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

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #10b981;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --bg-color: #ffffff;
    --bg-light: #f9fafb;
    --bg-alt: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    --radius: 12px;
    --transition: all 0.25s ease;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    overflow-x: hidden;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 56px;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    list-style: none;
    padding: 0;
    margin: 0;
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow);
}

.nav-links.active {
    display: flex;
}

.nav-links li {
    border-bottom: 1px solid var(--border-color);
}

.nav-links li:last-child {
    border-bottom: none;
}

.nav-links a {
    display: block;
    padding: 14px 16px;
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.nav-links a:active {
    background: var(--bg-light);
    color: var(--primary-color);
}

.mobile-menu-btn {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    margin: -8px;
}

.mobile-menu-btn span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text-color);
    border-radius: 2px;
    transition: var(--transition);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

.hero {
    min-height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 80px 16px 40px;
}

.hero h1 {
    font-size: 2rem;
    margin-bottom: 12px;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1rem;
    opacity: 0.9;
    margin-bottom: 24px;
    line-height: 1.5;
}

.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 0.95rem;
    -webkit-tap-highlight-color: transparent;
}

.btn-primary {
    background: white;
    color: var(--primary-color);
}

.btn-primary:active {
    transform: scale(0.98);
    opacity: 0.9;
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:active {
    background: var(--primary-color);
    color: white;
}

.products {
    padding: 48px 0;
    background: var(--bg-light);
}

.section-title {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 8px;
    font-weight: 700;
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    margin-bottom: 32px;
    font-size: 0.95rem;
    padding: 0 16px;
}

.product-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 0 4px;
}

.product-card {
    background: white;
    border-radius: var(--radius);
    padding: 24px 20px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.product-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 16px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-alt);
}

.product-logo {
    width: 48px;
    height: 48px;
    object-fit: contain;
    border-radius: 50%;
}

.product-icon svg {
    width: 32px;
    height: 32px;
}

.product-icon.android {
    background: linear-gradient(135deg, #3ddc84 0%, #00a05a 100%);
    color: white;
}

.product-card h3 {
    font-size: 1.25rem;
    margin-bottom: 6px;
    font-weight: 600;
}

.product-tag {
    display: inline-block;
    background: var(--bg-alt);
    color: var(--text-light);
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 0.8rem;
    margin-bottom: 12px;
}

.product-card p {
    color: var(--text-light);
    margin-bottom: 16px;
    line-height: 1.6;
    font-size: 0.9rem;
}

.product-detail {
    padding: 48px 0;
}

.product-detail.alt-bg {
    background: var(--bg-light);
}

.detail-content {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.detail-content.reverse {
    flex-direction: column;
}

.product-badge {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 0.8rem;
    margin-bottom: 8px;
}

.detail-text h2 {
    font-size: 1.5rem;
    margin-bottom: 8px;
    font-weight: 700;
}

.detail-desc {
    font-size: 1rem;
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.6;
}

.feature-list {
    list-style: none;
    margin-bottom: 20px;
}

.feature-list li {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 10px;
    font-size: 0.95rem;
    line-height: 1.5;
}

.feature-icon {
    color: var(--secondary-color);
    font-weight: bold;
    flex-shrink: 0;
}

.qrcode-section {
    margin-top: 20px;
    text-align: center;
}

.qrcode-section p {
    margin-bottom: 8px;
    color: var(--text-light);
    font-size: 0.9rem;
}

.qrcode-img {
    width: 140px;
    height: 140px;
    border-radius: 8px;
}

.detail-image {
    display: flex;
    justify-content: center;
}

.phone-mockup {
    width: 180px;
    height: 360px;
    background: #1f2937;
    border-radius: 28px;
    padding: 12px;
    box-shadow: var(--shadow-lg);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.85rem;
}

.phone-screen-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 18px;
}

.about {
    padding: 48px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.about .section-title {
    color: white;
}

.about-content {
    max-width: 600px;
    margin: 0 auto;
}

.about-content p {
    font-size: 0.95rem;
    opacity: 0.9;
    margin-bottom: 12px;
    line-height: 1.6;
}

.stats {
    display: flex;
    justify-content: center;
    gap: 32px;
    margin-top: 32px;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 1.75rem;
    font-weight: 700;
}

.stat-label {
    opacity: 0.85;
    font-size: 0.85rem;
}

.contact {
    padding: 48px 0;
    text-align: center;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 24px;
    font-style: normal;
}

.contact-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 0.95rem;
    color: var(--text-color);
}

.contact-item a {
    color: var(--primary-color);
    text-decoration: none;
}

.contact-icon {
    font-size: 1.1rem;
}

.footer {
    background: var(--text-color);
    color: white;
    padding: 24px 0;
    text-align: center;
}

.footer-content {
    font-size: 0.85rem;
    opacity: 0.8;
}

.footer-content a {
    color: white;
    opacity: 0.8;
}

@media (min-width: 480px) {
    .container {
        padding: 0 24px;
    }

    .hero {
        padding: 100px 24px 60px;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .product-grid {
        gap: 20px;
    }

    .product-card {
        padding: 28px 24px;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .detail-text h2 {
        font-size: 1.75rem;
    }

    .phone-mockup {
        width: 200px;
        height: 400px;
    }
}

@media (min-width: 768px) {
    .nav {
        height: 64px;
    }

    .logo {
        font-size: 1.4rem;
    }

    .nav-links {
        display: flex;
        position: static;
        flex-direction: row;
        background: transparent;
        gap: 32px;
        border-bottom: none;
        box-shadow: none;
        padding: 0;
    }

    .nav-links li {
        border-bottom: none;
    }

    .nav-links a {
        padding: 0;
    }

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

    .mobile-menu-btn {
        display: none;
    }

    .hero {
        min-height: 80vh;
        padding-top: 64px;
    }

    .hero h1 {
        font-size: 3rem;
    }

    .hero-subtitle {
        font-size: 1.25rem;
    }

    .products {
        padding: 80px 0;
    }

    .section-title {
        font-size: 2rem;
    }

    .section-subtitle {
        font-size: 1.05rem;
    }

    .product-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 24px;
    }

    .product-card {
        padding: 32px;
    }

    .product-card h3 {
        font-size: 1.35rem;
    }

    .product-card p {
        font-size: 0.95rem;
    }

    .product-detail {
        padding: 80px 0;
    }

    .detail-content {
        flex-direction: row;
        align-items: center;
        gap: 48px;
    }

    .detail-content.reverse {
        flex-direction: row-reverse;
    }

    .detail-text {
        flex: 1;
    }

    .detail-image {
        flex: 1;
    }

    .detail-text h2 {
        font-size: 2rem;
    }

    .detail-desc {
        font-size: 1.1rem;
    }

    .phone-mockup {
        width: 240px;
        height: 480px;
        border-radius: 32px;
        padding: 14px;
    }

    .phone-screen,
    .phone-screen-img {
        border-radius: 20px;
    }

    .qrcode-section {
        text-align: left;
    }

    .about {
        padding: 80px 0;
    }

    .about-content p {
        font-size: 1.05rem;
    }

    .stats {
        gap: 48px;
    }

    .stat-number {
        font-size: 2.25rem;
    }

    .contact {
        padding: 80px 0;
    }

    .contact-info {
        flex-direction: row;
        gap: 48px;
    }
}

@media (min-width: 1024px) {
    .hero h1 {
        font-size: 3.5rem;
    }

    .hero-subtitle {
        font-size: 1.35rem;
    }

    .products {
        padding: 100px 0;
    }

    .section-title {
        font-size: 2.25rem;
    }

    .product-grid {
        gap: 32px;
    }

    .product-detail {
        padding: 100px 0;
    }

    .detail-content {
        gap: 64px;
    }

    .detail-text h2 {
        font-size: 2.25rem;
    }

    .phone-mockup {
        width: 280px;
        height: 560px;
        border-radius: 40px;
        padding: 16px;
    }

    .phone-screen,
    .phone-screen-img {
        border-radius: 26px;
    }

    .about {
        padding: 100px 0;
    }

    .contact {
        padding: 100px 0;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    
    * {
        animation: none !important;
        transition: none !important;
    }
}