
.wrapper {
  display: flex;
}
.doc__nav {
  width: 240px;
  background-color: #f9f9f9;
  padding: 2em 1.5em;
  height: 100vh;
  box-shadow: 2px 0 5px rgba(0, 0, 0, 0.05);
  position: sticky;
  top: 0;
}
.doc__nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.doc__nav h1 {
  font-size: 1.3em;
  color: #333;
  margin-bottom: 1em;
}
.doc__nav li {
  margin: 0.5em 0;
}
.doc__nav a {
  color: #0077cc;
  font-size: 1em;
  display: block;
}
.doc__content {
  padding: 2em 3em;
  max-width: 960px;
  flex: 1;
}
.section__title {
  font-size: 1.6em;
  margin-top: 1.2em;
  border-bottom: 1px solid #e0e0e0;
  padding-bottom: 0.3em;
  margin-bottom: 1em;
}
footer.footer {
  text-align: center;
  padding: 2em;
  font-size: 0.9em;
  color: #aaa;
}

.doc__nav li {
  list-style-type: none;
  margin: 0.5em 0;
}
.doc__nav li::marker {
  display: none;
}
