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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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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-.

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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 

              
                <h1>For</h1>
<div class="pokemon">
  <h2>7세대 돌팀</h2>
</div>

<h1>For in</h1>
<h2>주어진 배열에서 4의 배수만 찾아보자! </h2>
<div class="for_in"></div>

<h1>For of</h1>
<h2>주어진 배열에서 3의 배수만 찾아보자! </h2>
<div class="for_of"></div>
!

CSS 

              
                * {
  margin: 0;
  padding: 0;
}

div {
  margin-bottom:10px;
}

p {
  font-size:14pt;
  color:#999999;
}
!

JS 

              
                let pokemon_div = document.querySelector('.pokemon')
let for_in_div = document.querySelector('.for_in')
let for_of_div = document.querySelector('.for_of')
//div 드가자

let pokemon = ['김부추씨','김상추씨','김배추씨','김양상추씨','김양배추씨','김후추씨']

for (let i = 0;i < pokemon.length;i++) {
  let p_tag = document.createElement('p')
  p_tag.innerText = pokemon[i]
  pokemon_div.appendChild(p_tag)
}
//for

let num_list = [806, 26, 607, 601, 752, 504, 485, 162, 885, 361, 309, 480, 401, 313, 771, 141, 9, 526, 390, 237]

for (let i in num_list) {
  let p_tag = document.createElement('p')
  if (num_list[i] % 4 == 0) {
    p_tag.innerText = num_list[i]
    for_in_div.appendChild(p_tag)
  }
}
// for in

for (let i of num_list) {
  let p_tag = document.createElement('p')
  if (i % 3 == 0) {
    p_tag.innerText = i
    for_of_div.appendChild(p_tag)
  }
}
//for of
!
999px

Console