.browser-mockup {
  border-top: 2em solid rgba(240, 240, 240, 0.7);
  box-shadow: 0 0.1em 1em 0 rgba(0, 0, 0, 0.4);
  position: relative;
  border-radius: 3px 3px 0 0;
  padding: 15px;
  background-color: DarkSlateGray;
}

.browser-mockup:before {
  display: block;
  position: absolute;
  content: '';
  top: -1.25em;
  left: 1em;
  width: 0.5em;
  height: 0.5em;
  border-radius: 50%;
  background-color: #f44;
  box-shadow: 0 0 0 2px #f44, 1.5em 0 0 2px #9b3, 3em 0 0 2px #fb5;
}

.browser-mockup.with-tab:after {
  display: block;
  position: absolute;
  content: '';
  top: -2em;
  left: 5.5em;
  width: 20%;
  height: 0em;
  border-bottom: 2em solid white;
  border-left: 0.8em solid transparent;
  border-right: 0.8em solid transparent;
}

.browser-mockup.with-url:after {
  display: block;
  position: absolute;
  content: '';
  top: -1.6em;
  left: 5.5em;
  width: calc(100% - 6em);
  height: 1.2em;
  border-radius: 2px;
  background-color: white;
}

.browser-mockup > * {
  display: block;
}

/* Custom code for the demo */

.browser-mockup {
  margin: 2em;
  flex: 1;
}