JSFiddle - React, Tailwind, and code Playground

HTML

<body>
	
	
	<header>

			
	<!-- Menu-->
		
		<div class="menu">
		
		<br/>
			<ul>
				<li>
					<a href="index.html">Strona Główna</a>
				</li>
				<li>
					<a href="podstrona/podstrona_1.html">Podstrona pierwsza</a>
				</li>
				<li>		
					<a href="podstrona/podstrona_2.html">Ogłoszenie</a>
				</li>	
				<li>
					<a href="">Kontakt</a>
				</li>
			</ul>	
		
		</div>
		
	<!--Top bar-->
		<div id="top">
		</div>	
		
	</header>
	
	

	
	
	<!-- Main container-->
	
		<div class="main-container">
			<!--opcjonalnie-->
			<aside class="sidebar_left">
			</aside>
			
			<div class="main-content">
				<div class="article_1">
					<h3>ASAP FERG LYRICS</h3>
						
							"Fuck Out My Face"<br/>
					(feat. B-Real, Onyx & Aston Matthews)<br/>
					<br/>
							[Verse 2: Ferg] (...)<br/>
					<br/>
				
				</div>
				
				<div class="article_2">
					<h2>Nagłówek</h2>
				</div>
				
				<div class="article_3">
					<h2>Nagłówek</h2>
				</div>
				
				<div class="article_4">
					<h2>Nagłówek</h2>
				</div>
				
				<div class="article_5">
					<h2>Nagłówek</h2>
				</div>
				
				<div class="article_6">
					<h2>Nagłówek</h2>
				</div>
				
				<div class="article_7">
					<h2>Nagłówek</h2>
				</div>
			</div>
			
			 
			<aside class="sidebar_right">prawa kolumna
			</aside>
		
		</div>

		
		
</body>

CSS

body {
	color:#EEEEEE;
}


.menu {
	background-color: #666666;
	height: 55px;
	margin: 0 auto;
	
}


#top {
	background-color: #333333;
	height: 100px;
	width: 1200px;
	margin: 0 auto;
	
	
}


ul, ul li {
	display: inline;
	
}

ul {
	margin: 0 auto;
	margin-left: 280px;
}

ul li {
	
	margin-right: 1px;
}

ul a:link, ul a:visited {
	text-decoration: none;
	background-color: #ccc;
	color: #000;
	padding: 5px 10px;
	border: 1px solid #888;
	font-family: Tahoma;	
}

ul a:hover {
	background-color: #fff;
	
}




.main-container {
	width: 1200px;
	margin: 0 auto;
	
}	


.sidebar_right {
	width: 300px;
	height: 1450px;
	background-color: #333333;
	margin-top: 5px;
}


.main-content {
	width: 900px;
	height: 1500px;
	background-color: #111111;
}




.main-content,
.sidebar_right {
	float: left;
}


.article_1, .article_2, .article_3, .article_4, .article_5, .article_6, .article_7 {
	border: 1px solid #888;
	padding: 0px 20px;
	margin-top: 5px;
	margin-right: 20px;
	background-color: #333333;
	height: 200px;
	font-color: white;
}