看代码
前端代码为

					<div class="main_table t_btn2">
					// 设置表格背景色,字体颜色以及字体大小
                            <el-table :header-cell-style="{backgroundColor:'transparent',color:'#ffffff',fontSize:'15px',textAlign:'center'}"
                                      :cell-style="{color: '#fff',backgroundColor:'transparent',fontSize:'13px',textAlign:'center'}"
                                      :row-style="{color: '#fff',backgroundColor:'transparent',fontSize:'13px',textAlign:'center'}"
                                      :data="ipTableData"
                                      max-height="340"
                                style="width: 100%">
                                <el-table-column
                                    prop="ip"
                                    label="IP"
                                    :show-overflow-tooltip="true">
                                    <template slot="header" slot-scope="scope">
                                        <p style="cursor: pointer;" @click="showContent('ip')">IP</p>
                                    </template>
                                </el-table-column>
                                <el-table-column
                                    prop="domain"
                                    :show-overflow-tooltip="true">
                                    <template slot="header" slot-scope="scope">
                                        <p style="cursor: pointer;" @click="showContent('ip')">域名</p>
                                    </template>
                                </el-table-column>
                                <el-table-column
                                    prop="address"
                                    label="来源地址">
                                    <template slot="header" slot-scope="scope">
                                        <p style="cursor: pointer;" @click="showContent('ip')">来源地址</p>
                                    </template>
                                </el-table-column>
                                <el-table-column
                                    prop="type"
                                    label="欺诈类型">
                                    <template slot="header" slot-scope="scope">
                                        <p style="cursor: pointer;" @click="showContent('ip')">欺诈类型</p>
                                    </template>
                                </el-table-column>
                                <el-table-column
                                    prop="count"
                                    label="拦截次数">
                                    <template slot="header" slot-scope="scope">
                                        <p style="cursor: pointer;" @click="showContent('ip')">拦截次数</p>
                                    </template>
                                </el-table-column>
                            </el-table>
                        </div>

css样式代码

	// .t_btn2为你的上级父元素class名称 
	// 由于是只在本页面修改, 所以必须要用 /deep/ 或者 >>> 才能生效  /deep/ 是深度选择器,可自行百度了解更多
    .t_btn2 /deep/  .el-table, .el-table__expanded-cell {
        background-color: transparent;
    }
    .t_btn2 /deep/ .el-table tr {
        background-color: transparent!important;
    }
    .t_btn2 /deep/  .el-table--enable-row-transition .el-table__body td, .el-table .cell{
        background-color: transparent;
    }
    .t_btn2 /deep/  .el-table__row>td{
        border: none;
    }
    /* 清除底部横线 */
    .el-table::before {
        height: 0px;
    }

最终效果为