core/packages/vue/examples/transition/modal.html

<script src="../../dist/vue.global.js"></script>

<!-- template for the modal component -->
<script type="text/x-template" id="modal-template">
  <transition name="modal">
    <div v-if="show" class="modal-mask">
      <div class="modal-wrapper">
        <div class="modal-container">

          <div class="modal-header">
            <slot name="header">
              default header
            </slot>
          </div>

          <div class="modal-body">
            <slot name="body">
              default body
            </slot>
          </div>

          <div class="modal-footer">
            <slot name="footer">
              default footer
              <button class="modal-default-button" @click="$emit('close')">
                OK
              </button>
            </slot>
          </div>
        </div>
      </div>
    </div>
  </transition>
</script>
<script>
  const Modal = {
    template: '#modal-template',
    props: ['show'],
  }
</script>

<!-- modal container that lives outside of app root -->
<div id="modal-container"></div>

<!-- app -->
<div id="app">
  <button id="show-modal" @click="showModal = true">Show Modal</button>
  <teleport to="#modal-container">
    <!-- use the modal component, pass in the prop -->
    <modal :show="showModal" @close="showModal = false">
      <template #header>
        <h3>custom header</h3>
      </template>
    </modal>
  </teleport>
</div>

<script>
  Vue.createApp({
    components: { Modal },
    data: () => ({
      showModal: false,
    }),
  }).mount('#app')
</script>

<style>
  .modal-mask {
    position: fixed;
    z-index: 9998;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: table;
    transition: opacity 0.3s ease;
  }

  .modal-wrapper {
    display: table-cell;
    vertical-align: middle;
  }

  .modal-container {
    width: 300px;
    margin: 0px auto;
    padding: 20px 30px;
    background-color: #fff;
    border-radius: 2px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.33);
    transition: all 0.3s ease;
    font-family: Helvetica, Arial, sans-serif;
  }

  .modal-header h3 {
    margin-top: 0;
    color: #42b983;
  }

  .modal-body {
    margin: 20px 0;
  }

  .modal-default-button {
    float: right;
  }

  /*
 * The following styles are auto-applied to elements with
 * transition="modal" when their visibility is toggled
 * by Vue.js.
 *
 * You can easily play with the modal transition by editing
 * these styles.
 */

  .modal-enter-from {
    opacity: 0;
  }

  .modal-leave-to {
    opacity: 0;
  }

  .modal-enter-from .modal-container,
  .modal-leave-to .modal-container {
    -webkit-transform: scale(1.1);
    transform: scale(1.1);
  }
</style>