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HTML

CSS

CSS Base

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JavaScript

Babel includes JSX processing.

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HTML

              
                <button class="prepend">Prepend list item</button>
<button class="append">Append list item</button>
<button class="removeFirst">Remove first item</button>
<button class="removeLast">Remove last item</button>

<ul>
  <li>Hello world!</li>
</ul>
              
            
!

CSS

              
                button {
  font-size: 1em;
  margin-top: 1em;
  margin-left: 1em;
  padding: 0.5em 0.75em;
  + button {
    margin-left: 0.5em;
  }
}

              
            
!

JS

              
                let prepend = document.querySelector('.prepend')
let append = document.querySelector('.append')
let removeFirst = document.querySelector('.removeFirst')
let removeLast = document.querySelector('.removeLast')
let list = document.querySelector('ul')

function createLi () {
  let li = document.createElement('li')
  li.innerHTML = 'Hello again, world!'
  return li
}

// Prepend
prepend.addEventListener('click', e => list.prepend(createLi()))

// Append
append.addEventListener('click', e => list.append(createLi()))

// Remove First
removeFirst.addEventListener('click', e => {
  if (list.children.length) {
    let firstNode = list.children[0]
    list.removeChild(firstNode)
  }
})    

// Remove Last
removeLast.addEventListener('click', e => {
  if (list.children.length) {
    let lastNode = list.children[list.children.length - 1]
    console.log(lastNode)
    list.removeChild(lastNode)
  }
})   
              
            
!
999px

Console