My purpose is click a button and show a div with some text, but there are a lot of buttons in the page.I need to recalculate top value for my component according to browser resize. I'm a newbie and I don't know how I can do this. I do this (angular)

<div [top]="top">

in my ts:

click(event){
this.top=(event['Y']);
}

The problem is that when resize browser and click on the one button the div is not open when I want. I think there is some formula: event.y-event.screenY but I don't find Anyone can help me?