.standalone-shell { width:min(460px,calc(100vw - 28px)); height:min(720px,calc(100vh - 28px)); margin:14px auto; }
.standalone-shell .chat-card { width:100%; height:100%; min-height:0; }
@media (max-width:500px) { .standalone-shell { width:100%; height:100vh; margin:0; } .standalone-shell .chat-card { border-radius:0; } }