Как написать 2 класса в HTML
<div class="nav nav-centered nav-reversed navbar navigation-block"></div>
Odd Octopus
<div class="nav nav-centered nav-reversed navbar navigation-block"></div>
To specify multiple classes, separate the class names with a space,
e.g. <span class="classA classB">.
This allows you to combine several CSS classes for one HTML element.
<div class = "first">
<div class = "second">
<element>
</div>
</div>