el-tooltip加背景图

      <li class="preferred"><el-checkbox v-model="queryForm.topicAccepted">文案xxx</el-checkbox><el-tooltipplacement="top"popper-class="hover-tooltip":hide-after="0"><div slot="content" class="preferred-tip-content"><p>提示内容xxxxx</p></div><i class="el-icon-warning-outline preferred-tip-icon"></i></el-tooltip></li><style lang="scss" scoped>.preferred-tip-icon {margin-left: 5px;font-size: 14px;color: #999999;}
</style><style lang="scss">
.prefered-tip.is-dark {padding: 11px 15px;background-color: #262626;box-shadow: 0px 0px 10px 0px rgba(0, 0, 0, 0.5);font-size: 14px;color: #cccccc;line-height: 1;.preferred-tip-content {display: flex;align-items: center;&::before {content: "";width: 64px;height: 22px;display: block;background: url("@/assets/images/media/preferred.png") no-repeat center /100% 100%;margin-right: 5px;}}
}
</style>

如图所示：