#webmail{
display:grid;
grid-template-columns:200px 300px 1fr;
gap:10px;
font-family:Arial;
}

#accounts{
border-right:1px solid #ccc;
}

#inbox{
border-right:1px solid #ccc;
overflow:auto;
height:600px;
}

#reader{
padding:10px;
}

#composer textarea{
width:100%;
height:120px;
}