* {
  box-sizing: border-box;
}

body {
  font-family: Arial, Helvetica, sans-serif;
  background-color: #ccc;
  margin: 0;
}

/* Header */
header {
  background-color: #2c5f2d;
  padding: 10px 20px;
  text-align: center;
  font-size: 28px;
  color: white;
}

/* Two-column layout: sticky nav + article */
nav {
  position: sticky;
  top: 10px;
  float: left;
  width: 20%;
  background: #ccc;
  padding: 20px;
  font-size: 17px;
  border-right: 1px solid #bbb;
}

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

nav a {
  display: block;
  text-decoration: none;
  color: #333;
  padding: 7px 10px;
  border-radius: 4px;
}

nav a:hover {
  background-color: #b8d8b8;
  color: #000;
}

nav ul ul {
  padding-left: 15px;
  font-size: 0.93em;
}

nav ul ul a {
  color: #555;
}

article {
  float: left;
  padding: 20px 30px;
  width: 80%;
  background-color: #f1f1f1;
}

section::after {
  content: "";
  display: table;
  clear: both;
}

/* Footer */
footer {
  background-color: #2c5f2d;
  padding: 10px;
  text-align: center;
  color: white;
}

footer a {
  color: #b8d8b8;
}

/* Tables */
table {
  border-collapse: collapse;
  margin-top: 10px;
  margin-bottom: 10px;
  font-family: monospace;
  font-size: 0.92em;
}

th, td {
  border: 1px solid #bbb;
  padding: 5px 10px;
  text-align: right;
}

th {
  background-color: #d4e8d4;
  text-align: center;
}

td:first-child {
  text-align: left;
}

/* Code blocks */
pre {
  background-color: #e8f5e9;
  border-left: 4px solid #4caf50;
  padding: 10px 14px;
  overflow-x: auto;
  font-size: 0.9em;
  border-radius: 3px;
}

code {
  background-color: #e8f5e9;
  padding: 1px 5px;
  border-radius: 3px;
  font-size: 0.93em;
}

pre code {
  background: none;
  padding: 0;
}

/* Info boxes */
.info-box {
  background-color: #e8f5e9;
  border: 1px solid #4caf50;
  border-radius: 4px;
  padding: 12px 16px;
  margin: 14px 0;
}

.info-box strong {
  color: #2c5f2d;
}

/* Responsive */
@media (max-width: 650px) {
  nav, article {
    width: 100%;
    float: none;
  }
  nav {
    position: static;
  }
}