* {
  box-sizing: border-box; }

body, html {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 12px;
  height: 100%;
  padding: 0;
  margin: 0; }

a:link {
  text-decoration: none; }

.content,
.content > div {
  width: 100%;
  height: 100%;
  position: relative; }

.content > .message {
  text-align: center;
  display: table;
  font-size: 16px;
  color: #111; }

.content > .message .note {
  vertical-align: middle;
  text-align: center;
  display: table-cell; }

.content .error .details {
  max-width: 500px;
  font-size: 12px;
  margin: 20px auto;
  text-align: left; }

.content .error pre {
  border: solid 1px #CCC;
  background: #EEE;
  padding: 10px; }

.content:not(.with-error) .error,
.content.with-error .intro,
.content.with-diagram .intro {
  display: none; }

.content .canvas,
.content.with-error .canvas {
  visibility: hidden; }

.content.with-diagram .canvas {
  visibility: visible; }

.buttons {
  position: fixed;
  bottom: 20px;
  left: 20px;
  padding: 0;
  margin: 0;
  list-style: none; }

.buttons > li {
  display: inline-block;
  margin-right: 10px; }

.buttons > li > a {
  background: #DDD;
  border: solid 1px #666;
  display: inline-block;
  padding: 5px; }

.buttons a {
  opacity: 0.3; }

.buttons a.active {
  opacity: 1.0; }