JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <link rel="stylesheet" href="css/normalize.css">
  <link rel="stylesheet" href="css/style.css">
  <link href="https://fonts.googleapis.com/css?family=Oswald:300,400" rel="stylesheet">
  <!--<link rel="shortcut icon" href="favicon.ico">-->
  <title>BlueSquare</title>
</head>
<body>
<div class="upperline"></div>
<div class="container">
<header class="main-header">
<div class="top-header clearfix">
  <div class="logo"></div>
  <form action="#" class="search">
    <input type="search" name="search" value="" placeholder="Search">
    <input type="submit" name="submit" value="go">
  </form>
</div>
  <ul class="main-menu">
    <li class="active"><a href="#">Home</a></li>
    <li><a href="#">about us</a></li>
    <li><a href="#">services</a></li>
    <li><a href="#">partners</a></li>
    <li><a href="#">customers</a></li>
    <li><a href="#">projects</a></li>
    <li><a href="#">careers</a></li>
    <li><a href="#">contacts</a></li>
  </ul>
</header>
  <div class="slider">
    <div class="slider-wrap">
      <div class="slider-item">
        <img src="img/banner-fall-cabin-docks-final-960x280.jpg" alt="слайдер">
        </div>
      <div class="slider-info">
        <h2 class="big-text">Fusce vitae nibh quis diam fermentum</h2>
        <p class="small-text">Etiam adipiscing ultricies commodo.</p>
      </div>
    </div>
    <div class="slider-menu">
      <li class="active"><a href="#">Lorem Ipsum Dolop</a></li>
      <li><a href="#">Ultricies Pellentesque</a></li>
      <li><a href="#">Aliquam ipsum</a></li>
      <li><a href="#">Nullam sed mauris ut</a></li>
    </div>
  </div>
<main class="main-content">
  <div class="line line1">
    <div class="box box1">
      <p class="box-header"><span>About WhiteSquare</span></p>
    <div class="box-content">
      <figure class="box-image">
      <img src="http://placehold.it/140x140" alt="#" width="140"...

CSS

/*RESET*/
html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed,
figure, figcaption, footer, header, hgroup,
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
	margin: 0;
	padding: 0;
	border: 0;
	font-size: 100%;
	font: inherit;
	vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure,
footer, header, hgroup, menu, nav, section {
	display: block;
}
body {
	line-height: 1;
}
ol, ul {
	list-style: none;
}
blockquote, q {
	quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
	content: '';
	content: none;
}
table {
	border-collapse: collapse;
	border-spacing: 0;
}
a {
	text-decoration: none;
}
/*СОХРАНЯЕМ ПРОПОРЦИИ*/
img {
    max-width: 100%;
    height: auto;
}
body {

	font-family: 'Oswald', sans-serif;
}
/*ЦЕНТРОВЩИК */
.container {
  width: 960px;
  margin: 0 auto;
}
.clearfix::after{
  content: '';
  display: table;
  clear: both;
}
/*header*/
.main-header {
  padding-top: 23px;
}
.top-header {
  margin-bottom: 23px;
}
.upperline,
.main-footer {
  background-color: #7e7e7e;
}
.upperline {
  height: 5px;
}
.logo {
  float: left;
  width: 161px;
  height: 38px;
  background: url('../img/Logo.png')
}
.search {
  float: right;
  font-size: 0px;
}
.search input {
	vertical-align: bottom;
}
.top-header input[type="search"] {
    background-color: #f3f3f3;
    border: 1px solid #e7e7e7;
    border-right: none;
    padding: 9px;
    font-family: 'Tahoma', sans-serif;
    font-size: 12px;
    color: #b2b2b2;
		outline: none;
}

.top-header input[type="submit"] {
  width: 42px;
	height: 34px;
  text-align: center;
  font-size: 14px;
	line-height:...