@import url("https://fonts.googleapis.com/css?family=Ubuntu+Mono");
html,
body {
  background: #141E30;
  /* fallback for old browsers */
  /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to bottom, #243B55, #141E30);
  /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
  background: url(http://lars-rueggeberg/bg.JPG);
  background-size: cover;
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  box-sizing: border-box;
}

.window {
  display: block;
  overflow: auto;
  box-shadow: 0 0.8em 1.5em rgba(51, 51, 51, 0.6), 0 0.5em 2em rgba(51, 51, 51, 0.6);
  width: 600px;
  height: 400px;
  background: rgba(0, 0, 0, 0.75);
}
.window .bar {
  padding: .5em;
  flex: 0 0 auto;
  display: flex;
  background: linear-gradient(to bottom, #eaeaea, #d2d2d2);
  border-bottom: 1px solid #7d7d7d;
  color: #4c4c4c;
}
.window .bar .title {
  margin: 0;
  display: inline-block;
  flex: 1 1 auto;
  line-height: 1;
  font-family: 'Helvetica Neue', 'Helvetica', 'Lucida Grande', 'Lucida', 'Arial';
  text-align: center;
}
.window .bar .buttons {
  display: inline-block;
  flex: 0 0 auto;
}
.window .bar .buttons .button {
  margin: 0 .5em 0 0;
  height: 1em;
  width: 1em;
  display: inline-block;
  float: left;
  border-radius: 50%;
  box-shadow: inset 0 0 0.1em rgba(51, 51, 51, 0.4);
}
.window .bar .buttons .button:nth-child(1) {
  position: relative;
  background: #fe6058;
}
.window .bar .buttons .button:nth-child(1)::after {
  width: .35em;
  height: .35em;
  display: block;
  position: absolute;
  top: 50%;
  left: 50%;
  -webkit-transform: translate(-50%, -50%);
          transform: translate(-50%, -50%);
  border-radius: 50%;
  background: #4c0000;
  content: '';
}
.window .bar .buttons .button:nth-child(2) {
  background: #fdbd34;
}
.window .bar .buttons .button:nth-child(3) {
  background: #23c944;
}
.window .console {
  padding: 1em;
  box-sizing: border-box;
  color: #f9f9f9;
  font-size: 1.5em;
  font-family: 'Ubuntu Mono', monospace;
  line-height: 1;
}
.window .console .line {
  display: block;
}
.window .console .mandelbrot {
  white-space: pre;
  line-height: .5;
}