apps/kirjs/src/app/modules/cellular-automation/rule3/rule4/rule4.component.html
<div class="wrapper">
<div class="rule" *ngFor="let row of before; let in = index">
<div style="display: flex;">
<div class="cell" *ngFor="let i of row" [class.active]="i == 1"></div>
</div>
<div class="cell after" [class.active]="after[in]"></div>
</div>
</div>