Develop Reference

Is it possible to make a div work like how a "layer mask" would? [duplicate]

I have a background image that has background-size:cover; applied to it and then a series of divs overlaid which I would like to become individual clipping masks.
I've looked at the feature clip: rect(20px, 20px, 20px, 20px,); however as the divs are brought in through a CMS system, it will be inappropriate to define set sizes.
Is there a way of setting the div with a clipping mask property so that it clips the image anywhere the div is placed on the page?
I don't particularly want to use an image overlay either as this site will be responsive.

The clip-path CSS property can be applied to all HTML elements, SVG graphic elements and SVG container elements:
http://www.html5rocks.com/en/tutorials/masking/adobe/

If I understood correctly, you're simply looking for an overlay that will resize with the screen size, and the div with the background image?
In that case, if possible, why not simply append these divs INSIDE the div that needs clipping, like this. For this sample purpose I only used one div with a transparent background and a border applied to it. If you need to clip the image in a non-rectangular shape, you will need more divs (ex. for parallelogram, diamond, triangle shape, you'll need at least 2).
Also, sadly CSS doesn't allow for % borders, but I think this example is
You can also do it the other way around and place your img div inside the clipper divs; just a matter of what fits best...
body, html {
/* necessary for sizing children in % */
width: 100%;
height: 100%;
}
#tobeClipped {
width: 80%;
height: 40%;
position: relative;
background-image: url('http://cdn.theatlantic.com/static/infocus/ngpc112812/s_n01_nursingm.jpg');
background-size: cover;
}
#tobeClipped>div {
position: absolute;
}
#clippers {
width: 100%;
height: 100%;
border: 20px solid grey;
border-left-width: 100px;
box-sizing: border-box;
}
<div id="tobeClipped">
<div id="clippers"></div>
</div>
Please do clarify if this was not at all what you were looking for.

How to maintain relative positions/sizes of dynamically sized, stacked div's

This page centers and shrinks my logo to fit in the browser window. It uses a single PNG file and CSS flexbox with max-width/max-height. (View code)
This page animates the same logo. However, in order to limit the ripple effect to just the blue portion, some changes were needed (view code):
Logo split into two parts and stacked on top of each other (position:absolute).
Hard-coded the size of the logo. (No longer sized based on size of browser window)
I can't figure out two things:
How do I change the hard-coded sizes back to dynamic sizes based on the browser size? I also hard-coded the top and left, but if the two images are centered and scaled by the same ratio, they should line up properly without offsets.
How do I vertically/horizontally center the logo, again? I think my previous flexbox CSS doesn't work because the elements have position:absolute. Update: I was able to get centering to work again, but this involved more hard-coded width/heights.
I think I can do this via JavaScript, but is a pure CSS/HTML solution possible? (I have a feeling centering and dynamically sizing elements with position:absolute might not be possible). If JavaScript is disabled, the solution should gracefully degrade (the two parts of the logo are correctly aligned; the logo fits inside browser window).

Example: https://jsfiddle.net/2rdjfwhb/1/
It is possible to do both with CSS, you just need another wrapper element around the "logo" class. This wrapper element can be positioned naturally inside of a flexbox. After that it's just about calculating the ratio you need for your logo image and the ripple canvas.
.parent {
max-height: 100%;
max-width: 100%;
}
.logo {
width: 100%;
height: 100%;
position: relative; /* Parent handles centering this guy now */
}
.logo-ligature {
width: 100%;
height: 100%;
position: relative; /* Positioned for z-index */
pointer-events: none;
}
.logo-background {
background-image: url(https://cdn.glitch.com/b2cea96d-c2a3-486e-90d5-f60a651a36e3%2Fle_square_light_noborder.png?1553791477453);
background-size: contain;
background-position: center; /* Center the image */
background-repeat: no-repeat; /* Do not repeat the image */
width: 75%;
height: 75%;
position: absolute;
top: 12.5%;
left: 12.5%;
}

How to get background image cover with 100% height?

I'm using an image with a height of 5000px, and i want make it always appear 100% in width and height to cover the background, in mobile and desktop.
.main {
position: relative;
background: url('../images/background.png') no-repeat top center;
background-size: cover;
width: 100%;
}
This code does not work, it makes her not to appear. I always need to set a height, and the problem is that the mobile's height is different from the desktop.
So you could say.. 'you can set height: 100%'.. and I did .. but nothing happens, the image doesn't appear, only if i set with pxs.

UPDATE
I feel urged to update my answer since I apparently understood the question the wrong way. I'll leave the old version at the bottom since apparently a lot of people found it helpful even though it failed to answer the original question.
Since your background image is repeating itself, I'll assume you don't want the whole image, just whatever height you need. So, you need 2 things:
set a height on .main
get rid of background-size altogether
So, this should actually work for you:
.main {
position: relative;
background: url('../images/background.png') no-repeat top center;
width: 100%;
height: 100%;
}
If my assumption is correct, there's 1 more thing: you don't need a background over 5000px high to achieve your goal, just reduce it to 1px height (i.e. 1 line of your desired background) and change your css to:
.main {
position: relative;
background: url('../images/background.png') repeat-y top center;
background-size: cover;
width: 100%;
}
I hope this helps
OLD VERSION
Your .main has no height and height:100%; doesn't work because the elements containing it have no height themselves.
One possible solution would be to add this:
html, body, .main {
height:100%;
}
This might be exactly what you need, but you may also run into other problems with this solution. It all depends on what you're actually trying to achieve.
Other possible solutions:
Use viewport units
.main {
height:100vh;
}
Please be aware that some mobile devices interpret these differently from what you'd expect.
Add the background to the body itself
body {
background: url('../images/background.png') no-repeat top center;
background-size: cover;
}
As I wrote before: It's difficult to tell which solution is the best, it depends on your goal.

Have you tried adding this style?
html, body{ height: 100%;}
Then adding a height:100%; to your .main div

You are working with background-image... Keep in mind that the size of the rendered image has nothing to do with the image it self, but with the element created to contain it.
Now, if you want your image to appear at 100% height and width you can use the property background-size: contain, instead of cover.
This will tell the browser that your image should not be cropped (as long as you have a height set for the .main element).
It seems to me, that the kind of effect you want is easier done if you just use the <img> tag instead of css background.

I had a issue about flex box can`t fit the background height, and the code below suited for me. The rest background-size,repeat and position depends on yours.
html{
height:auto;
}
body{
display: flex;
flex-direction: column;
min-height: 100vh;
}

Position and Slider (see image)

Hi Stackoverflow,
I have some questions.
1) The image behind the black circle will be a full-width responsive slider. How can I put this image behind all the elements, in a way that Internet Explorer doesn't bug everything?
I know I can use position: absolute with z-index, but since I always had problems with IE and positions, I don't know (really), a better solution.
2) The background image of the black circle is also from the slider. Each BG it's directly linked with a image. Example: this colourful image will be linked to this black circle bg. Next slider will be another image with another bg.
How can I do this? :/

Try this:
As you said, set the position and z-index to the black image and append the same to body of the html page. Then change the slider images as earlier.
I hope it will work.

put the background image as a DIV and the next DIV "contents" will have all the contents
eg:
----contents ----
</div>
CSS
#bg-image {
background: url('http://t2.gstatic.com/images?q=tbn:ANd9GcSsYV2xklhQlwOFsqPY8OrL69n2F_naug6eShy67xcKm6QRFWmqXw');
background-size: cover;
width: 100%;
height: 100%;
position: fixed;
overflow: hidden;
}
#contents {
background: none;
width: 100%;
height: 100%;
position: absolute;
}

-- Take a look here Background image swap full
-- Other option is, Make a large size image and place it on background.
-- This is with css. Check this link perfect full page background image

Since the black circle doesn't change, what I did was: putting the black circle and the background image in a same image. And I just had to "control" the position of the text. It was a dumb solution, but it solved.

How to keep text over a huge image in proper position on all resolutions?

In my intro page I have a really big image in height and width to fit all the resolutions (more than 4000px in width) and I set it as below:
#source-image {
width: 100%;
position: absolute;
top: 0;
left: 0;
}
Then, I added some text over that image with these style properties:
.description {
position:absolute;
top:510px;
left:23px;
width:340px
}
And it looks properly (and as I want it to be shown) on my 15.6 inch laptop with 1366x768 resolution.
However when my roommate saw it on his high resolution monitor the description was not on the “right” position. Of course, I understand why this is happening.
My question is how can I keep dynamically the proper position of the description text in all resolutions?
Thank you very much.

Set the distance from the bottom, not from the top. Or set it in %.
EDIT: I've adapted one of my experiments into an example: http://dabblet.com/gist/2787061
The position of the description is set relative to the bottom and the left of the image container (the image is filling its entire container).
In the first case, the distances to the left and the bottom of the image container are fixed, in px.
In the second case, they are in % and change on resizing the browser window.
Basically, the rules that do the trick are
figcaption {
bottom: 5px;
left: 23px;
/* more rules here */
}
in the fist case (fixed distances, in px) and
figcaption.perc {
left: 10%;
bottom: 17%;
}
in the second case (percentage).
Also, please note that you don't need position: absolute or to set the top and the left properties for the image.
However, you do need to set position:relative on the parent of the description box.
For the image to fill the screen horizontally, you need to have margin:0; and padding:0; on the body element and width: 100%; and margin: 0; on the figure element. I've edited my example to reflect these changes http://dabblet.com/gist/2787061
For the image to fill the screen both horizontally and vertically, the easiest way is to not even use an img tag, but simply set the image as a background image for the body and set the height for both the html and the body elements to 100% - example http://dabblet.com/gist/2792929
Be careful for two reasons: one, this will really distort the image and can make it look ugly when resizing the browser window and two, if you need some content below the image you will need to give the the outer element position: absolute and set its top: 100%. Both these two aspects can be seen in the example I've linked to. You can simply remove the content below the image if you don't need it.

use position:relative; for the div that wraps the image, and position:absolute; for the text div

please set percentage
check the example- description box set in horizontal center,
first set position relative into wraper div
.description {
position:absolute;
top:510px;
left:50%;
width:340px;
margin:0 0 0 -170px
}