css
/* Stylesheet for Time-Traveler's Guide */

/* Color scheme inspired by the vibrant hues of neon lights in a retro-futuristic time-travel hub */
body {
  background-color: #000;
  color: #0ff;
  margin: 0;
  padding: 0;
}

h1, h2, h3, p, a {
  color: #fff;
}

h1 {
  font-size: 36px;
  font-weight: bold;
  text-shadow: 0 0 5px #666;
  border-bottom: 4px solid #666;
}

h2 {
  font-size: 24px;
  font-weight: bold;
  text-shadow: 0 0 5px #666;
  border-bottom: 4px solid #666;
}

h3 {
  font-size: 18px;
  font-weight: bold;
  text-shadow: 0 0 5px #666;
  border-bottom: 4px solid #666;
}

p {
  margin-bottom: 20px;
  padding-bottom: 20px;
}

a {
  text-decoration: none;
  color: #f00;
  border-bottom: 4px solid #666;
}

a:hover {
  text-decoration: none;
  color: #0f0;
  border-bottom: 2px solid #666;
}

/* Hyperlinks for subpages */
a.subpage {
  text-decoration: none;
  color: #f00;
  background-color: #f00;
  border-bottom: 4px solid #666;
}

a.subpage:hover {
  text-decoration: none;
  color: #0f0;
  background-color: #0f0;
  border-bottom: 2px solid #666;
}

/* Hyperlinks for subpages with specific styles */
a.subpage.style1 {
  text-decoration: none;
  color: #ff0;
  background-color: #ff0;
  border-bottom: 4px solid #666;
  font-weight: bold;
}

a.subpage.style1:hover {
  text-decoration: none;
  color: #0f0;
  background-color: #0f0;
  border-bottom: 2px solid #666;
  font-weight: bold;
}

/* Hyperlinks for subpages with specific styles 2 */
a.subpage.style2 {
  text-decoration: none;
  color: #0f0;
  background-color: #0f0;
  border-bottom: 4px solid #666;
  font-style: italic;
}

a.subpage.style2:hover {
  text-decoration: none;
  color: #f00;
  background-color: #f00;
  border-bottom: 2px solid #666;
  font-style: italic;
}