:root {
  font-size: 16px;
}

body {
  margin: 0;
  padding: 0;
}

main {
  display: grid;
  height: inherit;
  place-items: center;
}

h1,
h2,
h3,
h4,
h5,
h6,
p {
  font-family: sans-serif;
  color: #111;
}

h1 {
  font-size: 4.5rem;
}

p.subtitle {
  font-size: 2.5rem;
}

.text-center {
  text-align: center;
}

.backstretch {
  width: 100vw;
  height: 400px;
  background: #1e5799; /* Old browsers */
  background: -moz-radial-gradient(
    center,
    ellipse cover,
    #1e5799 0%,
    #7db9e8 100%
  ); /* FF3.6+ */
  background: -webkit-gradient(
    radial,
    center center,
    0px,
    center center,
    100%,
    color-stop(0%, #1e5799),
    color-stop(100%, #7db9e8)
  ); /* Chrome,Safari4+ */
  background: -webkit-radial-gradient(
    center,
    ellipse cover,
    #1e5799 0%,
    #7db9e8 100%
  ); /* Chrome10+,Safari5.1+ */
  background: -o-radial-gradient(
    center,
    ellipse cover,
    #1e5799 0%,
    #7db9e8 100%
  ); /* Opera 12+ */
  background: -ms-radial-gradient(
    center,
    ellipse cover,
    #1e5799 0%,
    #7db9e8 100%
  ); /* IE10+ */
  background: radial-gradient(
    ellipse at center,
    #1e5799 0%,
    #7db9e8 100%
  ); /* W3C */
  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#1e5799', endColorstr='#7db9e8',GradientType=1 ); /* IE6-9 fallback on horizontal gradient */
}

.backstretch.animated {
  -webkit-animation: filter-animation 8s infinite;
  animation: filter-animation 8s infinite;
  width: 100vw;
  height: 100vh;
}

@-webkit-keyframes filter-animation {
  0% {
    -webkit-filter: hue-rotate(0deg);
  }

  50% {
    -webkit-filter: hue-rotate(100deg);
  }

  100% {
    -webkit-filter: hue-rotate(0deg);
  }
}

@keyframes filter-animation {
  0% {
    filter: hue-rotate(0deg);
  }

  50% {
    filter: hue-rotate(100deg);
  }

  100% {
    filter: hue-rotate(0deg);
  }
}