* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  display: flex;
  background-color: #f4f6f8;
  color: #2c3e50;
  line-height: 1.6;
}

#navbar {
  width: 260px;
  min-height: 100vh;
  background-color: #1f2a40;
  color: white;
  padding: 20px;
  position: fixed;
  overflow-y: auto;
}

#navbar header {
  font-size: 1.5rem;
  margin-bottom: 20px;
  font-weight: bold;
  border-bottom: 1px solid #3c4b63;
  padding-bottom: 10px;
}

#navbar ul {
  list-style: none;
  margin-top: 10px;
}

#navbar li {
  margin-bottom: 12px;
}

#navbar a {
  color: #e0e0e0;
  text-decoration: none;
  transition: color 0.2s ease;
}

#navbar a:hover {
  color: #4fc3f7;
}


#main-doc {
  margin-left: 280px;
  padding: 40px 20px;
  max-width: 900px;
}

section {
  margin-bottom: 60px;
}

h2 {
  font-size: 1.8rem;
  color: #1f2a40;
  margin-bottom: 10px;
  border-left: 5px solid #4fc3f7;
  padding-left: 10px;
}

p {
  margin-bottom: 16px;
}

ul {
  padding-left: 20px;
  margin-bottom: 16px;
}

ul li {
  margin-bottom: 8px;
}


code {
  background-color: #e1ecf4;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: monospace;
}

@media screen and (max-width: 768px) {
  #navbar {
    position: static;
    width: 100%;
    height: auto;
    border-bottom: 1px solid #ccc;
  }

  #main-doc {
    margin-left: 0;
    padding: 20px;
  }
}