body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background: #1f1f1f;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.chat-container {
  width: 100%;
  max-width: 400px;
  height: 90vh;
  background: #2a2a2a;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.chat-header {
  padding: 16px;
  background: #333;
  text-align: center;
  font-weight: bold;
  border-bottom: 1px solid #444;
}

.chat-box {
  flex: 1;
  padding: 16px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.chat-message {
  background: #3a3a3a;
  padding: 10px 14px;
  border-radius: 16px;
  max-width: 70%;
  align-self: flex-start;
}

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

form {
  display: flex;
  border-top: 1px solid #444;
}

input[type="text"] {
  flex: 1;
  padding: 14px;
  background: #1f1f1f;
  border: none;
  color: white;
}

button {
  background: #4a90e2;
  color: white;
  border: none;
  padding: 0 20px;
  cursor: pointer;
}