JSFiddle - React, Tailwind, and code Playground

HTML

<table border="1">
    <tbody>
        <tr class="headerRow">
            <th class="item-name">Наименование</th>
            <th class="item-quantity">Количество</th>
            <th class="item-price">Цена</th>
        </tr>
            <tr class="itemRow row-0 odd">
            <td class="item-name">Menu Item 1</td>
            <td class="item-quantity">1</td>
            <td class="item-price">15.00&nbsp;РУБ.</td>
        </tr>
    </tbody>
</table>

<form class="form-contact" method="post" name="formContact" id="formContact" novalidate>
			<div class="input-container">
				<input type="text" name="firstName" id="firstName" placeholder="Имя*" value="Вася" required />
			</div>

			<div class="input-container">
				<input type="text" name="lastName" id="lastName" placeholder="Фамилия*" value="Петрович" required />
			</div>
    
			<div class="footer">
				<button id="submit" type="submit" name="submit">Отправить</button>
			</div>
		</form>

JavaScript

$(function() {
    $('#formContact').validate({
		errorPlacement: $.noop,
		rules: {
			firstName: {
				required: true
			},
			lastName: {
				required: true
			}
		},
		submitHandler: function(form) {
			console.log("SUBMIT");

			$(form).ajaxSubmit({
				type:"POST",
				data: $(form).serialize(),
				url:"send.php",
				success: function() {
					console.log("YES");
					$('#formContact :input').attr('disabled', 'disabled');
					$('#formContact').fadeTo( "slow", 0.15, function() {
						$(this).find(':input').attr('disabled', 'disabled');
					});
				},
				error: function() {
					console.log("NO");
					$('#formContact').fadeTo( "slow", 0.15, function() {
					});
				}
			});
		}
	});
});