body{font-family:Arial,Helvetica,sans-serif;margin:0;background:#f5f7fb}
.app header{background:#0b5fff;color:#fff;padding:12px 20px;display:flex;justify-content:space-between;align-items:center}
.app header h1{margin:0;font-size:18px}
main{display:flex;gap:12px;padding:12px}
.pane{width:220px;background:#fff;padding:10px;border-radius:6px;box-shadow:0 2px 6px rgba(0,0,0,0.06)}
.chat{flex:1;display:flex;flex-direction:column}
.messages{flex:1;background:#fff;padding:12px;border-radius:6px;overflow:auto;height:60vh;box-shadow:0 2px 6px rgba(0,0,0,0.04)}
.composer{display:flex;flex-direction:column;padding-top:8px}
textarea{width:100%;height:80px;padding:8px;border-radius:6px;border:1px solid #ddd}
.actions{display:flex;gap:8px;justify-content:flex-end;padding-top:8px}
.message{padding:8px;margin-bottom:6px;border-radius:6px}
.message.user{background:#eaf2ff}
.message.assistant{background:#eefaf1}