A simple example of a Vue single file component

SimpleComponent.vue

<template>
  <div id="app">
    <ul>
      <li v-for='number in numbers' :key='number'>{{ number }}</li>
    </ul>
    <form @submit.prevent='addNumber'>
      <input type='text' v-model='newNumber'>
      <button type='submit'>Add another number</button>
    </form>
  </div>
</template>

<script>
export default {
  name: 'app',
  methods: {
    addNumber() {
      const num = +this.newNumber;
      if (typeof num === 'number' && !isNaN(num)) {
        this.numbers.push(num);
      }
    }
  },
  data() {
    return {
      newNumber: null,
      numbers: [1, 23, 52, 46]
    };
  }
}
</script>

<style lang="scss">
ul {
  padding: 0;
  li {
    list-style-type: none;
    color: blue;
  }
}
</style>