@media (min-width: 1200px) {
  #navbar {
    position: fixed;
    width: 300px;
    top: 0;
    left: 0;
    height: 100%;
    border-right: 2px solid gray;
  }

  .nav-link {
    padding: 10px 15px;
    border-top: 2px solid gray;
    display: block;
  }

  nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
  }

  #main-doc {
    position: absolute;
    left: 310px;
  }
}

body {
  font-family: sans-serif;
  color: rgb(45, 45, 45);
  font-size: 15px;
  line-height: 1.5;
}

header {
  font-size: 2em;
  color: black;
  padding: 0 15px;
  margin: 10px 0;
}

.nav-link {
  font-size: 1.2em;
  color: rgb(45, 45, 45);
  text-decoration: none;
}

p {
  padding: 0 25px;
}

code {
  display: block;
  background-color: rgb(237, 237, 237);
  margin: 20px 35px;
  padding: 15px;
}