style.css

* {
  zoom: 95%;
}

/* Galaxy Background */
.bg {
  background: url(https://i.ibb.co/87GbbFP/2799006.jpg) no-repeat;
  background-size: cover;
  height: 100%;
  width: 100%;
  position: fixed;
  top: 0;
  left: 0;
  z-index: -3;
}

.bg:before {
  content: "";
  width: 100%;
  height: 100%;
  background: #000;
  position: fixed;
  z-index: -1;
  top: 0;
  left: 0;
  opacity: 0.3;
}

@keyframes sf-fly-by-1 {
  from {
    transform: translateZ(-600px);
    opacity: 0.5;
  }

  to {
    transform: translateZ(0);
    opacity: 0.5;
  }
}

@keyframes sf-fly-by-2 {
  from {
    transform: translateZ(-1200px);
    opacity: 0.5;
  }

  to {
    transform: translateZ(-600px);
    opacity: 0.5;
  }
}

@keyframes sf-fly-by-3 {
  from {
    transform: translateZ(-1800px);
    opacity: 0.5;
  }

  to {
    transform: translateZ(-1200px);
    opacity: 0.5;
  }
}

.star-field {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  perspective: 600px;
  -webkit-perspective: 600px;
  z-index: -1;
}

.star-field .layer {
  box-shadow: -411px -476px #cccccc, 777px -407px #d4d4d4, -387px -477px #fcfcfc,
    -91px -235px #d4d4d4, 491px -460px #f7f7f7, 892px -128px #f7f7f7,
    758px -277px #ededed, 596px 378px #cccccc, 647px 423px whitesmoke,
    183px 389px #c7c7c7, 524px -237px #f0f0f0, 679px -535px #e3e3e3,
    158px 399px #ededed, 157px 249px #ededed, 81px -450px #ebebeb,
    719px -360px #c2c2c2, -499px 473px #e8e8e8, -158px -349px #d4d4d4,
    870px -134px #cfcfcf, 446px 404px #c2c2c2, 440px 490px #d4d4d4,
    414px 507px #e6e6e6, -12px 246px #fcfcfc, -384px 369px #e3e3e3,
    641px -413px #fcfcfc, 822px 516px #dbdbdb, 449px 132px #c2c2c2,
    727px 146px #f7f7f7, -315px -488px #e6e6e6, 952px -70px #e3e3e3,
    -869px -29px #dbdbdb, 502px 80px #dedede, 764px 342px #e0e0e0,
    -150px -380px #dbdbdb, 654px -426px #e3e3e3, -325px -263px #c2c2c2,
    755px -447px #c7c7c7, 729px -177px #c2c2c2, -682px -391px #e6e6e6,
    554px -176px #ededed, -85px -428px #d9d9d9, 714px 55px #e8e8e8,
    359px -285px #cfcfcf, -362px -508px #dedede, 468px -265px #fcfcfc,
    74px -500px #c7c7c7, -514px 383px #dbdbdb, 730px -92px #cfcfcf,
    -112px 287px #c9c9c9, -853px 79px #d6d6d6, 828px 475px #d6d6d6,
    -681px 13px #fafafa, -176px 209px #f0f0f0, 758px 457px #fafafa,
    -383px -454px #ededed, 813px 179px #d1d1d1, 608px 98px whitesmoke,
    -860px -65px #c4c4c4, -572px 272px #f7f7f7, 459px 533px #fcfcfc,
    624px -481px #e6e6e6, 790px 477px #dedede, 731px -403px #ededed,
    70px -534px #cccccc, -23px 510px #cfcfcf, -652px -237px whitesmoke,
    -690px 367px #d1d1d1, 810px 536px #d1d1d1, 774px 293px #c9c9c9,
    -362px 97px #c2c2c2, 563px 47px #dedede, 313px 475px #e0e0e0,
    839px -491px #e3e3e3, -217px 377px #d4d4d4, -581px 239px #c2c2c2,
    -857px 72px #cccccc, -23px 340px #dedede, -837px 246px white,
    170px -502px #cfcfcf, 822px -443px #e0e0e0, 795px 497px #e0e0e0,
    -814px -337px #cfcfcf, 206px -339px #f2f2f2, -779px 108px #e6e6e6,
    808px 2px #d4d4d4, 665px 41px #d4d4d4, -564px 64px #cccccc,
    -380px 74px #cfcfcf, -369px -60px #f7f7f7, 47px -495px #e3e3e3,
    -383px 368px #f7f7f7, 419px 288px #d1d1d1, -598px -50px #c2c2c2,
    -833px 187px #c4c4c4, 378px 325px whitesmoke, -703px 375px #d6d6d6,
    392px 520px #d9d9d9, -492px -60px #c4c4c4, 759px 288px #ebebeb,
    98px -412px #c4c4c4, -911px -277px #c9c9c9;
  transform-style: preserve-3d;
  position: absolute;
  top: 50%;
  left: 50%;
  height: 4px;
  width: 4px;
  border-radius: 2px;
}

.star-field .layer:nth-child(1) {
  animation: sf-fly-by-1 5s linear infinite;
}

.star-field .layer:nth-child(2) {
  animation: sf-fly-by-2 5s linear infinite;
}

.star-field .layer:nth-child(3) {
  animation: sf-fly-by-3 5s linear infinite;
}

:root {
  --sun-color: linear-gradient(135deg, #fff57b, #fa8607);
  --mercure-color: linear-gradient(135deg, #cecfd1, #60686b);
  --venus-color: linear-gradient(135deg, #ffa973, #a8683f);
  --terre-color: linear-gradient(135deg, #0059ff, lightgreen);
  --mars-color: linear-gradient(135deg, #e95020, #ff7a44);
  --jupiter-color: linear-gradient(135deg, #9f4523, #f7ad6f);
  --saturne-color: linear-gradient(135deg, #fff4c4, #f7be6d);
  --uranus-color: linear-gradient(135deg, #3dc5e3, #8ce7f5);
  --neptune-color: linear-gradient(135deg, #458ff2, #003184);
  --pluton-color: linear-gradient(135deg, #2a2e47, #9996ab);
  --star-color: linear-gradient(135deg, #ffffff, #858585);
  --planet-box-shadow: 0 0 50px 5px #ffffff;
}

/* Fin Galaxy Background */
.sun {
  width: 150px;
  height: 150px;
  background: var(--sun-color);
  box-shadow: 0 0 100px 20px #fa8607;
  border-radius: 50%;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.planet {
  border-radius: 50%;
  position: absolute;
  top: 50%;
  left: 50%;
  transform-origin: center;
}

/* Mercure */
.mercure {
  width: 15px;
  height: 15px;
  background: var(--mercure-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitmercure 7s linear infinite;
}

@keyframes orbitmercure {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-100px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-100px);
  }
}

/* Fin Mercure */

/* Venus */
.venus {
  width: 20px;
  height: 20px;
  background: var(--venus-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitvenus 8.5s linear infinite;
}

@keyframes orbitvenus {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-155px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-155px);
  }
}

/* Fin Venus */

/* Terre */
.terre {
  width: 25px;
  height: 25px;
  background: var(--terre-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitterre 12s linear infinite;
}

@keyframes orbitterre {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-210px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-210px);
  }
}

/* Fin Terre */

/* Mars */
.mars {
  width: 17px;
  height: 17px;
  background: var(--mars-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitmars 14s linear infinite;
}

@keyframes orbitmars {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-265px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-265px);
  }
}

/* Fin Mars */

/* Star Mars 1 */
.starmars1 {
  width: 4px;
  height: 4px;
  background: var(--star-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitstarmars1 2s linear infinite;
}

@keyframes orbitstarmars1 {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-25px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-25px);
  }
}

/* Fin Star Mars 1 */

/* Star Mars 2 */
.starmars2 {
  width: 4px;
  height: 4px;
  background: var(--star-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitstarmars2 2.5s linear infinite;
}

@keyframes orbitstarmars2 {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-35px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-35px);
  }
}

/* Fin Star Mars 2 */

/* Jupiter */
.jupiter {
  width: 55px;
  height: 55px;
  background: var(--jupiter-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitjupiter 18s linear infinite;
}

@keyframes orbitjupiter {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-320px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-320px);
  }
}

/* Fin Jupiter */

/* Saturne */
.saturne {
  width: 50px;
  height: 50px;
  background: var(--saturne-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitsaturne 22s linear infinite;
}

@keyframes orbitsaturne {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-375px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-375px);
  }
}

/* Fin Saturne */

/* Star Saturne */
.starsaturne {
  width: 10px;
  height: 10px;
  background: var(--star-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitstarsaturne 3s linear infinite;
}

@keyframes orbitstarsaturne {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-45px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-45px);
  }
}

/* Fin Star */

/* Uranus */
.uranus {
  width: 35px;
  height: 35px;
  background: var(--uranus-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbituranus 29s linear infinite;
}

@keyframes orbituranus {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-430px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-430px);
  }
}

/* Fin Uranus */

/* Neptune */
.neptune {
  width: 30px;
  height: 30px;
  background: var(--neptune-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitneptune 15.5s linear infinite;
}

@keyframes orbitneptune {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-485px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-485px);
  }
}

/* Fin Neptune */

/* Pluton */
.pluton {
  width: 35px;
  height: 35px;
  background: var(--pluton-color);
  box-shadow: var(--planet-box-shadow);
  animation: orbitpluton 19s linear infinite;
}

@keyframes orbitpluton {
  0% {
    transform: translate(-50%, -50%) rotate(0deg) translateY(-520px);
  }

  100% {
    transform: translate(-50%, -50%) rotate(1turn) translateY(-520px);
  }
}
/* Fin Pluton */