body {
  font-family: Arial, sans-serif;
  background-color: #f4f4f4;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh; /* use min-height for better mobile behavior */
  margin: 0;
  padding: 10px; /* small padding on mobile */
}

.chat-container {
  background: #fff;
  padding: 20px;
  width: 100%;
  max-width: 500px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
  border-radius: 10px;
  display: flex;
  flex-direction: column;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  margin-bottom: 15px;
  max-height: 400px;
}
