修改el-date-picker宽度

  <div style="width: 100%">
                        <el-date-picker
                                style="width:100%"
                                v-model="value"
                                type="datetimerange"
                                start-placeholder="开始日期"
                                end-placeholder="结束日期"
                                :default-time="['12:00:00']"
                                value-format="yyyy-MM-dd HH:mm:ss"
                                @change="getTime"
                        >
                        </el-date-picker>
                    </div>