angular ngclass

<div [ngStyle]="{'background-color':person.country === 'UK' ? 'green' : 'red' }"></<div>[ngClass]="{'my-class': step=='step1'}"      
        content_copy
      
      <some-element [ngClass]="'first second'">...</some-element>

<some-element [ngClass]="['first', 'second']">...</some-element>

<some-element [ngClass]="{'first': true, 'second': true, 'third': false}">...</some-element>

<some-element [ngClass]="stringExp|arrayExp|objExp">...</some-element>

<some-element [ngClass]="{'class1 class2 class3' : true}">...</some-element>
    <div [ngClass]="{ 
'green': number > 5,
  'red': number <= 5,
}" ></div>
//if the number is over 5, the class 'green' will be added to the div.
//if the number is below or equal 5, the class 'red' will be added to the div.[ngClass]="{'my-class': step=='step1', 'my-class2':step=='step2' }"[class.my-class]="step=='step1'"