body {
  font-family: 'Roboto', sans-serif;
  background: linear-gradient(to right, #74ebd5, #ACB6E5);
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
}

.chat-container {
  width: 420px;
  height: 600px;
  background: white;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.header {
  padding: 18px;
  background: #4FC3F7;
  color: white;
  font-size: 20px;
  text-align: center;
  font-weight: bold;
}

.chat-box {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
  background: #f5f7fa;
}

.bot-message, .user-message {
  background: #e1f5fe;
  padding: 12px 16px;
  margin: 10px 0;
  border-radius: 10px;
  max-width: 80%;
  animation: fadeIn 0.3s ease-in-out;
}

.user-message {
  background: #c5e1a5;
  align-self: flex-end;
  text-align: right;
}

.input-box {
  display: flex;
  border-top: 1px solid #ddd;
}

input {
  flex: 1;
  border: none;
  padding: 16px;
  font-size: 16px;
  outline: none;
}

button {
  background: #4FC3F7;
  color: white;
  border: none;
  padding: 0 24px;
  font-size: 16px;
  cursor: pointer;
  transition: background 0.3s ease;
}

button:hover {
  background: #03a9f4;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(5px); }
  to { opacity: 1; transform: translateY(0); }
}