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

    /* 确保文字链接可以被正常点击和选择 */
    a[href] {
        cursor: pointer;
        user-select: text;
        pointer-events: auto;
    }

    body {
        font-family: 'PingFang SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        min-height: 100vh;
    }

    .footer {
        background: #ffffff;
        border-top: 1px solid rgba(0, 0, 0, 0.1);
        margin-top: auto;
    }

    .footer-features {
        background: #ffffff;
        border-bottom: 1px solid rgba(0, 0, 0, 0.05);
        padding: 40px 0;
    }

    .footer-features-container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 24px;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 40px;
        align-items: center;
    }

    .feature-item {
        display: flex;
        align-items: center;
        gap: 16px;
        padding: 20px 0;
    }

    .feature-icon {
        width: 48px;
        height: 48px;
        flex-shrink: 0;
        object-fit: contain;
        user-select: none;
        pointer-events: none;
    }

    .feature-content h4 {
        font-size: 16px;
        font-weight: 600;
        color: #333;
        margin-bottom: 6px;
        line-height: 1.3;
    }

    .feature-content p {
        font-size: 14px;
        color: #666;
        line-height: 1.4;
        margin: 0;
    }

    .footer-container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 40px 24px 0;
    }

    .footer-content {
        display: grid;
        grid-template-columns: 200px repeat(auto-fit, minmax(180px, 1fr));
        gap: 32px;
        margin-bottom: 40px;
    }

    @media (min-width: 1024px) {
        .footer-content {
            grid-template-columns: 200px 1fr 1fr 1fr 1fr 2fr;
        }
    }

    .footer-brand {
        display: flex;
        flex-direction: column;
        align-items: flex-start;
    }

    .footer-logo {
        display: flex;
        align-items: center;
        margin-bottom: 20px;
    }

    .footer-logo img {
        height: 45px;
        width: auto;
        max-width: 200px;
        object-fit: contain;
        user-select: none;
        pointer-events: none;
    }



    .footer-social {
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 24px;
        margin-bottom: 0;
    }

    .social-item {
        display: flex;
        flex-direction: column;
        align-items: center;
        text-decoration: none;
        color: #666;
        font-size: 12px;
        transition: all 0.3s ease;
        position: relative;
        cursor: default;
        user-select: none;
        pointer-events: none;
    }

    .qr-code {
        width: 80px;
        height: 80px;
        background: white;
        border: 1px solid rgba(0, 0, 0, 0.1);
        border-radius: 8px;
        margin-bottom: 8px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 10px;
        color: #999;
        transition: all 0.3s ease;
        position: relative;
        cursor: default;
        user-select: none;
        pointer-events: none;
        overflow: hidden;
    }

    .qr-code table {
        width: 85% !important;
        height: 85% !important;
        border-collapse: collapse !important;
        border-radius: 4px;
        overflow: hidden;
        margin: auto;
    }

    .qr-code img {
        max-width: 85%;
        max-height: 85%;
        border-radius: 4px;
        margin: auto;
        display: block;
    }

    /* 悬停效果：当前二维码放大，其他变透明 */
    .footer-social:hover .social-item:not(:hover) .qr-code::after {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(255, 255, 255, 0.7);
        border-radius: 8px;
        transition: all 0.3s ease;
        pointer-events: none;
    }

    .social-item:hover .qr-code {
        transform: scale(1.15);
        box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    }

    .footer-section {
        display: flex;
        flex-direction: column;
    }

    .footer-section-title {
        font-size: 16px;
        font-weight: 600;
        color: #333;
        margin-bottom: 20px;
        padding-bottom: 8px;
        border-bottom: 2px solid rgba(26, 115, 232, 0.1);
    }

    .footer-links {
        display: flex;
        flex-direction: column;
        gap: 12px;
    }

    .footer-link {
        color: #333;
        text-decoration: none;
        font-size: 14px;
        transition: color 0.3s ease;
        display: flex;
        align-items: center;
        gap: 6px;
        cursor: pointer;
        user-select: text;
    }

    .footer-link:hover {
        color: #1a73e8;
    }

    .footer-link-hot::after {
        content: 'HOT';
        background: #ff4757;
        color: white;
        font-size: 10px;
        padding: 2px 4px;
        border-radius: 2px;
        font-weight: 500;
    }

    .footer-link-new::after {
        content: 'NEW';
        background: #2ed573;
        color: white;
        font-size: 10px;
        padding: 2px 4px;
        border-radius: 2px;
        font-weight: 500;
    }

    .footer-contact {
        background: none;
        border-radius: 0;
        padding: 0;
        border: none;
        margin-bottom: 0;
    }

    .contact-item {
        display: flex;
        align-items: flex-start;
        gap: 8px;
        margin-bottom: 12px;
        font-size: 14px;
        color: #666;
    }

    .contact-item:last-child {
        margin-bottom: 0;
    }

    .contact-label {
        font-weight: 500;
        color: #666;
        min-width: 60px;
    }

    .contact-value {
        color: #333;
        text-decoration: none;
        cursor: pointer;
        user-select: text;
    }

    .contact-value:hover {
        color: #1a73e8;
        text-decoration: none;
    }

    .footer-social-section {
        margin-top: 24px;
        margin-bottom: 0;
    }

    .footer-social-title {
        display: none;
    }

    .footer-bottom {
        border-top: 1px solid rgba(0, 0, 0, 0.1);
        padding: 24px 0;
        text-align: center;
        background: rgba(248, 250, 252, 0.8);
    }

    .footer-bottom-content {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 24px;
    }

    .footer-copyright {
        color: #333;
        font-size: 13px;
        line-height: 1.6;
        margin-bottom: 16px;
    }

    .footer-links-bottom {
        display: flex;
        justify-content: center;
        align-items: center;
        gap: 20px;
        flex-wrap: wrap;
        margin-bottom: 16px;
    }

    .footer-link-bottom {
        color: #333;
        text-decoration: none;
        font-size: 13px;
        transition: color 0.3s ease;
        cursor: pointer;
        user-select: text;
    }

    .footer-link-bottom:hover {
        color: #1a73e8;
        text-decoration: none;
    }

    .footer-certificates {
        display: flex;
        justify-content: center;
        align-items: center;
        gap: 24px;
        flex-wrap: wrap;
        color: #666;
        font-size: 12px;
        line-height: 1.5;
    }

    .certificate-link {
        color: #333;
        text-decoration: none;
        transition: color 0.3s ease;
        cursor: pointer;
        user-select: text;
    }

    .certificate-link:hover {
        color: #1a73e8;
        text-decoration: none;
    }

    /* 响应式设计 */
    @media (max-width: 768px) {
        .footer-features {
            padding: 30px 0;
        }

        .footer-features-container {
            padding: 0 16px;
            grid-template-columns: repeat(4, 1fr);
            gap: 8px;
        }

        .feature-item {
            padding: 16px 4px;
            gap: 8px;
            justify-content: center;
            text-align: center;
            flex-direction: column;
            align-items: center;
        }

        .feature-item .feature-content p {
            display: none;
        }

        .feature-content h4 {
            font-size: 12px;
            text-align: center;
            line-height: 1.2;
        }

        .feature-icon {
            width: 40px;
            height: 40px;
        }

        .footer-container {
            padding: 30px 16px 0;
        }

        .footer-content {
            grid-template-columns: 1fr;
            gap: 0;
            margin-bottom: 30px;
        }

        .footer-contact {
            margin-bottom: 0;
            background: #f8f9fa;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 20px;
        }

        .footer-section.expanded .footer-contact {
            max-height: 400px;
            padding: 12px 20px 16px 20px;
        }

        .footer-social-section {
            margin-top: 0;
            margin-bottom: 0;
            background: #f8f9fa;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 20px;
        }

        .footer-section.expanded .footer-social-section {
            max-height: 400px;
            padding: 12px 20px 16px 20px;
        }

        .footer-social {
            gap: 20px;
            margin-bottom: 0;
            justify-content: flex-start;
        }

        .qr-code {
            width: 70px;
            height: 70px;
        }

        .qr-code table {
            width: 80% !important;
            height: 80% !important;
        }

        .qr-code img {
            max-width: 80%;
            max-height: 80%;
        }

        .footer-brand {
            display: none;
        }

        .footer-section {
            background: white;
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            margin-bottom: 0;
        }

        .footer-section-title {
            text-align: left;
            margin-bottom: 0;
            padding: 16px 20px;
            cursor: pointer;
            position: relative;
            user-select: none;
            border-bottom: none;
            background: white;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }

        .footer-section-title::after {
            content: '';
            width: 6px;
            height: 6px;
            border-right: 1.5px solid currentColor;
            border-bottom: 1.5px solid currentColor;
            transform: rotate(45deg);
            transition: transform 0.3s ease;
            flex-shrink: 0;
        }

        .footer-section.expanded .footer-section-title::after {
            transform: rotate(225deg);
        }

        .footer-links {
            align-items: flex-start;
            gap: 0;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 20px;
            background: #f8f9fa;
        }

        .footer-section.expanded .footer-links {
            max-height: 400px;
            padding: 12px 20px 16px 20px;
        }

        .footer-link {
            padding: 8px 0;
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            width: 100%;
        }

        .footer-contact {
            text-align: left;
        }

        .footer-links-bottom {
            flex-direction: row;
            gap: 12px;
            justify-content: center;
            flex-wrap: wrap;
        }

        .footer-certificates {
            flex-direction: row;
            gap: 12px;
            text-align: center;
            justify-content: center;
            flex-wrap: wrap;
        }
    }

    @media (max-width: 640px) {
        .footer-features {
            padding: 20px 0;
        }

        .footer-features-container {
            padding: 0 12px;
            grid-template-columns: repeat(4, 1fr);
            gap: 4px;
        }

        .feature-item {
            padding: 12px 2px;
            gap: 6px;
            justify-content: center;
            text-align: center;
            flex-direction: column;
            align-items: center;
        }

        .feature-item .feature-content p {
            display: none;
        }

        .feature-content h4 {
            font-size: 11px;
            text-align: center;
            line-height: 1.2;
        }

        .feature-icon {
            width: 36px;
            height: 36px;
        }

        .feature-content h4 {
            font-size: 12px;
        }

        .feature-content p {
            font-size: 13px;
        }

        .footer-container {
            padding: 20px 12px 0;
        }

        .footer-content {
            gap: 0;
            margin-bottom: 20px;
        }

        .footer-section {
            background: white;
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            margin-bottom: 0;
        }

        .footer-section-title {
            font-size: 15px;
            text-align: left;
            margin-bottom: 0;
            padding: 14px 16px;
            cursor: pointer;
            position: relative;
            user-select: none;
            border-bottom: none;
            background: white;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }

        .footer-section-title::after {
            content: '';
            width: 6px;
            height: 6px;
            border-right: 1.5px solid currentColor;
            border-bottom: 1.5px solid currentColor;
            transform: rotate(45deg);
            transition: transform 0.3s ease;
            flex-shrink: 0;
        }

        .footer-section.expanded .footer-section-title::after {
            transform: rotate(225deg);
        }

        .footer-links {
            align-items: flex-start;
            gap: 0;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 16px;
            background: #f8f9fa;
        }

        .footer-section.expanded .footer-links {
            max-height: 400px;
            padding: 10px 16px 14px 16px;
        }

        .footer-link {
            font-size: 13px;
            padding: 6px 0;
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            width: 100%;
        }

        .qr-code {
            width: 60px;
            height: 60px;
        }

        .qr-code table {
            width: 80% !important;
            height: 80% !important;
        }

        .qr-code img {
            max-width: 80%;
            max-height: 80%;
        }

        .contact-item {
            font-size: 13px;
        }

        .footer-contact {
            margin-bottom: 0;
            background: #f8f9fa;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 16px;
        }

        .footer-section.expanded .footer-contact {
            max-height: 400px;
            padding: 10px 16px 14px 16px;
        }

        .footer-social-section {
            margin-top: 0;
            margin-bottom: 0;
            background: #f8f9fa;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 16px;
        }

        .footer-section.expanded .footer-social-section {
            max-height: 400px;
            padding: 10px 16px 14px 16px;
        }

        .footer-social {
            gap: 16px;
            margin-bottom: 0;
            justify-content: flex-start;
        }

        .footer-brand {
            display: none;
        }
    }

    /* AI云服务推广区域样式 */
    .ai-promotion-section {
        width: 100%;
        min-height: 200px;
        background-color: #f8f9fa;
        background-size: cover;
        background-position: center;
        background-repeat: no-repeat;
        display: flex;
        align-items: center;
        justify-content: center;
        position: relative;
        overflow: hidden;
        transition: background-image 0.5s ease;
    }

    .ai-promotion-section.bg-loaded {
        background-image: url('/web/default/img/promotion-bg.jpg');
    }

    .ai-promotion-loading {
        position: absolute;
        top: 50%;
        left: 50%; 
        transform: translate(-50%, -50%);
        z-index: 1;
        opacity: 1;
        transition: opacity 0.3s ease;
    }

    .ai-promotion-section.bg-loaded .ai-promotion-loading {
        opacity: 0;
        pointer-events: none;
    }

    .ai-loading-spinner {
        width: 40px;
        height: 40px;
        border: 3px solid rgba(26, 115, 232, 0.2);
        border-top: 3px solid #1a73e8;
        border-radius: 50%;
        animation: ai-spin 1s linear infinite;
    }

    @keyframes ai-spin {
        0% {
            transform: rotate(0deg);
        }

        100% {
            transform: rotate(360deg);
        }
    }

    .ai-promotion-section::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: linear-gradient(135deg, rgba(64, 224, 255, 0.1) 0%, rgba(138, 43, 226, 0.1) 100%);
        z-index: 1;
    }

    .ai-promotion-container {
        width: 100%;
        max-width: 1200px;
        padding: 40px 40px;
        position: relative;
        z-index: 2;
    }

    .ai-promotion-content {
        text-align: center;
        color: #333;
    }

    .ai-promotion-title {
        font-size: 32px;
        font-weight: 600;
        margin-bottom: 12px;
        color: #fff;
        line-height: 1.2;
    }

    .ai-highlight {
        color: #fff;
        font-weight: 700;
    }

    .ai-promotion-subtitle {
        font-size: 16px;
        color: #efefef;
        margin-bottom: 24px;
        font-weight: 400;
        line-height: 1.4;
    }

    .ai-promotion-action {
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 0;
        max-width: 200px;
        margin: 0 auto;
    }

    .ai-register-btn {
        width: 100%;
        max-width: 160px;
        height: 44px;
        padding: 0 24px;
        background: #fff;
        color: #1a73e8;
        border: none;
        border-radius: 22px;
        font-size: 14px;
        font-weight: 600;
        cursor: pointer;
        transition: all 0.3s ease;
        white-space: nowrap;
        box-shadow: 0 2px 8px rgba(66, 133, 244, 0.3);
        font-family: 'PingFang SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        margin: 0 auto;
    }

    .ai-register-btn:hover {
        background: #ebebeb;
        transform: translateY(-1px);
        box-shadow: 0 4px 12px rgba(66, 133, 244, 0.4);
    }

    .ai-register-btn:active {
        transform: translateY(0);
        box-shadow: 0 2px 6px rgba(66, 133, 244, 0.3);
    }

    /* 响应式设计 */
    @media (max-width: 768px) {
        .ai-promotion-container {
            padding: 30px 20px;
        }

        .ai-promotion-title {
            font-size: 24px;
            margin-bottom: 10px;
        }

        .ai-promotion-subtitle {
            font-size: 14px;
            margin-bottom: 20px;
        }

        .ai-promotion-action {
            max-width: 150px;
        }

        .ai-register-btn {
            max-width: 150px;
            height: 40px;
            font-size: 13px;
        }

        .ai-loading-spinner {
            width: 32px;
            height: 32px;
            border-width: 2px;
        }
    }

    @media (max-width: 480px) {
        .ai-promotion-container {
            padding: 20px 16px;
        }

        .ai-promotion-title {
            font-size: 20px;
        }

        .ai-promotion-subtitle {
            font-size: 12px;
            margin-bottom: 16px;
        }

        .ai-register-btn {
            max-width: 140px;
            height: 36px;
            font-size: 12px;
            padding: 0 20px;
        }

        .ai-loading-spinner {
            width: 28px;
            height: 28px;
            border-width: 2px;
        }
    }

    /* 懒加载样式 */
    .lazy-load {
        opacity: 0;
        transition: opacity 0.3s ease;
    }

    .lazy-load.loaded {
        opacity: 1;
    }

    .image-loader {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        display: flex;
        align-items: center;
        justify-content: center;
        background: rgba(248, 249, 250, 0.8);
        z-index: 1;
        transition: opacity 0.3s ease;
    }

    .image-loader.hidden {
        opacity: 0;
        pointer-events: none;
    }

    .loader-spinner {
        width: 24px;
        height: 24px;
        border: 2px solid #f3f3f3;
        border-top: 2px solid #4285f4;
        border-radius: 50%;
        animation: spin 1s linear infinite;
    }

    @keyframes spin {
        0% {
            transform: rotate(0deg);
        }

        100% {
            transform: rotate(360deg);
        }
    }