html {
  box-sizing: border-box;
}

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

body {
  background-color: #efefef;
}

#container {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.media * {
  width: 100%;
}

.media {
  margin: 20px;
}

.controls button {
  padding: 10px 30px;
}

.controls {
  margin: 10px 0;
  position: sticky;
  top: 0;
  width: 100%;
  background-color: #efefef;
  padding: 10px;
  z-index: 9999;
}

.position {
  margin-top: 10px;
}

.footer {
  margin-bottom: 40px;
}