Center a fixed div with unknown width [duplicate] - css

This question already has answers here:
How can I horizontally center an element?
(133 answers)
Closed 8 years ago.
I have a div in body:
<div class="wrapper" style="position: fixed">
<img src="#">
</div>
The <img> has its intrinsic width and height (and unknown). So how do I do to center the <div> in srceen (by CSS, not Jquery or Javascript)?

Demo
css
img {
position:fixed;
top:0;
bottom:0;
left:0;
right:0;
margin:auto;
background: #000;
}

I suppose you want the .wrapper to have a fixed position because you want to have it as a header or footer. This makes it wrap to its contents, so you need to explicitly tell it to stretch to 100% width. Next, img are displayed inline. Therefore, to use the auto margin trick, you need to set its display to block:
.wrapper {
position: fixed;
width: 100%;
background: lightblue;
}
img {
display: block;
margin: 0 auto;
}
Working jsfiddle here: http://jsfiddle.net/7swkv/

Related

CSS Image position not what i wanted [duplicate]

This question already has answers here:
How can I center an absolutely positioned element in a div?
(37 answers)
How to center a "position: absolute" element
(31 answers)
Closed 2 years ago.
im trying to put my image on the middle top off my box. I'm sorry if this is a stupid question but I'm new to coding and I'm young. I searched on the code, everything's fine except this part. It makes my image is on like the middle mid, a bit on the left which is not what I want. Thanks
.profile img
{
position: absolute!important;
left:calc(50% - 60%px)!important;
border: 10px solid #fff!important;
}
this is what it gives me
This will also help;
.profile{
position:relative; /* set whatever height and width to this div */
}
.profile img{
position: absolute;
left:50%;
top:50%;
transform:translate(-50%,-50%);
border: 10px solid #fff;
}
Try using Flexbox containers. Using justify-content and align-items, you should be able to put your image at the top center of your div without using absolutes. The W3 links show examples of both properties--combine them and you should achieve your desired result.
Using margin:auto (by making img tag as display:block)
div {background: yellow; height: 400px;}
img {border-radius:50%; margin:auto;display:block;}
<div class="wrapper">
<img src="https://picsum.photos/100" />
</div>
Using Flexbox
div {background: yellow; height: 400px; display: flex; justify-content:center;}
img {height: 100px; border-radius: 50%;}
<div class="wrapper">
<img src="https://picsum.photos/100" />
</div>

Understanding the parent child relationship (fixed blocks) CSS

I've been enjoying and having success mocking up webpages with CSS. But then I decided to play with a "fixed menu" and my understanding is now not so clear.
So my brief knowledge make a blank HTML doc and then create a "container" div and place all your further elements within the "parent" container. No problem with this and all has been well with floating elements and such.
But when placing a "fixed" element within my parent div I'm lost as to why the fixed element observes the parent's left margin and ignores it's right margin.
html, body{margin: 0; padding: 0;}
#container
{
margin:0px auto;
width:90%;
height:500px;
background:#A8A8A8;
}
.fixed-menu
{
position: fixed;
height: 50px;
width:100%;
background-color: #00a087;
}
<body>
<div id="container">
<div class="fixed-menu"></div>
</div>
</body>
So with the above the "fixed" block does align with the left margin of the parent container but runs completely to the right edge of the browser page. I have figured out that I can make the fixed block 90% and resolve the issue but I don't understand why. Why would the block not be 90% of the parent "container" block.
I look forward to you knowledge.
Thanks
Update your css like below to achieve your desired result. Inherit your width from the parent instead of using 100%.
.fixed-menu
{
position: fixed;
height: 50px;
width:inherit;
left:auto;
right:auto;
background-color: #00a087;
}
DEMO
as stated by #freestock.tk, a fixed element is "fixed" to the screen viewport.
the width (and height of set in %) is computed relative to the screen viewport.
it looks like it's aligned to left margin of the parent container because you did not positioned it with left or right css properties, it's not constrained by the parent container, it is just at the same horizontal position in this peculiar case.
if you set
left:0;
it will align to the left margin of the viewport and ignore the parent container, this should help you better understand his fixed positioning.
html, body{margin: 0; padding: 0;}
#container
{
margin:0px auto;
width:90%;
height:500px;
background:#A8A8A8;
}
.fixed-menu
{
position: fixed;
left:0;
height: 50px;
width:100%;
background-color: #00a087;
}
<body>
<div id="container">
<div class="fixed-menu"></div>
</div>
</body>
You where almost there, just add to .fixed-menu few css rules more :
.fixed-menu {
left:0;
right:0;
margin:0 auto;
width: 95% // now you can change width and fixed element will be centered always
}

How do you make a div 100% - some px? [duplicate]

This question already has answers here:
Is it possible to make a div 50px less than 100% in CSS3? [duplicate]
(6 answers)
Closed 9 years ago.
I have two divs. I want the one on the left to be 200px. I want the one on the right to fill up whatever the screen width is - 200px. In other words the div on the right should be 100% of the available space after the div on the left is drawn. Is there a pure css way of doing this?
rough example
<div class='l'></div><div class='r'></div>
.l {
display:inline-block;
background:green;
width:100px;
height:20px;
}
.r {
background:red;
height:20px;
}
Working jsFiddle Demo
Consider the following markup:
<div id="fixed">Fixed Width</div>
<div id="flexible">Flexible Width</div>
And in your CSS:
#fixed {
background: red;
float: left;
width: 200px;
}
#flexible {
margin-left: 200px;
background: green;
}

CSS Absolute positioning 100% height less padding without JS

The following code has a DIV that needs to be positioned at the top of the container, another at the bottom and then the content needs to come through in the middle.
<div style="position:absolute; top:0; width:100%; height:40px"></div>
<div class="howto"></div>
<div style="position:absolute; bottom:0; width:100%; height:40px"></div>
So we don't know the height of the containing DIV. How without JS can the div with class howto have the height of the container DIV less the height of the absolute positioned div at the top and bottom so as to contain content between these 2 DIVs.
For what you wish to accomplish, this is one possible solution:
#tinkerbin: http://tinkerbin.com/QsaCPgR6
HTML:
<div class="container">
<div class="header"></div>
<div class="howto">
Has height set to auto. You may change that if you want to.
</div>
<div class="footer"></div>
</div>
CSS:
.container {
position: relative;
padding: 40px 0; /* top and bottom padding = .header and .footer padding*/
}
.header,
.footer {
position: absolute;
height: 40px;
width: 100%;
}
.header {
top: 0;
}
.footer {
bottom: 0;
}
.howto {
height: /*specifiy one if you wish to*/;
}
As far as I know there isn't a pure CSS way to do what you're trying to do without JS.
See this previous post on SA:
Make a div fill the height of the remaining screen space

Fluid image, vertical align (middle) within width fluid DIV

So yet another question about vertically aligning an image within a div, but I think mine is different than the others I've found on here. I can't seem to find a solution that works for my situation.
I have a DIV that is 100% width (to it's container, which is floating left and has a set pixel width) and has a set pixel height. I have an image inside that I am positioning absolute to get it to the background of content within the DIV. The image is fluid with a width of 100%.
All works well, but I want to get the image to vertically align to the middle of the container and height is unknown.
Here is some sample code that shows what I'm trying to do:
<div class="container">
<div class="image-wrapper">
<img src="http://farm5.staticflickr.com/4111/4968056789_d872094672_o.jpg"
width="100%" />
</div>
<p>Some text</p>
</div>
And some sample CSS:
.container {
width:100%;
margin-top:10px;
height:100px;
overflow:hidden;
}
.image-wrapper {
position: relative;
}
.image-wrapper > img {
position: absolute;
z-index: -1;
}
p {
text-align: center;
padding-top: 10px;
color:#fff;
font-weight: bold;
}
But the flower should show up with it's center visible within the container div.
Any thoughts? I'm trying to avoid any Javascript sizing (the outer container, not shown in this sample, is already being sized). I'm not opposed to more DIVs, tables.. whatever you got!
A jsFiddle to demo this:
http://jsfiddle.net/JonMcL/sNz9h/
Why not go for the background-image property? That allows vertical centering...
http://jsfiddle.net/urrWS/
Assuming you want to only scale the image down and not stretch it beyond its native resolution this should do the trick. A little bit of jQuery is involved but it's minimal. Essentially, this adjusts the top-margin of the IMG on the window.resize event.
HTML
<div id="container">
<img id="image" src="image.jpg"> <!-- native size is 480x300 -->
</div>
CSS
#container {
margin: auto;
width: 80%;
height: 300px;
border: 1px solid gray;
}
#image {
display: block;
width: 100%;
max-width: 480px;
margin: auto;
}
jQuery
function adjustImage() {
$("#image").css('margin-top', ($("#container").height() - $("#image").height()) / 2);
}
$(window).load(function() {
adjustImage();
$(window).resize(function() {
adjustImage();
});
});
If I get what you need I would suggest setting the background image via css, then you can set the position correctly etc.
.container {
width:100%;
margin-top:10px;
background-image:url("http://farm5.staticflickr.com/4111/4968056789_d872094672_o.jpg");
background-repeat:no-repeat;
background-position:left center;
height:100px;
overflow:hidden;
}
http://jsfiddle.net/sNz9h/6/

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