Ember : Hook for css property change

I have to render a lot of divs into DOM. So, what I did is I render the first 5 elements into the DOM first after that I render every 10 divs with 300ms interval period.

The problem is when I change into display: block I need to change something in the component. So, I try to use didRender hook for that.

Code is below

didRender() {
   if(this.element.offsetParent) {
      this.set('myvar', true);
   }
} 

But it's not working perfectly. Anyone please suggest me which is the best way to do this.

_Thanks in Advance.