/* ===== CSS Reset & Base ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    font-size: 16px;
    line-height: 1.7;
    color: #333;
    background-color: #f8f9fa;
}

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

a {
    color: #1a73e8;
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #ff6b35;
}

/* ===== Headings ===== */
h1, h2, h3, h4, h5, h6 {
    color: #1a1a2e;
    line-height: 1.3;
    margin-bottom: 0.6em;
    font-weight: 700;
}

h1 { font-size: 1.75rem; margin-top: 0.5rem; }
h2 { font-size: 1.5rem; margin-top: 1.5rem; }
h3 { font-size: 1.25rem; margin-top: 1.2rem; }
h4 { font-size: 1.1rem; margin-top: 1rem; }
h5 { font-size: 1rem; margin-top: 0.8rem; }
h6 { font-size: 0.9rem; margin-top: 0.6rem; }

p { margin-bottom: 1em; }

/* ===== Container ===== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

/* ===== Announcement Bar ===== */
.announcement-bar {
    background: linear-gradient(135deg, #ff6b35, #ff8c42);
    color: #fff;
    text-align: center;
    padding: 10px 16px;
    font-size: 14px;
    font-weight: 500;
}

.announcement-bar a {
    color: #fff;
    text-decoration: underline;
    font-weight: 700;
}

/* ===== Navigation ===== */
.site-header {
    position: sticky;
    top: 0;
    background: #fff;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    z-index: 1000;
}

.site-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    max-width: 1200px;
    margin: 0 auto;
    flex-wrap: wrap;
}

.nav-logo {
    font-size: 1.4rem;
    font-weight: 800;
    color: #1a73e8;
    white-space: nowrap;
}

.nav-logo:hover { color: #1557b0; }

.nav-links {
    display: flex;
    list-style: none;
    gap: 4px;
    flex-wrap: wrap;
    justify-content: center;
}

.nav-links li a {
    display: inline-block;
    padding: 10px 12px;
    color: #333;
    font-size: 15px;
    font-weight: 500;
    border-radius: 6px;
    transition: background 0.2s, color 0.2s;
    min-height: 48px;
    min-width: 48px;
    text-align: center;
    line-height: 28px;
}

.nav-links li a:hover,
.nav-links li a.active {
    background: #e8f0fe;
    color: #1a73e8;
}

/* ===== Buttons / CTA ===== */
.btn {
    display: inline-block;
    padding: 14px 32px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 8px;
    text-align: center;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
    min-height: 48px;
    min-width: 48px;
    border: none;
    text-decoration: none;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.15);
}

.btn-primary {
    background: #1a73e8;
    color: #fff;
}

.btn-primary:hover {
    background: #1557b0;
    color: #fff;
}

.btn-accent {
    background: #ff6b35;
    color: #fff;
}

.btn-accent:hover {
    background: #e55a25;
    color: #fff;
}

.btn-outline {
    background: transparent;
    color: #1a73e8;
    border: 2px solid #1a73e8;
}

.btn-outline:hover {
    background: #1a73e8;
    color: #fff;
}

/* ===== Hero Section ===== */
.hero {
    background: linear-gradient(135deg, #1a73e8 0%, #0d47a1 100%);
    color: #fff;
    padding: 60px 16px;
    text-align: center;
}

.hero h1 {
    color: #fff;
    font-size: 1.75rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1rem;
    opacity: 0.95;
    max-width: 700px;
    margin: 0 auto 1.5rem;
}

.hero .btn {
    margin: 8px;
}

/* ===== Section ===== */
.section {
    padding: 48px 16px;
}

.section-alt {
    background: #fff;
}

.section-title {
    text-align: center;
    margin-bottom: 2rem;
}

.section-title h2 {
    font-size: 1.5rem;
}

.section-title p {
    color: #666;
    max-width: 600px;
    margin: 0.5rem auto 0;
}

/* ===== Trust Badges ===== */
.trust-badges {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 24px;
    padding: 32px 16px;
    background: #fff;
}

.trust-badge {
    text-align: center;
    min-width: 120px;
}

.trust-badge .badge-icon {
    font-size: 2rem;
    margin-bottom: 8px;
}

.trust-badge .badge-text {
    font-size: 14px;
    color: #555;
    font-weight: 500;
}

.trust-badge .badge-value {
    font-size: 1.5rem;
    font-weight: 800;
    color: #1a73e8;
}

/* ===== Feature Cards ===== */
.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: #fff;
    border-radius: 12px;
    padding: 32px 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    transition: transform 0.2s, box-shadow 0.2s;
    text-align: center;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.1);
}

.feature-card .card-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.feature-card p {
    color: #555;
    font-size: 15px;
}

/* ===== Pricing Table ===== */
.pricing-table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin: 0 auto;
    max-width: 1200px;
}

.pricing-table {
    width: 100%;
    min-width: 600px;
    border-collapse: collapse;
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}

.pricing-table th,
.pricing-table td {
    padding: 16px 14px;
    text-align: center;
    border-bottom: 1px solid #eee;
    font-size: 15px;
}

.pricing-table thead th {
    background: #1a73e8;
    color: #fff;
    font-weight: 700;
    font-size: 16px;
}

.pricing-table tbody tr:hover {
    background: #f0f7ff;
}

.pricing-table .highlight-col {
    background: #e8f0fe;
    font-weight: 600;
}

.pricing-table .price {
    font-size: 1.4rem;
    font-weight: 800;
    color: #ff6b35;
}

.pricing-cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: #fff;
    border-radius: 12px;
    padding: 32px 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    text-align: center;
    border: 2px solid transparent;
    transition: border-color 0.2s, transform 0.2s;
}

.pricing-card:hover {
    border-color: #1a73e8;
    transform: translateY(-4px);
}

.pricing-card.popular {
    border-color: #ff6b35;
    position: relative;
}

.pricing-card.popular::before {
    content: "最受欢迎";
    position: absolute;
    top: -14px;
    left: 50%;
    transform: translateX(-50%);
    background: #ff6b35;
    color: #fff;
    padding: 4px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
}

.pricing-card h3 {
    font-size: 1.3rem;
    margin-bottom: 8px;
}

.pricing-card .card-price {
    font-size: 2rem;
    font-weight: 800;
    color: #ff6b35;
    margin: 16px 0;
}

.pricing-card .card-price small {
    font-size: 0.9rem;
    color: #888;
    font-weight: 400;
}

.pricing-card ul {
    list-style: none;
    margin: 16px 0 24px;
    text-align: left;
}

.pricing-card ul li {
    padding: 8px 0;
    border-bottom: 1px solid #f0f0f0;
    font-size: 15px;
    color: #555;
}

.pricing-card ul li::before {
    content: "✓ ";
    color: #34a853;
    font-weight: 700;
}

/* ===== Nodes Section ===== */
.nodes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 16px;
    max-width: 1000px;
    margin: 0 auto;
}

.node-item {
    background: #fff;
    border-radius: 10px;
    padding: 20px 12px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    transition: transform 0.2s;
}

.node-item:hover {
    transform: translateY(-3px);
}

.node-item .node-flag {
    font-size: 2rem;
    margin-bottom: 8px;
}

.node-item .node-name {
    font-size: 14px;
    font-weight: 600;
    color: #333;
}

/* ===== Steps ===== */
.steps {
    max-width: 800px;
    margin: 0 auto;
    counter-reset: step-counter;
}

.step {
    display: flex;
    gap: 20px;
    margin-bottom: 32px;
    align-items: flex-start;
}

.step-number {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    background: #1a73e8;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
}

.step-content h3 {
    font-size: 1.1rem;
    margin-bottom: 6px;
}

.step-content p {
    color: #555;
    font-size: 15px;
}

/* ===== Reviews ===== */
.reviews-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    max-width: 1000px;
    margin: 0 auto;
}

.review-card {
    background: #fff;
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
}

.review-card blockquote {
    font-style: italic;
    color: #444;
    border-left: 4px solid #1a73e8;
    padding-left: 16px;
    margin-bottom: 16px;
    font-size: 15px;
    line-height: 1.7;
}

.review-card .reviewer {
    font-weight: 600;
    color: #1a73e8;
    font-size: 14px;
}

.review-card .stars {
    color: #fbbc04;
    font-size: 1rem;
    margin-bottom: 8px;
}

/* ===== FAQ ===== */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    border-radius: 10px;
    padding: 24px;
    margin-bottom: 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.faq-item dt {
    font-weight: 700;
    font-size: 1rem;
    color: #1a1a2e;
    margin-bottom: 12px;
    padding-left: 28px;
    position: relative;
}

.faq-item dt::before {
    content: "Q";
    position: absolute;
    left: 0;
    top: 0;
    width: 22px;
    height: 22px;
    background: #1a73e8;
    color: #fff;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
}

.faq-item dd {
    color: #555;
    font-size: 15px;
    line-height: 1.8;
    padding-left: 28px;
}

.faq-item dd ol,
.faq-item dd ul {
    margin: 8px 0 8px 20px;
}

.faq-item dd li {
    margin-bottom: 6px;
}

/* ===== CTA Section ===== */
.cta-section {
    background: linear-gradient(135deg, #1a73e8 0%, #0d47a1 100%);
    color: #fff;
    text-align: center;
    padding: 48px 16px;
}

.cta-section h2 {
    color: #fff;
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.cta-section p {
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto 1.5rem;
}

.cta-section .btn {
    margin: 8px;
}

/* ===== Download Cards ===== */
.download-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    max-width: 900px;
    margin: 0 auto;
}

.download-card {
    background: #fff;
    border-radius: 12px;
    padding: 28px 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    display: flex;
    align-items: center;
    gap: 20px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.download-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}

.download-card .dl-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
}

.download-card .dl-info h3 {
    font-size: 1.1rem;
    margin-bottom: 4px;
}

.download-card .dl-info p {
    font-size: 14px;
    color: #666;
    margin-bottom: 8px;
}

/* ===== Help Section ===== */
.help-topics {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    max-width: 900px;
    margin: 0 auto;
}

.help-topic {
    background: #fff;
    border-radius: 10px;
    padding: 24px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

.help-topic h3 {
    font-size: 1.1rem;
    margin-bottom: 8px;
    color: #1a73e8;
}

.help-topic p {
    color: #555;
    font-size: 15px;
}

/* ===== Stats ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    max-width: 800px;
    margin: 0 auto;
}

.stat-item {
    text-align: center;
    background: #fff;
    border-radius: 12px;
    padding: 28px 16px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
}

.stat-item .stat-value {
    font-size: 2rem;
    font-weight: 800;
    color: #1a73e8;
}

.stat-item .stat-label {
    font-size: 14px;
    color: #666;
    margin-top: 4px;
}

/* ===== Legal / Policy Content ===== */
.legal-content {
    max-width: 800px;
    margin: 0 auto;
    background: #fff;
    border-radius: 12px;
    padding: 32px 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.legal-content h2 {
    font-size: 1.3rem;
    margin-top: 2rem;
    padding-bottom: 8px;
    border-bottom: 2px solid #e8f0fe;
}

.legal-content h3 {
    font-size: 1.1rem;
    margin-top: 1.5rem;
}

.legal-content p,
.legal-content li {
    color: #444;
    font-size: 15px;
    line-height: 1.8;
}

.legal-content ul,
.legal-content ol {
    margin: 12px 0 12px 24px;
}

.legal-content li {
    margin-bottom: 8px;
}

/* ===== Footer ===== */
.site-footer {
    background: #1a1a2e;
    color: #aaa;
    padding: 48px 16px 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-col h4 {
    color: #fff;
    font-size: 1rem;
    margin-bottom: 16px;
}

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

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

.footer-col ul li a {
    color: #aaa;
    font-size: 14px;
    transition: color 0.2s;
    display: inline-block;
    min-height: 32px;
    line-height: 32px;
}

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

.footer-bottom {
    text-align: center;
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid #333;
}

.footer-bottom p {
    font-size: 13px;
    color: #777;
    margin-bottom: 6px;
}

.footer-bottom .footer-desc {
    font-size: 13px;
    color: #666;
}

/* ===== Responsive: Tablet (768px) ===== */
@media (min-width: 768px) {
    h1 { font-size: 2.2rem; }
    h2 { font-size: 1.8rem; }
    h3 { font-size: 1.4rem; }

    .hero { padding: 80px 16px; }
    .hero h1 { font-size: 2.4rem; }
    .hero p { font-size: 1.15rem; }

    .section { padding: 64px 16px; }
    .section-title h2 { font-size: 1.8rem; }

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

    .pricing-cards {
        grid-template-columns: repeat(3, 1fr);
    }

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

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

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

    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .nav-links li a {
        padding: 10px 14px;
        font-size: 15px;
    }
}

/* ===== Responsive: Desktop (1024px) ===== */
@media (min-width: 1024px) {
    h1 { font-size: 2.6rem; }
    h2 { font-size: 2rem; }

    .hero { padding: 100px 16px; }
    .hero h1 { font-size: 2.8rem; }
    .hero p { font-size: 1.2rem; max-width: 750px; }

    .section { padding: 80px 16px; }

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

    .nodes-grid {
        grid-template-columns: repeat(6, 1fr);
    }

    .download-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .reviews-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .nav-links li a {
        padding: 10px 16px;
        font-size: 16px;
    }

    .site-nav {
        padding: 14px 24px;
    }
}

/* ===== Nodes List (for index.html) ===== */
.nodes-list {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    max-width: 1000px;
    margin: 24px auto;
}

.node-tag {
    background: #fff;
    border: 1px solid #e0e0e0;
    border-radius: 20px;
    padding: 8px 16px;
    font-size: 14px;
    color: #555;
    transition: all 0.2s;
}

.node-tag:hover {
    background: #1a73e8;
    color: #fff;
    border-color: #1a73e8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.2);
}

.nodes-description {
    text-align: center;
    color: #666;
    font-size: 15px;
    margin-bottom: 16px;
}

.nodes-cta-text {
    text-align: center;
    color: #555;
    font-size: 15px;
    margin: 24px 0 16px;
}

.cta-button {
    display: inline-block;
    padding: 14px 32px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 8px;
    text-align: center;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
    background: #ff6b35;
    color: #fff;
    text-decoration: none;
}

.cta-button:hover {
    background: #e55a25;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 53, 0.3);
    color: #fff;
}

.cta-large {
    padding: 16px 40px;
    font-size: 18px;
}

/* ===== Guide Section ===== */
.steps-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.step-item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    background: #fff;
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.step-item .step-number {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    background: #1a73e8;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    font-weight: 700;
}

.step-item h3 {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.step-item p {
    color: #555;
    font-size: 15px;
    line-height: 1.7;
}

/* ===== Reviews Section ===== */
.reviews-grid blockquote {
    background: #fff;
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    margin: 0;
}

.reviews-grid blockquote p {
    font-style: italic;
    color: #444;
    font-size: 15px;
    line-height: 1.7;
    margin-bottom: 12px;
}

.reviews-grid blockquote cite {
    color: #1a73e8;
    font-weight: 600;
    font-size: 14px;
    font-style: normal;
}

/* ===== FAQ Section ===== */
.faq-list dt {
    background: #fff;
    border-radius: 10px 10px 0 0;
    padding: 20px 24px 12px;
    margin-bottom: 0;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.faq-list dt h3 {
    font-size: 1rem;
    margin: 0;
    color: #1a1a2e;
}

.faq-list dd {
    background: #fff;
    border-radius: 0 0 10px 10px;
    padding: 0 24px 24px;
    margin: 0 0 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.faq-list dd p {
    color: #555;
    font-size: 15px;
    line-height: 1.8;
    margin-bottom: 12px;
}

.faq-list dd ol,
.faq-list dd ul {
    margin: 8px 0 8px 20px;
}

.faq-list dd li {
    margin-bottom: 6px;
    color: #555;
    font-size: 15px;
}

/* ===== Bottom CTA ===== */
.bottom-cta {
    background: linear-gradient(135deg, #1a73e8 0%, #0d47a1 100%);
    color: #fff;
    text-align: center;
    padding: 60px 16px;
}

.bottom-cta h2 {
    color: #fff;
    font-size: 1.6rem;
    margin-bottom: 1.5rem;
}

/* ===== Main Footer ===== */
.main-footer {
    background: #1a1a2e;
    color: #aaa;
    padding: 48px 16px 24px;
}

.footer-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-section h4 {
    color: #fff;
    font-size: 1rem;
    margin-bottom: 16px;
}

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

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

.footer-section ul li a {
    color: #aaa;
    font-size: 14px;
    transition: color 0.2s;
}

.footer-section ul li a:hover {
    color: #fff;
}

.footer-about p {
    font-size: 14px;
    color: #888;
    line-height: 1.6;
}

.footer-bottom {
    text-align: center;
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid #333;
}

.footer-bottom p {
    font-size: 13px;
    color: #777;
    margin-bottom: 0;
}

.footer-bottom a {
    color: #aaa;
}

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

/* ===== Responsive for new sections ===== */
@media (min-width: 768px) {
    .steps-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .reviews-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (min-width: 1024px) {
    .reviews-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ===== Utility ===== */
.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }