JSFiddle - React, Tailwind, and code Playground

HTML

<img src="http://dummyimage.com/600x400/000fff/ff0000" width="600" height="400" id="1" />

<img src="http://dummyimage.com/200x300/000000/ffffff" width="200" height="300" id="1" />

CSS

.horizontal {
 border:3px solid #00ff00;   
}
.vertical {
 border:3px solid #ff0000;   
}

JavaScript

$('img').each(function() {
    if($(this).width() > $(this).height()) {
          $(this).addClass("horizontal"); 
        $(this).attr("title", "horizontal");
    } else {
        $(this).addClass("vertical");
        $(this).attr("title", "vertical");
    }        
});