Css的ul的li水平居中自适应样式问题

Question

遇到一个样式问题Css
当前盒子水平居中
ul中有6个li里边有div包着img
最外边的盒子div有一个背景图，背景图一个长方形刚好包着 ul
当浏览器宽度变窄的时候 ul 里边的元素都没有自适应缩放。
心累。
贴代码求指教。

<div  class="Startthechallengee">
              <div>
                <ul>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/txnk.png">
                    </div>
                  </li>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/PS5.png">
                    </div>
                  </li>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/pgsj.png">
                    </div>
                  </li>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/bx.png">
                    </div>
                  </li>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/cm.png">
                    </div>
                  </li>
                  <li>
                    <div>
                      <img src="~/assets/img/blrgb/xdch.png">
                    </div>
                  </li>
                </ul>
              </div>
            </div>

.Startthechallengee{
  left: 12%;
  position: absolute;
  top: 71%;
  background-image: url("~/assets/img/blrgb/jpdbt.png");
  background-repeat: no-repeat;
  background-size: 90% 90%;
  width: 80%;
  height: 16%;
}
.Startthechallengee img{
  width: 180px;
  height: 150px;
}
.Startthechallengee ul{
  position: absolute;
  top: -18%;
  left: -6%;
  /*position: relative;*/
  display: inline-block;
  margin-right: 30px
}
.Startthechallengee li{
  position: relative;
  cursor: pointer;
  display: inline-block;
  text-align: center;
  margin: 0 90px;
  color: #dcdcdc;
  vertical-align: middle;
}
.Startthechallengee img{
  /*width: 1200px;*/
  /*height: 170px;*/
  /*position: absolute;*/
  /*left:18%;*/
  /*top: 70%;*/
}

Answer 1

加一个flex
.Startthechallengee>div{display:flex}