body {
  background-color: black;
  color: white;
  line-height: 1.6;
  font-family: "Noto Sans Japanese", "Helvetica Neue", Helvetica, sans-serif;
  font-weight: 300;
}

header {
  text-align: center;
}

header .logo {
  max-width: 640px;
  width: 100%;
  height: auto;
}

.date {
  font-size: 1.3em;
}

main {
  padding: 0 0.6em;
}

article {
  margin: 6em 0;
}

section, aside {
  margin-top: 64px;
  text-align: justify;
}

.note {
  font-size: 80%;
}

aside {
  margin-top: 6em;
  text-align: center;
}

aside h2 {
  margin-top: 48px;
}

.social {
  text-align: center;
}

.social {
  margin: 0 0 4em;
  padding: 0;
}

.social li {
  display: inline-block;
  margin: 0 0.3em;
  font-size: 2em;
}

.social a {
  color: white;
}

.social span {
  display: none;
}

footer {
  margin: 3em 0 1.6em;
  text-align: center;
}

footer .logo {
  max-width: 240px;
  width: 100%;
  height: auto;
}

.byline {
  font-size: 80%;
  text-align: center;
}

@media (min-width: 640px) {
  main {
    width: 42em;
    margin: 0 auto;
    padding: 0;
  }
}