*, *::before, *::after { box-sizing: border-box; }

body {
  font-family: sans-serif;
  max-width: 740px;
  margin: 60px auto;
  padding: 0 20px;
  color: #222;
  line-height: 1.6;
}

a { color: #1a0dab; }

h1 { margin-bottom: 4px; }

.back { margin-top: 40px; }