/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-size: 14px;
  line-height: 1.5;
  color: #2e3440;
  background-color: #eceff4;
  display: flex;
  min-height: 100vh;
}

/* Sidebar Navigation */
#sidebar {
  width: 260px;
  background-color: #d8dee9;
  border-right: 2px solid #4c566a;
  padding: 30px 20px;
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  overflow-y: auto;
}

.nav-header {
  margin-bottom: 20px;
  padding-bottom: 15px;
  border-bottom: 1px solid #4c566a;
}

.nav-header h2 {
  font-size: 18px;
  font-weight: bold;
  color: #2e3440;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

#sidebar ul {
  list-style: none;
}

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

#sidebar a {
  color: #4c566a;
  text-decoration: none;
  font-size: 13px;
  display: block;
  padding: 6px 10px;
  border-left: 2px solid transparent;
  transition: all 0.2s ease;
}

#sidebar a:hover {
  color: #2e3440;
  border-left-color: #2e3440;
  background-color: #eceff4;
}

/* Main Content Area */
main {
  margin-left: 260px;
  flex: 1;
  padding: 40px 60px;
  max-width: 1000px;
}

article {
  background-color: #ffffff;
  border: 2px solid #4c566a;
  padding: 40px;
}

/* Typography */
h1 {
  font-size: 26px;
  font-weight: bold;
  color: #2e3440;
  margin-bottom: 30px;
  line-height: 1.3;
}

h2 {
  font-size: 20px;
  font-weight: bold;
  color: #2e3440;
  margin-top: 35px;
  margin-bottom: 15px;
  padding-bottom: 8px;
  border-bottom: 1px solid #d8dee9;
}

h3 {
  font-size: 16px;
  font-weight: bold;
  color: #4c566a;
  margin-top: 25px;
  margin-bottom: 12px;
}

p {
  margin-bottom: 15px;
  color: #2e3440;
}

/* Intro Section */
.intro {
  padding: 20px;
  background-color: #eceff4;
  border: 1px solid #4c566a;
  margin-bottom: 30px;
}

.intro p {
  margin-bottom: 0;
  font-size: 15px;
  line-height: 1.6;
}

/* Sections */
section {
  margin-bottom: 25px;
}

section:last-of-type {
  margin-bottom: 0;
}

/* Links */
a {
  color: #4c566a;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

a:hover {
  color: #2e3440;
  text-decoration-thickness: 2px;
}

/* Code Elements */
code {
  font-family: 'Courier New', Courier, monospace;
  font-size: 13px;
  background-color: #d8dee9;
  padding: 2px 6px;
  border: 1px solid #4c566a;
  border-radius: 0;
}

pre {
  background-color: #2e3440;
  color: #eceff4;
  padding: 15px;
  border: 2px solid #4c566a;
  overflow-x: auto;
  margin: 15px 0;
}

pre code {
  background-color: transparent;
  border: none;
  padding: 0;
  color: #eceff4;
  font-size: 12px;
}

/* Resources Section Styling */
#resources {
  padding: 20px;
  border: 2px solid #4c566a;
  background-color: #d8dee9;
  margin-top: 40px;
}

#resources h2 {
  margin-top: 0;
  border-bottom-color: #4c566a;
}

/* Responsive Design */
@media (max-width: 968px) {
  #sidebar {
    width: 220px;
  }

  main {
    margin-left: 220px;
    padding: 30px 40px;
  }

  article {
    padding: 30px;
  }
}

@media (max-width: 768px) {
  body {
    flex-direction: column;
  }

  #sidebar {
    position: static;
    width: 100%;
    height: auto;
    border-right: none;
    border-bottom: 2px solid #4c566a;
    padding: 20px;
  }

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

  article {
    padding: 20px;
    border-width: 1px;
  }

  h1 {
    font-size: 22px;
  }

  h2 {
    font-size: 18px;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 13px;
  }

  main {
    padding: 15px;
  }

  article {
    padding: 15px;
  }

  h1 {
    font-size: 20px;
    margin-bottom: 20px;
  }

  h2 {
    font-size: 16px;
    margin-top: 25px;
  }

  #sidebar a {
    font-size: 12px;
  }
}