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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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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.

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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-.

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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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HTML 

              
                <div class="container-text">
  <h1>::marker</h1>
  <p>
    The new <code>::marker</code> pseudo element lets us take control of these little things, &#8226;, aka bullets! But sometimes depending on the list you use they could also be numbers, roman numerals and even letters.
  </p>
  <p>
    Before this brand new revelation we would have to invent new powerful hacks, (albeit....multi-line CSS hacks) to customise the bullet in several ways.
  </p>
  <p>
    One of the most prominent hacks for this was to use the <code>::before</code> pseudo element on the list item itself, and set the <code>content</code> property to override the default bullet along with some other CSS properties. Now with the advancements in CSS lately, we can now use <code>::marker</code> pseudo-element to target the marker box of the list item, (check out the docs here: <a href="https://developer.mozilla.org/en-US/docs/Web/CSS/::marker" target=_blank>Mozilla</a>).
  </p>
</div>

<div class="container-list">
  <p>Below you will find two prominent examples of it in action. An unordered list with the default bullets replaced with emoji icons, and an ordered list with the default numerals replaced with an SVG. 😁</p>
  <p>Unordered List with emojis:</p>
  <ul>
    <li class="ul-marker">Happy</li>
    <li class="ul-marker">Cool</li>
    <li class="ul-marker">Yawn</li>
    <li class="ul-marker">Sad</li>
    <li class="ul-marker">Angry</li>
  </ul>
  
<!--   <p>Ordered List with SVGs:</p>
  <p>Of course it probably isn't a good idea to replace the markers in an ordered list, unless you are replacing with a similar marker to denote the order of the items!</p>
  <p>Below SVG found <a href="https://www.svgrepo.com/">here</a> at SVG Repo.</p>
  <ol>
    <li class="ol-marker">HTML</li>
    <li class="ol-marker">CSS</li>
    <li class="ol-marker">Python</li>
  </ol> -->
</div>

<div class="container-list-2">
  <p>
    But what about description lists and their children (Terms & Definitions)?
  </p>
  <p>
    Don't worry about it, by setting the display of the Description List Term & Definition elements to <code>list-item</code>, we can then use the <code>::marker</code> pseudo-element to add custom markers to this type of list too.
  </p>
  <dl>
    <dt>Halloween</dt>
    <dd>Is the best holiday of the year. All of the spoops!</dd>
  </dl>
</div>

<div class="container-details">
  <p>
    We can also customise the "twisty" icon that is the default marker of the <code>details</code> element child, called the <code>summary</code> element.
  </p>
  <p>
    Below we have a <code>details</code> element that on click changes the current marker. Pretty simple how to do this and that could be something for another time, but again it's another list marker that we can control. 
  </p>
  
  <details>
    <summary></summary>
    ...why?
  </details>
</div>
!

CSS 

              
                body {
  background: #3f3f3f;
  color: #f5f5f5;
  text-align: center;
}

code {
  background-color: #666666;
  padding: 3px;
  border: 1px solid;
  border-radius: 5px;
}

a {
  color: #27dcb0;
}

p {
  margin-bottom: 0;
  line-height: 1.5rem;
  padding: 0 1rem;
}

.container-text {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  margin: 2rem 0;
}

h1::after {
  content: '';
  display: block;
  height: 1px;
  background: #f5f5f5;
}

.container-list {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

ul {
  display: flex;
  gap: 3rem;
}

.ul-marker {
  padding-left: 1ch;
  margin: 1rem 0;
  
  &:nth-child(1)::marker {
    content: '😄';
  }
  
  &:nth-child(2)::marker {
    content: '😎';
  }
  
  &:nth-child(3)::marker {
    content: '🥱';
  }
  
  &:nth-child(4)::marker {
    content: '😢';
  }
  
  &:nth-child(5)::marker {
    content: '😤';
  }
}

// .ol-marker {
//   padding-left: 1ch;
//   margin: 1rem 0;
  
//   &::marker {
//     content: url("https://www.svgrepo.com/show/317386/forest-burn.svg");
//   }
// }

.container-list-2 {
  display: flex;
  flex-direction: column;
  align-items: center;
}

dt {
  display: list-item;
  padding-inline-start: 2ch;
  margin-bottom: 1rem;
  text-decoration: underline;
  text-align: left;
  
  &::marker {
    content: '👻';
    font-size: 2rem;
  }
}

dd {
  display: list-item;
  padding-left: 1ch;
  
  &::marker {
    content: '💀';
  }
}

.container-details {
  display: flex;
  flex-direction: column;
  margin-bottom: 5rem;
}

details[open] {
  summary::after {
    content: 'you touched it...';
  }
  summary::marker {
    content: '🤢';
  }
}

summary {
  margin: 1rem 0;
  
  &::after {
    content: 'touch the poop...'
  }
  
  &::marker {
    content: '💩';
  }
}
!

JS
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