How can another Toast appear when a vue project is submitted when a modal exists?

Project uses mint-ui, to ask how to click the button in modal, toast (that is, another pop-up box) appears.
now toast appears, but under modal
there will be a modal page

<template>
  <div id="app">
    <button @click="showModal">button</button>
    <modal></modal>
  </div>
</template>

<script>
import Modal from "@components/Modal/index"
export default {
  name: "App",
  components: {
    Modal,
  },
  methods: {
    showModal () {
      alert("modal")
    }
  }
}
</script>

modal Code

<template>
  <transition name="modal">
    <div class="modal-mask">
      <div class="modal-wrapper">
        <div class="modal-container">
          <div class="modal-body">
            <slot name="body">
              <h4></h4>
              <input type="text" name="name" v-model="name">
              <div class="btn-group">
                  <button @click="$emit("close")"></button>
                  <button @click="submit"></button>
              </div>
            </slot>
          </div>
        </div>
      </div>
    </div>
  </transition>
</template>
<style lang="stylus" scoped>
@import "~@styles/varibles.styl"
.modal-mask {
  position: fixed;
  z-index: 9998;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, .5);
  display: flex
  justify-content center
  transition: opacity .3s ease;
}

.modal-wrapper {
    width 5.42rem
    height 3.9rem
    border-radius 0.06rem
    background white
    margin-top 3.62rem
}

.modal-container {
    padding 0.31rem 0.47rem
}

.modal-header h3 {
  margin-top: 0;
  color: -sharp42b983;
}

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

.modal-enter {
  opacity: 0;
}

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

.modal-enter .modal-container,
.modal-leave-active .modal-container {
  -webkit-transform: scale(1.1);
  transform: scale(1.1);
}

.modal-body {
    h4{
        font-weight: $titleWeight
        margin-bottom 0.45rem
    }
    input{
        width 4rem
        height 0.42rem
        border 1px solid -sharpe2e2e2
        border-radius 0.1rem
        padding 0.19rem 0.24rem
        margin-bottom 0.85rem
    }
    div.btn-group{
        display flex
        justify-content space-between
        button{
            width 2.03rem
            height 0.7rem
            border-radius 0.35rem
            font-weight $titleWeight
            color white
            letter-spacing 0.02rem
            &:last-child{
                background $rose
            }
        }
    }
}
</style>