SOURCE

 <div class="sun">
    <div class="sun-light sl1"></div>
    <div class="sun-light sl2"></div>
    <div class="sun-light sl3"></div>
    <div class="sun-light sl4"></div>
    <div class="sun-light sl5"></div>
    <div class="sun-light sl6"></div>
    <div class="sun-light sl7"></div>
    <div class="sun-light sl8"></div>
  </div>

/* // css */
    .sun {
      margin: 200px;
      width: 200px;
      height: 200px;
      border-radius: 50%;
      background: red;
      box-shadow: 0 0 21px #fe9e9e;
      position: relative;
    }
  /* // ::before & ::after  辅助 */
    .sun::before {
      width: 0;
      height: 500px;
      content: '';
      border-left: 1px solid blue;
      position: absolute;
      top: -150px;
      left: 100px;
      z-index: 100;
      transform: rotate(45deg);
    }
    .sun::after {
      width: 500px;
      height: 0;
      content: '';
      border-top: 1px solid blue;
      position: absolute;
      top: 100px;
      left: -150px;
      z-index: 100;
      transform: rotate(45deg);
    }
  /* // 光线的宽高据 sun-body 而动 */
    .sun-light {
      width: 100px;
      height: 6px;
      background: yellow;
      position: absolute;
      left: 0;
      top: 0;
    }
    .sl1 {
      left: 50px;
      top: -58px;
      transform: rotate(90deg);
    }
    .sl2 {
      top: -14px;
      left: 160px;
      transform: rotate(-45deg);
    }
    .sl3 {
      top: 97px;
      left: 205px;
    }
    .sl4 {
      top: 206px;
      left: 160px;
      transform: rotate(45deg);
    }
    .sl5 {
      top: 252px;
      left: 50px;
      transform: rotate(90deg);
    }
    .sl6 {
      top: 206px;
      left: -60px;
      transform: rotate(-45deg);
    }
    .sl7 {
      top: 97px;
      left: -105px;
    }
    .sl8 {
      top: -14px;
      left: -60px;
      transform: rotate(45deg);
    }