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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

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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

Add Packages

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 

              
                <label for="option" class="c-custom-checkbox">
  <!--  length of the path is 270px -->
  <input type="checkbox" id="option"/>
  <svg viewBox="0 0 60 40" aria-hidden="true" focusable="false"><path d="M21,2 C13.4580219,4.16027394 1.62349378,18.3117469 3,19 C9.03653312,22.0182666 25.2482171,10.3758914 30,8 C32.9363621,6.53181896 41.321398,1.67860195 39,4 C36.1186011,6.8813989 3.11316157,27.1131616 5,29 C10.3223659,34.3223659 30.6434647,19.7426141 35,18 C41.2281047,15.5087581 46.3445303,13.6554697 46,14 C42.8258073,17.1741927 36.9154967,19.650702 33,22 C30.3136243,23.6118254 17,31.162498 17,34 C17,40.4724865 54,12.4064021 54,17 C54,23.7416728 34,27.2286213 34,37" stroke-width="4" fill="none" stroke-dasharray="270" stroke-dashoffset="270" ></path></svg>
  Add an accessibility statement
</label>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Indie+Flower);

body {
  background-color: HSL(250, 22%, 30%);
  padding: 10vw;
  font-size: 2em;
  line-height: 1.6;
}

.c-custom-checkbox {
  display: block;
  position: relative;
  cursor: pointer;
  color: #eee;
  font-family: Indie Flower;
}

.c-custom-checkbox svg { 
  display: inline-block;
  vertical-align: middle;
  margin-bottom: .2em;
  width: 1em;
  height: 1em;
  border: 2px solid currentColor;
}


.c-custom-checkbox input[type="checkbox"] {
  opacity: 0;
  width: 1em;
  height: 1em;
  position: absolute;
  left: .5em;
  top: .4em;
}

.c-custom-checkbox svg path {
  transition: stroke-dashoffset .4s linear;
}


.c-custom-checkbox input[type="checkbox"]:checked + svg path {
  stroke-dashoffset: 0;
  stroke: currentColor;
}

.c-custom-checkbox input[type="checkbox"] + svg path {
  stroke: #eee;
}

.c-custom-checkbox input[type="checkbox"]:checked + label {
  text-decoration: line-through;
}

.c-custom-checkbox input[type="checkbox"]:focus + svg {
  outline: 2px solid gold;
  outline-offset: 4px;
}


.c-custom-checkbox input[type="checkbox"]:focus:not(:focus-visible) + svg {
  outline: none;
}
!

JS
!
999px

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