html, body {
  height: 100%;
  overflow-x: hidden;
  margin: 0;
}

nav {
  position: fixed;
  width: 150px;
  height: 100%;
  left: 0;
  top: 0;
  background: #ddffff;
}
nav a {
  display: block;
  margin: 10px;
}

.container {
  position: fixed;
  width: calc(100% - 150px);
  height: 100%;
  left: 150px;
  top: 0;
  padding: 10px;
  overflow-y: scroll;
}

img {
  max-width: 100%;
}

@media screen and (max-width: 621px) {
  nav {
    width: 100%;
    height: 50px;
    left: 0;
    top: 0;
  }
  nav a {
    display: inline;
  }
  .container {
    width: 100%;
    height: calc(100% - 50px);
    left: 0;
    top: 50px;
  }
}
footer {
  border-radius: 10px;
  padding: 10px;
  margin: 10px 0;
  background: #ddd;
}

blockquote {
  display: block;
  background: #ddd;
  padding: 0 10px;
  margin: 10px;
  border-radius: 10px;
  white-space: pre-wrap;
}
blockquote p {
  margin: 0;
}

code {
  display: block;
  background: #ddd;
  padding: 10px;
  border-radius: 10px;
  white-space: pre-wrap;
}