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                <div id="root"></div>


                $bg    = #FFCDD2
$text  = #F5F5F5
$black = #191919

* { box-sizing: border-box }

body {
  font-family: 'Space Mono', sans-serif
  background-color: $bg

.clock {
  color: $text
  width: 250px
  height: 70px
  position: absolute
  top: 50%
  left: 50%
  transform: translate(-50%, -50%)
  border-radius: 4px
  background-color: $black
  box-shadow: 0 20px 40px 0 rgba(0, 0, 0, .35)

  .time {
    position: absolute
    top: 50%
    left: 50%
    transform: translate(-50%, -50%)
    display: block
    font-size: 1.4em
    letter-spacing: 0.04em



                class Clock extends React.Component {
  constructor(props) {
    this.state = {
      time: new Date()
  componentDidMount() {
    this.timerID = setInterval(() => {
    }, 1000)

  componentWillUnmount() {
  ticTac() {
    this.setState({ time: new Date() })
  getTime() {
    const options = {
      hour: 'numeric',
      minute: 'numeric',
      second: 'numeric'

    return this.state.time.toLocaleTimeString('pt-BR', options)
  render() {
    return (
      <div className='clock'>
        <span className='time'>{this.getTime()}</span>

ReactDOM.render(<Clock />, document.getElementById('root'))