/* MChat Official Website - Global Styles */
/* 2026 Deep Minimalism Design */

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

:root {
    --primary: #2563EB;
    --primary-light: #3B82F6;
    --primary-dark: #1D4ED8;
    --accent: #06B6D4;
    --bg-white: #FFFFFF;
    --bg-light: #F8F9FA;
    --bg-dark: #0F172A;
    --text-primary: #1A1A2E;
    --text-secondary: #6B7280;
    --text-light: #9CA3AF;
    --border: #E5E7EB;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --max-width: 1200px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    color: var(--text-primary);
    background: var(--bg-white);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 12px rgba(0,0,0,0.06);
    padding: 10px 0;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-logo svg {
    width: 36px;
    height: 36px;
}

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

.nav-menu a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
    position: relative;
    padding: 4px 0;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    border-radius: 1px;
}

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

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

.nav-cta {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 24px;
    background: var(--primary);
    color: #fff !important;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 4px 14px rgba(37,99,235,0.3);
}

.nav-cta:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(37,99,235,0.4);
}

.nav-cta::after {
    display: none !important;
}

/* Mobile menu toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 80px;
    background: linear-gradient(160deg, #EFF6FF 0%, #FFFFFF 40%, #F0F9FF 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(37,99,235,0.06) 0%, transparent 70%);
    border-radius: 50%;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(6,182,212,0.05) 0%, transparent 70%);
    border-radius: 50%;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 20px;
    background: rgba(37,99,235,0.08);
    border: 1px solid rgba(37,99,235,0.15);
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 32px;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--primary-dark) 100%);
    -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;
    line-height: 1.8;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 16px 36px;
    background: var(--primary);
    color: #fff;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.05rem;
    box-shadow: 0 6px 24px rgba(37,99,235,0.3);
    transition: var(--transition);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(37,99,235,0.4);
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 16px 36px;
    background: var(--bg-white);
    color: var(--text-primary);
    border: 1.5px solid var(--border);
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.05rem;
    transition: var(--transition);
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.hero-platforms {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
    flex-wrap: wrap;
}

.hero-platforms span {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
    color: var(--text-light);
}

.hero-platforms svg {
    width: 20px;
    height: 20px;
    opacity: 0.5;
}

/* ===== Section Common ===== */
.section {
    padding: 100px 24px;
}

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

.section-dark {
    background: var(--bg-dark);
    color: #fff;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    letter-spacing: -0.01em;
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.section-dark .section-header p {
    color: rgba(255,255,255,0.6);
}

/* ===== Feature Cards ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 36px 28px;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    background: linear-gradient(135deg, rgba(37,99,235,0.1), rgba(6,182,212,0.1));
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: var(--primary);
}

.feature-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
}

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

/* ===== Product Showcase ===== */
.showcase-wrapper {
    display: flex;
    align-items: center;
    gap: 64px;
}

.showcase-image {
    flex: 1;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
    aspect-ratio: 4/3;
    display: flex;
    align-items: center;
    justify-content: center;
}

.showcase-image svg {
    width: 60%;
    height: auto;
    opacity: 0.6;
}

.showcase-content {
    flex: 1;
}

.showcase-content h3 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.showcase-content p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.8;
}

.showcase-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.showcase-list li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.95rem;
}

.showcase-list li svg {
    width: 20px;
    height: 20px;
    color: var(--primary);
    flex-shrink: 0;
}

/* ===== Security Section ===== */
.security-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.security-card {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 36px 28px;
    transition: var(--transition);
}

.security-card:hover {
    background: rgba(255,255,255,0.08);
    transform: translateY(-2px);
}

.security-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #fff;
}

.security-card p {
    font-size: 0.95rem;
    color: rgba(255,255,255,0.6);
    line-height: 1.7;
}

.security-icon {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: rgba(37,99,235,0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
}

.security-icon svg {
    width: 24px;
    height: 24px;
    color: var(--accent);
}

/* ===== Stats ===== */
.stats-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    text-align: center;
}

.stat-item h3 {
    font-size: 2.8rem;
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 8px;
}

.stat-item p {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

/* ===== Download Section ===== */
.download-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.download-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 40px 24px;
    text-align: center;
    transition: var(--transition);
}

.download-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.download-card svg {
    width: 48px;
    height: 48px;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.download-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.download-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 12px 28px;
    background: var(--primary);
    color: #fff;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition);
}

.download-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

/* ===== FAQ Section ===== */
.faq-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.faq-item {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 28px;
}

.faq-item h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 14px;
    color: var(--text-primary);
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.faq-item h3 .faq-num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    background: var(--primary);
    color: #fff;
    border-radius: 50%;
    font-size: 0.8rem;
    font-weight: 700;
    flex-shrink: 0;
}

.faq-steps {
    list-style: none;
    padding-left: 38px;
}

.faq-steps li {
    position: relative;
    padding: 6px 0;
    font-size: 0.92rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.faq-steps li::before {
    content: '';
    position: absolute;
    left: -16px;
    top: 14px;
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

/* ===== Testimonials ===== */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.testimonial-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 28px;
}

.testimonial-card .stars {
    color: #FBBF24;
    font-size: 1rem;
    margin-bottom: 12px;
    letter-spacing: 2px;
}

.testimonial-card .quote {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
    font-style: italic;
}

.testimonial-card .author {
    display: flex;
    align-items: center;
    gap: 10px;
}

.testimonial-card .author-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
    font-size: 0.9rem;
}

.testimonial-card .author-info strong {
    display: block;
    font-size: 0.9rem;
}

.testimonial-card .author-info span {
    font-size: 0.8rem;
    color: var(--text-light);
}

/* ===== CTA Section ===== */
.cta-section {
    text-align: center;
    padding: 80px 24px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: #fff;
    border-radius: var(--radius-lg);
    margin: 0 24px;
}

.cta-section h2 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta-section p {
    font-size: 1.1rem;
    opacity: 0.85;
    margin-bottom: 32px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.cta-section .btn-primary {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 6px 24px rgba(0,0,0,0.15);
}

.cta-section .btn-primary:hover {
    background: #F8F9FA;
    transform: translateY(-2px);
}

/* ===== Footer ===== */
.footer {
    background: var(--bg-dark);
    color: rgba(255,255,255,0.7);
    padding: 64px 24px 32px;
}

.footer-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 48px;
}

.footer-brand h3 {
    font-size: 1.4rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 0.9rem;
    line-height: 1.7;
    margin-bottom: 16px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
}

.footer-social a svg {
    width: 16px;
    height: 16px;
    color: #fff;
}

.footer-col h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: #fff;
    margin-bottom: 16px;
}

.footer-col ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-col a {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
}

.footer-col a:hover {
    color: #fff;
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 0.85rem;
}

.footer-bottom a {
    color: rgba(255,255,255,0.5);
}

.footer-bottom a:hover {
    color: #fff;
}

/* ===== Page Header (for inner pages) ===== */
.page-header {
    padding: 160px 24px 80px;
    text-align: center;
    background: linear-gradient(160deg, #EFF6FF 0%, #FFFFFF 50%, #F0F9FF 100%);
}

.page-header h1 {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.page-header p {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ===== About Page ===== */
.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-content p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.9;
    margin-bottom: 24px;
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 48px;
}

.value-card {
    text-align: center;
    padding: 32px 20px;
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

.value-card h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.value-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== Breadcrumb ===== */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 32px;
}

.breadcrumb a {
    color: var(--text-secondary);
}

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

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
        gap: 32px;
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .showcase-wrapper {
        flex-direction: column;
        gap: 40px;
    }
    .testimonials-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    .nav-toggle {
        display: flex;
    }
    .hero h1 {
        font-size: 2.2rem;
    }
    .hero p {
        font-size: 1.05rem;
    }
    .section {
        padding: 64px 16px;
    }
    .section-header h2 {
        font-size: 1.8rem;
    }
    .features-grid,
    .security-grid,
    .faq-grid,
    .download-grid {
        grid-template-columns: 1fr;
    }
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
    }
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .page-header {
        padding: 130px 16px 60px;
    }
    .page-header h1 {
        font-size: 2rem;
    }
    .cta-section {
        margin: 0 16px;
        padding: 48px 20px;
    }
    .cta-section h2 {
        font-size: 1.6rem;
    }
    .values-grid {
        grid-template-columns: 1fr;
    }
    .hero-buttons {
        flex-direction: column;
    }
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}