body {
  background-color: #121a2d;
  min-height: 100vh;
}

.mdl-tabs.is-upgraded .mdl-tabs__tab.is-active::after {
  background: #dc700e !important;
}

.main-content > h1 {
  color: white;
  text-align: center;
  padding-top: 15%;
  padding-bottom: 5%;
  font-family: 'Anton', sans-serif;
  text-transform: uppercase;
  font-size: 5rem;
  letter-spacing: 0.2rem;
  text-shadow: 5px 5px 0px hsl(0, 0%, 13%);
}

.main-content > p {
  font-family: 'Roboto', sans-serif;
  font-weight: 300;
  color: white;
  font-size: 1.4rem;
  line-height: 2.3rem;
}

@media screen and (max-width: 40em) {
  .main-content > h1 {
    font-size: 3rem;
  }
  .main-content > p {
    font-size: 1.3rem;
    line-height: 1.7rem;
  }
  @media screen and (max-width: 30em) {
    .tab-docs:before {
      content: 'Docs ';
    }
  }
}

.main-content-text {
  max-width: 40em;
  padding: 10px;
  background-color: rgba(33, 33, 33, 0.9);
  border: 5px solid rgba(33, 33, 33, 0.95);
  border-radius: 0px;
}

.mdl-tabs__tab-bar {
  font-family: 'Roboto', sans-serif;
  font-size: 1.5rem;
  border-bottom: none;
  letter-spacing: 0.1rem;
}

.mdl-tabs__tab {
  font-weight: 400;
  color: white;
  width: 33.3%;
  padding: 0px;
  transition: all 0.5s ease;
}

.mdl-tabs__tab.is-active {
  font-weight: 700;
  color: white !important;
  text-transform: uppercase;
}

.mdl-mini-footer {
  padding-top: 0px;
  padding-bottom: 0px;
  background-color: rgba(33, 33, 33, 0.9);
  border: 5px solid rgba(33, 33, 33, 0.95);
  border-radius: 0px;
  border-bottom-width: 0px;
}

/* Zelle zentrieren (https://stackoverflow.com/q/31463632) */
.center-items {
  justify-content: center;
}

.mdl-layout-title {
  color: rgb(0, 0, 0, 0.87)
}

.header-container {
  top: 0px;
  left: 0px;
  width: 100%;
}

.play-button {
  width: 150px;
  margin-left: calc(50% - 75px);
}

.header-image {
  position: fixed;
  width: 100%;
  height: 100vh;
  background-image: url('background.gif');
  background-size: cover;
  background-position: bottom;
  z-index: -10;
  /* https://stackoverflow.com/questions/14068103/disable-antialising-when-scaling-images */
  image-rendering: -moz-crisp-edges;
  image-rendering: -moz-crisp-edges;
  image-rendering: -o-crisp-edges;
  image-rendering: -webkit-optimize-contrast;
  -ms-interpolation-mode: nearest-neighbor;
  transition: all ease 1s;
}

.header-image-overlay {
  background-image: url('overlay.png');
  z-index: -9;
}

.header-title {
  position: absolute;
  width: 100%;
  padding-top: 20%;
  z-index: 3;
}

.header-title > h1 {
  text-align: center;
  font-weight: 700;
  font-size: 8em;
  color: white;
}

.header-title > p {
  text-align: center;
  color: white;
}

.footer-box {
  margin-top: 50px;
  margin-bottom: -10px;
  vertical-align: bottom;
}

.material-icons.md-18 { font-size: 18px; }
.material-icons.md-24 { font-size: 24px; }
.material-icons.md-36 { font-size: 36px; }
.material-icons.md-48 { font-size: 48px; }