:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #a5b4fc;
    --accent: #f59e0b;
    --bg: #ffffff;
    --bg-soft: #f8fafc;
    --bg-dark: #0f172a;
    --text: #1e293b;
    --text-soft: #64748b;
    --text-light: #94a3b8;
    --border: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 20px 40px rgba(99,102,241,0.15);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--text);
    line-height: 1.6;
    background: var(--bg);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
img { max-width: 100%; display: block; }

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

/* Navbar */
.navbar {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}
.navbar.scrolled {
    border-bottom-color: var(--border);
    box-shadow: var(--shadow-sm);
}
.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 18px;
}
.logo-mark {
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    color: #fff;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 14px;
    letter-spacing: 1px;
}
.logo-text { color: var(--text); }

.nav-links { display: flex; gap: 28px; }
.nav-links a {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-soft);
    transition: var(--transition);
    position: relative;
}
.nav-links a:hover { color: var(--primary); }
.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::after { width: 100%; }
.nav-links a.active { color: var(--primary); }
.nav-links a.active::after { width: 100%; }

.lang-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-soft);
    padding: 6px 12px;
    border: 1px solid var(--border);
    border-radius: 999px;
    transition: var(--transition);
}
.lang-toggle:hover { border-color: var(--primary); color: var(--primary); }
.lang-btn { transition: var(--transition); }
.lang-btn.active { color: var(--primary); }
.lang-divider { color: var(--border); }

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}
.menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text);
    transition: var(--transition);
}

/* Hero */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 24px 80px;
    overflow: hidden;
}
.hero-bg { position: absolute; inset: 0; z-index: -1; overflow: hidden; }
.grid-bg {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(to right, rgba(99,102,241,0.06) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(99,102,241,0.06) 1px, transparent 1px);
    background-size: 60px 60px;
}
.blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
    animation: float 12s ease-in-out infinite;
}
.blob-1 {
    width: 500px; height: 500px;
    background: var(--primary);
    top: -100px; right: -100px;
}
.blob-2 {
    width: 400px; height: 400px;
    background: var(--accent);
    bottom: -100px; left: -100px;
    animation-delay: -6s;
}
@keyframes float {
    0%, 100% { transform: translate(0,0) scale(1); }
    50% { transform: translate(40px,-40px) scale(1.1); }
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
    animation: fadeInUp 1s ease-out;
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.hero-badge {
    display: inline-block;
    padding: 8px 20px;
    background: rgba(99,102,241,0.1);
    border: 1px solid rgba(99,102,241,0.2);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 28px;
}

.hero-title {
    font-size: clamp(40px, 7vw, 72px);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin-bottom: 24px;
}
.gradient-text {
    background: linear-gradient(135deg, var(--primary), #8b5cf6, #ec4899);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

.hero-subtitle {
    font-size: clamp(16px, 2vw, 19px);
    color: var(--text-soft);
    max-width: 720px;
    margin: 0 auto 40px;
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 64px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: 999px;
    font-size: 15px;
    font-weight: 600;
    transition: var(--transition);
    white-space: nowrap;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    color: #fff;
    box-shadow: 0 8px 24px rgba(99,102,241,0.3);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(99,102,241,0.4);
}
.btn-secondary {
    background: #fff;
    color: var(--text);
    border: 2px solid var(--border);
}
.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-2px);
}
.btn-full { width: 100%; }

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 48px;
    flex-wrap: wrap;
}
.stat { text-align: center; }
.stat-num {
    font-size: 44px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1;
}
.stat-num span { font-size: 28px; }
.stat-label {
    font-size: 14px;
    color: var(--text-soft);
    margin-top: 8px;
    font-weight: 500;
}

/* Section Common */
section { padding: 100px 0; }
.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 64px;
}
.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(99,102,241,0.08);
    border: 1px solid rgba(99,102,241,0.2);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 16px;
}
.section-title {
    font-size: clamp(32px, 4.5vw, 48px);
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
}
.section-desc {
    font-size: 17px;
    color: var(--text-soft);
    line-height: 1.8;
}

/* Page Hero (sub-pages) */
.page-hero {
    background: linear-gradient(135deg, #eef2ff 0%, #fdf4ff 100%);
    position: relative;
    padding: 140px 24px 80px;
    overflow: hidden;
}
.page-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(to right, rgba(99,102,241,0.06) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(99,102,241,0.06) 1px, transparent 1px);
    background-size: 60px 60px;
    z-index: 0;
}
.page-hero .container { position: relative; z-index: 1; }

/* Services */
.services { background: var(--bg-soft); }
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}
.service-card {
    background: #fff;
    padding: 40px 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.service-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), #8b5cf6);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}
.service-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.service-card:hover::before { transform: scaleX(1); }
.service-icon {
    font-size: 44px;
    margin-bottom: 20px;
    display: inline-block;
    width: 72px; height: 72px;
    line-height: 72px;
    text-align: center;
    background: linear-gradient(135deg, rgba(99,102,241,0.1), rgba(139,92,246,0.1));
    border-radius: 16px;
}
.service-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}
.service-card p {
    color: var(--text-soft);
    font-size: 15px;
    line-height: 1.75;
}

/* About */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}
.about-text .section-header {
    text-align: left;
    margin: 0 0 24px;
}
.about-text p {
    color: var(--text-soft);
    margin-bottom: 20px;
    line-height: 1.85;
    font-size: 16px;
}
.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-top: 32px;
}
.feature-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 500;
    font-size: 15px;
}
.feature-icon {
    width: 24px; height: 24px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    color: #fff;
    border-radius: 50%;
    font-size: 12px;
    flex-shrink: 0;
}
.about-visual { display: flex; justify-content: center; }
.code-window {
    background: #0f172a;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 30px 60px rgba(15,23,42,0.3);
    width: 100%;
    max-width: 500px;
}
.code-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 20px;
    background: #1e293b;
    border-bottom: 1px solid #334155;
}
.dot { width: 12px; height: 12px; border-radius: 50%; }
.dot-red { background: #ef4444; }
.dot-yellow { background: #f59e0b; }
.dot-green { background: #10b981; }
.code-title {
    margin-left: 12px;
    color: #94a3b8;
    font-size: 13px;
    font-family: 'Courier New', monospace;
}
.code-body { padding: 28px; overflow-x: auto; }
.code-body pre {
    font-family: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
    font-size: 13px;
    line-height: 1.75;
    color: #e2e8f0;
}
.code-kw { color: #c084fc; }
.code-var { color: #60a5fa; }
.code-prop { color: #f472b6; }
.code-str { color: #34d399; }
.code-num { color: #fbbf24; }

/* Projects */
.projects { background: var(--bg-soft); }
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 28px;
}
.project-card {
    background: #fff;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
    transition: var(--transition);
}
.project-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.project-image {
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}
.project-image::after {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center, transparent 30%, rgba(0,0,0,0.1));
}
.project-icon {
    font-size: 72px;
    z-index: 1;
    filter: drop-shadow(0 4px 12px rgba(0,0,0,0.2));
}
.project-content { padding: 28px; }
.project-tag {
    display: inline-block;
    padding: 4px 12px;
    background: rgba(99,102,241,0.08);
    color: var(--primary);
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 12px;
}
.project-content h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}
.project-content p {
    color: var(--text-soft);
    font-size: 14px;
    line-height: 1.75;
    margin-bottom: 20px;
}
.project-tech { display: flex; flex-wrap: wrap; gap: 8px; }
.project-tech span {
    padding: 4px 12px;
    background: var(--bg-soft);
    color: var(--text-soft);
    border-radius: 6px;
    font-size: 12px;
    font-weight: 500;
}

/* Team */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 28px;
}
.team-card {
    text-align: center;
    padding: 40px 28px;
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--border);
    transition: var(--transition);
}
.team-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.team-avatar {
    width: 100px; height: 100px;
    margin: 0 auto 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 36px;
    font-weight: 700;
    color: #fff;
}
.team-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.team-role {
    display: block;
    color: var(--primary);
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 16px;
}
.team-card p { color: var(--text-soft); font-size: 14px; line-height: 1.7; }

/* Process */
.process {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: #fff;
}
.process .section-tag {
    background: rgba(99,102,241,0.2);
    border-color: rgba(99,102,241,0.4);
    color: var(--primary-light);
}
.process .section-title { color: #fff; }
.process-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 24px;
}
.step {
    padding: 32px 24px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius-lg);
    transition: var(--transition);
    position: relative;
}
.step:hover {
    background: rgba(255,255,255,0.06);
    transform: translateY(-4px);
    border-color: rgba(99,102,241,0.4);
}
.step-num {
    font-size: 48px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1;
    margin-bottom: 16px;
    font-family: 'Inter', monospace;
}
.step h4 { font-size: 18px; margin-bottom: 8px; }
.step p { color: #94a3b8; font-size: 14px; line-height: 1.7; }

/* Contact */
.contact { background: var(--bg-soft); }
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: start;
}
.contact-info .section-header {
    text-align: left;
    margin: 0 0 24px;
}
.contact-info > p {
    color: var(--text-soft);
    margin-bottom: 32px;
    line-height: 1.85;
    font-size: 16px;
}
.contact-items { display: flex; flex-direction: column; gap: 20px; }
.contact-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    padding: 20px;
    background: #fff;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    transition: var(--transition);
}
.contact-item:hover {
    border-color: var(--primary);
    transform: translateX(4px);
}
.contact-icon {
    font-size: 24px;
    width: 48px; height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(99,102,241,0.1), rgba(139,92,246,0.1));
    border-radius: 12px;
    flex-shrink: 0;
}
.contact-label {
    font-size: 13px;
    color: var(--text-soft);
    margin-bottom: 4px;
    font-weight: 500;
}
.contact-value {
    font-size: 15px;
    font-weight: 600;
    color: var(--text);
}

.contact-form {
    background: #fff;
    padding: 40px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-md);
}
.form-group { margin-bottom: 20px; }
.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text);
}
.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1.5px solid var(--border);
    border-radius: 10px;
    font-size: 15px;
    font-family: inherit;
    transition: var(--transition);
    background: var(--bg-soft);
    color: var(--text);
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    background: #fff;
    box-shadow: 0 0 0 4px rgba(99,102,241,0.1);
}
.form-group textarea { resize: vertical; min-height: 120px; }

/* CTA Section */
.cta-section { padding: 80px 0; background: var(--bg-soft); }
.cta-box {
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    border-radius: var(--radius-lg);
    padding: 48px 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
    flex-wrap: wrap;
    box-shadow: 0 20px 60px rgba(99,102,241,0.3);
}
.cta-text h2 {
    color: #fff;
    font-size: clamp(24px, 3vw, 32px);
    font-weight: 800;
    margin-bottom: 8px;
}
.cta-text p { color: rgba(255,255,255,0.85); font-size: 15px; }
.cta-box .btn-primary {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 8px 24px rgba(0,0,0,0.15);
    white-space: nowrap;
}
.cta-box .btn-primary:hover {
    background: #fff;
    color: var(--primary-dark);
    transform: translateY(-2px);
}

@media (max-width: 768px) {
    .cta-box { padding: 32px; flex-direction: column; text-align: center; }
}

/* Footer */
.footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 64px 0 24px;
}
.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 48px;
}
.footer-col .logo { color: #fff; margin-bottom: 16px; display: inline-flex; }
.footer-col .logo-text { color: #fff; }
.footer-col p { font-size: 14px; line-height: 1.75; margin-top: 16px; }
.footer-col h4 {
    color: #fff;
    font-size: 15px;
    margin-bottom: 20px;
    font-weight: 700;
}
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul a { font-size: 14px; transition: var(--transition); }
.footer-col ul a:hover { color: var(--primary-light); }

.social-links { display: flex; gap: 12px; }
.social-link {
    width: 40px; height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 10px;
    color: #e2e8f0;
    font-weight: 600;
    transition: var(--transition);
    position: relative;
}
.social-link:hover {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
    transform: translateY(-2px);
}
.qr-code-col {
    display: flex;
    flex-direction: column;
    align-items: center;
}
.qr-code-box {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 16px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.1);
}
.qr-code {
    width: 120px;
    height: 120px;
    border-radius: 8px;
    margin-bottom: 8px;
}
.qr-label {
    font-size: 13px;
    color: #64748b;
    margin: 0;
}

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.08);
    text-align: center;
    font-size: 13px;
}

.footer-bottom .beian {
    margin-top: 8px;
    font-size: 12px;
}

.footer-bottom .beian a {
    color: rgba(255, 255, 255, 0.55);
    text-decoration: none;
    transition: color 0.25s ease;
}

.footer-bottom .beian a:hover {
    color: var(--primary);
}

/* Back to Top */
.back-to-top {
    position: fixed;
    bottom: 32px; right: 32px;
    width: 48px; height: 48px;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    color: #fff;
    border-radius: 50%;
    font-size: 20px;
    font-weight: 700;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    pointer-events: none;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 999;
}
.back-to-top.visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}
.back-to-top:hover { transform: translateY(-4px); }

/* Responsive */
@media (max-width: 960px) {
    .about-grid, .contact-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .nav-links, .lang-toggle { display: none; }
    .menu-toggle { display: flex; }
    .nav-links.active {
        display: flex;
        position: absolute;
        top: 100%; left: 0; right: 0;
        flex-direction: column;
        background: #fff;
        padding: 24px;
        gap: 20px;
        box-shadow: var(--shadow-md);
        border-top: 1px solid var(--border);
    }
    section { padding: 64px 0; }
    .hero { padding: 100px 24px 64px; min-height: auto; }
    .hero-stats { gap: 32px; }
    .stat-num { font-size: 36px; }
    .about-features { grid-template-columns: 1fr; }
    .contact-form { padding: 28px; }
    .process-steps { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
    .footer-grid { grid-template-columns: 1fr; }
    .hero-actions .btn { width: 100%; }
}

/* Product cards */
.product-card {
    text-align: left;
    cursor: pointer;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    background: #fff;
    padding: 28px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.product-card::after {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), #8b5cf6);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}
.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.product-card:hover::after { transform: scaleX(1); }
.product-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 12px; color: var(--text); }
.product-card p { color: var(--text-soft); font-size: 14px; line-height: 1.7; margin-bottom: 16px; }
.product-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    color: var(--primary);
    font-weight: 600;
    font-size: 14px;
}
.product-card:hover .product-link { transform: translateX(4px); }

/* Back link */
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--primary);
    font-weight: 600;
    font-size: 14px;
    margin-bottom: 20px;
    padding: 8px 16px;
    background: rgba(99,102,241,0.08);
    border-radius: 999px;
    transition: var(--transition);
}
.back-link:hover {
    background: rgba(99,102,241,0.15);
    transform: translateX(-3px);
}

/* Page marker (hidden, used by JS) */
#page-marker { display: none; }

/* Reveal animation */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* Download Section */
.download-section { padding: 80px 0; }
.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}
.download-grid-single {
    display: flex;
    justify-content: center;
}
.download-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px;
    text-align: center;
    transition: var(--transition);
    max-width: 400px;
    width: 100%;
}
.download-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.download-card.android {
    border-color: #22c55e;
    background: linear-gradient(135deg, #f0fdf4 0%, #ffffff 100%);
}
.download-icon {
    font-size: 56px;
    margin-bottom: 16px;
}
.download-card h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text);
}
.download-card p {
    color: var(--text-soft);
    font-size: 15px;
    margin-bottom: 24px;
}
.download-info {
    display: flex;
    justify-content: center;
    gap: 16px;
    font-size: 14px;
    color: var(--text-soft);
    margin-bottom: 20px;
}
.download-info span { margin-right: 4px; }

/* Version Tabs */
.version-tabs {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 24px;
    padding: 8px;
    background: rgba(0,0,0,0.04);
    border-radius: 10px;
}
.version-tab {
    padding: 10px 24px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-soft);
    transition: var(--transition);
    background: transparent;
}
.version-tab.active {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
.version-tab:hover:not(.active) { color: var(--text); }

/* Version Content */
.version-content {
    display: none;
}
.version-content.active {
    display: block;
}

/* Download Buttons */
.download-btn {
    display: block;
    width: 100%;
    padding: 14px 24px;
    border-radius: 999px;
    font-size: 15px;
    font-weight: 600;
    transition: var(--transition);
    margin-bottom: 12px;
}
.download-btn.primary {
    background: linear-gradient(135deg, #22c55e, #16a34a);
    color: #fff;
    box-shadow: 0 4px 16px rgba(34, 197, 94, 0.3);
}
.download-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(34, 197, 94, 0.4);
}
.download-btn.secondary {
    background: rgba(0,0,0,0.05);
    color: var(--text);
    border: 1px solid var(--border);
}
.download-btn.secondary:hover {
    background: rgba(0,0,0,0.08);
    border-color: var(--text-soft);
}

/* Download Tip */
.download-tip {
    margin-top: 16px;
    padding: 12px 16px;
    background: rgba(251, 191, 36, 0.1);
    border-radius: 8px;
    font-size: 13px;
    color: #92400e;
}

/* QR Code Container */
.qrcode-container {
    margin-bottom: 20px;
}
.qrcode {
    width: 150px;
    height: 150px;
    margin: 0 auto 12px;
    background: #fff;
    padding: 12px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.qrcode img { width: 100%; height: 100%; }
.qrcode-container p {
    font-size: 13px;
    color: var(--text-soft);
    margin: 0;
}

/* System Requirements */
.system-requirements { background: var(--bg-soft); }
.requirements-table { overflow-x: auto; }
.requirements-table table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.04);
}
.requirements-table th,
.requirements-table td {
    padding: 16px 24px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}
.requirements-table th {
    background: var(--bg-soft);
    font-weight: 600;
    color: var(--text);
    font-size: 14px;
}
.requirements-table td { font-size: 14px; color: var(--text-soft); }
.requirements-table tr:last-child td { border-bottom: none; }

/* Update History */
.update-history { padding: 80px 0; }
.update-list { max-width: 800px; margin: 0 auto; }
.update-item {
    padding: 28px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 16px;
    transition: var(--transition);
}
.update-item:hover {
    border-color: var(--primary);
    box-shadow: 0 4px 16px rgba(99,102,241,0.1);
}
.update-version {
    display: inline-block;
    padding: 4px 12px;
    background: rgba(99,102,241,0.1);
    color: var(--primary);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
    margin-right: 12px;
}
.update-date {
    font-size: 13px;
    color: var(--text-soft);
}
.update-changes {
    margin-top: 16px;
    padding-left: 0;
}
.update-changes li {
    position: relative;
    padding-left: 20px;
    color: var(--text-soft);
    font-size: 14px;
    line-height: 1.8;
    margin-bottom: 8px;
}
.update-changes li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #22c55e;
    font-weight: 700;
}

/* FAQ Download */
.faq-download { background: var(--bg-soft); }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    margin-bottom: 12px;
    border: 1px solid var(--border);
}
.faq-q {
    padding: 20px 24px;
    font-weight: 600;
    color: var(--text);
    cursor: pointer;
    position: relative;
    transition: var(--transition);
}
.faq-q:hover { background: rgba(99,102,241,0.03); }
.faq-q::after {
    content: '+';
    position: absolute;
    right: 24px;
    font-size: 20px;
    font-weight: 400;
    transition: var(--transition);
}
.faq-q.active::after { transform: rotate(45deg); }
.faq-a {
    padding: 0 24px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    color: var(--text-soft);
    font-size: 14px;
    line-height: 1.8;
}
.faq-a.active {
    padding-bottom: 20px;
    max-height: 200px;
}