/* common.css - 共通スタイル */
body {
  font-family: "Helvetica Neue", sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #fff;
  margin: 0;
  padding: 0;
}

a {
  color: #007acc;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* レイアウト */
header, main, footer {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem;
}


@media screen and (max-width: 768px) {
  nav ul {
    flex-direction: column;
  }

  .menu-toggle {
    display: block;
  }

  .main-nav {
    display: none;
  }

  .main-nav.open {
    display: block;
  }
}