Несколько Ngclass
<section [ngClass]="{'class1':condition1, 'class2': condition2, 'class3':condition3}" >
Marton
<section [ngClass]="{'class1':condition1, 'class2': condition2, 'class3':condition3}" > <!-- notice expression1 used twice -->
<div ng-class="{class1 : expression1, class2 : expression1}">
Hello World!
</div>