/* 
 * AnyDesk Official CN Style Replica 
 * Brand Colors: Red (#EF4444), Dark (#1F2937), White (#FFFFFF)
 */

:root {
    --ad-red: #EF4444;       /* Official Red-like */
    --ad-red-hover: #DC2626;
    --ad-dark: #1F2937;      /* Dark Grey */
    --ad-text: #374151;      /* Body Text */
    --ad-light-bg: #F9FAFB;  /* Light Grey BG */
    --ad-border: #E5E7EB;
    --font-main: "Segoe UI", "Roboto", "Helvetica Neue", Arial, sans-serif;
}

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

body {
    font-family: var(--font-main);
    color: var(--ad-text);
    line-height: 1.5;
    background-color: #fff;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }

/* Utility Classes */
.container {
    max-width: 1200px; margin: 0 auto; padding: 0 24px;
}
.btn {
    display: inline-block; padding: 12px 32px;
    font-weight: 600; font-size: 16px; border-radius: 4px;
    cursor: pointer; transition: all 0.2s; text-align: center;
}
.btn-primary {
    background-color: var(--ad-red); color: white;
    border: 1px solid var(--ad-red);
}
.btn-primary:hover {
    background-color: var(--ad-red-hover);
    border-color: var(--ad-red-hover);
}
.btn-outline {
    background-color: transparent; color: var(--ad-dark);
    border: 1px solid var(--ad-dark);
}
.btn-outline:hover {
    background-color: var(--ad-dark); color: white;
}
.text-center { text-align: center; }
.mb-20 { margin-bottom: 20px; }
.mb-40 { margin-bottom: 40px; }

/* Navbar */
.navbar {
    height: 80px; background: white;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    position: sticky; top: 0; z-index: 1000;
}
.navbar .container {
    height: 100%; display: flex; align-items: center; justify-content: space-between;
}
.nav-logo {
    display: flex; align-items: center; gap: 8px;
    font-size: 24px; font-weight: 800; color: var(--ad-dark);
}
.nav-logo i { color: var(--ad-red); font-size: 28px; }

.nav-menu { display: flex; gap: 32px; align-items: center; }
.nav-link { font-weight: 500; color: var(--ad-text); font-size: 15px; }
.nav-link:hover { color: var(--ad-red); }

/* Hero Section */
.hero {
    padding: 100px 0; background-color: var(--ad-light-bg);
    display: flex; align-items: center; min-height: 600px;
}
.hero-content {
    display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
}
.hero-text h1 {
    font-size: 56px; line-height: 1.1; color: var(--ad-dark); margin-bottom: 24px;
    font-weight: 800;
}
.hero-text p {
    font-size: 20px; color: #6B7280; margin-bottom: 40px;
    max-width: 500px;
}
.hero-btns { display: flex; gap: 16px; }
.hero-image {
    position: relative;
}
.hero-image img {
    width: 100%; border-radius: 8px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
}

/* Trust Bar */
.trust-bar {
    padding: 40px 0; border-bottom: 1px solid var(--ad-border);
    text-align: center;
}
.trust-logos {
    display: flex; justify-content: center; gap: 60px;
    font-size: 32px; color: #9CA3AF; margin-top: 20px;
}

/* Features Section */
.section { padding: 100px 0; }
.section-header { text-align: center; max-width: 800px; margin: 0 auto 80px; }
.section-header h2 {
    font-size: 36px; color: var(--ad-dark); margin-bottom: 16px;
}
.section-header p { font-size: 18px; color: #6B7280; }

.features-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px;
}
.feature-item {
    padding: 32px; background: white;
    border-radius: 8px; border: 1px solid var(--ad-border);
    transition: transform 0.3s, box-shadow 0.3s;
}
.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}
.feature-icon {
    width: 48px; height: 48px; background: #FEF2F2;
    color: var(--ad-red); border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    font-size: 24px; margin-bottom: 24px;
}
.feature-item h3 { font-size: 20px; margin-bottom: 12px; color: var(--ad-dark); }
.feature-item p { color: #6B7280; font-size: 15px; }

/* New: Download Matrix */
.dl-matrix-grid {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
    margin-top: 40px;
}
.dl-matrix-card {
    background: #fff; padding: 24px; border-radius: 8px;
    border: 1px solid var(--ad-border); text-align: center;
    transition: all 0.2s;
}
.dl-matrix-card:hover {
    border-color: var(--ad-red); box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.dl-matrix-icon { font-size: 40px; color: var(--ad-dark); margin-bottom: 16px; }
.dl-matrix-card:hover .dl-matrix-icon { color: var(--ad-red); }
.dl-matrix-btn {
    display: inline-block; margin-top: 16px; font-size: 14px;
    color: var(--ad-red); font-weight: 600;
}

/* New: Version Comparison */
.version-comp-grid {
    display: grid; grid-template-columns: 1fr 1fr; gap: 40px;
    max-width: 900px; margin: 0 auto;
}
.version-card {
    background: #fff; padding: 40px; border-radius: 8px;
    border: 1px solid var(--ad-border);
    display: flex; flex-direction: column; align-items: center; text-align: center;
}
.version-card.highlight {
    border: 2px solid var(--ad-red); position: relative;
    box-shadow: 0 10px 30px rgba(239, 68, 68, 0.1);
}
.version-badge {
    position: absolute; top: -12px; background: var(--ad-red);
    color: white; padding: 4px 16px; border-radius: 20px;
    font-size: 12px; font-weight: 700;
}
.version-title { font-size: 24px; font-weight: 700; margin-bottom: 16px; color: var(--ad-dark); }
.version-list { margin: 24px 0; text-align: left; width: 100%; }
.version-list li { margin-bottom: 12px; color: #4B5563; font-size: 15px; }
.version-list i { color: var(--ad-red); margin-right: 8px; }

/* New: Steps */
.steps-container {
    display: flex; justify-content: space-between; gap: 40px;
    margin-top: 40px;
}
.step-item { flex: 1; text-align: center; position: relative; }
.step-num {
    width: 40px; height: 40px; background: var(--ad-red); color: white;
    border-radius: 50%; display: flex; align-items: center; justify-content: center;
    font-weight: 700; font-size: 18px; margin: 0 auto 20px;
}
.step-title { font-weight: 700; margin-bottom: 8px; color: var(--ad-dark); }

/* New: FAQ */
.faq-grid {
    display: grid; grid-template-columns: 1fr 1fr; gap: 30px;
    max-width: 1000px; margin: 0 auto;
}
.faq-item h4 { font-size: 18px; color: var(--ad-dark); margin-bottom: 8px; }
.faq-item p { color: #6B7280; font-size: 15px; }

/* New: Use Cases */
.use-case-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px;
}
.use-case-card {
    position: relative; overflow: hidden; border-radius: 8px;
    height: 300px; color: white; display: flex; flex-direction: column; justify-content: flex-end;
    padding: 30px; text-align: left;
}
.use-case-card::before {
    content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
    z-index: 1;
}
.use-case-bg {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    object-fit: cover; transition: transform 0.5s;
}
.use-case-card:hover .use-case-bg { transform: scale(1.1); }
.use-case-content { position: relative; z-index: 2; }
.use-case-title { font-size: 22px; font-weight: 700; margin-bottom: 8px; }

/* New: Tech Specs */
.tech-spec-table {
    width: 100%; border-collapse: collapse; margin-top: 40px;
    background: white; border-radius: 8px; overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.tech-spec-table th, .tech-spec-table td {
    padding: 20px; text-align: left; border-bottom: 1px solid var(--ad-border);
}
.tech-spec-table th { background: var(--ad-light-bg); color: var(--ad-dark); font-weight: 600; width: 30%; }
.tech-spec-table td { color: #4B5563; }
.tech-spec-table tr:last-child td { border-bottom: none; }

/* CTA Section */
.cta-section {
    background: var(--ad-red); color: white; padding: 80px 0;
    text-align: center;
}
.cta-section h2 { font-size: 40px; margin-bottom: 24px; }
.cta-section p { font-size: 20px; opacity: 0.9; margin-bottom: 40px; }
.btn-white {
    background: white; color: var(--ad-red);
}
.btn-white:hover { background: #F9FAFB; }

/* Download Page */
.dl-header {
    background: var(--ad-light-bg); padding: 80px 0; text-align: center;
}
.dl-header h1 { font-size: 48px; margin-bottom: 16px; color: var(--ad-dark); }
.dl-tabs {
    display: flex; justify-content: center; gap: 10px; margin-top: 40px;
    flex-wrap: wrap;
}
.dl-tab {
    padding: 12px 24px; border-radius: 4px; cursor: pointer;
    font-weight: 600; color: #6B7280;
    display: flex; align-items: center; gap: 8px;
}
.dl-tab.active {
    background: white; color: var(--ad-red);
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}
.dl-card {
    max-width: 800px; margin: -40px auto 0;
    background: white; padding: 60px;
    border-radius: 8px; box-shadow: 0 20px 50px rgba(0,0,0,0.1);
    position: relative; z-index: 10; text-align: center;
}

/* Footer */
.footer {
    background: #111827; color: white; padding: 80px 0 40px;
}
.footer-grid {
    display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px;
    margin-bottom: 60px;
}
.footer-col h4 {
    font-size: 16px; font-weight: 700; margin-bottom: 24px;
    color: #F3F4F6;
}
.footer-links li { margin-bottom: 12px; }
.footer-links a { color: #9CA3AF; font-size: 14px; }
.footer-links a:hover { color: white; }
.footer-bottom {
    border-top: 1px solid #374151; padding-top: 40px;
    text-align: center; color: #6B7280; font-size: 14px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero-content { grid-template-columns: 1fr; text-align: center; }
    .hero-btns { justify-content: center; }
    .features-grid { grid-template-columns: 1fr; }
    .dl-matrix-grid { grid-template-columns: 1fr 1fr; }
    .version-comp-grid { grid-template-columns: 1fr; }
    .steps-container { flex-direction: column; gap: 20px; }
    .faq-grid { grid-template-columns: 1fr; }
    .use-case-grid { grid-template-columns: 1fr; }
    .nav-menu { display: none; }
    .footer-grid { grid-template-columns: 1fr; }
}