:root {
            --primary-color: #07c160;
            --success-hover: #05964d;
            --avatar-size: 40px;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
        }

        body {
            background: #e1e1e1;
            height: 100vh;
            display: flex;
            flex-direction: column;
        }

        .chat-container {
           flex: 1;
    max-width: 800px;
    margin: 20px auto;
    width: 100%;
    padding: 0 15px;
    overflow-y: auto;
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    overscroll-behavior: contain;
    overflow-anchor: none;
    
    /* 新增隐藏滚动条 */
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none;  /* IE/Edge */
            
        }
.chat-container::-webkit-scrollbar {
    width: 0;
    height: 0;
}
        .message {
            margin: 15px 0;
            display: flex;
            align-items: flex-start;
            animation: fadeIn 0.3s ease;
        }

        .message .avatar {
            width: var(--avatar-size);
            height: var(--avatar-size);
            border-radius: 5px;
            flex-shrink: 0;
        }

        .system-msg {
            flex-direction: row;
        }

        .system-msg .avatar {
            margin-right: 12px;
            background: url('../img/vxtx.jpeg') no-repeat center/cover;
        }

        .user-msg {
            flex-direction: row-reverse;
        }

        .user-msg .avatar {
            margin-left: 12px;
            background: url('../img/yhtx.png') no-repeat center/cover;
        }

        .system-msg .bubble {
            background: white;
            border-radius: 5px 18px 18px 5px;
            max-width: 75%;
            padding: 12px 16px;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
        }

        .user-msg .bubble {
            background: #9eea6a;
            border-radius: 18px 5px 5px 18px;
            max-width: 75%;
            padding: 12px 16px;
        }

        .options {
            margin-top: 10px;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-around;
            gap: 8px;
        }

        .option-btn {
            font-size: 1rem;
            box-sizing: border-box;
            word-break: break-all;
            padding: 8px 15px;
            border: none;
            border-radius: 15px;
            background: var(--primary-color);
            color: white;
            cursor: pointer;
            transition: all 0.2s;
            width: calc(50% - 4px);
            touch-action: manipulation;
        }

        .option-btn:hover {
            background: var(--success-hover);
        }

        .option-btn:active,
        #completeBtn:active {
            transform: scale(0.95);
            transition: transform 0.1s;
        }

        #completeBtn {
            font-size: 1rem;
            width: 100%;
            padding: 12px 30px;
            background: var(--primary-color);
            color: white;
            border: none;
            border-radius: 5px;
            cursor: pointer;
            margin: 20px auto;
            display: block;
            touch-action: manipulation;
        }

        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: translateY(10px);
            }

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .loading-dots::after {
            content: '';
            display: inline-block;
            width: 1em;
            text-align: left;
            animation: loading 1s infinite;
        }

        @keyframes loading {
            0% {
                content: '';
            }

            33% {
                content: '.';
            }

            66% {
                content: '..';
            }

            100% {
                content: '...';
            }
        }

        .banner img {
            width: 100%;
            pointer-events: none;
            display: block;
            border: 0;
            margin: 0;
            loading: lazy;
        }

   @media screen and (min-width:760px)and (max-width:1920px) {
      body {
          width: 640px;
        margin: 0 auto;
      }
  }