#chat-container { max-width: 400px; margin: 1em auto; font-family: sans-serif; }
#chat-log { border: 1px solid #ddd; height: 300px; overflow-y: auto; padding: 0.5em; }
.user-msg { text-align: right; margin: 0.5em 0; }
.bot-msg  { text-align: left; margin: 0.5em 0; background: #f7f7f7; padding: 0.3em 0.5em; border-radius: 4px; }
.error    { color: red; }
#chat-input { width: 75%; padding: 0.5em; }
#chat-form button { padding: 0.5em 1em; }