效果地址：

HTML code：

CSS code：

html,body{
      　　margin: 0;　　padding: 0;}body{
          height: 100vh;    background-color: black;}.stars{
          position: relative;    width: 100%;    height: 100%;}.stars span{
          display: inline-block;    position: absolute;    width: 5px;    height: 5px;    background-color: white;    transform: rotate(45deg);    /* 使星星模糊一点 */    opacity: 0.2;    /* 动画名称 动画时间  速度  开始时间 次数 */    animation: blinking 1s linear var(--d) infinite;}/* blinking : 闪烁 */@keyframes blinking{
          0%,100%{      opacity: 0.2;    }    50%{      /* 星星大小放大 1.5倍 ，旋转45度成菱形 */      transform: scale(1.5) rotate(45deg);      opacity: 1;    }}.stars span:nth-child(1){
          top: 10%;    left: 10%;    --d: 10s;}.stars span:nth-child(2){
          top: 20%;    left: 20%;    --d: 6s;}.stars span:nth-child(3){
          top: 30%;    left: 30%;    --d: 5s;}.stars span:nth-child(4){
          top: 10%;    margin-left: 40%;    --d: 4s;}.stars span:nth-child(5){
          top: 40%;    left: 60%;    --d: 7s;}.stars span:nth-child(6){
          top: 30%;    left: 80%;    --d: 9s;}.stars span:nth-child(7){
          top: 40%;    left: 20%;    --d: 8s;}.stars span:nth-child(8){
          top: 50%;    left: 40%;    --d: 15s;}.stars span:nth-child(9){
          top: 60%;    left: 70%;    --d: 14s;}.stars span:nth-child(10){
          top: 80%;    left: 50%;    --d: 11s;}.stars span:nth-child(11){
          top: 75%;    left: 23%;    --d: 20s;}.stars span:nth-child(12){
          top: 55%;    left: 4%;    --d: 24s;}.stars span:nth-child(13){
          top: 36%;    left: 26%;    --d: 8s;}.stars span:nth-child(14){
          top: 93%;    left: 18%;    --d: 3s;}.stars span:nth-child(15){
          top: 58%;    left: 68%;    --d: 2.6s;}.stars span:nth-child(16){
          top: 64%;    left: 86%;    --d: 1.5s;}.stars span:nth-child(17){
          top: 6%;    left: 78%;    --d: 3.5s;}.stars span:nth-child(18){
          top: 13%;    left: 58%;    --d: 6s;}.stars span:nth-child(19){
          top: 50%;    left: 50%;    --d: 8s;}.stars span:nth-child(20){
          top: 88%;    left: 88%;    --d: 7s;}