/* Yinanna - Dark Theme CSS */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #1a1a25;
    --bg-hover: #252535;
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    --border-color: #27273a;
    --success: #22c55e;
    --warning: #f59e0b;
    --error: #ef4444;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.6);
    --radius: 12px;
    --radius-sm: 6px;
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Language Display Control - Strict Mutual Exclusion */
.lang-en, .lang-zh {
    display: none !important;
}

/* English Mode: Show EN, Hide ZH */
html[lang="en"] .lang-en,
body.lang-en .lang-en {
    display: block !important;
}

html[lang="en"] .lang-zh,
body.lang-en .lang-zh {
    display: none !important;
}

/* Chinese Mode: Show ZH, Hide EN */
html[lang="zh"] .lang-zh,
body.lang-zh .lang-zh {
    display: block !important;
}

html[lang="zh"] .lang-en,
body.lang-zh .lang-en {
    display: none !important;
}

/* Inline elements */
html[lang="en"] span.lang-en,
html[lang="en"] a.lang-en,
html[lang="en"] button.lang-en,
body.lang-en span.lang-en,
body.lang-en a.lang-en,
body.lang-en button.lang-en {
    display: inline !important;
}

html[lang="zh"] span.lang-zh,
html[lang="zh"] a.lang-zh,
html[lang="zh"] button.lang-zh,
body.lang-zh span.lang-zh,
body.lang-zh a.lang-zh,
body.lang-zh button.lang-zh {
    display: inline !important;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 10, 15, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    padding: 0 5%;
}

.navbar-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--text-primary);
}

.brand-icon {
    width: 40px;
    height: 40px;
    background: var(--accent-gradient);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 30px;
    list-style: none;
}

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

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-gradient);
    transition: var(--transition);
}

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

.lang-switcher {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: 20px;
    padding-left: 20px;
    border-left: 1px solid var(--border-color);
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 6px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 500;
    transition: var(--transition);
}

.lang-btn:hover {
    border-color: var(--accent-primary);
    color: var(--text-primary);
}

.lang-btn.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
}

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

.mobile-menu-btn span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 100px 5% 60px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse at 20% 20%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(139, 92, 246, 0.15) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    max-width: 900px;
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 8px 16px;
    border-radius: 50px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.hero-badge .dot {
    width: 8px;
    height: 8px;
    background: var(--success);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    background: linear-gradient(135deg, #fff 0%, #a1a1aa 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero h1 .highlight {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

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

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

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-card);
    border-color: var(--accent-primary);
}

/* Section Styles */
section {
    padding: 100px 5%;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}

.section-header h2 {
    font-size: clamp(2rem, 4vw, 2.8rem);
    font-weight: 700;
    margin-bottom: 16px;
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
    max-width: 1400px;
    margin: 0 auto;
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 32px;
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-lg);
}

.card-icon {
    width: 56px;
    height: 56px;
    background: var(--bg-hover);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--accent-primary);
}

.card h3 {
    font-size: 1.3rem;
    margin-bottom: 12px;
    font-weight: 600;
}

.card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* Services Section */
.services {
    background: var(--bg-secondary);
}

.service-card {
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--accent-gradient);
    transform: scaleX(0);
    transition: var(--transition);
}

.service-card:hover::before {
    transform: scaleX(1);
}

/* Stats Section */
.stats {
    padding: 80px 5%;
    background: var(--bg-card);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.stat-item h3 {
    font-size: 3rem;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
}

.stat-item p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* Team Section */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
}

.team-card {
    text-align: center;
    padding: 40px 24px;
}

.team-avatar {
    width: 100px;
    height: 100px;
    background: var(--bg-hover);
    border-radius: 50%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
}

.team-card h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.team-card p {
    color: var(--accent-primary);
    font-size: 0.9rem;
    margin-bottom: 12px;
}

.team-card .desc {
    color: var(--text-secondary);
    font-size: 0.85rem;
    line-height: 1.6;
}

/* Contact Section */
.contact {
    background: var(--bg-secondary);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    max-width: 1200px;
    margin: 0 auto;
}

.contact-info h3 {
    font-size: 1.5rem;
    margin-bottom: 24px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 24px;
}

.contact-icon {
    width: 48px;
    height: 48px;
    background: var(--bg-card);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-primary);
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 1rem;
    margin-bottom: 4px;
}

.contact-item p, .contact-item a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.contact-item a:hover {
    color: var(--accent-primary);
}

.contact-form {
    background: var(--bg-card);
    padding: 40px;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
}

.form-group textarea {
    min-height: 120px;
    resize: vertical;
}

/* Footer */
.footer {
    background: var(--bg-card);
    padding: 60px 5% 30px;
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    max-width: 1400px;
    margin: 0 auto 40px;
}

.footer-brand {
    max-width: 300px;
}

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

.footer-brand p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.7;
}

.footer-column h4 {
    font-size: 1rem;
    margin-bottom: 20px;
    font-weight: 600;
}

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

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

.footer-column a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

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

.footer-bottom {
    max-width: 1400px;
    margin: 0 auto;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 0.85rem;
}

.footer-bottom-links {
    display: flex;
    gap: 24px;
}

.footer-bottom-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.85rem;
    transition: var(--transition);
}

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

/* Legal Pages */
.legal-page {
    padding-top: 120px;
    min-height: 100vh;
}

.legal-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 5% 100px;
}

.legal-header {
    text-align: center;
    margin-bottom: 60px;
}

.legal-header h1 {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 16px;
}

.legal-header .last-updated {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.legal-section {
    margin-bottom: 40px;
}

.legal-section h2 {
    font-size: 1.4rem;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.legal-section h3 {
    font-size: 1.1rem;
    margin: 20px 0 12px;
    color: var(--text-secondary);
}

.legal-section p,
.legal-section li {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 12px;
}

.legal-section ul {
    padding-left: 24px;
    margin-bottom: 16px;
}

.legal-section a {
    color: var(--accent-primary);
    text-decoration: none;
}

.legal-section a:hover {
    text-decoration: underline;
}

/* About Page */
.about-hero {
    padding-top: 120px;
    min-height: auto;
}

.about-content {
    max-width: 1200px;
    margin: 0 auto;
}

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

.about-text h2 {
    font-size: 2.2rem;
    margin-bottom: 24px;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.8;
}

.about-image {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 40px;
    text-align: center;
    border: 1px solid var(--border-color);
}

.about-image .icon {
    font-size: 5rem;
    margin-bottom: 20px;
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-top: 40px;
}

.value-item {
    padding: 20px;
    background: var(--bg-card);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
}

.value-item h4 {
    font-size: 1rem;
    margin-bottom: 8px;
    color: var(--accent-primary);
}

.value-item p {
    font-size: 0.9rem;
    margin: 0;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-in {
    animation: fadeInUp 0.6s ease forwards;
}

/* Responsive */
@media (max-width: 1024px) {
    .about-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--bg-primary);
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .lang-switcher {
        margin-left: 0;
        padding-left: 0;
        border-left: none;
        margin-top: 16px;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .card-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
    
    .values-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .stat-item h3 {
        font-size: 2.5rem;
    }
}