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

body {
  font-family: sans-serif;
  max-width: 720px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
  background: #fafaf8;
  color: #2a2a2a;
  line-height: 1.7;
  font-size: 17px;
}

h1 {
  font-size: 1.6rem;
  margin-bottom: 0.25rem;
  font-weight: 700;
  color: #1a1a1a;
  border-bottom: 2px solid #1a1a1a;
  padding-bottom: 0.5rem;
}

h2 {
  font-size: 1.25rem;
  margin-top: 2rem;
  margin-bottom: 0.5rem;
  font-weight: 700;
  color: #1a1a1a;
}

h3 {
  font-size: 1.05rem;
  margin-top: 1.5rem;
  margin-bottom: 0.4rem;
  font-weight: 600;
}

p {
  margin-bottom: 1rem;
}

em {
  font-style: italic;
  color: #555;
}

strong {
  font-weight: 700;
}

a {
  color: #3a5a8c;
  text-decoration: none;
  border-bottom: 1px solid #3a5a8c;
}

a:hover {
  color: #1a3a5c;
  border-bottom-color: #1a3a5c;
}

hr {
  border: none;
  border-top: 1px solid #d0d0d0;
  margin: 2rem 0;
}

ul, ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.4rem;
}

blockquote {
  border-left: 3px solid #888;
  padding-left: 1rem;
  margin: 1rem 0;
  color: #555;
  font-style: italic;
}

nav {
  background: #f0f0ec;
  padding: 0.75rem 1rem;
  margin-bottom: 2rem;
  border-radius: 4px;
  font-size: 0.9rem;
  display:flex;
  
}

nav a {
  margin-right: 1.25rem;
  border-bottom: none;
}

nav a:hover {
  border-bottom: 1px solid #1a3a5c;
}

nav a.current {
  font-weight: 700;
  color: #1a1a1a;
}

.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
}