How to apply CSS to iframe?

Question

I have a simple page that has some iframe sections (to display RSS links). How can I apply the same CSS format from the main page to the page displayed in the iframe?

Sleety

It is possible but only if the iframe's domain is the same as the parent – Cytokinesis

gawpertron, just to clarify, are you saying if I use iFrame content from some other domain that I don't control, there is no way for me to control the CSS for that content? – Olivares

Can you list a link to the page so that we might just be able to view our changes. – Thaddeus

The domain, port and protocol have to be the same, doesn't work with subdomains either. – Edvard

Answer 1

Edit: This does not work cross domain unless the appropriate CORS header is set.

There are two different things here: the style of the iframe block and the style of the page embedded in the iframe. You can set the style of the iframe block the usual way:

<iframe name="iframe1" id="iframe1" src="empty.htm" 
        frameborder="0" border="0" cellspacing="0"
        style="border-style: none;width: 100%; height: 120px;"></iframe>

The style of the page embedded in the iframe must be either set by including it in the child page:

<link type="text/css" rel="Stylesheet" href="Style/simple.css" />

Or it can be loaded from the parent page with Javascript:

var cssLink = document.createElement("link");
cssLink.href = "style.css"; 
cssLink.rel = "stylesheet"; 
cssLink.type = "text/css"; 
frames['iframe1'].document.head.appendChild(cssLink);

Adlay

Please note, it seems to me like some of the examples posted before are now invalid for html5. You can access the frame's contents as follows: document.getElementById("myframe").contentDocument. Embedding the css still doesn't seem to work for me though. – Classical

link may only appear in the HEAD – Frailty

Worked for me only when I did ...document.head.appendChild(cssLink) - Firefox and Safari. – Galbanum

Does this actually work cross-domain? I don't think it would. – Since

Just so no1 else has to test it to find out: correct, it doesn't work cross-domain. Immediately upon doing frames['name'] you get "Unsafe JavaScript attempt to access frame with URL blah from frame with URL blah. Domains, protocols and ports must match." – Symbolism

Answer 2

I met this issue with Google Calendar. I wanted to style it on a darker background and change font.

Luckily, the URL from the embed code had no restriction on direct access, so by using PHP function file_get_contents it is possible to get the entire content from the page. Instead of calling the Google URL, it is possible to call a php file located on your server, ex. google.php, which will contain the original content with modifications:

$content = file_get_contents('https://www.google.com/calendar/embed?src=%23contacts%40group.v.calendar.google.com&ctz=America/Montreal');

Adding the path to your stylesheet:

$content = str_replace('</head>','<link rel="stylesheet" href="http://www.yourwebsiteurl.com/google.css" /></head>', $content);

(This will place your stylesheet last just before the head end tag.)

Specify the base url form the original url in case css and js are called relatively:

$content = str_replace('</title>','</title><base href="https://www.google.com/calendar/" />', $content);

The final google.php file should look like this:

<?php
$content = file_get_contents('https://www.google.com/calendar/embed?src=%23contacts%40group.v.calendar.google.com&ctz=America/Montreal');
$content = str_replace('</title>','</title><base href="https://www.google.com/calendar/" />', $content);
$content = str_replace('</head>','<link rel="stylesheet" href="http://www.yourwebsiteurl.com/google.css" /></head>', $content);
echo $content;

Then you change the iframe embed code to:

<iframe src="http://www.yourwebsiteurl.com/google.php" style="border: 0" width="800" height="600" frameborder="0" scrolling="no"></iframe>

Good luck!

Madame

You can call that hacking by definition if you want. But you didn't offer any better solution... This solution is not a way to dammage Google service or to trick people in a way to exploit their weakness. – Madame

I would kill for a way to make this solution work with google docs. Its throwing all sorts of javascript errors. "Uncaught TypeError: Cannot read property 'a' of undefined " – Anabel

@ChrisHoughton FYI, it basically isn't. It might, however, render the entire iframe pointless (one reason for using iframes, for instance, is for security purposes, e.g. with card payments, and if you do what is suggested here you'll probably cause yourself problems). – Shipment

By doing this you are always getting the calendar as a non-logged in user. With the normal html iframe the user would see their own personal calendar if they were logged into google, but since your PHP code can't know the users Google session ID it can't fetch their personal calendar. – Ellissa

Answer 3

If the content of the iframe is not completely under your control or you want to access the content from different pages with different styles you could try manipulating it using JavaScript.

var frm = frames['frame'].document;
var otherhead = frm.getElementsByTagName("head")[0];
var link = frm.createElement("link");
link.setAttribute("rel", "stylesheet");
link.setAttribute("type", "text/css");
link.setAttribute("href", "style.css");
otherhead.appendChild(link);

Note that depending on what browser you use this might only work on pages served from the same domain.

Dissent

Might be worth noting that the same origin policy will stop this working if the page is on a different domain. – Mercier

In the same line of thinking but more succinct: <iframe onload="this.contentDocument.body.style.overflow='hidden';" /> – Conquer

Even Firefox has gone CORS – Intaglio

The snippet <iframe id="iframe-payment2" onload="this.style.height='1600px';" frameborder="0" scrolling="no" height="1800" src="<?php echo "//" . $_SERVER['HTTP_HOST']; ?>/payment/" ></iframe> worked for me. – Residency

var frm = frames['frame'].document; should be var frm = window.frames['frame'].document;. Nevertheless, still doesn't work, document comes back as undefined. – Nigro

Answer 4

var $head = $("#eFormIFrame").contents().find("head");
               
$head.append($("<link/>", {
    rel: "stylesheet",
    href: url,
    type: "text/css"
}));

Selfinterest

Answer 5

Here is how to apply CSS code directly without using <link> to load an extra stylesheet.

var head = jQuery("#iframe").contents().find("head");
var css = '<style type="text/css">' +
          '#banner{display:none}; ' +
          '</style>';
jQuery(head).append(css);

This hides the banner in the iframe page. Thank you for your suggestions!

Sergeant

Does this also get around the CORS restrictions? – Carrefour

@ArtemisPrime: do you think the people writing these specs would have missed append(element)? of course it doesn't. you could have read that spec or tested yourself. – Resort

Answer 6

If you control the page in the iframe, as hangy said, the easiest approach is to create a shared CSS file with common styles, then just link to it from your html pages.

Otherwise it is unlikely you will be able to dynamically change the style of a page from an external page in your iframe. This is because browsers have tightened the security on cross frame dom scripting due to possible misuse for spoofing and other hacks.

This tutorial may provide you with more information on scripting iframes in general. About cross frame scripting explains the security restrictions from the IE perspective.

Oxalate

Answer 7

An iframe is universally handled like a different HTML page by most browsers. If you want to apply the same stylesheet to the content of the iframe, just reference it from the pages used in there.

Ganesha

@hangry but... how? – Skerrick

Answer 8

The above with a little change works:

var cssLink = document.createElement("link") 
cssLink.href = "pFstylesEditor.css"; 
cssLink.rel = "stylesheet"; 
cssLink.type = "text/css"; 
                
//Instead of this
//frames['frame1'].document.body.appendChild(cssLink);
//Do this
    
var doc=document.getElementById("edit").contentWindow.document;
                
//If you are doing any dynamic writing do that first
doc.open();
doc.write(myData);
doc.close();
    
//Then append child
doc.body.appendChild(cssLink);

Works fine with ff3 and ie8 at least

Rationalism

Answer 9

The following worked for me.

var iframe = top.frames[name].document;
var css = '' +
          '<style type="text/css">' +
          'body{margin:0;padding:0;background:transparent}' +
          '</style>';
iframe.open();
iframe.write(css);
iframe.close();

Solubilize

Answer 10

Expanding on the above jQuery solution to cope with any delays in loading the frame contents.

$('iframe').each(function(){
    function injectCSS(){
        $iframe.contents().find('head').append(
            $('<link/>', { rel: 'stylesheet', href: 'iframe.css', type: 'text/css' })
        );
    }

    var $iframe = $(this);
    $iframe.on('load', injectCSS);
    injectCSS();
});

Diatessaron

Answer 11

You can try this:

$('iframe').load( function() {
  $('iframe').contents().find("head").append(
    $("<style type='text/css'> .my-class{ display:none; } </style>")
  );
});

Anastrophe

If your iframe comes from different origin, the CORS mechanism will not allow this workarround. – Immolate

Answer 12

If you want to reuse CSS and JavaScript from the main page maybe you should consider replacing <IFRAME> with a Ajax loaded content. This is more SEO friendly now when search bots are able to execute JavaScript.

This is jQuery example that includes another html page into your document. This is much more SEO friendly than iframe. In order to be sure that the bots are not indexing the included page just add it to disallow in robots.txt

<html>
  <header>
    <script src="/js/jquery.js" type="text/javascript"></script>
  </header>
  <body>
    <div id='include-from-outside'></div>
    <script type='text/javascript'>
      $('#include-from-outside').load('http://example.com/included.html');
    </script> 
  </body>
</html>

You could also include jQuery directly from Google: http://code.google.com/apis/ajaxlibs/documentation/ - this means optional auto-inclusion of newer versions and some significant speed increase. Also, means that you have to trust them for delivering you just the jQuery ;)

Simmon

Answer 13

My compact version:

<script type="text/javascript">
$(window).load(function () {
    var frame = $('iframe').get(0);
    if (frame != null) {
        var frmHead = $(frame).contents().find('head');
        if (frmHead != null) {
            frmHead.append($('style, link[rel=stylesheet]').clone()); // clone existing css link
            //frmHead.append($("<link/>", { rel: "stylesheet", href: "/styles/style.css", type: "text/css" })); // or create css link yourself
        }
    }   
});
</script>

However, sometimes the iframe is not ready on window loaded, so there is a need of using a timer.

Ready-to-use code (with timer):

<script type="text/javascript">
var frameListener;
$(window).load(function () {
    frameListener = setInterval("frameLoaded()", 50);
});
function frameLoaded() {
    var frame = $('iframe').get(0);
    if (frame != null) {
        var frmHead = $(frame).contents().find('head');
        if (frmHead != null) {
            clearInterval(frameListener); // stop the listener
            frmHead.append($('style, link[rel=stylesheet]').clone()); // clone existing css link
            //frmHead.append($("<link/>", { rel: "stylesheet", href: "/styles/style.css", type: "text/css" })); // or create css link yourself
        }
    }
}
</script>

...and jQuery link:

<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.9.1.min.js" type="text/javascript"></script>

Dasyure

Answer 14

As many answers are written for the same domains, I'll write how to do this in cross domains.

First, you need to know the Post Message API. We need a messenger to communicate between two windows.

Here's a messenger I created.

/**
 * Creates a messenger between two windows
 *  which have two different domains
 */
class CrossMessenger {

    /**
     * 
     * @param {object} otherWindow - window object of the other
     * @param {string} targetDomain - domain of the other window
     * @param {object} eventHandlers - all the event names and handlers
     */
    constructor(otherWindow, targetDomain, eventHandlers = {}) {
        this.otherWindow = otherWindow;
        this.targetDomain = targetDomain;
        this.eventHandlers = eventHandlers;

        window.addEventListener("message", (e) => this.receive.call(this, e));
    }

    post(event, data) {

        try {
            // data obj should have event name
            var json = JSON.stringify({
                event,
                data
            });
            this.otherWindow.postMessage(json, this.targetDomain);

        } catch (e) {}
    }

    receive(e) {
        var json;
        try {
            json = JSON.parse(e.data ? e.data : "{}");
        } catch (e) {
            return;
        }
        var eventName = json.event,
            data = json.data;

        if (e.origin !== this.targetDomain)
            return;

        if (typeof this.eventHandlers[eventName] === "function") 
            this.eventHandlers[eventName](data);
    }

}

Using this in two windows to communicate can solve your problem.

In the main windows,

var msger = new CrossMessenger(iframe.contentWindow, "https://iframe.s.domain");

var cssContent = Array.prototype.map.call(yourCSSElement.sheet.cssRules, css_text).join('\n');
msger.post("cssContent", {
   css: cssContent
})

Then, receive the event from the Iframe.

In the Iframe:

var msger = new CrossMessenger(window.parent, "https://parent.window.domain", {
    cssContent: (data) => {
        var cssElem = document.createElement("style");
        cssElem.innerHTML = data.css;
        document.head.appendChild(cssElem);
    }
})

See the Complete Javascript and Iframes tutorial for more details.

Chemarin

Answer 15

Other answers here seem to use jQuery and CSS links.

This code uses vanilla JavaScript. It creates a new <style> element. It sets the text content of that element to be a string containing the new CSS. And it appends that element directly to the iframe document's head.

var iframe = document.getElementById('the-iframe');
var style = document.createElement('style');
style.textContent =
  '.some-class-name {' +
  '  some-style-name: some-value;' +
  '}' 
;
iframe.contentDocument.head.appendChild(style);

Towe

Answer 16

When you say "doc.open()" it means you can write whatever HTML tag inside the iframe, so you should write all the basic tags for the HTML page and if you want to have a CSS link in your iframe head just write an iframe with CSS link in it. I give you an example:

doc.open();
    
doc.write('<!DOCTYPE html><html><head><meta charset="utf-8"/><meta http-quiv="Content-Type" content="text/html; charset=utf-8"/><title>Print Frame</title><link rel="stylesheet" type="text/css" href="/css/print.css"/></head><body><table id="' + gridId + 'Printable' + '" class="print" >' + out + '</table></body></html>');
    
doc.close();

Tennilletennis

Answer 17

You will not be able to style the contents of the iframe this way. My suggestion would be to use serverside scripting (PHP, ASP, or a Perl script) or find an online service that will convert a feed to JavaScript code. The only other way to do it would be if you can do a serverside include.

Eisegesis

Careful when you say that something cannot be done, when in reality it is just difficult – Concession

Answer 18

Incase if you have access to iframe page and want a different CSS to apply on it only when you load it via iframe on your page, here I found a solution for these kind of things

this works even if iframe is loading a different domain

check about postMessage()

plan is, send the css to iframe as a message like

iframenode.postMessage('h2{color:red;}','*');

* is to send this message irrespective of what domain it is in iframe

and receive the message in iframe and add the received message(CSS) to that document head.

code to add in iframe page

window.addEventListener('message', function(e) {
    if(e.data == 'send_user_details')
    document.head.appendChild('<style>'+e.data+'</style>');
});

Burbank

Answer 19

I think the easiest way is to add another div, in the same place as the iframe, then

make its z-index bigger than the iframe container, so you can easly just style your own div. If you need to click on it, just use pointer-events:none on your own div, so the iframe would be working in case you need to click on it ;)

I hope It will help someone ;)

Scolopendrid

Answer 20

We can insert style tag into iframe.

<style type="text/css" id="cssID">
.className
{
    background-color: red;
}
</style>

<iframe id="iFrameID"></iframe>

<script type="text/javascript">
    $(function () {
        $("#iFrameID").contents().find("head")[0].appendChild(cssID);
        //Or $("#iFrameID").contents().find("head")[0].appendChild($('#cssID')[0]);
    });
</script>

Po

This doesn't work. Seems to insert the style tag correctly but there's no content inside it and no ID. – Enviable

Answer 21

I found another solution to put the style in the main html like this

<style id="iframestyle">
    html {
        color: white;
        background: black;
    }
</style>
<style>
    html {
        color: initial;
        background: initial;
    }
    iframe {
        border: none;
    }
</style>

and then in iframe do this (see the js onload)

<iframe  onload="iframe.document.head.appendChild(ifstyle)" name="log" src="/upgrading.log"></iframe>

and in js

<script>
    ifstyle = document.getElementById('iframestyle')
    iframe = top.frames["log"];
</script>

It may not be the best solution, and it certainly can be improved, but it is another option if you want to keep a "style" tag in parent window

Zurheide

Answer 22

Here, There are two things inside the domain

1. iFrame Section
2. Page Loaded inside the iFrame

So you want to style those two sections as follows,

1. Style for the iFrame Section

It can style using CSS with that respected id or class name. You can just style it in your parent Style sheets also.

#my_iFrame {
    height: 300px;
    width: 100%;
    position:absolute;
    top:0;
    left:0;
    border: 1px black solid;
}

<iframe name='iframe1' id="my_iFrame" src="#" cellspacing="0"></iframe>

2. Style the Page Loaded inside the iFrame

This Styles can be loaded from the parent page with the help of Javascript

var cssFile  = document.createElement("link") 
cssFile.rel  = "stylesheet"; 
cssFile.type = "text/css"; 
cssFile.href = "iFramePage.css"; 

then set that CSS file to the respected iFrame section

//to Load in the Body Part
frames['my_iFrame'].document.body.appendChild(cssFile); 
//to Load in the Head Part
frames['my_iFrame'].document.head.appendChild(cssFile);

---

Here, You can edit the Head Part of the Page inside the iFrame using this way also

var $iFrameHead = $("#my_iFrame").contents().find("head");
$iFrameHead.append(
    $("<link/>", { 
        rel: "stylesheet", 
        href: urlPath, 
        type: "text/css" 
    })
);

Typeset

Answer 23

This is how I'm doing in production. It's worth bearing in mind that if the iframe belongs to other website, it will trigger the CORS error and will not work.

var $iframe = document.querySelector(`iframe`);
var doc = $iframe.contentDocument;

var style = doc.createElement("style");
style.textContent = `*{display:none!important;}`;
doc.head.append(style);

In some cases you may also want to attach a load event to the iframe:

var $iframe =  document.querySelector(`iframe`);

$iframe.addEventListener("load", function() {
    var doc = $iframe.contentDocument;
    var style = doc.createElement("style");
    style.textContent = `*{display:none!important;}`;
    doc.head.append(style);
});

Humor

it doesn't work on me, always get this error $iframe is null. I try use defer and move code to bottom. but still not work – Genovevagenre

@DediAnanto if the iframe is coming from a different URL then it won't work. Injecting CSS on cross origin iframes is not possible. In this case you may want to try to extract the iframe's content, something like this, but there is not a guarantee it will work either. – Humor

ah I found the issue. it is because I use pdf on iframe. it works when iframe has html as content, but if I use pdf on iframe, it got error Permission denied to access property "document" on cross-origin object . any suggestion for this? or I need to create new question – Genovevagenre

Answer 24

var link1 = document.createElement('link');
    link1.type = 'text/css';
    link1.rel = 'stylesheet';
    link1.href = "../../assets/css/normalize.css";
window.frames['richTextField'].document.body.appendChild(link1);

Multi

I have checked this answer many times what is richTextField here ? – Byrle

it's the iframe name – Multi

I didn't tried, but I guess It won't because its against the sandbox – Multi

Answer 25

There is a wonderful script that replaces a node with an iframe version of itself. CodePen Demo

Usage Examples:

// Single node
var component = document.querySelector('.component');
var iframe = iframify(component);

// Collection of nodes
var components = document.querySelectorAll('.component');
var iframes = Array.prototype.map.call(components, function (component) {
  return iframify(component, {});
});
    
// With options
var component = document.querySelector('.component');
var iframe = iframify(component, {
  headExtra: '<style>.component { color: red; }</style>',
  metaViewport: '<meta name="viewport" content="width=device-width">'
});

Revival

Why would you want to do that?! – Firelock

Answer 26

As an alternative, you can use CSS-in-JS technology, like below lib:

https://github.com/cssobj/cssobj

It can inject JS object as CSS to iframe, dynamically

Try

Answer 27

This is just a concept, but don't implement this without security checks and filtering! Otherwise script could hack your site!

Answer: if you control target site, you can setup the receiver script like:

1) set the iframe link with style parameter, like:

http://your_site.com/target.php?color=red

(the last phrase is a{color:red} encoded by urlencode function.

2) set the receiver page target.php like this:

<head>
..........
$col = FILTER_VAR(SANITIZE_STRING, $_GET['color']);
<style>.xyz{color: <?php echo (in_array( $col, ['red','yellow','green'])?  $col : "black") ;?> } </style>
..........

Cochrane

Warning: this is injection at its finest. – Entozoic

yap, do NOT do this, except you want a load of pen-test bots and script kiddies on your server =)... – Jarid

I've updated answer now, with added security warning – Cochrane

Answer 28

Well, I have followed these steps:

1. Div with a class to hold iframe
2. Add iframe to the div.
3. In CSS file,

divClass { width: 500px; height: 500px; }
divClass iframe { width: 100%; height: 100%; }

This works in IE 6. Should work in other browsers, do check!

Cowgill

need to control div inside of iframe, this does not – Pheni