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HTML

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About the <head>

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Insecure Resource

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CSS

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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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JavaScript

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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="window">
  <aside>
    <nav>
      <ul>
        <li></li>
        <li></li>
        <li></li>
      </ul>    
    </nav>
    <div class="aside-content">
      <details open>
        <summary>Favorite</summary>
        <ul>
          <li>Recent</li>
          <li>Yexan</li>
          <li>Images</li>
          <li>Documents</li>
          <li>Apps</li>
          <li class="active">Desktop</li>
          <li>Downloads</li>
        </ul>
      </details>
      <details open>
        <summary>Connected</summary>
        <ul>
          <li>Network</li>
          <li>Hard Drive</li>
          <li>Hard Drive</li>
        </ul>
      </details>
    </div>
  </aside>
  <main>
    <nav>
      Desktop
    </nav>
    <div class="main-content">
      
    </div>
  </main>
</div>
!

CSS 

              
                .window
  position: fixed
  top: 70px
  left: 120px
  width: 650px
  height: 350px
  display: grid
  grid-template-columns: 200px 1fr
  border-radius: 10px
  box-shadow: 5px 5px 25px -2px rgba(0,0,0,.4) 
  overflow: auto
    
aside
  position: relative
  padding: 0
  margin: 0
  backdrop-filter: blur(25px)
  
  nav
    position: absolute
    top: 0
    left: 0
    right: 0
    padding: 20px 15px
    z-index: 2
    cursor: move
    
    ul
      display: flex
      flex-direction: row
      align-items: center
      justify-content: flex-start
    
    li
      width: 13px
      height: 13px
      padding: 0
      border-radius: 10px
      cursor: pointer
      
      &:before
        background: none
    
      & + li
        margin-left: 10px
        
      &:nth-child(1)
        background: #E53935
      
      &:nth-child(2)
        background: #FFCA28
      
      &:nth-child(3)
        background: #8BC34A
  
  .aside-content
    position: absolute
    top: 50px
    bottom: 0
    left: 0
    right: 0
    padding: 0px 15px 15px
    overflow: auto
    
  details
    & + details
      margin-top: 15px
  
  summary
    margin-bottom: 2px
    font-size: .85em
    font-weight: bold
    color: rgba(0, 0, 0, .7)
    cursor: pointer
  
  ul
    margin: 0
    padding: 0 0 0 5px
    list-style: none
  
  li
    position: relative
    padding: 5px 0 5px 35px
    color: rgba(255, 255, 255, .8)
    border-radius: 5px
    cursor: pointer
    
    &.active
      background: rgba(255, 255, 255, .1)
      
    &:before
      content: ''
      position: absolute
      top: 4px
      left: 8px
      width: 20px
      height: 20px
      background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 298.757 298.757'%3E%3Cpath fill='%2357F' d='M291.701,119.091h-39.95v-29.61c0-3.893-3.156-7.05-7.05-7.05h-95.549l-16.896-35.955 c-1.162-2.472-3.648-4.051-6.381-4.051H7.05c-3.893,0-7.05,3.157-7.05,7.05v199.806c0,3.846,3.135,7.051,7.054,7.051 c0.004,0,0.008-0.001,0.012-0.001h237.635c2.923,0,5.543-1.805,6.587-4.536l47-123.14 C300.048,124.044,296.635,119.091,291.701,119.091z M14.1,56.526h107.299l16.896,35.955c1.162,2.472,3.648,4.051,6.381,4.051 h92.975v22.56H54.05c-2.923,0-5.544,1.805-6.587,4.536L14.1,211.04V56.526z M239.846,242.231H17.287l41.618-109.04 c10.158,0,212.404,0,222.559,0L239.846,242.231z'/%3E%3C/svg%3E") no-repeat
      background-size: 90%

main
  position: relative
  padding: 0
  margin: 0
  
  nav
    position: absolute
    top: 0
    left: 0
    right: 0
    display: flex
    flex-direction: row
    align-items: center
    padding: 0 20px
    height: 50px
    color: rgba(255, 255, 255, .8)
    background: rgba(20, 20, 20, 1)
    z-index: 2
    cursor: move
    
.main-content
  position: absolute
  top: 50px
  bottom: 0
  left: 0
  right: 0
  padding: 0px 15px 15px
  background: rgba(10, 10, 10, .95)
  overflow: auto

  
body
  height: 100vh
  margin: 0
  padding: 0
  font-family: Arial
  background-image: url('https://images.unsplash.com/photo-1653579636217-0a062a1390ed?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=2940&q=80')
  background-size: cover
  background-position: center
  background-repeat: no-repeat
!

JS 

              
                let pos1 = 0
let pos2 = 0
let pos3 = 0
let pos4 = 0

// Draggalbe window element
const win = document.querySelector('.window')

const dragMouseDown = (evt: MouseEvent) => {
  evt = evt || window.event
  evt.preventDefault()
  pos3 = evt.clientX
  pos4 = evt.clientY
  document.onmouseup = closeDragElement
  document.onmousemove = elementDrag
}

const elementDrag = (evt: MouseEvent) => {
  evt = evt || window.event
  evt.preventDefault()
  pos1 = pos3 - evt.clientX
  pos2 = pos4 - evt.clientY
  pos3 = evt.clientX
  pos4 = evt.clientY
  win.style.top = (win.offsetTop - pos2) + 'px'
  win.style.left = (win.offsetLeft - pos1) + 'px'
}

const closeDragElement = () => {
  document.onmouseup = null
  document.onmousemove = null
} 


// Grabbed element allowed to move the window
const asideNav = document.querySelector('.window aside nav')
const mainNav = document.querySelector('.window main nav')

asideNav.onmousedown = dragMouseDown
mainNav.onmousedown = dragMouseDown
!
999px

Console