My question is not how to fix it. I know how to fix it. If I remove width: 100% from .b, it fixes this issue.
My question is about why this issue occurs only with Chrome on a mobile device but not on any other browser or not on Chrome on Desktop?
The related question at Why does my navigation div not extend to the full width of the screen on mobile devices? does not answer my question because none of the answer there discusses the CSS or user agent rules that causes this issue. More importantly I am trying to understand why this issue occurs only on Chrome on a mobile device.
Your issue does indeed occur on Chrome on desktop, and is not restricted to just mobiles.
As for the cause of your problem, it's to do with the box model:
By default in the CSS box model, the width and height you assign to an element is applied only to the element's content box. If the element has any border or padding, this is then added to the width and height to arrive at the size of the box that's rendered on the screen. This means that when you set width and height you have to adjust the value you give to allow for any border or padding that may be added.
In order to ensure that your .b element is constrained within the width of the container is to apply box-sizing: border-box it, as is seen in the following:
body {
margin: 0;
}
.a {
background: orange;
border: 2px solid black;
}
.b {
padding: 0 2em;
width: 100%;
background: lightblue;
border: 2px solid black;
box-sizing: border-box;
}
<body>
<div class="a">Foo</div>
<div class="b">Bar</div>
</body>
box-sizing: border-box tells the browser to account for any border and padding in the values you specify for width and height. If you set an element's width to 100 pixels, that 100 pixels will include any border or padding you added, and the content box will shrink to absorb that extra width. This typically makes it much easier to size elements.

Body height 100% displaying vertical scrollbar

Out of curiosity, considering the example below, why does having the margin on the #container div cause a vertical scrollbar to appear in the browser? The container is much smaller in height than the body height which is set to 100%.
I have set the padding and margins to 0 for all elements except the #container. Note that I have deliberately omitted absolute positioning on the #container div. In this case how is the browser calculating the height of the body and how is the margin affecting it?
<!DOCTYPE html>
<html>
<head>
<style type="text/css">
* { padding:0; margin:0;}
html, body { height:100%; }
#container
{
padding:10px;
margin:50px;
border:1px solid black;
width: 200px;
height: 100px;
}
</style>
</head>
<body>
<div id='container'>
</div>
</body>
</html>
Example also on JSFiddle
If you paint the backgrounds of html and body (giving each its own color), you'll quickly notice that body is being shifted down along with #container, and #container itself isn't offset from the top of body at all. This is a side effect of margin collapse, which I cover in detail here (although that answer describes a slightly different setup).
It's this behavior that's causing the scrollbar to appear, since you've declared body to have 100% the height of html. Note that the actual height of body is unaffected, as margins are never included in height calculations.
Based upon #BoltClock♦'s answer, I fixed it by zeroing the margin...
so
html,body, #st-full-pg {
height: 100%;
margin: 0;
}
works where id "st-full-pg" is assigned to a panel div (which further contained panel-heading and panel-body)
A bit late, but maybe it helps someone.
Adding float: left; to #container removes the scrollbar, as W3C says:
•Margins between a floated box and any other box do not collapse (not even between a float and its in-flow children).
html,body {
height: 100%;
margin: 0;
overflow: hidden;
}
This worked for me
adding float:left; is nice, but will interfere with central horizontal positioning using margin:auto;
if you know how big your margin is, you can account for that in your height percentage using calc:
height: calc(100% - 50px);
browser support is good, but only IE11+
https://caniuse.com/#feat=calc
/*removes default margin & padding*/
html, body{
padding: 0px !important;
margin: 0px !important;
}
/*sets body height to max; and allows scrollbar as page content grows*/
body{
min-height: 100vh;
}
I have found a solution: add padding: 1px 0; to body prevents vertical scrollbars to appear
For those who are coming here for an easier to understand answer that even includes code samples, this answer (copied from here) is for you.
No JavaScript or definite pixel values (such as 100px) are required, just, pure CSS and percentages.
If your div is just sitting there on its own, height: 50% will mean 50% the height of the body. Normally, the height of the body is zero without any visible content, so 50% of that is just, well, zero.
This is the solution (based on this) (uncomment the background lines to get a visualisation of the padding):
/* Makes <html> take up the full page without requiring content to stretch it to that height. */
html
{
height: 100%;
/* background: green; */
}
body
{
/*
100% the height of <html> minus 1 multiple of the total extra height from the padding of <html>.
This prevents an unnecessary vertical scrollbar from appearing.
*/
height: calc(100% - 1em);
/* background: blue; */
}
/* In most cases it's better to use stylesheets instead of inline-CSS. */
div
{
width: 50%;
height: 50%;
background: red;
}
<div></div>
The above was written so that there would still be the usual padding. You could set the dimensions of the red div to 100% and still see padding on each side/end. If you don't want this padding, use this (although it doesn't look nice, I recommend you stick with the first example):
/* Makes <html> take up the full page without requiring content to stretch it to that height. */
html, body
{
height: 100%;
}
/* You can uncomment it but you wouldn't be able to see it anyway. */
/*
html
{
background: green;
}
*/
body
{
margin: 0;
/* background: blue; */
}
/* In most cases it's better to use stylesheets instead of inline-CSS */
div
{
width: 50%;
height: 50%;
background: red;
}
<div></div>
I saw this problem fixed before where you put all the contents of body in a div called wrap. Wrap's style should be set to position: relative; min-height: 100%;. To position #container div 50px from the top and left put a div inside wrap with a padding set to 50px. Margins will not work with wrap and the div we just made, but they will work in #container and everything inside it.
here's my fix on jsfiddle.
you can add non-breaking space into the body tag.
<body> <othertags>...</body>
html, body {
height: 100%;
overflow: hidden;
}
If you want to remove the body scrolling add the following style:
body {
height: 100%;
overflow: hidden;
}
Inspired by #BoltClock, I tried this and it worked, even when zoom out and in.
Browser: Chrome 51
html{
height: 100%;
}
body{
height: 100%;
margin: 0px;
position: relative;
top: -20px;
}
I guess body was shifted down 20px.
It works for me:
html,
body {
height: 100%;
height: -webkit-fill-available; // Chrome
}
// Firefox
#-moz-document url-prefix() {
body {
box-sizing: border-box;
margin: 0;
padding: 1px;
}
}
Add overflow: hidden; to html and body.
html, body {
height: 100%;
overflow: hidden;
}
I found a quick solution: try set height to 99.99% instead of 100%

How to make an element width: 100% minus padding?

I have an html input.
The input has padding: 5px 10px; I want it to be 100% of the parent div's width(which is fluid).
However using width: 100%; causes the input to be 100% + 20px how can I get around this?
Example
box-sizing: border-box is a quick, easy way to fix it:
This will work in all modern browsers, and IE8+.
Here's a demo: http://jsfiddle.net/thirtydot/QkmSk/301/
.content {
width: 100%;
box-sizing: border-box;
}
The browser prefixed versions (-webkit-box-sizing, etc.) are not needed in modern browsers.
This is why we have box-sizing in CSS.
I’ve edited your example, and now it works in Safari, Chrome, Firefox, and Opera. Check it out: http://jsfiddle.net/mathias/Bupr3/
All I added was this:
input {
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
}
Unfortunately older browsers such as IE7 do not support this. If you’re looking for a solution that works in old IEs, check out the other answers.
Use padding in percentages too and remove from the width:
padding: 5%;
width: 90%;
You can do it without using box-sizing and not clear solutions like width~=99%.
Demo on jsFiddle:
Keep input's padding and border
Add to input negative horizontal margin = border-width + horizontal padding
Add to input's wrapper horizontal padding equal to margin from previous step
HTML markup:
<div class="input_wrap">
<input type="text" />
</div>
CSS:
div {
padding: 6px 10px; /* equal to negative input's margin for mimic normal `div` box-sizing */
}
input {
width: 100%; /* force to expand to container's width */
padding: 5px 10px;
border: none;
margin: 0 -10px; /* negative margin = border-width + horizontal padding */
}
Use css calc()
Super simple and awesome.
input {
width: -moz-calc(100% - 15px);
width: -webkit-calc(100% - 15px);
width: calc(100% - 15px);
}​
As seen here: Div width 100% minus fixed amount of pixels
By webvitaly (https://stackoverflow.com/users/713523/webvitaly)
Original source: http://web-profile.com.ua/css/dev/css-width-100prc-minus-100px/
Just copied this over here, because I almost missed it in the other thread.
Assuming i'm in a container with 15px padding, this is what i always use for the inner part:
width:auto;
right:15px;
left:15px;
That will stretch the inner part to whatever width it should be less the 15px either side.
Here is the recommendation from codeontrack.com, which has good solution examples:
Instead of setting the width of the div to 100%, set it to auto, and be sure, that the <div> is set to display: block (default for <div>).
You can try some positioning tricks. You can put the input in a div with position: relative and a fixed height, then on the input have position: absolute; left: 0; right: 0;, and any padding you like.
Live example
Move the input box' padding to a wrapper element.
<style>
div.outer{ background: red; padding: 10px; }
div.inner { border: 1px solid #888; padding: 5px 10px; background: white; }
input { width: 100%; border: none }
</style>
<div class="outer">
<div class="inner">
<input/>
</div>
</div>
See example here: http://jsfiddle.net/L7wYD/1/
Maybe browsers have changed since this question was last answered, but this is the only thing that has ever worked reliably for me to accomplish this:
width: auto;
left: 0;
right: 0;
Then you can make the margins / padding anything you want and the element will not expand past its available width.
This is similar to #andology's answer from way back but if you make left/right both 0 then you can make margin and/or padding whatever you want. So this is always my default div.
Just understand the difference between width:auto; and width:100%;
Width:auto; will (AUTO)MATICALLY calculate the width in order to fit the exact given with of the wrapping div including the padding.
Width 100% expands the width and adds the padding.
What about wrapping it in a container. Container shoud have style like:
{
width:100%;
border: 10px solid transparent;
}
Try this:
width: 100%;
box-sizing: border-box;
For me, using margin:15px;padding:10px 0 15px 23px;width:100%, the result was this:
The solution for me was to use width:auto instead of width:100%. My new code was:
margin:15px;padding:10px 0 15px 23px;width:auto. Then the element aligned properly:
You can do this:
width: auto;
padding: 20px;

Border around 100% body height and width (HTML 4.01 Strict)

Okay, this is driving me crazy right now.
I want to have a border around my document. It should be nicely going around the whole window/viewport. So I define:
body {
border: 1px solid red;
}
When my document is in quirks mode, this works fine. At least in IE, which is my primary target here. A red border shows up at the very edges of my page, obviously because by predefined CSS body and html are set to fill the screen.
When going to standards mode by setting a HTML 4.01 strict DOCTYPE, body and html collapse to the real (smaller) size of the content, the border is drawn right through the middle of the screen. So I define:
body, html {
padding: 0px;
margin: 0px;
border: 0px none;
width: 100%;
height: 100%;
}
body {
border: 1px solid red;
}
And I get — scroll bars, scrolling exactly one pixel to show the bottom/right borders. However, I want that border visible right away.
Is there a no-bullshit (like "height: 99.9%;", "overflow: hidden;" or "switch back to quirks mode") method to get a border at 100%, without unnecessary scroll bars? IE-only is fine, cross-browser would be better, of course.
As SpliFF already mentioned, the problem is because the default (W3C) box model is 'content-box', which results in borders being outside of the width and height. But you want those to be within the 100% width and height you specified. One workaround is to select the border-box box model, but you can't do that in IE 6 and 7 without reverting to quirks mode.
Another solution works in IE 7, too. Just set html and body to 100% height and overflow to hidden to get rid of the window's scrollbars. Then you need to insert an absolutely positioned wrapper div that gets the red border and all content, setting all four box offset properties to 0 (so the border sticks to the edges of the viewport) and overflow to auto (to put the scrollbars inside the wrapper div).
There's only one drawback: IE 6 doesn't support setting both left and right and both top and bottom. The only workaround for this is to use CSS expressions (within a conditional comment) to explicitly set the width and height of the wrapper to the viewport's sizes, minus the width of the border.
To make it easier to see the effect, in the following example I enlarged the border width to 5 pixels:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
<head>
<title>Border around content</title>
<style type="text/css">
* {
margin: 0;
padding: 0;
}
html, body {
height: 100%;
overflow: hidden;
}
#wrapper {
position: absolute;
overflow: auto;
left: 0;
right: 0;
top: 0;
bottom: 0;
border: 5px solid red;
}
</style>
<!--[if IE 6]>
<style type="text/css">
#wrapper {
width: expression((m=document.documentElement.clientWidth-10)+'px');
height: expression((m=document.documentElement.clientHeight-10)+'px');
}
</style>
<![endif]-->
</head>
<body>
<div id="wrapper">
<!-- just a large div to get scrollbars -->
<div style="width: 9999px; height: 9999px; background: #ddd"></div>
</div>
</body>
</html>
P.S.: I just saw you don't like overflow: hidden, hmmm...
Update: I managed to get around using overflow: hidden by faking a border using four divs that stick to the edges of the viewport (you can't just overlay the whole viewport with a full-sized div, as all elements below it wouldn't be accessible any more). It's not a nice solution, but at least the normal scrollbars remain in their original position. I couldn't manage to let IE 6 simulate the fixed positioning using CSS expressions (got problems with the right and bottom divs), but it looked horribly anyway as those expressions are very expensive and rendering got tediously slow.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
<head>
<title>Border around content</title>
<style type="text/css">
* {
margin: 0;
padding: 0;
}
#border-t, #border-b, #border-l, #border-r {
position: fixed;
background: red;
z-index: 9999;
}
#border-t {
left: 0;
right: 0;
top: 0;
height: 5px;
}
#border-b {
left: 0;
right: 0;
bottom: 0;
height: 5px;
}
#border-l {
left: 0;
top: 0;
bottom: 0;
width: 5px;
}
#border-r {
right: 0;
top: 0;
bottom: 0;
width: 5px;
}
</style>
</head>
<body>
<!-- just a large div to get scrollbars -->
<div style="width: 9999px; height: 9999px; background: #ddd"></div>
<div id="border-t"></div><div id="border-b"></div>
<div id="border-l"></div><div id="border-r"></div>
</body>
</html>
You'll love this one.
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<style>
html {
height: 100%;
width: 100%;
display: table;
}
body {
display: table-row;
}
#wrapper {
display: table-cell;
border: 5px solid red;
}
</style>
</head>
<body>
<div id="wrapper"></div>
</body>
</html>
http://www.test.dev.arc.net.au/100-percent-border.html
I figured since tables keep a lot of "quirky" behavior even under standards mode they might be the solution. Turning the HTML element into a table is pretty funny though.
Before marking this down for not working in IE6 consider that's a very trivial issue to fix. The point is that using the table drawing algorithm is the solution, and a pure CSS solution is also possible:
<table class="outer"><tr><td class="inner"> ...page content...
Until CSS3 gives us inside borders and box-model switching you need two divs. The first to give the 100% height and the second to provide the border. Otherwise the border goes on the outside of the 100% height (ie, 1px+100%+1px)
BTW. You should collect some stats before going "IE only". IE does not have the marketshare it once did. Anywhere between 10 - 30% of your users may be on other browsers.
Here's a simple solution using only the html and body elements (no need for nested divs). It takes advantage of the special behaviour of the HTML element (it can't have an outer border so it must shrink to display it).
<html>
<head>
<style>
html {padding:0; margin:0; border:5px solid red;}
body {height:100%; padding:0; margin:0; border:0;}
</style>
</head>
<body>
</body>
</html>
It also a bit ugly, but giving the body
position:relative;
top:-1px;
left:-1px;
worked for me.
Try setting borders for the html element. The body element is only as high as it needs to but, as far as I remember, the html element takes the whole space (it's where you should set your background, too).
I'm not sure how borders look, I usually only set backgrounds.
border is out of 100% size. Try padding: -1px or margin: -1px.