body {
  width: 1000px;
  margin: 0 auto;
  min-height: 100vh;

}
header {
  height: 1000px;
  font-size: clamp(4px, 2vw, 20px);
}



/* パステル青緑 (56,146,136) */
h1 {
  width: 1000px;
  background-color: rgb(56,146,136);

}
nav ul {
  list-style: none;
}

#footer {
  width: 1000px;
  font-size: 12px;
  color: #aaa;
  padding: 15px 0 0 15px;
  border-top: 3px double #ccc;
  box-sizing: border-box;
}