text marker  

html記載

<h1 class="markerblue">テキストテキスト</h1>

css記載

.marker{
  background: linear-gradient(transparent 60%, #ffff66 60%);    /*黄色*/
  }
  .markerblue{
  background: linear-gradient(transparent 60%, #c3e9ff 60%);   /*水色*/
  }