<template lang="pug">
b-modal.simple-modal(
  :active="showUnauthModal"
  width="720"
  scroll= "keep"
  @close="toggleModal"
)
...
 button.is-primary(@click="toggleModal")
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</template>

state: {
    showUnauthModal: false,
  },

toggleModal() {
  this.showUnauthModal = false;
},