.background {
  position: fixed;
  overflow: hidden;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  background: radial-gradient(circle at 50% 50%, #3f575f 0%, #1b9e88 70%, #ff8080 100%);
  display: flex;
  flex-grow: 1;
  z-index: -1;
  opacity: 0.5;
  animation: gradientAnimation 10s ease infinite;
}

@keyframes gradientAnimation {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}