/* ===== CSS Variables ===== */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --primary-50: #eff6ff;
    --secondary: #0ea5e9;
    --accent: #f59e0b;
    --accent-light: #fef3c7;
    --text: #0f172a;
    --text-secondary: #475569;
    --text-light: #94a3b8;
    --bg: #ffffff;
    --bg-light: #f8fafc;
    --bg-gray: #f1f5f9;
    --border: #e2e8f0;
    --radius: 12px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --max-w: 1200px;
    --transition: 0.25s ease;
}

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

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

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

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

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

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

ul,
ol {
    list-style: none;
}

.container {
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Header ===== */
.site-header {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 0 24px;
}

.logo {
    font-size: 24px;
    font-weight: 800;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 10px;
    letter-spacing: -0.5px;
}

.logo svg {
    width: 32px;
    height: 32px;
}

.logo span {
    color: var(--text);
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 15px;
    font-weight: 500;
    position: relative;
    transition: color var(--transition);
}

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

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 0;
    right: 0;
    height: 2.5px;
    background: var(--primary);
    border-radius: 2px;
}

.nav-cta {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff !important;
    padding: 10px 24px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
    transition: all var(--transition);
}

.nav-cta:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(37, 99, 235, 0.4);
    color: #fff !important;
}

.mobile-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--text);
}

/* ===== Hero ===== */
.hero {
    padding: 80px 0 60px;
    background: linear-gradient(165deg, #eff6ff 0%, #dbeafe 40%, #e0f2fe 70%, #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, 0.08) 0%, transparent 70%);
    border-radius: 50%;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(14, 165, 233, 0.06) 0%, transparent 70%);
    border-radius: 50%;
}

.hero .container {
    position: relative;
    z-index: 1;
}

.hero h1 {
    font-size: 48px;
    font-weight: 900;
    line-height: 1.2;
    margin-bottom: 20px;
    color: var(--text);
    letter-spacing: -1px;
}

.hero h1 em {
    font-style: normal;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero .subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    max-width: 600px;
    margin-bottom: 12px;
    font-weight: 400;
}

.hero .tagline {
    font-size: 16px;
    color: var(--text-light);
    margin-bottom: 32px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all var(--transition);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
    color: #fff;
}

.btn-outline {
    background: #fff;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary-50);
    border-color: var(--primary-dark);
}

/* Stats Bar */
.stats-bar {
    display: flex;
    gap: 0;
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    max-width: 800px;
}

.stat-item {
    flex: 1;
    text-align: center;
    padding: 24px 16px;
    border-right: 1px solid var(--border);
    transition: background var(--transition);
}

.stat-item:last-child {
    border-right: none;
}

.stat-item:hover {
    background: var(--primary-50);
}

.stat-num {
    font-size: 28px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.2;
}

.stat-label {
    font-size: 13px;
    color: var(--text-light);
    margin-top: 4px;
}

/* ===== Section ===== */
.section {
    padding: 80px 0;
}

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

.section-title {
    font-size: 32px;
    font-weight: 800;
    text-align: center;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.section-title em {
    font-style: normal;
    color: var(--primary);
}

.section-desc {
    text-align: center;
    color: var(--text-secondary);
    font-size: 17px;
    max-width: 640px;
    margin: 0 auto 48px;
    line-height: 1.7;
}

/* ===== Feature Cards ===== */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.feature-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    opacity: 0;
    transition: opacity var(--transition);
}

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

.feature-card:hover::before {
    opacity: 1;
}

.feature-icon {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    background: linear-gradient(135deg, var(--primary-light), #e0f2fe);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
}

.feature-icon svg {
    width: 26px;
    height: 26px;
    color: var(--primary);
}

.feature-card h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text);
}

.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 14px;
}

.feature-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
}

.feature-link:hover {
    gap: 8px;
    color: var(--primary-dark);
}

.feature-link svg {
    width: 16px;
    height: 16px;
    transition: transform var(--transition);
}

.feature-card:hover .feature-link svg {
    transform: translateX(2px);
}

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

.solution-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    transition: all var(--transition);
    display: flex;
    flex-direction: column;
}

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

.solution-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 28px;
}

.solution-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 10px;
}

.solution-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 16px;
    flex: 1;
}

.solution-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 15px;
    font-weight: 600;
    color: var(--primary);
}

.solution-link:hover {
    gap: 10px;
    color: var(--primary-dark);
}

/* ===== Why Section ===== */
.why-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.why-item {
    text-align: center;
    padding: 24px;
}

.why-icon {
    width: 72px;
    height: 72px;
    border-radius: 20px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    background: linear-gradient(135deg, var(--primary-50), #e0f2fe);
}

.why-item h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 10px;
}

.why-item p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== CTA Section ===== */
.cta-section {
    padding: 80px 0;
    background: linear-gradient(135deg, #1e3a8a 0%, #1d4ed8 40%, #2563eb 100%);
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -40%;
    right: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(14, 165, 233, 0.2) 0%, transparent 70%);
    border-radius: 50%;
}

.cta-section .container {
    position: relative;
    z-index: 1;
    text-align: center;
}

.cta-section h2 {
    font-size: 36px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 16px;
}

.cta-section p {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 32px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.cta-section .btn {
    background: #fff;
    color: var(--primary);
    padding: 16px 40px;
    font-size: 18px;
    border-radius: 12px;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.2);
}

.cta-section .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

/* ===== Footer ===== */
.site-footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 60px 0 28px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h4 {
    color: #fff;
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer-col p {
    font-size: 14px;
    line-height: 1.8;
}

.footer-col a {
    display: block;
    color: #94a3b8;
    font-size: 14px;
    padding: 5px 0;
    transition: color var(--transition);
}

.footer-col a:hover {
    color: #fff;
    padding-left: 4px;
}

.footer-bottom {
    border-top: 1px solid #1e293b;
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
    color: #64748b;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .solution-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 24px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
        gap: 16px;
    }

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

    .mobile-toggle {
        display: block;
    }

    .hero {
        padding: 48px 0 40px;
    }

    .hero h1 {
        font-size: 32px;
    }

    .hero .subtitle {
        font-size: 17px;
    }

    .stats-bar {
        flex-wrap: wrap;
    }

    .stat-item {
        flex: 1 1 50%;
        border-bottom: 1px solid var(--border);
    }

    .section-title {
        font-size: 26px;
    }

    .feature-grid,
    .solution-grid,
    .why-grid {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .cta-section h2 {
        font-size: 28px;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 26px;
    }

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

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

    .stats-bar {
        flex-direction: column;
    }

    .stat-item {
        border-right: none;
        border-bottom: 1px solid var(--border);
    }

    .footer-grid {
        grid-template-columns: 1fr;
    }
}

/* Feature Detail Overrides */
.feature-hero {
    padding: 60px 0 50px;
    background: linear-gradient(165deg, #eff6ff 0%, #dbeafe 40%, #e0f2fe 70%, #f0f9ff 100%);
    position: relative;
    overflow: hidden;
}

.feature-hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.08) 0%, transparent 70%);
    border-radius: 50%;
}

.feature-hero .container {
    position: relative;
    z-index: 1;
}

.feature-hero h1 {
    font-size: 40px;
    font-weight: 900;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.feature-hero h1 em {
    font-style: normal;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-hero p {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 650px;
    margin-bottom: 24px;
}

.breadcrumb {
    padding: 16px 0;
    font-size: 14px;
    color: var(--text-light);
}

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

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

.breadcrumb span {
    margin: 0 8px;
}

.faq-list {
    max-width: 760px;
    margin: 0 auto;
}

.faq-item {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 12px;
    overflow: hidden;
    transition: box-shadow var(--transition);
}

.faq-item:hover {
    box-shadow: var(--shadow-md);
}

.faq-q {
    padding: 18px 24px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--bg-light);
    font-size: 16px;
}

.faq-q::after {
    content: '+';
    font-size: 22px;
    color: var(--primary);
    transition: transform var(--transition);
    font-weight: 300;
}

.faq-item.open .faq-q::after {
    transform: rotate(45deg);
}

.faq-a {
    padding: 0 24px;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease;
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
}

.faq-item.open .faq-a {
    padding: 18px 24px;
    max-height: 300px;
}

.cta-banner {
    background: linear-gradient(135deg, #1e3a8a 0%, #1d4ed8 40%, #2563eb 100%);
    color: #fff;
    text-align: center;
    padding: 56px 32px;
    border-radius: var(--radius-lg);
    margin: 40px 0;
    position: relative;
    overflow: hidden;
}

.cta-banner::before {
    content: '';
    position: absolute;
    top: -40%;
    right: -10%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(14, 165, 233, 0.2) 0%, transparent 70%);
    border-radius: 50%;
}

.cta-banner h2 {
    font-size: 28px;
    font-weight: 800;
    margin-bottom: 12px;
    position: relative;
    z-index: 1;
}

.cta-banner p {
    opacity: 0.9;
    margin-bottom: 24px;
    font-size: 17px;
    position: relative;
    z-index: 1;
}

.cta-banner .btn {
    background: #fff;
    color: var(--primary);
    position: relative;
    z-index: 1;
}

.cta-banner .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}