1. The sum of the flex-basis in the table must equal to 100%
2. Directly use the *ngIf in the div tag instead of use the ng-template
3. If using flex-basis: row (default value when define display: flex), vertical-align (justify-content: center), horizontal align (align-items: center)
4. If using flex-basis: column vertical-align (align-items: center), horizontal align (justify-content: center)
5. No need to add padding-left or padding-right if the column is horizontal align center