body, html {
  height: 100%;
  margin: 0;
  background: #f8f9fa;
  font-family: Arial, sans-serif;
}
.chat-container {
  max-width: 600px;
  margin: 2rem auto;
  display: flex;
  flex-direction: column;
  height: 80vh;
  border: 1px solid #ddd;
  border-radius: .5rem;
  background: #fff;
  overflow: hidden;
}
.chat-header {
  background: #0d6efd;
  color: #fff;
  padding: 1rem;
  text-align: center;
  font-size: 1.25rem;
}
.chat-messages {
  flex: 1;
  padding: 1rem;
  overflow-y: auto;
  background: #e9ecef;
}
.message {
  display: flex;
  align-items: flex-start;
  margin-bottom: .75rem;
}
.message img {
  border-radius: 50%;
  width: 32px;
  height: 32px;
  margin-right: .5rem;
}
.message .content {
  background: #fff;
  padding: .5rem 1rem;
  border-radius: .5rem;
  box-shadow: 0 2px 4px rgba(0,0,0,.1);
}
.message .meta {
  font-size: .75rem;
  color: #666;
  margin-bottom: .25rem;
}
.chat-input {
  display: flex;
  border-top: 1px solid #ddd;
}
.chat-input input {
  flex: 1;
  border: none;
  padding: 1rem;
  font-size: 1rem;
}
.chat-input button {
  border: none;
  background: #0d6efd;
  color: #fff;
  padding: 1rem 1.5rem;
  cursor: pointer;
}