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                <span is="type-async" id="type-text">...</span>
<span class="blinking-cursor">_</span>



                @import url("")

  padding: 0 10%
  background-color: #111
  color: #FFF
  font-family: "Open Sans", sans-serif
  font-size: 2em
  line-height: 100vh
  white-space: nowrap

  user-select: none
  animation: blink 1s steps(2, start) infinite
  @keyframes blink
      visibility: hidden



                async function init () {
  const node = document.querySelector("#type-text")
  await sleep(1000)
  node.innerText = ""
  await node.type('Hello, ')
  while (true) {
    await node.type('CodePen!')
    await sleep(2000)
    await node.delete('CodePen!')
    await node.type('World!')
    await sleep(2000)
    await node.delete('World!')

// Source code 🚩

const sleep = time => new Promise(resolve => setTimeout(resolve, time))

class TypeAsync extends HTMLSpanElement {
  get typeInterval () {
    const randomMs = 100 * Math.random()
    return randomMs < 50 ? 10 : randomMs
  async type (text) {
    for (let character of text) {
      this.innerText += character
      await sleep(this.typeInterval)
  async delete (text) {
    for (let character of text) {
      this.innerText = this.innerText.slice(0, this.innerText.length -1)
      await sleep(this.typeInterval)

customElements.define('type-async', TypeAsync, { extends: 'span' })