body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background: #f0f2f5; margin: 0; display: flex; align-items: center; justify-content: center; height: 100vh; }
.auth-container, .chat-wrapper { background: white; padding: 20px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,0.1); width: 350px; }
input { width: calc(100% - 20px); padding: 10px; margin-bottom: 10px; border: 1px solid #ddd; border-radius: 4px; }
button { width: 100%; padding: 10px; background: #0084ff; color: white; border: none; border-radius: 4px; cursor: pointer; }
button:hover { background: #0073e6; }
#messages { height: 300px; overflow-y: auto; border: 1px solid #eee; margin-bottom: 10px; padding: 5px; display: flex; flex-direction: column; }
.msg-item { background: #e7f3ff; padding: 8px; border-radius: 15px; margin: 4px 0; align-self: flex-start; max-width: 80%; }