* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  html,
  body {
    height: 100%;
  }
  
  body {
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: Arial, sans-serif;
    background-color: #222;
  }
  
  .chat-container {
    display: flex;
    flex-direction: column;
    max-width: 800px;
    width: 100%;
    height: 80%;
    border-radius: 10px;
    overflow: hidden;
    background-color: #333;
    box-shadow: 0px 5px 10px rgba(0, 0, 0, 0.3);
  }
  
  .chat-header {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 60px;
    background-color: #111;
    color: #fff;
    font-size: 24px;
    text-shadow: 1px 1px 1px rgba(0, 0, 0, 0.2);
  }
  
  .chat-header h1 {
    margin: 0;
  }
  
  .chat-messages {
    display: flex;
    flex-direction: column;
    flex: 1;
    padding: 20px;
    overflow-y: scroll;
    scrollbar-width: thin;
    scrollbar-color: #e6e6e6 #f7f7f7;
  }
  
  .message {
    display: flex;
    align-items: flex-start;
    margin-bottom: 20px;
    max-width: 80%;
    padding: 10px;
    border-radius: 10px;
    font-size: 16px;
    box-shadow: 0px 2px 5px rgba(0, 0, 0, 0.2);
  }
  
  .message.sent {
    margin-left: auto;
    background-color: #007bff;
    color: #fff;
  }
  
  .message.received {
    background-color: #fff;
    color: #222;
  }
  
  .avatar {
    width: 40px;
    height: 40px;
    margin-right: 10px;
    border-radius: 50%;
    background-color: #444;
  }
  
  .content {
    display: flex;
    flex-direction: column;
  }
  
  .sender {
    font-weight: bold;
    margin-bottom: 5px;
  }
  
  .text {
    word-wrap: break-word;
  }
  
  .chat-input {
    display: flex;
    align-items: center;
    padding: 10px;
    background-color: #111;
  }
  
  .chat-input input[type="text"] {
    flex: 1;
    padding: 10px;
    border: none;
    border-radius: 20px;
    background-color: #444;
    color: #fff;
    font-size: 16px;
  }
  
  .chat-input button {
    padding: 10px 20px;
    margin-left: 10px;
    border: none;
    border-radius: 20px;
    background-color: #007bff;
    color: #fff;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.2s ease;
  }
  
  .chat-input button:hover {
    background-color: #0069d9;
  }