index.html

<template>
  <main class="hero-full">
    <div class="text-center text-6xl font-bold text-white hero-body">
      <router-view />
      <Footer />
    </div>
  </main>
</template>

tailwind-fullheight-width.css

main {
  display: block;
}
.hero-full {
  @apply w-full h-full flex items-center justify-center flex-wrap px-4 py-10 text-center text-gray-700 dark:text-gray-200;
}

.hero-foot {
  @apply flex-1 items-center justify-items-center flex;
  flex-basis: 100%;
}

.hero-body {
  @apply flex-1 flex-grow flex-shrink-0 px-4;
}