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

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 300vh;
        }

        .content {
            max-width: 800px;
            margin: 0 auto;
            padding: 40px 20px;
            padding-bottom: 140px; /* 给底部按钮留出更多空间 */
            color: white;
        }

        .content h1 {
            text-align: center;
            margin-bottom: 30px;
            font-size: 2.5rem;
        }

        .content p {
            line-height: 1.8;
            margin-bottom: 20px;
            font-size: 1.1rem;
        }

        .section {
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            border-radius: 15px;
            padding: 30px;
            margin-bottom: 30px;
        }

        /* ===== 自适应宽度悬浮按钮样式 ===== */
        .floating-bar {
            position: fixed;
            left: 50%;
            transform: translateX(-50%);
            bottom: 30px;
            /* 自适应宽度核心：使用 padding 代替固定 width */
            padding: 0 45px; /* 左右内边距确保最小宽度，并控制内容间距 */
            height: 60px;
            background: linear-gradient(135deg, #ffd700, #ffb347);
            border-radius: 25px;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            box-shadow: 0 4px 15px rgba(238, 90, 36, 0.4);
            transition: all 0.3s ease;
            z-index: 1000;
            border: none;
            /* 自适应宽度核心：设置最小宽度，确保不压缩过度 */
            min-width: 120px;
        }

        /* 悬停展开效果：通过增加内边距实现，宽度自适应 */
        .floating-bar:hover {
            padding: 0 80px;
            background: linear-gradient(135deg, #feca57, #ff9f43);
            box-shadow: 0 6px 25px rgba(255, 159, 67, 0.5);
        }

        .floating-bar span {
            color: white;
            font-size: 30px;
            font-weight: 550;
            letter-spacing: 1px;
            white-space: nowrap; /* 防止文字换行，保持一行 */
        }

        .floating-bar .arrow {
            margin-left: 8px;
            font-size: 25px;
            transition: transform 0.3s ease;
        }

        .floating-bar:hover .arrow {
            transform: translateX(5px);
        }

        .floating-bar:active {
            transform: translateX(-50%) scale(0.97);
        }

        /* 双侧脉冲动画 */
        .floating-bar::before,
        .floating-bar::after {
            content: '';
            position: absolute;
            top: 50%;
            transform: translateY(-50%);
            width: 8px;
            height: 8px;
            background: rgba(255, 255, 255, 0.5);
            border-radius: 50%;
            animation: pulse 2s infinite;
        }

        .floating-bar::before {
            left: 20px;
        }

        .floating-bar::after {
            right: 20px;
            animation-delay: 1s;
        }

        @keyframes pulse {
            0% {
                transform: translateY(-50%) scale(1);
                opacity: 0.8;
            }
            100% {
                transform: translateY(-50%) scale(2.5);
                opacity: 0;
            }
        }

        /* 提示文字在按钮上方 */
        .tooltip {
            position: absolute;
            left: 50%;
            bottom: calc(100% + 15px);
            transform: translateX(-50%);
            background: rgba(0, 0, 0, 0.8);
            color: white;
            padding: 8px 15px;
            border-radius: 5px;
            font-size: 14px;
            white-space: nowrap;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
        }

        .tooltip::after {
            content: '';
            position: absolute;
            top: 100%;
            left: 50%;
            transform: translateX(-50%);
            border: 6px solid transparent;
            border-top-color: rgba(0, 0, 0, 0.8);
        }

        .floating-bar:hover .tooltip {
            opacity: 1;
            visibility: visible;
        }

        /* 移动端适配 */
        @media (max-width: 768px) {
            .floating-bar {
                padding: 0 25px;
                height: 40px;
                bottom: 20px;
                border-radius: 20px;
                min-width: 100px;
            }

            .floating-bar:hover {
                padding: 0 35px;
            }

            .floating-bar span {
                font-size: 10px;
            }

            .floating-bar .arrow {
                font-size: 14px;
                margin-left: 5px;
            }

            .tooltip {
                display: none;
            }

            .content {
                padding-bottom: 100px;
            }
        }

        /* 滚动条样式 */
        ::-webkit-scrollbar {
            width: 8px;
        }

        ::-webkit-scrollbar-track {
            background: #f1f1f1;
        }

        ::-webkit-scrollbar-thumb {
            background: #888;
            border-radius: 4px;
        }

        ::-webkit-scrollbar-thumb:hover {
            background: #555;
        }
    </style>