Develop Reference

% based, fixed and absolute positioned, nested elements?

Image:
I have a container div (yellow) which I’d like to keep at 50% width of the window. A child of that container is an image div (purple) that stretches to 100% of the parent container’s width. and there’s a sticky label (pink) on top of the image div (position: absolute so it can be offset relatively to the image). I'd like to keep that entire half of the screen fixed positioning so it stays sticky as I scroll.
There’s also a title under the image, and that title needs to be visible no matter if someone shrinks the window vertically. So in that scenario the image div should shrink vertically, if needed, in order for that title to be shown.
Basically I'm trying to have the image div always be 100% width of the parent container div. With the image div having a max % height so it can shrink vertically. Or have it keep a fixed aspect ratio (3:4 or whatever) when it shrinks vertically.
I'm trying to avoid using fixed pixels, or ems, in the entirety of my CSS. since the website needs to be stretchy/‘fluid’ vertically, because that title under the image has to show.
HTML looks roughly like:
<wrapper>
<left-column>
<normal text and scrollable stuff>
<right-column-yellow>
<image sticky label-pink>
<image div-purple>
<image title>
Sorry if this is damn confusing my brain is fried! Can anyone pls help me?

You can divide your left and right panel by using position fixed.
If I'm not wrong with your description, this is the answer.
<div class="wrapper">
<div class="left">
<p><!--Some very long text--></p>
</div>
<div class="right">
<div class="image">
<div class="label">Label</div>
<div class="title">Title</div>
</div>
</div>
Some CSS
.left,.right{
position: fixed;
width: 50%;
height: 100%;
display: inline-block;
}
.left{
left:0;
top: 0;
overflow: auto;
}
.right{
right: 0;
top:0;
background-color: yellow;
}
.right .image{
position: relative;
width: 100%;
height: 50%;
top: 50%;
left: 0;
background-color: #fff;
transform: translateY(-50%);
}
.right .image .label{
position: absolute;
left: 0;
right: 0;
top: -10px;
text-align: center;
width: 200px;
background-color: pink;
margin: auto;
}
.right .image .title{
position: absolute;
left: 0;
right: 0;
bottom: -40px;
text-align: center;
width: 200px;
background-color: #000;
margin: auto;
color: #fff;
font-size: 30px;
}
You can refer to my codeine as well.
https://codepen.io/masonwongcs/pen/WMJGZb

Create a div with aspect ratio 1:1 knowing only its height in percentage

I was wondering if you can help me with this.
I have a div (in white) where I need to put two circular buttons (in green) on the borders. Everything should be done with CSS.
It should look like this:
Screenshot
Now, the thing is that I don't know the size of the white div, and I won't know it at the time of creation, because it will get added to the DOM afterwards. All I know is that the white div has a percentage width and height relative to its future parent. So, at the time of creation, since it's not yet added, any calls to width(), height() or its css values won't work.
I've seen all those snippets that tell you how to make a div with a fixed aspect ratio. I need this now, I need the button to be 1:1, but all I know about the dimensions, is that it has to be 100% of the height of the white div (and therefore, its width should be equal as its height). All the examples I've seen assume that you know the width and to make the height keep the ratio. In my case, what I know is the height (100%) and I want the width to adapt.
I have no idea how to achieve this.
This is my snippet:
body{
background-color: #DCDCDC;
}
.container {
width: 50%;
height: 7%;
background: white;
border-radius: 20px;
position: absolute;
}
.arrow {
background: green;
border-radius: 20px;
height: 100%;
position: absolute;
}
.arrow:after{
content: "";
display: block;
padding-right: 100%;
}
.arrow:last-child {
right: 0;
}
<div class="container">
<div class="arrow"></div>
<div class="arrow"></div>
</div>
https://jsfiddle.net/7bxecL9m/
If you know how can I do this without entering any fixed value (jQuery use is of course valid), I'd really appreciate it.
Thanks.

There are many variables here:
Since container's height is % and circle radius is px units, one is static and the other one will resize.
The only way to preserve 1:1 with just html/css, considering the container's height % will resize circle's height as well, would be to isolate circle's div width & height to something static like px units.
Now, since you said no fixed dimensions, the only thing I can think of is to comment .arrow's 100% height, to prevent resizing other than 1:1, and nesting a div inside .arrow to restrain 1:1 with static units (ideally impacting .arrow directly would be less code but if you don't want/can't set them on that element, maybe you consider this).
If you want the circle to remain circular as the content expands, you need to dynamically adjust the height to match the width. You could use Javascript to achieve this, but your border-radius is tied to container's in px static units, since container will always be bigger something like border-radius: 50% wouldn't work for both, 50% radius of circle would never match 50% of container's (that is, if you care about radius alignment).
body {
background-color: #DCDCDC;
}
body,
html {
height: 100%;
}
.container {
width: 50%;
height: 37%;
background: white;
border-radius: 20px;
position: relative;
}
.arrow {
background: green;
border-radius: 20px;
/*height: 100%;*/
position: absolute;
overflow: hidden;
}
.bLimit {
height: 40px;
width: 40px;
line-height: 40px;
}
.arrow:after {
content: "";
display: block;
padding-right: 100%;
}
.arrow:last-child {
right: 0;
}
<div class="container">
<div class="arrow">
<div class="bLimit">button overflow</div>
</div>
<div class="arrow">
<div class="bLimit">button</div>
</div>
</div>

Why not doing a fixed width in percent for your arrow :
.arrow {
background: green;
border-radius: 20px;
height: 100%;
position: absolute;
width: 10%;
}

body{
background-color: #DCDCDC;
}
.container {
width: 50%;
height: 7%;
background: white;
border-radius: 20px;
position: absolute;
}
.container:after,.container:before{
content: " ";
display: block;
padding: 4%;
z-index: 999;
top: 0;
position:absolute;
background: green;
border-radius: 50%;
}
.container:before {
left: 0;
}
.container:after{
right: 0;
}
<div class="container">
</div>
You can achieve using before and after CSS pseudo selectors. You check this Example.

There is a posibility to get this result using a image (that won't show) of the required ratio.
In this case, the ratio is 1:1 so we will use an image of 50px (but it can be any size)
.container {
width: 300px;
height: 20px;
border: solid 1px blue;
margin: 40px;
position: relative;
}
.container:nth-child(2) {
height: 40px;
}
.container:nth-child(3) {
height: 60px;
}
.arrow {
height: 100%;
background-color: red;
opacity: 0.5;
position: absolute;
border-radius: 50%;
transform: translateX(-50%);
}
.arrow:last-child {
right: 0px;
transform: translateX(50%);
}
img {
height: 100%;
opacity: 0;
}
<div class="container">
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
</div>
<div class="container">
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
</div>
<div class="container">
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
<div class="arrow">
<img src="https://placehold.it/50x50">
</div>
</div>

Overlay the Contents of a DIV

I am trying to overlay 2 DIV's in my main parent DIV:
I want to overlay the the second div over on top of the first one. I have a problem overlaying it as I cannot keep it in the middle of the screen.
I have tried this to overlay:
The overlay works fine here, but my container is no longer center when I do this. How can I overlay and keep it center ?
div {
border: 5px solid red;
}
#first {
position: absolute;
z-index: 1;
border-color: orange;
}
#second {
position: absolute;
z-index: 2;
border-color: green;
}
<div id="container" class="container text-center">
<div id="first">Hi</div>
<div id="second">Hello</div>
</div>

Here is what you need to do (see width of both divs and text-align properties):
You can give them background color to see z-index works perfectly :)
#first {
text-align: center;
height: 300px;
width: 100%;
position: absolute;
z-index: 1;
}
#second {
text-align: center;
height: 300px;
width: 100%;
position: absolute;
z-index: 2;
}
<div id="container" class="container text-center">
<div id="first">Hi</div>
<div id="second">Hello</div>
</div>

When you position absolute, the positioned element is taken out of the document flow and positioned relative to the next highest parent element that is not the default position, i.e. not position: static;
The following will cause the absolute positioned children to stay within the containing div:
#container {
position: relative;
}

Your container's text is no longer centered because you have removed its children from the document flow. In essence, it has no content and collapses, and therefore, has no width to which to align the text.
One thing you could do is set the container to position: relative and full-width (i.e. width: 100vw), then set its children to width: 100%.
Then the inner divs will take on the width of their parent.
See this working JSFiddle.

#container {
position: relative;
width: 100%;
height: 100px;
background-color: yellow;
display: flex;
justify-content: center;
align-items: center;
}
#first{
position: absolute;
}
#second{
position: absolute;
}
<div id="container" class="container">
<div id="first">Hi</div>
<div id="second">Hello</div>
</div>

Your main issue is that the divs will not have any relative width to the parent div.
Therefore the text is still technically "centered" in each corresponding div because they're inheriting text-align: center from the container div.
However, the divs' widths will automatically be as wide as they needs to be (i.e. to fit the text, in this case).
You can remedy this one of two ways:
Force the divs to be centered
Give both divs the following (extra) CSS:
left: 50%;
width: 100%;
margin-left: -50%;
This will literally center them in their parent div.
or
Force the divs to be the same size as their parent
Give both the divs the following (extra) CSS:
top: 0;
bottom: 0;
left: 0;
right: 0;
This sets the divs to span their entire parent's height and width.
In both situations, you might need to make the .container class use position: relative, in order for the child divs to have something to be absolute to.
If you're using Bootstrap, there is no need to worry about this, as .container class already has this applied.
Hope one of these solutions helps you :)

Try this style:
#first,
#second {
left: 50%;
transform: translate(-50%, 0);
}
div {
border: 5px solid red;
}
#first {
position: absolute;
z-index: 1;
border-color: orange;
}
#second {
position: absolute;
z-index: 2;
border-color: green;
}
#first,
#second {
left: 50%;
transform: translate(-50%, 0);
}
<div id="container" class="container text-center">
<div id="first">Hi</div>
<div id="second">Hello</div>
</div>

make div bigger and animate bigger section upwards on hover

I am trying to animate a div upwards when a user hovers on the div.
I am able to animate the div making it bigger, however the animation happens downwards. I am trying to keep the bottom of the div remain in the same place, and have a smooth animating increasing the size of the div upwards.
See jsfiddle here which demonstrates what my code is currently doing.
Please see code below:
.box {
height: 170px;
padding-bottom: 15px;
width: 50%;
}
.content {
background-color: #e3e4e6;
height: 100%;
text-align: center;
}
.content:hover {
height: 110%;
}
<div class="box">
<div class="content">TEST</div>
</div>

You can do this using transform:scaleY() and set the transform-origin to bottom. I also put a margin-top:100px to see the effect better. Also you can use transition to make the scale smoother
You also need to scale back the text.
See here: jsfiddle
You need to scale the text back to it's original state in the same time that you scale the div. so if you scale the div 2 times. You need to scale back the text with 1/2 , same if you scale 3 times...scale back with 1/3
In this case you enlarge .content by 1.5 so you need to scale down the text inside by 1/1.5 = 0.66
Code:
.box {
height: 170px;
padding-bottom: 15px;
width: 50%;
}
.content {
background-color: #e3e4e6;
height: 100%;
text-align: center;
margin-top: 300px;
transition:0.3s;
}
.content:hover p {
transform: scaleY(0.66)
}
.content:hover {
transform: scaleY(1.5);
transform-origin: bottom;
}
<div class="box">
<div class="content">
<p>
TEST
</p>
</div>
</div>

Try it like this (I have no other idea...): You can give to the class "box" a bigger height (I put a red border around, so you can see it) than the class "content". After that, you can use flexbox, to put the class "content" on the bottom. After that, you can do it with hover to change your heigth upwards and fill it. With transition you can make a nice animation. I hope this is good enough. Perhaps there is also a way with jQUery at the moment I havn't got an idea. Let me know, if this helps you (I'm not sure if I understanded the question well) - Cheers. (Important: This heights and so on are just random values for testing)
.box {
display: flex;
justify-content: flex-end;
flex-direction: column;
height: 100px;
border: 1px solid red;
}
.content {
background-color: #e3e4e6;
height: 50px;
width: 100%;
text-align: center;
-webkit-transition: height 1s;
/* Safari */
transition: height 1s;
}
.content:hover {
height: 100%;
}
<div class="box">
<div class="content">TEST</div>
</div>

If you just want to use css, just use:
.content:hover {
margin-top: -50px;
height: 110%;
}
See jsFiddle

since there isn't any space at top to expand, you may give an extra margin initially and remove it on hover like this JsFiddle -
.box {
height: 170px;
padding-bottom: 15px;
width: 50%;
}
.content {
background-color: #e3e4e6;
height: 100%;
text-align: center;
margin-top:25px;
}
.content:hover {
height: 110%;
margin-top:0;
}

Set top property with the value of height - 100 * -1
https://jsfiddle.net/x3cL1cpt/7/
.content:hover {
height: 110%;
top: -10%;
position: relative;
}
Why position relative? It's because I move the box, but without modifying the space that the box occuped. If you need to modify that space, change top with margin-top.

Replace this CSS with your current, needed to add transition:
.box {
height: 170px;
padding-bottom: 15px;
width: 50%;
}
.content {
background-color: #e3e4e6;
height: 100%;
text-align: center;
transition: 1s all ease;
}
.content:hover {
transform: scaleY(1.2);
transform-origin: bottom right;
}

Vertically centered absolute position div inside relative position parent - Works in Chrome, but centers to body in Safari etc?

I am trying to vertically center some text over an image that appears on a mouseover. I have come to a solution that works with chrome (15.0.874.106) on a mac (10.7.2), but it seems to have issues in Safari (5.1.1), odd since they are both webkit based. I believe it also has the same problem in Firefox.
The text is vertically centered in relation to the parent div in chrome, but seems to center to the body or window in Safari. Am I doing something wrong or does anyone have a better solution?
jsbin: http://jsbin.com/iceroq
CSS:
.content {
width: 300px;
position: relative;
}
.content-text {
width: 100%;
height: 100%;
background: black;
position: absolute;
top: 0;
left: 0;
text-align: center;
display: none;
}
HTML:
<div class="content">
<div class="content-image">
<img src="http://placehold.it/300x500/E01B4C" />
</div>
<div class="content-text">
Google
</div>
</div>
.content-text a {
color: white;
position: relative;
top: 50%;
margin-top: -0.5em;
}
JS:
$(document).ready(function() {
$('.content').hover(
function() {
$(this).children('.content-text').show();
}, function() {
$(this).children('.content-text').hide();
});
});

I edited your jsbin: http://jsbin.com/iceroq/3
The edits were all CSS changes to .content-text a. Making the link absolutely positioned and giving it a height allows you to know what margin-top to give it (half of the height).
.content-text a {
display: block;
width: 100%;
height: 20px;
position: absolute;
top: 50%;
margin-top: -10px;
color: white;
}