<el-cascader popper-class="myCascader" ></el-cascader>

.myCascader {
  .el-radio__inner {
    top: -18px;
    left: -19px;
    border-radius: 0;
    border: 0;
    width: 170px;
    height: 34px;
    background-color: transparent;
    cursor: pointer;
    box-sizing: border-box;
    position: absolute;
  }
  .el-radio__input.is-checked .el-radio__inner {
      background: transparent;
  }
}

    cascaderChange (val) {
      console.log(val)
      if (this.$refs.myCascader) {
        // this.$refs.myCascader.closeVisible = false
        this.$refs.myCascader.dropDownVisible  = false
      }
    },