css
body {
  background: #f2f2f2;
  color: #333;
  font-family: 'Open Sans', sans-serif;
  font-size: 18px;
  line-height: 1.2;
  margin: 0;
  padding: 0;
  border: 2px solid black;
}

a {
  text-decoration: none;
  color: #00f;
  font-weight: bold;
  text-align: center;
  border: 2px solid black;
  background: #333;
  padding: 4px 8px;
  text-decoration: none;
  display: inline-block;
  border-radius: 4px;
  transition: background 0.2s ease-in-out;
}

a:hover {
  background: #000;
  color: #fff;
  cursor: pointer;
}

h1 {
  font-weight: bold;
  font-size: 36px;
  line-height: 1.2;
  margin-bottom: 0;
  text-shadow: 0 0 0 #000;
  border-bottom: 2px solid #666;
  padding-bottom: 4px;
  border-top: 2px solid black;
  background: #f2f2f2;
}

h2 {
  font-weight: bold;
  font-size: 28px;
  line-height: 1.2;
  margin-bottom: 0;
  text-shadow: 0 0 0 #000;
  border-bottom: 2px solid #666;
  padding-bottom: 4px;
  border-top: 2px solid black;
  background: #f2f2f2;
}

h3 {
  font-weight: bold;
  font-size: 24px;
  line-height: 1.2;
  margin-bottom: 0;
  text-shadow: 0 0 0 #000;
  border-bottom: 2px solid #666;
  padding-bottom: 4px;
  border-top: 2px solid black;
  background: #f2f2f2;
}

h4 {
  font-weight: bold;
  font-size: 20px;
  line-height: 1.2;
  margin-bottom: 0;
  text-shadow: 0 0 0 #000;
  border-bottom: 2px solid #666;
  padding-bottom: 4px;
  border-top: 2px solid black;
  background: #f2f2f2;
}

p {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 16px;
  line-height: 1.2;
  text-shadow: 0 0 0 #000;
  background: #f2f2f2;
}

img {
  display: block;
  margin: 0 auto;
  padding: 0;
  border: 0;
  border-radius: 0 0 4px 4px;
  box-shadow: 0 2px 4px #000;
  transition: box-shadow 0.2s ease-in-out;
}

img:hover {
  box-shadow: 0 4px 8px #000;
  transition: box-shadow 0.2s ease-in-out;
}

code {
  font-family: 'Consolas', 'Menlo', 'monospace';
  font-size: 14px;
  line-height: 1.2;
  background: #333;
  border: 1px solid #666;
  padding: 2px 4px;
  border-radius: 2px;
  white-space: pre;
  color: #fff;
  text-shadow: 0 0 0 #000;
}

code::before {
  content: ' ';
  display: inline-block;
  width: 2px;
  height: 16px;
  border-top: 2px solid #000;
  margin-right: 6px;
  font-size: 14px;
  line-height: 1.2;
  vertical-align: middle;
  text-align: left;
  background: #333;
  border: 1px solid #666;
  border-radius: 2px;
  color: #fff;
  text-shadow: 0 0 0 #000;
}

code::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 16px;
  border-top: 2px solid #000;
  margin-left: 6px;
  font-size: 14px;
  line-height: 1.2;
  vertical-align: middle;
  text-align: right;
  background: #333;
  border: 1px solid #666;
  border-radius: 2px;
  color: #fff;
  text-shadow: 0 0 0 #000;
}

pre {
  font-family: 'Consolas', 'Menlo', 'monospace';
  font-size: 14px;
  line-height: 1.2;
  background: #333;
  border: 1px solid #666;
  padding: 4px 8px;
  border-radius: 4px;
  white-space: pre;
  color: #fff;
  text-shadow: 0 0 0 #000;
  overflow: auto;
  margin: 0;
  padding: 0;
  border: 1px solid black;
}

pre::before {
  content: ' ';
  display: inline-block;
  width: 2px;
  height: 16px;
  border-top: 2px solid #000;
  margin-right: 6px;
  font-size: 14px;
  line-height: 1.2;
  vertical-align: middle;
  text-align: left;
  background: #333;
  border: 1px solid #666;
  border-radius: 2px;
  color: #fff;
  text-shadow: 0 0 0 #000;
}

pre::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 16px;
  border-top: 2px solid #000;
  margin-left: 6px;
  font-size: 14px;
  line-height: 1.2;
  vertical-align: middle;
  text-align: right;
  background: #333;
  border: 1px solid #666;
  border-radius: 2px;
  color: #fff;
  text-shadow: 0 0 0 #000;
}