* {
    box-sizing: border-box;
}

:root {
    --gradient-main: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1E2430;
    --muted: #687083;
    --light: #F4F7FB;
    --line: #E5EAF2;
    --panel: #FFFFFF;
    --soft-blue: #EEF5FF;
    --shadow: 0 18px 50px rgba(37, 63, 130, 0.10);
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    color: var(--text);
    background: #F8FAFD;
    line-height: 1.7;
    overflow-x: hidden;
}

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

a {
    color: inherit;
    text-decoration: none;
}

.container {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.94);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
}

.header-inner {
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
    padding: 12px 0;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 18px;
    white-space: nowrap;
}

.logo-img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    object-fit: cover;
}

.site-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 8px;
}

.site-nav a {
    color: #4B5568;
    font-size: 14px;
    padding: 8px 10px;
    border-radius: 999px;
}

.site-nav a:hover,
.site-nav a.active {
    background: var(--soft-blue);
    color: var(--blue);
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 26px;
    border-radius: 999px;
    color: #fff;
    background: var(--blue);
    font-weight: 800;
    box-shadow: 0 14px 30px rgba(41, 128, 254, 0.24);
    transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 18px 34px rgba(23, 104, 232, 0.26);
}

.section {
    padding: 64px 0;
}

.section.alt {
    background: #F1F5FA;
}

.section-head {
    margin-bottom: 28px;
}

.section-kicker,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--blue);
    background: var(--soft-blue);
    border: 1px solid #DCEAFF;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 800;
}

.section h2,
.page-title h1,
.connection-workspace-hero h1 {
    letter-spacing: -0.03em;
    line-height: 1.18;
}

.section h2 {
    font-size: clamp(28px, 4vw, 42px);
    margin: 14px 0 12px;
}

.section-desc,
.lead,
.card p,
.feature-panel p,
.page-title p {
    color: var(--muted);
}

.connection-workspace-hero {
    margin: 24px auto 0;
    padding: 54px 0;
    color: #fff;
    background: var(--gradient-main);
    border-radius: 0 0 34px 34px;
    overflow: hidden;
    position: relative;
}

.connection-workspace-hero::before,
.cta-section::before {
    content: "";
    position: absolute;
    width: 420px;
    height: 420px;
    border-radius: 50%;
    background: rgba(255,255,255,0.12);
    right: -120px;
    top: -180px;
}

.hero-grid {
    position: relative;
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    align-items: center;
}

.connection-workspace-hero h1 {
    font-size: clamp(36px, 8vw, 64px);
    margin: 0 0 18px;
}

.hero-copy p {
    color: rgba(255,255,255,0.88);
    max-width: 620px;
    margin: 0 0 24px;
    font-size: 17px;
}

.hero-tags,
.status-row,
.tunnel-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.hero-tags span,
.status-row span,
.tunnel-tags span {
    border-radius: 999px;
    padding: 8px 12px;
    background: rgba(255,255,255,0.15);
    border: 1px solid rgba(255,255,255,0.22);
    color: #fff;
    font-size: 13px;
    font-weight: 700;
}

.hero-card {
    position: relative;
    min-height: 420px;
    border-radius: 32px;
    padding: 18px;
    background: rgba(255,255,255,0.18);
    border: 1px solid rgba(255,255,255,0.24);
    box-shadow: 0 30px 70px rgba(31, 42, 110, 0.22);
}

.hero-card img {
    width: min(420px, 92%);
    margin: 0 auto;
    filter: drop-shadow(0 28px 40px rgba(20, 32, 80, 0.24));
}

.status-panel {
    background: rgba(255,255,255,0.94);
    color: var(--text);
    border-radius: 26px;
    padding: 18px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(255,255,255,0.75);
}

.hero-status {
    margin-top: -28px;
    position: relative;
}

.status-line {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding: 11px 0;
    border-bottom: 1px solid var(--line);
    color: #566070;
}

.status-line:last-child {
    border-bottom: 0;
}

.status-line strong {
    color: var(--blue);
}

.quick-task-entries,
.risk-grid,
.faq-grid,
.card-grid,
.scenario-grid,
.boundary-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.card,
.task-card,
.capability-card,
.feature-panel,
.faq-item,
.risk-card,
.step-card,
.note-panel {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 22px;
    box-shadow: 0 10px 30px rgba(35, 51, 92, 0.06);
}

.task-card {
    position: relative;
    overflow: hidden;
}

.task-card::before,
.risk-card::before {
    content: "";
    display: block;
    width: 44px;
    height: 4px;
    border-radius: 99px;
    background: var(--blue);
    margin-bottom: 14px;
}

.task-card h3,
.capability-card h3,
.feature-panel h3,
.risk-card h3,
.step-card h3,
.faq-item h3 {
    margin: 0 0 8px;
    font-size: 20px;
}

.text-link {
    display: inline-flex;
    align-items: center;
    margin-top: 10px;
    color: var(--blue);
    font-weight: 800;
}

.connection-capability-overview {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.capability-card.large {
    background: linear-gradient(135deg, #FFFFFF 0%, #EFF5FF 100%);
}

.capability-card .mini-label {
    color: var(--blue);
    font-size: 13px;
    font-weight: 800;
}

.split-panel,
.quick-connect-section,
.route-optimization-section,
.device-protection-section,
.connection-checkup-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    align-items: center;
}

.visual-card {
    border-radius: 34px;
    background: #fff;
    border: 1px solid var(--line);
    padding: 20px;
    box-shadow: var(--shadow);
}

.visual-card.soft {
    background: linear-gradient(145deg, #FFFFFF, #F0F6FF);
}

.feature-list,
.clean-list,
.check-list {
    padding: 0;
    margin: 18px 0 0;
    list-style: none;
}

.feature-list li,
.clean-list li,
.check-list li {
    position: relative;
    padding: 10px 0 10px 28px;
    color: #4E586B;
    border-bottom: 1px solid #EEF2F7;
}

.feature-list li::before,
.clean-list li::before,
.check-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 18px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--blue);
}

.encrypted-tunnel-section {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 26px;
    box-shadow: var(--shadow);
}

.tunnel-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: center;
}

.tunnel-card-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
    margin-top: 20px;
}

.tunnel-mini {
    border-radius: 20px;
    background: #F6F9FD;
    border: 1px solid var(--line);
    padding: 18px;
}

.route-status {
    display: grid;
    gap: 14px;
}

.route-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.route-bar {
    width: 42%;
    height: 8px;
    border-radius: 99px;
    background: linear-gradient(90deg, #C8DCFF, #2980FE);
}

.device-stack {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.device-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 22px;
    padding: 18px;
}

.data-boundary-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.process-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    counter-reset: steps;
}

.step-card {
    counter-increment: steps;
}

.step-card::before {
    content: counter(steps, decimal-leading-zero);
    display: inline-flex;
    width: 42px;
    height: 42px;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: var(--soft-blue);
    color: var(--blue);
    font-weight: 900;
    margin-bottom: 14px;
}

.faq-item details {
    margin-top: 0;
}

.faq-item summary {
    cursor: pointer;
    font-weight: 800;
    color: var(--text);
}

.faq-item p {
    margin-bottom: 0;
}

.cta-section {
    position: relative;
    overflow: hidden;
    margin: 64px auto;
    color: #fff;
    background: var(--gradient-main);
    border-radius: 34px;
    padding: 42px 24px;
    text-align: center;
}

.cta-section h2,
.cta-section p,
.cta-section .download-btn {
    position: relative;
}

.cta-section p {
    color: rgba(255,255,255,0.86);
    max-width: 680px;
    margin: 0 auto 22px;
}

.page-title {
    padding: 58px 0 26px;
}

.page-title h1 {
    font-size: clamp(34px, 6vw, 54px);
    margin: 14px 0 12px;
}

.page-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    padding-bottom: 64px;
}

.article-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.article-panel h2 {
    font-size: 26px;
    margin-top: 28px;
}

.article-panel h2:first-child {
    margin-top: 0;
}

.side-panel {
    display: grid;
    gap: 16px;
    align-content: start;
}

.info-strip {
    border-left: 4px solid var(--blue);
    background: #F6F9FF;
    border-radius: 18px;
    padding: 18px;
    color: #4B5568;
}

.download-page-card {
    text-align: center;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 34px;
    box-shadow: var(--shadow);
}

.download-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
    margin-top: 28px;
    text-align: left;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 42px 0 26px;
}

.site-footer {
    background: #111827;
    color: #D4DBE8;
}

.site-footer h3,
.footer-brand {
    color: #fff;
    margin: 0 0 10px;
}

.footer-brand {
    font-size: 22px;
    font-weight: 900;
}

.site-footer a {
    display: block;
    color: #B9C2D2;
    margin: 7px 0;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.12);
    padding: 18px 0 28px;
    color: #AEB8C8;
    font-size: 14px;
}

@media (min-width: 640px) {
    .quick-task-entries,
    .risk-grid,
    .card-grid,
    .scenario-grid,
    .boundary-grid,
    .download-steps {
        grid-template-columns: repeat(2, 1fr);
    }
    .process-steps {
        grid-template-columns: repeat(2, 1fr);
    }
    .tunnel-card-row {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 900px) {
    .header-inner {
        min-height: 78px;
    }
    .hero-grid {
        grid-template-columns: 1.02fr 0.98fr;
    }
    .connection-workspace-hero {
        padding: 78px 0;
    }
    .quick-task-entries {
        grid-template-columns: repeat(4, 1fr);
    }
    .connection-capability-overview {
        grid-template-columns: repeat(4, 1fr);
    }
    .capability-card.large {
        grid-column: span 2;
        min-height: 220px;
    }
    .quick-connect-section,
    .route-optimization-section,
    .device-protection-section,
    .connection-checkup-section,
    .split-panel,
    .tunnel-layout {
        grid-template-columns: 1fr 1fr;
    }
    .data-boundary-section {
        grid-template-columns: 0.9fr 1.1fr;
    }
    .risk-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    .faq-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .process-steps {
        grid-template-columns: repeat(3, 1fr);
    }
    .page-layout {
        grid-template-columns: minmax(0, 1fr) 320px;
    }
    .article-panel {
        padding: 34px;
    }
    .footer-grid {
        grid-template-columns: 1.4fr 1fr 1fr 1fr;
    }
    .device-stack {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 720px) {
    .container {
        width: min(100% - 24px, 1120px);
    }
    .header-inner {
        align-items: flex-start;
        flex-direction: column;
    }
    .site-nav {
        justify-content: flex-start;
        width: 100%;
    }
    .site-nav a {
        font-size: 13px;
        padding: 7px 9px;
        background: #F5F7FA;
    }
    .section {
        padding: 46px 0;
    }
    .hero-card {
        min-height: auto;
    }
    .download-btn {
        width: 100%;
        max-width: 320px;
    }
    .cta-section .download-btn,
    .download-page-card .download-btn {
        max-width: 100%;
    }
}