SOURCE

    <div class="box">
      <div class="ul">
        <li class="parent">四川区域</li>
        <li class="child">四川一区</li>
        <li class="child">四川二区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
        <li class="child">四川三区</li>
      </div>
    </div>

    .box {
      position: relative;
      left: 20%;
      top: 100px;
    }

    .box .ul {
      list-style: none;
      position: relative;
    }

    .box .ul::before {
      content: "";
      position: absolute;
      width: 1px;
      background: #000;
      left: -10px;
      height: calc(100% - 20px);
      top: 10px;
    }

    .box li {
      position: relative;
    }
    .box li::before {
      content: "";
      position: absolute;
      width: 10px;
      height: 10px;
      background: #f00;
      top: 50%;
      transform: translateY(-50%);
      left: -15px;
    }

    .box li.child::after {
      content: "";
      position: absolute;
      width: 24px;
      height: 1px;
      background: #000;
      top: 50%;
      transform: translateY(-50%);
      left: -39px;
      top: 12px;
    }

    .box .child {
      margin-left: 30px;
    }