html, body {
  height: 100%;
}

body {
  margin: 0;
  padding: 24px;
  font-family: Arial, sans-serif;
  background: #111;
  color: white;
}

.page {
  min-height: calc(100vh - 48px);
  display: flex;
  flex-direction: column;
}

.wrap {
  max-width: 700px;
  width: 100%;
  margin: 0 auto;
  flex: 1;
}

h1 {
  text-align: center;
  margin-bottom: 24px;
  font-weight: 600;
}

#first {
  margin-top: 50px;
}

.book-link {
  display: block;
  background: #1d1d1d;
  color: white;
  text-decoration: none;
  padding: 16px 18px;
  margin-bottom: 12px;
  border-radius: 12px;
  border: 1px solid #333;
  text-align: center;
  font-weight: 600;
}

.book-link:hover {
  background: #00CC00;
  color: black;
}

.book-link:active {
  background: #009900;
  color: black;
}

footer {
  margin-top: 24px;
}

.footertext {
  display: block;
  text-align: center;
}