index.css

*{
	margin: 0; 
	padding: 0; 
	list-style: none;
}
.container{
	width:600px;
	 margin: 20px auto;
}
h2{
	text-align: center;
}
#ul1{
	position: relative;
	width:600px; 
	height: 400px; 
	overflow:auto; 
	border: 1px solid #b3c7e1; 
	padding: 10px; 
	margin: 10px 0;
}
#ul1 li{
	float:left; 
	width:350px;
	margin: 15px 0; 
	padding: 10px; 
	background-color: #EEEEEE;
}
#ul1 li.self{
	float: right;
	background-color: #0b97c4
}
#ul1 li.who,#ul1 li.typing{
	width: 95%; 
	text-align: center; 
	font-size: 14px; 
	font-weight: bold; 
	color: #19469D; 
	background: none; 
	margin: 0;
}
#ul1 li.typing{
	color:blue;
}
#ul1 li.who_online {
	position: absolute;
	bottom: 0;
}
#ul1 li span{
	float: right; 
	font-size: 14px;
}
#ul1 li p{
	padding: 10px 5px;
}
textarea{
	width: 80%; 
	float: left;
}
#btn1{
	width: 15%; 
	margin-top: 10px; 
	height: 60px; 
	float: right;
}