bpmn-js/example/app.css

* {
  box-sizing: border-box;
}

body, html {
  font-family: 'Open Sans', sans-serif;

  font-size: 12px;

  height: 100%;
  padding: 0;
  margin: 0;
}

a:link {
  text-decoration: none;
}

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

.content .intro {
  text-align: center;
  display: table;

  font-size: 16px;
  color: #111;
}

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

.content .canvas, 
.content.with-diagram .intro {
  display: none;
}

.content.with-diagram .canvas {
  display: block;
}

.buttons {
  position: fixed;
  bottom: 20px;
  left: 20px;
}

.logo {
  width: 80px;
  height: 80px;
  
  position: fixed;
  bottom: 20px;
  right: 20px;

  opacity: 0.8;
  
  background: no-repeat url('bpmn-io-icon.png');
}