JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html lang="ru">
<head>
	<meta charset="UTF-8">
	<link href='https://fonts.googleapis.com/css?family=Roboto:400,300,300italic,400italic,500,500italic,700,700italic&subset=latin,cyrillic' rel='stylesheet' type='text/css'>
    <link rel="stylesheet" href="css/style.css">
    <link rel="stylesheet" type="text/css" href="css/symbols-nerds.css">
	<title>Nerds</title>
</head>
<body>
<!-- HEADER -->
	<header>
		<div class="container">
			<div class="logo">
				<a href="index.html"><img src="../nerd/img/logo.png" alt="logo"></a>
			</div>
			<ul class="menu">
				<li><a href="#">Студия</a></li>
				<li><a href="#">Клиенты</a></li>
				<li><a href="#">Магазин</a></li>
				<li><a href="#">Контакты</a></li>
			</ul>
			<div class="basket">
				<a href="#" class="basket-enter"><i class="icon-basket active"></i> Корзина</a>
			</div>
		</div>

<!-- SLIDER -->
	
	<div class="slider">
        <input type="radio" id="btn-1" name="toggle" checked>
        <input type="radio" id="btn-2" name="toggle">
        <input type="radio" id="btn-3" name="toggle">
        <div class="slider-controls">
          <label for="btn-1"></label>
          <label for="btn-2"></label>
          <label for="btn-3"></label>
        </div>
        <div class="slides">
          <div class="slide">
            <div class="slide-text">
              <div class="slide-title">Долго, дорого, скрупулезно</div>
              <p>Математически выверенный дизайн<br>
  			  для вашего сайта или мобильного приложения.</p>
              <a class="btn" href="#">Узнать больше</a>
            </div>
          </div>
          <div class="slide">
            <div class="slide-text">
              <div class="slide-title">Дорого, скрупулезно</div>
              <p>Математически выверенный дизайн<br>
  			  для вашего сайта или мобильного приложения.</p>
              <a class="btn" href="#">Узнать больше</a>
            </div>
          </div>
          <div class="slide">
            <div...

CSS

html, body{
    padding:0;
    margin:0;
    font-family: 'Roboto', sans-serif;
}

.container {
	width: 900px;
    padding: 0 10px;
    min-height: 110px;
    margin: 0 auto;
}

.clearfix {
	content: '';
	display: table;
	clear: both;
}

/* HEADER */

header {
	min-width: 900px;
	padding-top: 30px;
	background: #eeeeee;
}

.logo {
	float: left;
	width: 140px;
	height: 55px;
	margin-right: 180px;
}

ul.menu {
	margin-top: 10px;
}

.menu {
	float: left;
	padding: 0;
	margin-bottom: 45px;
}

.menu li {
	display: inline-block;
	list-style: none;
	margin-top: 15px;
	margin-right: 40px;
}

.menu a {
	display: block;
	font: 14px/30px 'Roboto', sans-serif;
	font-weight: 500;
	color: #000;
	text-transform: uppercase;
	text-decoration: none;
}

.basket-enter {
	float: right;
	position: relative;
	margin-top: 25px;
	margin-bottom: 10px;
	padding-left: 30px;
	font: 14px/30px 'Roboto', sans-serif;
	font-weight: 500;
	color: #000;
	text-transform: uppercase;
	text-decoration: none;
}

.menu a:hover, .basket-enter:hover {
	color: #fb565a;
}

.menu a:active, .basket-enter:active {
	color: #cbcbcb;
}

li.active, .basket-enter.active {
	color: #000;
	border: 2px solid #fb565a;
}


/* HEADER END */

/* SLIDER */

.slider{
    position: relative;
    width: 880px;
    height: 310px;
    margin: 0 auto;
}
.slider input[type=radio] {
    position: absolute;
    opacity: 0;
}
.slider-controls{
    position: absolute;
    bottom: 95px;
    left: 50%;
    width: 200px;
    height: 10px;
    margin-left: -100px;
    text-align: center;
    z-index: 1000;
}
.slider-controls label{
    display: inline-block;
    width: 4px;
    height: 4px;
    margin: 0 3px;
    background: white;
    border: 3px solid white;
    vertical-align: top;
    border-radius: 50%;
    cursor: pointer;
}
#btn-1:checked ~ .slider-controls label[for="btn-1"],
#btn-2:checked ~ .slider-controls label[for="btn-2"],
#btn-3:checked ~ .slider-controls label[for="btn-3"] { 
    background: #c1c1c1;
}
.slide{
    position:...

JavaScript

<script>

    		var link=document.querySelector('.send-us-btn');
			var popup=document.querySelector('.letter-popup');
			var close=document.querySelector('.letter-popup-close');
			var login=document.querySelector('.name-field');

			link.addEventListener('click', function(event) {
			    event.preventDefault();
			    popup.classList.add('letter-popup-show');
			    login.focus();
			}, false);
			close.addEventListener('click', function(event) {
			    event.preventDefault();
			    popup.classList.remove('letter-popup-show');
			}, false);

			$(function() {
			    $( "#Slider1" ).slider({
					range: true,
					min: 0,
					max: 15000,
					values: [ 0, 3000 ],
					slide: function( event, ui ) {
						$(".min-price").val(ui.values[ 0 ]);
						$(".max-price").val(ui.values[ 1 ]);
					}
			    });

			    //radio
			    $('.radio-btn').on('click', function() {
			    	$('.radio-btn').removeClass('checked');
			    	$(this).addClass('checked');
			    });

			    //checkbox
			    $('.checkbox-btn').on('click', function() {
			    	if($(this).hasClass('checked')) {
			    		$(this).removeClass('checked');
			    	} else {
			    		$(this).addClass('checked');
			    	}
			    });
			});

    </script>