Example of CSS code

/*body was created*/
body{
    background-color:#FFFF99
{

/*conatiner was createed*/
#container{
     width: 80%;
     margin-left: auto;
     margin-right: auto;
}

/* Header was created*/
header{
	margin-top: 10px;
	margin-bottom: 20px;
	background-color: #FFFFFF;
	border-radius: 10px;
	box-shadow: 12px 12px 12px #404040;
	text-align: center;
}