I want to scale an iFrame through CSS to width: 100%, and the height should scale proportionally to the width.
With an <img> tag this works fine.
Both the image and the iFrame have defined width and height in the html.
Here some examples:
<html>
<style>
#a{ width: 500px; }
img{ width: 100%; height: auto }
</style>
<body>
<div id="a">
<img src="http://lorempixel.com/200/150/" width="200" height="150" />
</div>
</body>
This works great on images, but I would like the same behaviour for iFrames:
<html>
<style>
#a{ width: 900px; background: grey;}
iframe{ width: 100%; height: auto }
</style>
<body>
<div id="a">
<iframe width="560" height="315" src="http://www.youtube.com/embed/RksyMaJiD8Y" frameborder="0" allowfullscreen></iframe>
</div>
</body>
The iFrame renders 100% wide but does not scale it's height proportional like the image does.
This question is related to
css
iframe
responsive-design
None of these solutions worked for me inside a Weebly "add your own html" box. Not sure what they are doing with their code. But I found this solution at https://benmarshall.me/responsive-iframes/ and it works perfectly.
CSS
.iframe-container {
overflow: hidden;
padding-top: 56.25%;
position: relative;
}
.iframe-container iframe {
border: 0;
height: 100%;
left: 0;
position: absolute;
top: 0;
width: 100%;
}
/* 4x3 Aspect Ratio */
.iframe-container-4x3 {
padding-top: 75%;
}
HTML
<div class="iframe-container">
<iframe src="https://player.vimeo.com/video/106466360" allowfullscreen></iframe>
</div>
@Anachronist is closest here, @Simone not far off. The caveat with percentage padding on an element is that it's based on its parent's width, so if different to your container, the proportions will be off.
The most reliable, simplest answer is:
body {_x000D_
/* for demo */_x000D_
background: lightgray;_x000D_
}_x000D_
.fixed-aspect-wrapper {_x000D_
/* anything or nothing, it doesn't matter */_x000D_
width: 60%;_x000D_
/* only need if other rulesets give this padding */_x000D_
padding: 0;_x000D_
}_x000D_
.fixed-aspect-padder {_x000D_
height: 0;_x000D_
/* last padding dimension is (100 * height / width) of item to be scaled */_x000D_
padding: 0 0 56.25%;_x000D_
position: relative;_x000D_
/* only need next 2 rules if other rulesets change these */_x000D_
margin: 0;_x000D_
width: auto;_x000D_
}_x000D_
.whatever-needs-the-fixed-aspect {_x000D_
position: absolute;_x000D_
top: 0;_x000D_
left: 0;_x000D_
width: 100%;_x000D_
height: 100%;_x000D_
/* for demo */_x000D_
border: 0;_x000D_
background: white;_x000D_
}<div class="fixed-aspect-wrapper">_x000D_
<div class="fixed-aspect-padder">_x000D_
<iframe class="whatever-needs-the-fixed-aspect" src="/"></iframe>_x000D_
</div>_x000D_
</div>I like this solution best. Simple, scalable, responsive. The idea here is to create a zero-height outer div with bottom padding set to the aspect ratio of the video. The iframe is scaled to 100% in both width and height, completely filling the outer container. The outer container automatically adjusts its height according to its width, and the iframe inside adjusts itself accordingly.
<div style="position:relative; width:100%; height:0px; padding-bottom:56.25%;">
<iframe style="position:absolute; left:0; top:0; width:100%; height:100%"
src="http://www.youtube.com/embed/RksyMaJiD8Y">
</iframe>
</div>
The only variable here is the padding-bottom value in the outer div. It's 75% for 4:3 aspect ratio videos, and 56.25% for widescreen 16:9 aspect ratio videos.
I suppose this is a cleaner approach.
It works with inline height and width properties (I set random value in the fiddle to prove that) and with CSS max-width property.
HTML:
<div class="wrapper">
<div class="h_iframe">
<iframe height="2" width="2" src="http://www.youtube.com/embed/WsFWhL4Y84Y" frameborder="0" allowfullscreen></iframe>
</div>
<p>Please scale the "result" window to notice the effect.</p>
</div>
CSS:
html,body {height: 100%;}
.wrapper {width: 80%; max-width: 600px; height: 100%; margin: 0 auto; background: #CCC}
.h_iframe {position: relative; padding-top: 56%;}
.h_iframe iframe {position: absolute; top: 0; left: 0; width: 100%; height: 100%;}
Big difference between an image and an iframe is the fact that an image keeps its aspect-ratio. You could combine an image and an iframe with will result in a responsive iframe. Hope this answerers your question.
Check this link for example : http://jsfiddle.net/Masau/7WRHM/
HTML:
<div class="wrapper">
<div class="h_iframe">
<!-- a transparent image is preferable -->
<img class="ratio" src="http://placehold.it/16x9"/>
<iframe src="http://www.youtube.com/embed/WsFWhL4Y84Y" frameborder="0" allowfullscreen></iframe>
</div>
<p>Please scale the "result" window to notice the effect.</p>
</div>
CSS:
html,body {height:100%;}
.wrapper {width:80%;height:100%;margin:0 auto;background:#CCC}
.h_iframe {position:relative;}
.h_iframe .ratio {display:block;width:100%;height:auto;}
.h_iframe iframe {position:absolute;top:0;left:0;width:100%; height:100%;}
note: This only works with a fixed aspect-ratio.
You could use viewport units here instead of %. Like this:
iframe {
max-width: 100vw;
max-height: 56.25vw; /* height/width ratio = 315/560 = .5625 */
}
body {_x000D_
margin: 0;_x000D_
}_x000D_
.a {_x000D_
max-width: 560px;_x000D_
background: grey;_x000D_
}_x000D_
img {_x000D_
width: 100%;_x000D_
height: auto_x000D_
}_x000D_
iframe {_x000D_
max-width: 100vw;_x000D_
max-height: 56.25vw;_x000D_
/* 315/560 = .5625 */_x000D_
}<div class="a">_x000D_
<img src="http://lorempixel.com/560/315/" width="560" height="315" />_x000D_
</div>_x000D_
_x000D_
<div class="a">_x000D_
<iframe width="560" height="315" src="http://www.youtube.com/embed/RksyMaJiD8Y" frameborder="0" allowfullscreen></iframe>_x000D_
</div>Source: Stackoverflow.com