/* 变量与基础重置 */
        :root {
            --ucchpb-primary: #FF7139;
            --ucchpb-secondary: #0060DF;
            --ucchpb-accent: #9059FF;
            --ucchpb-dark: #20123A;
            --ucchpb-light: #F9F9FB;
            --ucchpb-text: #15141A;
            --ucchpb-white: #FFFFFF;
            --ucchpb-gap-base: 8px;
            --ucchpb-transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
            --ucchpb-container-width: 1320px;
        }

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

        body {
            font-family: "Inter", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--ucchpb-light);
            color: var(--ucchpb-text);
            line-height: 1.6;
            overflow-x: hidden;
            word-break: keep-all;
        }

        /* 布局通用类 */
        .ucchpb-container {
            max-width: var(--ucchpb-container-width);
            margin: 0 auto;
            padding: 0 24px;
            width: 100%;
        }

        .ucchpb-flex {
            display: flex;
            flex-wrap: wrap;
        }

        .ucchpb-flex-item {
            min-width: 0;
        }

        .ucchpb-section {
            padding: 96px 0;
            position: relative;
        }

        /* 导航栏 */
        .ucchpb-header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(20px);
            border-bottom: 1px solid rgba(0,0,0,0.05);
            transition: var(--ucchpb-transition);
        }

        .ucchpb-header.ucchpb-scrolled {
            box-shadow: 0 10px 30px rgba(0,0,0,0.08);
            background: rgba(255, 255, 255, 0.95);
        }

        .ucchpb-nav-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 80px;
            max-width: var(--ucchpb-container-width);
            margin: 0 auto;
            padding: 0 24px;
        }

        .ucchpb-logo {
            flex-shrink: 0;
        }

        .ucchpb-logo img {
            height: 40px;
            width: auto;
            display: block;
        }

        .ucchpb-menu {
            display: flex;
            list-style: none;
            gap: 32px;
            align-items: center;
        }

        .ucchpb-menu-item a {
            text-decoration: none;
            color: var(--ucchpb-text);
            font-weight: 500;
            font-size: 1rem;
            transition: var(--ucchpb-transition);
            position: relative;
            padding: 8px 0;
        }

        .ucchpb-menu-item a:hover {
            color: var(--ucchpb-primary);
        }

        .ucchpb-menu-item.ucchpb-active a {
            color: var(--ucchpb-secondary);
        }

        .ucchpb-menu-item.ucchpb-active a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 3px;
            background: var(--ucchpb-secondary);
            border-radius: 2px;
        }

        /* Hero 区域 - 非对称动态布局 */
        .ucchpb-hero {
            padding-top: 160px;
            padding-bottom: 80px;
            background: radial-gradient(circle at 90% 10%, rgba(255, 113, 57, 0.1) 0%, transparent 40%),
                        radial-gradient(circle at 10% 90%, rgba(0, 96, 223, 0.1) 0%, transparent 40%);
        }

        .ucchpb-hero-grid {
            display: grid;
            grid-template-columns: 1.2fr 0.8fr;
            gap: 64px;
            align-items: center;
        }

        .ucchpb-hero-content {
            word-break: break-word;
        }

        .ucchpb-hero-title {
            font-size: clamp(2.5rem, 5vw + 1rem, 4.5rem);
            line-height: 1.1;
            font-weight: 800;
            margin-bottom: 24px;
            color: var(--ucchpb-dark);
            letter-spacing: -1px;
        }

        .ucchpb-hero-subtitle {
            font-size: clamp(1.1rem, 2vw + 0.5rem, 1.4rem);
            color: #555;
            margin-bottom: 40px;
            max-width: 600px;
        }

        .ucchpb-download-hub {
            background: var(--ucchpb-white);
            padding: 40px;
            border-radius: 24px;
            box-shadow: 0 40px 80px rgba(0,0,0,0.06);
            border: 1px solid rgba(0,0,0,0.03);
            display: inline-flex;
            flex-direction: column;
            gap: 24px;
            position: relative;
            z-index: 2;
        }

        .ucchpb-btn-main {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            background: linear-gradient(135deg, var(--ucchpb-primary), #FF9442);
            color: white;
            padding: 20px 48px;
            border-radius: 12px;
            font-size: 1.25rem;
            font-weight: 700;
            text-decoration: none;
            box-shadow: 0 15px 30px rgba(255, 113, 57, 0.3);
            transition: var(--ucchpb-transition);
        }

        .ucchpb-btn-main:hover {
            transform: translateY(-5px);
            box-shadow: 0 20px 40px rgba(255, 113, 57, 0.4);
        }

        .ucchpb-hero-image-wrapper {
            position: relative;
        }

        .ucchpb-hero-img {
            width: 100%;
            height: auto;
            border-radius: 32px;
            box-shadow: 0 50px 100px rgba(0,0,0,0.1);
            transform: perspective(1000px) rotateY(-5deg);
        }

        /* 隐私盾牌区域 */
        .ucchpb-privacy-section {
            background-color: var(--ucchpb-dark);
            color: var(--ucchpb-white);
            border-radius: 64px 64px 0 0;
            margin-top: -32px;
        }

        .ucchpb-section-header {
            text-align: center;
            margin-bottom: 64px;
        }

        .ucchpb-section-title {
            font-size: clamp(2rem, 3vw, 3rem);
            margin-bottom: 16px;
        }

        .ucchpb-grid-3 {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
            gap: 32px;
        }

        .ucchpb-card {
            background: rgba(255, 255, 255, 0.05);
            padding: 48px;
            border-radius: 24px;
            border: 1px solid rgba(255, 255, 255, 0.1);
            transition: var(--ucchpb-transition);
        }

        .ucchpb-card:hover {
            background: rgba(255, 255, 255, 0.08);
            transform: translateY(-10px);
            border-color: var(--ucchpb-primary);
        }

        .ucchpb-card-icon {
            font-size: 40px;
            margin-bottom: 24px;
            display: block;
            color: var(--ucchpb-primary);
        }

        .ucchpb-card-title {
            font-size: 1.5rem;
            margin-bottom: 16px;
            font-weight: 700;
        }

        .ucchpb-card-list {
            list-style: none;
            margin-top: 16px;
        }

        .ucchpb-card-list li {
            margin-bottom: 8px;
            font-size: 0.95rem;
            opacity: 0.8;
            padding-left: 20px;
            position: relative;
        }

        .ucchpb-card-list li::before {
            content: '✓';
            position: absolute;
            left: 0;
            color: var(--ucchpb-primary);
        }

        /* 移动端下载区域 */
        .ucchpb-mobile-section {
            background: var(--ucchpb-white);
        }

        .ucchpb-split-layout {
            display: flex;
            align-items: center;
            gap: 80px;
        }

        .ucchpb-split-image {
            flex: 1;
            min-width: 0;
        }

        .ucchpb-split-image img {
            width: 100%;
            border-radius: 24px;
        }

        .ucchpb-split-content {
            flex: 1;
            min-width: 0;
        }

        .ucchpb-qr-box {
            display: flex;
            align-items: center;
            gap: 24px;
            margin-top: 32px;
            padding: 24px;
            background: var(--ucchpb-light);
            border-radius: 16px;
            width: fit-content;
        }

        .ucchpb-qr-placeholder {
            width: 120px;
            height: 120px;
            background: #ddd;
            display: flex;
            align-items: center;
            text-align: center;
            font-size: 12px;
            border-radius: 8px;
        }

        /* 开发者版本入口 */
        .ucchpb-dev-edition {
            background: linear-gradient(rgba(0,0,0,0.8), rgba(0,0,0,0.8)), url('images/developer_edition_logo.jpg');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 120px 0;
            text-align: center;
            border-radius: 32px;
            margin: 0 24px 96px;
        }

        .ucchpb-btn-outline {
            display: inline-block;
            border: 2px solid white;
            color: white;
            padding: 16px 40px;
            border-radius: 12px;
            text-decoration: none;
            font-weight: 600;
            margin-top: 32px;
            transition: var(--ucchpb-transition);
        }

        .ucchpb-btn-outline:hover {
            background: white;
            color: var(--ucchpb-dark);
        }

        /* 底部 */
        .ucchpb-footer {
            background: #15141A;
            color: #AAA;
            padding: 80px 0 40px;
        }

        .ucchpb-footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 48px;
            margin-bottom: 64px;
        }

        .ucchpb-footer-brand-name {
            color: white;
            font-size: 1.5rem;
            font-weight: 800;
            margin-bottom: 24px;
            display: block;
        }

        .ucchpb-footer-col h4 {
            color: white;
            margin-bottom: 24px;
            font-size: 1.1rem;
        }

        .ucchpb-footer-links {
            list-style: none;
        }

        .ucchpb-footer-links li {
            margin-bottom: 12px;
        }

        .ucchpb-footer-links a {
            color: #AAA;
            text-decoration: none;
            transition: var(--ucchpb-transition);
        }

        .ucchpb-footer-links a:hover {
            color: var(--ucchpb-primary);
        }

        .ucchpb-footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.05);
            padding-top: 40px;
            text-align: center;
            font-size: 0.9rem;
        }

        /* 响应式调整 */
        @media (max-width: 1024px) {
            .ucchpb-hero-grid {
                grid-template-columns: 1fr;
                text-align: center;
            }
            .ucchpb-hero-subtitle {
                margin-left: auto;
                margin-right: auto;
            }
            .ucchpb-hero-img {
                transform: none;
                max-width: 600px;
                margin: 0 auto;
            }
            .ucchpb-footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }

        @media (max-width: 768px) {
            .ucchpb-nav-container {
                height: 70px;
            }
            .ucchpb-menu {
                display: none; /* 简化处理，实际可添加汉堡菜单 */
            }
            .ucchpb-section {
                padding: 64px 0;
            }
            .ucchpb-split-layout {
                flex-direction: column;
                gap: 40px;
            }
            .ucchpb-footer-grid {
                grid-template-columns: 1fr;
            }
        }