JSFiddle - React, Tailwind, and code Playground

HTML

<textarea>Lorem Ipsum dolor sit atem</textarea>
<input type="text" value="Lorem Ipsum dolor sit atem" />
<p>Lorem Ipsum dolor sit atem</p>

CSS

::-moz-selection {
    background: black;
    color: white;
}

::-webkit-selection {
    background: black;
    color: white;
}

.selected {
    background: black;
    color: white;
}

JavaScript

$(document).ready(function(){
    
    $('textarea').focus(function() {
        
        $(this).addClass('selected');
    
    });
    
    $('input').focus(function() {
    
        $(this).addClass('selected');
    
    });
        
    $('textarea').blur(function() {
        
        $(this).removeClass('selected');
        
    });
        
    $('input').blur(function() {
        
        $(this).removeClass('selected');
        
    });

});