body{

background:#111;
color:white;
font-family:sans-serif;

display:flex;
justify-content:center;
align-items:center;

height:100vh;

}

.chat{

width:450px;
background:#222;
padding:20px;
border-radius:10px;

}

#messages{

height:300px;
overflow:auto;
margin-bottom:10px;

}