body {
  color: #333;
  background-color: #f8f9fa;
  padding: 20px;
  margin: 0;
  font-family: "Helvetica Neue", sans-serif;
  line-height: 1.3;
  font-size: 17px; }
  body * {
    font-size: 17px; }

a {
  color: #068cdf; }
  a:visited {
    color: #333; }
  a:hover {
    color: #056dad; }

h1, h1 a {
  margin-top: 0;
  font-size: 34px; }

h1 {
  margin-bottom: 10px; }

h2 {
  margin-bottom: 15px;
  font-size: 23.8px; }

pre {
  font-family: "courier new", monospace;
  background-color: #555;
  color: #eee;
  padding: 5px;
  overflow: auto; }

div.board {
  float: left;
  max-width: 450px;
  max-height: 430px;
  width: calc(100vw - 40px);
  height: calc(95vw - 40px);
  margin-right: 20px;
  margin-bottom: 20px; }

.clearfix::after {
  content: "";
  clear: both;
  display: table; }