Check out example codes for "conditional style angular". It will help you in understanding the concepts better.

Code Example 1

// ngStyle (conditional Style)
<div *ngFor='let [data] of [dataArray]; let i=index;'>
  <h2 [style.background]="i>1? 'green': 'red'"> {{i}} {{data.title}} </h2>

  </div> 

//if the index of the element is 1 or 0, the background will be red, if it is over 1 the background will be green

Code Example 2

<div [ngStyle]="{'color':employee.country === 'India' ? 'orange' : 'red' }"></<div>

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