菜单管理，图标超出范围添加滚动条

src/views/modules/sys/menu-add-or-update.vue

              placement="bottom-start"
              trigger="click"
              popper-class="mod-menu__icon-popover">
              <div class="mod-menu__icon-list">
                <el-button
                  v-for="(item, index) in iconList"
                  :key="index"
                  @click="iconActiveHandle(item)"
                  :class="{ 'is-active': item === dataForm.icon }">
                  <icon-svg :name="item"></icon-svg>
                </el-button>
              <div class="mod-menu__icon-inner">
                <div class="mod-menu__icon-list">
                  <el-button
                    v-for="(item, index) in iconList"
                    :key="index"
                    @click="iconActiveHandle(item)"
                    :class="{ 'is-active': item === dataForm.icon }">
                    <icon-svg :name="item"></icon-svg>
                  </el-button>
                </div>
              </div>
            </el-popover>
            <el-input v-model="dataForm.icon" v-popover:iconListPopover :readonly="true" placeholder="菜单图标名称" class="icon-list__input"></el-input>
      }
    }
    &__icon-popover {
      max-width: 370px;
      width: 458px;
      overflow: hidden;
    }
    &__icon-inner {
      width: 478px;
      max-height: 258px;
      overflow-x: hidden;
      overflow-y: auto;
    }
    &__icon-list {
      max-height: 180px;
      width: 458px;
      padding: 0;
      margin: -8px 0 0 -8px;
      > .el-button {