Create a countdown timer using VueJS 2

CountdownTimer.vue

<template>
  <div>
    <div class="the-countdown">
      <ul>
        <li>
          <div>
            <span>Days</span>
            {{ days | two_digits }}
          </div>
        </li>
        <li>
          <div>
            <span>Hours</span>
            {{ hours | two_digits }}
          </div>
        </li>
        <li>
          <div>
            <span>Minutes</span>
            {{ minutes | two_digits }}
          </div>
        </li>
        <li>
          <div>
            <span>Seconds</span>
            {{ seconds | two_digits }}
          </div>
        </li>
      </ul>
    </div>
  </div>
</template>

<script>
export default {
  props: ['date'],
  data() {
    return {
      now: Math.trunc((new Date().getTime() / 1000))
    }
  },
  computed: {
    days() {
      let date = Math.trunc(Date.parse(this.date) / 1000)
      return Math.trunc((date - this.now) / 60 / 60 / 24)
    },
    hours() {
      let date = Math.trunc(Date.parse(this.date) / 1000)
      return Math.trunc((date - this.now) / 60 / 60) % 24
    },
    minutes() {
      let date = Math.trunc(Date.parse(this.date) / 1000)
      return Math.trunc((date - this.now) / 60) % 60
    },
    seconds() {
      let date = Math.trunc(Date.parse(this.date) / 1000)
      return (date - this.now) % 60
    }
  },
  mounted() {
    window.setInterval(() => {
      this.now = Math.trunc((new Date().getTime() / 1000))
    }, 1000)
  },
}
</script>

<style scoped>
  .the-countdown {
    width: 50%;
    margin: 10px auto 0 auto;
    font-size: 14px;
    line-height: 20px;
    text-align: center;
  }

  .the-countdown strong{
    text-transform: uppercase;
    letter-spacing: 1px;
  }

  .the-countdown ul{
    margin: 10px -10px -10px -10px;
    overflow: auto;
  }

  .the-countdown ul li{
    float: left;
    position: relative;
    padding: 10px;
    width: 25%;
    text-align: center;
    box-sizing: border-box;
    font-size: 60px;
    line-height: 60px;
    font-weight: 100;
  }

  .the-countdown ul li:after{
    content: ':';
    position: absolute;
    top: 50%;
    margin: -25px 0 0 0;
    right: -5px;
    color: #98A2AB;
  }

  .the-countdown ul li:last-child:after{
    display: none;
  }

  .the-countdown ul li div{
    background: #EEE;
    padding: 20px;
    overflow: hidden;
  }

  .the-countdown ul li:first-child div{
    border-radius: 10px 0 0 10px;
  }

  .the-countdown ul li:last-child div{
    border-radius: 0 10px 10px 0;
  }

  .the-countdown ul li span{
    display: block;
    font-weight: bold;
    color: #FFF;
    margin: -20px -20px 20px -20px;
    background: #98A2AB;
    font-size: 12px;
    line-height: 12px;
    padding: 10px;
  }

</style>

Index.vue

<template>
  <CountdownTimer date="2019/02/20"></CountdownTimer>
</template>

<script>
import CountdownTimer from './shared/CountdownTimer.vue'

export default {
  components: {
    CountdownTimer
  }
}

</script>

main.js

// Create a filter for 2 digits
Vue.filter('two_digits', (value) => {
	if (value.toString().length <= 1) return '0' + value.toString()
	return value.toString()
})

A simple gist for creating a countdown timer using VueJS 2