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

:root {
    --primary: #1a56db;
    --primary-dark: #1342a8;
    --text: #1f2937;
    --text-light: #6b7280;
    --bg: #ffffff;
    --bg-alt: #f3f4f6;
    --border: #e5e7eb;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid transparent;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.navbar.scrolled {
    border-bottom-color: var(--border);
    box-shadow: 0 1px 8px rgba(0, 0, 0, 0.06);
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: 2px;
}

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

.nav-menu a {
    text-decoration: none;
    color: var(--text);
    font-size: 15px;
    font-weight: 500;
    transition: color 0.2s;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text);
    transition: 0.3s;
}

/* Hero */
.hero {
    position: relative;
    height: 100vh;
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #1a56db 100%);
    overflow: hidden;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    position: relative;
    z-index: 1;
    color: #fff;
    padding: 0 24px;
}

.hero h1 {
    font-size: 56px;
    font-weight: 800;
    letter-spacing: 6px;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 22px;
    font-weight: 400;
    opacity: 0.9;
    margin-bottom: 12px;
    letter-spacing: 4px;
}

.hero-desc {
    font-size: 16px;
    opacity: 0.7;
    line-height: 1.8;
    margin-bottom: 36px;
}

.hero-btn {
    display: inline-block;
    padding: 14px 40px;
    border: 2px solid rgba(255, 255, 255, 0.8);
    color: #fff;
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    letter-spacing: 2px;
    border-radius: 4px;
    transition: all 0.3s;
}

.hero-btn:hover {
    background: #fff;
    color: var(--primary-dark);
}

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

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

.section-title {
    font-size: 32px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 48px;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 48px;
    height: 3px;
    background: var(--primary);
    margin: 12px auto 0;
    border-radius: 2px;
}

.subsection-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 24px;
    margin-top: 40px;
    color: var(--text);
}

.subsection-title:first-of-type {
    margin-top: 0;
}

/* About */
.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 48px;
    align-items: start;
}

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

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.stat-item {
    text-align: center;
    padding: 24px;
    background: var(--bg-alt);
    border-radius: 8px;
}

.stat-number {
    display: block;
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
}

.stat-label {
    font-size: 14px;
    color: var(--text-light);
    margin-top: 4px;
}

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 40px;
}

.card {
    background: #fff;
    padding: 28px 20px;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border);
    transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.card-icon {
    font-size: 36px;
    margin-bottom: 12px;
}

.card h4 {
    font-size: 17px;
    margin-bottom: 8px;
}

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

/* Platform */
.platform-grid {
    display: flex;
    gap: 20px;
    margin-bottom: 40px;
}

.platform-item {
    flex: 1;
    text-align: center;
    padding: 28px 16px;
    background: #fff;
    border-radius: 8px;
    border: 1px solid var(--border);
}

.platform-name {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.platform-desc {
    font-size: 14px;
    color: var(--text-light);
}

/* Brand */
.brand-section {
    background: #fff;
    padding: 32px;
    border-radius: 8px;
    border: 1px solid var(--border);
}

.brand-section p {
    font-size: 16px;
    color: var(--text-light);
    line-height: 1.8;
}

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

.tech-card {
    padding: 32px 24px;
    background: var(--bg-alt);
    border-radius: 8px;
    text-align: center;
    transition: transform 0.2s;
}

.tech-card:hover {
    transform: translateY(-4px);
}

.tech-icon {
    font-size: 40px;
    margin-bottom: 16px;
}

.tech-card h4 {
    font-size: 18px;
    margin-bottom: 12px;
}

.tech-card p {
    font-size: 14px;
    color: var(--text-light);
    line-height: 1.7;
}

/* Contact */
.contact-content {
    max-width: 500px;
    margin: 0 auto;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.contact-item {
    display: flex;
    justify-content: space-between;
    padding: 16px 24px;
    background: #fff;
    border-radius: 8px;
    border: 1px solid var(--border);
    font-size: 15px;
}

.contact-label {
    font-weight: 600;
    color: var(--text);
}

/* Footer */
.footer {
    background: #0f172a;
    color: rgba(255, 255, 255, 0.6);
    text-align: center;
    padding: 24px 0;
    font-size: 14px;
}

/* Mobile */
@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 16px 24px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
    }

    .nav-menu.active {
        display: flex;
    }

    .hero h1 {
        font-size: 36px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .about-stats {
        flex-direction: row;
    }

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

    .platform-grid {
        flex-direction: column;
    }

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

    .section {
        padding: 56px 0;
    }

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