* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #1a1a2e;
  color: #fff;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.chat-container {
  width: 90%;
  max-width: 600px;
  height: 90vh;
  background: #16213e;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

header {
  padding: 15px;
  background: #0f3460;
  text-align: center;
  font-size: 1.2rem;
  font-weight: bold;
}

#chat-messages {
  flex: 1;
  padding: 15px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.message {
  max-width: 80%;
  padding: 10px 15px;
  border-radius: 10px;
  word-wrap: break-word;
}

.message.user {
  align-self: flex-end;
  background: #4a90e2;
}

.message.bot {
  align-self: flex-start;
  background: #2a2a4a;
}

#chat-form {
  padding: 15px;
  background: #0f3460;
  display: flex;
  gap: 10px;
}

#model {
  padding: 10px;
  border: none;
  border-radius: 6px;
  background: #1a1a2e;
  color: #fff;
  cursor: pointer;
}

#user-input {
  flex: 1;
  padding: 10px;
  border: none;
  border-radius: 6px;
  background: #1a1a2e;
  color: #fff;
  outline: none;
}

#user-input::placeholder {
  color: #666;
}

button {
  padding: 10px 20px;
  border: none;
  border-radius: 6px;
  background: #4a90e2;
  color: #fff;
  cursor: pointer;
  font-weight: bold;
}

button:hover {
  background: #357abd;
}

button:disabled {
  background: #666;
  cursor: not-allowed;
}