html {
  box-sizing: border-box;
  font-size: 62.5%;
}
html *,
html *:before,
html *:after {
  box-sizing: inherit;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  background-color: #251C2D;
}

.system {
  position: relative;
  width: 100%;
  max-width: 700px;
  padding-top: 100%;
}
@media (min-width: 700px) {
  .system {
    padding-top: 700px;
  }
}
.system__sun {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}
.system__orbit {
  position: absolute;
  top: 50%;
  left: 50%;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 100%;
  transform: translate(-50%, -50%);
  animation: spin infinite linear both;
}
.system__orbit:nth-child(1) {
  width: calc(10%);
  height: calc(10%);
}
.system__orbit:nth-child(2) {
  width: calc(20%);
  height: calc(20%);
}
.system__orbit:nth-child(3) {
  width: calc(30%);
  height: calc(30%);
}
.system__orbit:nth-child(4) {
  width: calc(40%);
  height: calc(40%);
}
.system__orbit:nth-child(5) {
  width: calc(50%);
  height: calc(50%);
}
.system__orbit:nth-child(6) {
  width: calc(60%);
  height: calc(60%);
}
.system__orbit:nth-child(7) {
  width: calc(70%);
  height: calc(70%);
}
.system__orbit:nth-child(8) {
  width: calc(80%);
  height: calc(80%);
}
.system__orbit:nth-child(9) {
  width: calc(90%);
  height: calc(90%);
}
.system__orbit:nth-child(10) {
  width: calc(100%);
  height: calc(100%);
}
.system__orbit--sun {
  border: none;
}
.system__orbit--mercury {
  animation-duration: 1s;
}
.system__orbit--venus {
  animation-duration: 2.6s;
}
.system__orbit--earth {
  animation-duration: 4.1s;
}
.system__orbit--mars {
  animation-duration: 7.8s;
}
.system__orbit--jupiter {
  animation-duration: 49.8s;
}
.system__orbit--saturn {
  animation-duration: 120.3s;
}
.system__orbit--uranus {
  animation-duration: 348.4s;
}
.system__orbit--neptune {
  animation-duration: 684.4s;
}
.system__orbit--pluto {
  animation-duration: 1028.6s;
}
.system__planet {
  position: absolute;
  top: 50%;
  left: -12px;
  width: 25px;
  height: 25px;
  border-radius: 100%;
  transform: translateY(-50%);
}
.system__icon {
  width: 100%;
  height: 100%;
}

@keyframes spin {
  from {
    transform: translate(-50%, -50%);
  }
  to {
    transform: translate(-50%, -50%) rotate(360deg);
  }
}