*{
	margin: 0px;
	padding: 0px;
	border: 0px;
	font-family: "Times New Roman", Times, serif;
}
body{
	padding-top: 30px;
	background: rgb(30, 30, 30);
	color: white;
}
#screen{
	margin: auto;
	width: 95%;
	border-radius: 25px 25px 25px 25px;
}
header{
	text-align: center;
	background: rgb(15, 15, 255);
	height: 55px;
	border-radius: 25px 25px 0px 0px;
}
h1{
	margin-top: -7px;
	font-weight: bold;
	font-size: 50px;
	width: 60%;
	float: left;
}
nav{
	background: rgb(0, 0, 200);
	height: 40px;
}
button{
	font-size: 15px;
	margin-top: 8px;
	margin-left: 3px;
	height: 25px;	
	padding-left: 5px;
	padding-right: 5px;
}
#main{
	text-align: center;
	background: rgb(15, 15, 255);
	width: 60%;
	height: 500px;
	float: left;
}
#sub{
	text-align: center;
	background: rgb(15, 0, 255);
	width: 40%;
	height: 500px;
	float: left;
}
footer{
	text-align: center;
	height: 55px;	
	background: rgb(0, 0, 200);	
	border-radius: 0px 0px 25px 25px;
	clear:left;
}
li{
	display: inline;
	list-style-type: none;
}
.left_button{
	border-radius: 10px 0px 0px 10px;
	
}
.right_button{
	border-radius: 0px 10px 10px 0px;
}