CODE EXAMPLE FOR JAVASCRIPT

vue js override component css

// in CompA (the parent)

<template>
  ...
  <!-- Vue provides built-in class and style props for all comps -->
  <compb class="compb"></compb>  
</template>

<script>
  ...
</script>

<style lang="scss">
  #app .compb .compb-header { 
    color: red; 
  }
</style>

<style lang="scss" scoped>
  ...
</style>