JSFiddle - React, Tailwind, and code Playground

HTML

<input id="b1" type="button" value="Hello world" />
<input id="b2" type="button" value="Blubba blib" />
<input id="b3" type="button" value="Bl" />
<input id="b4" type="button" value="Blubba 55" />

CSS

input[type='button'] {
    padding: 3px 10px 4px;
}

JavaScript

$('input:button').click(function() {
    var w = $(this).outerWidth();

    $(this).css({
        'font-weight': 'bold',
        'width': w
    }).siblings().css({
        'width': 'auto',
        'font-weight': 'normal'
    });
});