<h3 class="bark">Bark Bark</h3> <input type="checkBox" class="title">Hear a dog</input>
CSS：
.bark{ visibility: hidden } input[type="checkBox"]:checked { visibility: visible }
.bark{ visibility: hidden } input[type="checkBox"]:checked + h3.bark { visibility: visible }
<input type="checkBox" class="title">Hear a dog</input> <h3 class="bark">Bark Bark</h3>
