element-ui 自定义单元格字体颜色样式

<el-table-column label="状态" prop="State">
    <template slot-scope="scope">
        <font v-if="scope.row.State === 'online'">在线</font>
        <font v-else-if="scope.row.State === 'offline'" color="red">离线</font>
        <font v-else color="blue">未知</font>
    </template>
</el-table-column>