test_hal_gridsome/src/layouts/Default.vue

<template>
  <div class="layout">
    <header class="header">
      <strong>
        <g-link to="/">{{ $static.metaData.siteName }}</g-link>
      </strong>
      <nav class="nav">
        <g-link class="nav__link" to="/">Home</g-link>
        <g-link class="nav__link" to="/article">Article</g-link>
      </nav>
    </header>
    <main>
      <slot/>
    </main>
    <footer>
      <p class="home-links">
        <a href="https://gridsome.org/docs" target="_blank" rel="noopener">Gridsome Docs</a>
        <a href="https://github.com/gridsome/gridsome" target="_blank" rel="noopener">GitHub</a>
      </p>
    </footer>
  </div>
</template>

<static-query>
query {
  metaData {
    siteName
  }
}
</static-query>

<style>
html,body{
  height:100%;
}
body {
  font-family: "Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  margin:0;
  padding:0;
  line-height: 1.5;
  display:flex;
  flex-direction:column;
  justify-content:flex-start;
  align-items:center;
}

.layout {
  max-width: 760px;
  padding-left: 20px;
  padding-right: 20px;
  height:100%;
  display:flex;
  flex-direction:column;
}

main{
  height:100%;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  height: 80px;
}

.nav__link {
  margin-left: 20px;
}
</style>