:root {
    --primary: #3b78e7;
    --primary-dark: #2a5fc4;
    --accent: #fdcc52;
    --text: #1a1a2e;
    --text-muted: #5a6270;
    --bg: #f5f8fc;
    --white: #ffffff;
    --border: #e8edf3;
    --shadow: 0 8px 30px rgba(59, 120, 231, 0.12);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro SC", "PingFang SC", "Microsoft YaHei", sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s;
}

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

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

/* Header */
.site-header {
    background: var(--white);
    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: 64px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--primary), #5b9af0);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 18px;
}

.nav-links {
    display: flex;
    gap: 28px;
    list-style: none;
}

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

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

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

/* Hero */
.hero {
    background: linear-gradient(160deg, #e8f0fe 0%, #f5f8fc 50%, #fff 100%);
    padding: 80px 0 100px;
    text-align: center;
}

.hero-badge {
    display: inline-block;
    background: rgba(59, 120, 231, 0.1);
    color: var(--primary);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 20px;
}

.hero h1 {
    font-size: 48px;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.hero p {
    font-size: 18px;
    color: var(--text-muted);
    max-width: 560px;
    margin: 0 auto 36px;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 14px rgba(59, 120, 231, 0.35);
}

.btn-primary:hover {
    color: white;
    background: var(--primary-dark);
}

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

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

.section-title {
    text-align: center;
    margin-bottom: 48px;
}

.section-title h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 12px;
}

.section-title p {
    color: var(--text-muted);
    font-size: 16px;
}

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

.feature-card {
    background: var(--white);
    border-radius: 16px;
    padding: 32px 24px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: transform 0.2s;
}

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

.feature-icon {
    width: 52px;
    height: 52px;
    background: linear-gradient(135deg, #e8f0fe, #d4e4fc);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

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

/* App info */
.app-info {
    background: var(--white);
}

.app-info-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}

.app-mockup {
    background: linear-gradient(135deg, var(--primary), #5b9af0);
    border-radius: 24px;
    padding: 40px;
    color: white;
    text-align: center;
}

.app-mockup h3 {
    font-size: 28px;
    margin-bottom: 8px;
}

.app-mockup .version {
    opacity: 0.85;
    font-size: 14px;
    margin-bottom: 24px;
}

.app-features-list {
    list-style: none;
    text-align: left;
}

.app-features-list li {
    padding: 10px 0;
    border-bottom: 1px solid rgba(255,255,255,0.15);
    font-size: 15px;
}

.app-features-list li:last-child {
    border-bottom: none;
}

.info-list {
    list-style: none;
}

.info-list li {
    display: flex;
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    font-size: 15px;
}

.info-list li strong {
    width: 120px;
    flex-shrink: 0;
    color: var(--text-muted);
    font-weight: 500;
}

/* Content page */
.page-hero {
    background: linear-gradient(160deg, #e8f0fe, #f5f8fc);
    padding: 48px 0;
    text-align: center;
}

.page-hero h1 {
    font-size: 36px;
    font-weight: 700;
}

.page-hero .meta {
    color: var(--text-muted);
    font-size: 14px;
    margin-top: 8px;
}

.content-body {
    background: var(--white);
    padding: 60px 0 80px;
}

.legal-content {
    max-width: 800px;
    margin: 0 auto;
}

.legal-content h2 {
    font-size: 20px;
    font-weight: 700;
    margin: 36px 0 12px;
    color: var(--text);
}

.legal-content h2:first-child {
    margin-top: 0;
}

.legal-content p,
.legal-content li {
    color: var(--text-muted);
    font-size: 15px;
    line-height: 1.8;
    margin-bottom: 12px;
}

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

.legal-content li {
    margin-bottom: 6px;
}

/* Support */
.support-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.support-card {
    background: var(--bg);
    border-radius: 16px;
    padding: 32px;
    border: 1px solid var(--border);
}

.support-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 16px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    margin-bottom: 16px;
    font-size: 15px;
}

.contact-item .icon {
    font-size: 20px;
    flex-shrink: 0;
}

.faq-item {
    margin-bottom: 24px;
}

.faq-item h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
}

.faq-item p {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.7;
}

/* Footer */
.site-footer {
    background: #1a1a2e;
    color: rgba(255,255,255,0.6);
    padding: 48px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 32px;
}

.footer-brand .logo {
    color: white;
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 14px;
    line-height: 1.7;
}

.footer-col h4 {
    color: white;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 16px;
}

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

.footer-col li {
    margin-bottom: 10px;
}

.footer-col a {
    color: rgba(255,255,255,0.6);
    font-size: 14px;
}

.footer-col a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
}

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

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 16px 24px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow);
    }

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

    .nav-toggle {
        display: block;
    }

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

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

    .app-info-grid,
    .support-grid,
    .footer-grid {
        grid-template-columns: 1fr;
    }

    .section {
        padding: 48px 0;
    }
}