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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

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HTML 

              
                <article>
		<header>
			<h1>
				Noframe.js 
			</h1>
			<p>This page is a demo of a <a href="https://github.com/yowainwright/reframe.js">Noframe.js</a> - a very basic lightweight plugin that makes iframes or embedded content responsive.</p>
      <p>More deeply, this means that it makes elements scale at a fixed ratio.</p>
		</header>
		<div>
			<iframe width="560" height="315" src="https://www.youtube.com/embed/6FQsIfE7sZM" frameborder="0" allowfullscreen></iframe>
      </div>
			<p>This is an <code>iframe</code> that contains a video.</p>
		<footer>
			<p>~Thanks</p>
		</footer>
	</article>
!

CSS 

              
                figure,p{margin:1rem 0}figcaption{margin:.5rem 0;text-align:center}article{margin:1rem;width:100%;}@media screen and (min-width:768px){article{margin:1rem auto;max-width:700px}}footer p,h1{text-align:center}footer,h1{margin:2rem auto}
!

JS 

              
                /**
  reframe.js - Reframe.js: responsive iframes for embedded content
  @version v4.0.0
  @link https://github.com/yowainwright/reframe.ts#readme
  @author Jeff Wainwright <yowainwright@gmail.com> (http://jeffry.in)
  @license MIT
**/
(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
  typeof define === 'function' && define.amd ? define(factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, global.noframe = factory());
})(this, (function () { 'use strict';

  /* noframe.js () 🖼
    -------------
    takes 2 arguments:
    => target: targeted <element>
    => container: optional targeted <parent> of targeted <element>
    -------------
    defines the height/width ratio of the targeted <element>
    based on the targeted <parent> width
  */
  function noframe(target, container) {
      var frames = typeof target === 'string' ? document.querySelectorAll(target) : target;
      if (!('length' in frames))
          frames = [frames];
      for (var i = 0; i < frames.length; i += 1) {
          var frame = frames[i];
          var isContainerElement = typeof container !== 'undefined' && document.querySelector(container);
          var parent_1 = isContainerElement ? document.querySelector(container) : frame.parentElement;
          var h = frame.offsetHeight;
          var w = frame.offsetWidth;
          var styles = frame.style;
          // => If a targeted <container> element is defined
          if (isContainerElement) {
              // gets/sets the height/width ratio
              var maxW = window.getComputedStyle(parent_1, null).getPropertyValue('max-width');
              styles.width = '100%';
              // calc is needed here b/c the maxW measurement type is unknown
              styles.maxHeight = "calc(".concat(maxW, " * ").concat(h, " / ").concat(w, ")");
          }
          else {
              // gets/sets the height/width ratio
              // => if a targeted <element> closest parent <element> is NOT defined
              styles.display = 'block';
              styles.marginLeft = 'auto';
              styles.marginRight = 'auto';
              var fullW = w > parent_1.offsetWidth ? parent_1.offsetWidth : w;
              var maxH = w > parent_1.offsetWidth ? (fullW * h) / w : w * (h / w);
              // if targeted <element> width is > than it's parent <element>
              // => set the targeted <element> maxheight/fullwidth to it's parent <element>
              styles.maxHeight = "".concat(maxH, "px");
              styles.width = "".concat(fullW, "px");
          }
          // set a calculated height of the targeted <element>
          var cssHeight = (100 * h) / w; // eslint-disable-line no-mixed-operators
          styles.height = "".concat(cssHeight, "vw");
          styles.maxWidth = '100%';
      }
  }

  return noframe;

}));

noframe('iframe');
!
999px

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