<div id="app">
  <modal
    v-if="showModal"
    @close="showModal = false"
  ></modal>
  <button
    class="button"
    @click="showModal = true"
  >
    Show Modal
  </button>
</div>

<script type="text/x-template" id="modal">
  <transition
    name="fade"
    @after-enter="showContent = true"
  >
    <div
      class="modal"
      @click="showContent = false"
    >
      <transition
        name="fade"
        @after-leave="$emit('close')"
      >
        <div
          v-if="showContent"
          class="content"
          @click.stop
        >
          Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quisquam, placeat, unde! Architecto laboriosam ducimus atque cum dolore doloribus obcaecati vero. Minus porro sapiente unde fuga incidunt quidem necessitatibus mollitia libero?
        </div>
      </transition>
    </div>
  </transition>
</script>
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  height: 100vh;
  width: 100vw;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.button {
  border-radius: 2px;
  background: #D55672;
  border: none;
  padding: 10px;
  font-size: 14px;
  font-weight: bold;
  cursor: pointer;
  color: #FFF;
  outline: none;
  transition: 0.1s background;
}

.button:hover {
  background: #AA445B;
}

.modal {
  position: absolute;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0,0,0,0.6)
}

.content {
  position: absolute;
  top: 50%;
  left: 50%;
  width: calc(100% - 20px);
  max-width: 500px;
  transform: translate(-50%, -50%);
  background: #FFF;
  border-radius: 3px;
  padding: 20px;
  line-height: 1.5;
  font-size: 18px;
  color: #444;
  box-shadow: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
}

.fade-enter, .fade-leave-to {
  opacity: 0;
}

.fade-enter-active, .fade-leave-active {
  transition: 0.2s opacity ease-out;
}
Vue.component('modal', {
  template: '#modal',
  data () {
    return {
      showContent: false
    }
  }
})

new Vue({
  el: '#app',
  data () {
    return {
      showModal: false
    }
  }
})

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.4/vue.min.js