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

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary: #64748b;
    --accent: #f59e0b;
    --dark: #0f172a;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --radius: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--gray-700);
    line-height: 1.6;
    background: var(--white);
}

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

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-100);
    transition: var(--transition);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--dark);
}

.logo-icon {
    width: 36px;
    height: 36px;
    color: var(--primary);
}

.brand-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-links a {
    text-decoration: none;
    color: var(--gray-600);
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

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

.nav-links a:hover::after {
    width: 100%;
}

.nav-about-wrapper {
    position: relative;
    display: inline-block;
}

.wechat-popup {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-10px);
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow-xl);
    padding: 16px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
    margin-bottom: 8px;
    white-space: nowrap;
}

.wechat-popup::before {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 50%;
    transform: translateX(-50%) rotate(45deg);
    width: 12px;
    height: 12px;
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    border-right: 1px solid var(--gray-200);
}

.wechat-popup img {
    width: 180px;
    height: auto;
    border-radius: 8px;
}

.wechat-popup span {
    font-size: 0.875rem;
    color: var(--gray-600);
    font-weight: 500;
}

.nav-about-wrapper:hover .wechat-popup {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

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

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--gray-700);
    transition: var(--transition);
}

.hero {
    padding: 160px 0 100px;
    background: linear-gradient(180deg, var(--gray-50) 0%, var(--white) 100%);
    overflow: hidden;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    max-width: 560px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.1;
    color: var(--dark);
    margin-bottom: 20px;
}

.brand-highlight {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 16px;
}

.hero-desc {
    font-size: 1.125rem;
    color: var(--gray-500);
    margin-bottom: 32px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--radius);
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--gradient);
    color: var(--white);
    box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.5);
}

.btn-secondary {
    background: var(--white);
    color: var(--gray-700);
    border: 2px solid var(--gray-200);
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.hero-visual {
    display: flex;
    justify-content: center;
}

.visual-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: 24px;
    width: 100%;
    max-width: 500px;
}

.visual-header {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #f59e0b; }
.dot.green { background: #22c55e; }

.visual-content {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 40px 30px;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.connection-line {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    gap: 20px;
}

.endpoint {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.endpoint svg {
    width: 48px;
    height: 48px;
    color: var(--primary);
}

.endpoint span {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-600);
}

.line-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.line-text {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    background: var(--white);
    padding: 2px 8px;
    border-radius: 4px;
    white-space: nowrap;
}

.line-animated {
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    position: relative;
    border-radius: 2px;
    overflow: hidden;
}

.line-animated::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.6), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { left: -100%; }
    100% { left: 100%; }
}

.features {
    padding: 100px 0;
    background: var(--white);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    color: var(--dark);
    margin-bottom: 60px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
}

.feature-card {
    text-align: center;
    padding: 40px 24px;
    background: var(--gray-50);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    background: var(--white);
}

.feature-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient);
    border-radius: 16px;
}

.feature-icon svg {
    width: 32px;
    height: 32px;
    color: var(--white);
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--dark);
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 0.95rem;
    color: var(--gray-500);
    line-height: 1.7;
}

.download {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--gray-50) 0%, var(--white) 100%);
}

.section-desc {
    text-align: center;
    font-size: 1.125rem;
    color: var(--gray-500);
    margin-top: -40px;
    margin-bottom: 60px;
}

.download-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.download-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 48px 40px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    border: 2px solid transparent;
}

.download-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.download-card.featured {
    border-color: var(--primary);
}

.featured-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient);
    color: var(--white);
    font-size: 0.875rem;
    font-weight: 600;
    padding: 6px 20px;
    border-radius: 20px;
}

.download-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-50);
    border-radius: 20px;
}

.download-icon svg {
    width: 40px;
    height: 40px;
    color: var(--primary);
}

.download-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 12px;
}

.download-desc {
    font-size: 0.95rem;
    color: var(--gray-500);
    margin-bottom: 24px;
    line-height: 1.7;
}

.download-platform {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    margin-bottom: 32px;
}

.platform-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.875rem;
    padding: 8px 16px;
    border-radius: 20px;
}

.platform-badge.available {
    background: #dcfce7;
    color: #166534;
}

.platform-badge.coming {
    background: var(--gray-100);
    color: var(--gray-500);
}

.btn-download {
    width: 100%;
    padding: 16px 24px;
}

.about {
    padding: 100px 0;
    background: var(--white);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    font-size: 1.125rem;
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 48px;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.95rem;
    color: var(--gray-500);
}

.footer {
    background: var(--dark);
    color: var(--gray-300);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-brand .nav-brand {
    margin-bottom: 16px;
}

.footer-brand .brand-text {
    color: var(--white);
    -webkit-text-fill-color: var(--white);
}

.footer-brand p {
    font-size: 0.95rem;
}

.footer-links {
    display: flex;
    gap: 60px;
}

.footer-column h4 {
    color: var(--white);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.footer-column ul {
    list-style: none;
}

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

.footer-column a {
    color: var(--gray-400);
    text-decoration: none;
    font-size: 0.95rem;
    transition: var(--transition);
}

.footer-column a:hover {
    color: var(--white);
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid var(--gray-800);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.875rem;
    color: var(--gray-500);
}

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .navbar .container {
        height: 64px;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        border-bottom: 1px solid var(--gray-100);
        box-shadow: var(--shadow);
    }

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

    .mobile-menu-btn {
        display: flex;
    }

    .wechat-popup {
        position: static;
        opacity: 0;
        visibility: hidden;
        transform: none !important;
        box-shadow: none;
        border: 1px solid var(--gray-200);
        margin-top: 8px;
        max-width: 200px;
    }

    .wechat-popup::before {
        display: none;
    }

    .wechat-popup.show {
        opacity: 1;
        visibility: visible;
    }

    .wechat-popup img {
        width: 160px;
    }

    .nav-about-wrapper {
        display: inline-block;
    }

    .hero {
        padding: 120px 0 60px;
    }

    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

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

    .hero-desc {
        font-size: 1rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .visual-card {
        max-width: 100%;
    }

    .endpoint svg {
        width: 36px;
        height: 36px;
    }

    .features {
        padding: 60px 0;
    }

    .section-title {
        font-size: 2rem;
        margin-bottom: 40px;
    }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .feature-card {
        padding: 32px 20px;
    }

    .download {
        padding: 60px 0;
    }

    .section-desc {
        margin-top: -24px;
        margin-bottom: 40px;
    }

    .download-cards {
        grid-template-columns: 1fr;
    }

    .download-card {
        padding: 40px 24px;
    }

    .about {
        padding: 60px 0;
    }

    .about-content p {
        font-size: 1rem;
    }

    .about-stats {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .stat-number {
        font-size: 2rem;
    }

    .footer {
        padding: 40px 0 20px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .footer-links {
        gap: 40px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

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

    .visual-content {
        padding: 30px 20px;
    }

    .download-platform {
        flex-direction: column;
    }
}