:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-hover: #1768E8;
    --text: #263041;
    --muted: #667085;
    --light: #F4F7FB;
    --line: #E5EAF2;
    --white: #FFFFFF;
    --panel: #F8FAFD;
    --radius: 24px;
    --shadow: 0 18px 45px rgba(35, 72, 147, .12);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    color: var(--text);
    background: #fff;
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,.94);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(229,234,242,.9);
}
.header-inner { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: #15233C; }
.logo-img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; box-shadow: 0 8px 20px rgba(41,128,254,.18); }
.nav-toggle { border: 0; background: #EFF5FF; color: #1A5EDB; border-radius: 14px; width: 44px; height: 44px; font-size: 22px; }
.site-nav { display: none; position: absolute; left: 16px; right: 16px; top: 72px; padding: 12px; background: #fff; border: 1px solid var(--line); border-radius: 20px; box-shadow: var(--shadow); }
.site-nav.open { display: grid; gap: 8px; }
.site-nav a { padding: 10px 12px; border-radius: 12px; color: #344054; font-size: 15px; }
.site-nav a.active, .site-nav a:hover { background: #EEF5FF; color: var(--blue); }
.section { padding: 56px 0; }
.section-title { font-size: clamp(28px, 4vw, 42px); line-height: 1.2; margin: 0 0 14px; letter-spacing: -.03em; }
.section-lead { margin: 0 0 24px; color: var(--muted); max-width: 760px; }
.eyebrow, .badge { display: inline-flex; align-items: center; gap: 8px; padding: 6px 12px; border-radius: 999px; background: #EEF5FF; color: var(--blue); font-weight: 700; font-size: 13px; }
.connection-workspace-hero { background: var(--gradient); color: #fff; padding: 56px 0 34px; position: relative; overflow: hidden; }
.connection-workspace-hero:before { content: ""; position: absolute; inset: -80px -120px auto auto; width: 320px; height: 320px; border-radius: 999px; background: rgba(255,255,255,.16); filter: blur(2px); }
.hero-grid { display: grid; gap: 28px; align-items: center; position: relative; z-index: 1; }
.hero-copy h1 { font-size: clamp(34px, 8vw, 62px); line-height: 1.05; letter-spacing: -.055em; margin: 18px 0 16px; }
.hero-copy p { color: rgba(255,255,255,.88); margin: 0 0 20px; max-width: 620px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }
.hero-tags span { padding: 8px 12px; border: 1px solid rgba(255,255,255,.28); border-radius: 999px; background: rgba(255,255,255,.12); font-size: 13px; }
.download-btn { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 12px 22px; background: var(--blue); color: #fff; border-radius: 999px; font-weight: 800; box-shadow: 0 12px 26px rgba(41,128,254,.25); transition: transform .2s ease, background .2s ease; }
.download-btn:hover { background: var(--blue-hover); transform: translateY(-2px); color: #fff; }
.hero-visual { position: relative; padding: 16px; border-radius: 32px; background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.26); }
.hero-device { border-radius: 26px; margin: 0 auto; box-shadow: 0 22px 55px rgba(16,24,40,.22); max-height: 420px; object-fit: contain; }
.status-panel { background: rgba(255,255,255,.95); color: var(--text); border-radius: 24px; padding: 18px; box-shadow: var(--shadow); border: 1px solid rgba(255,255,255,.45); }
.hero-visual .status-panel { margin-top: 14px; }
.status-row { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 10px 0; border-bottom: 1px solid #EEF2F7; }
.status-row:last-child { border-bottom: 0; }
.status-dot { width: 10px; height: 10px; border-radius: 50%; background: #22C55E; box-shadow: 0 0 0 6px rgba(34,197,94,.14); }
.quick-task-entries { display: grid; gap: 16px; margin-top: -26px; position: relative; z-index: 2; }
.task-card, .capability-card, .info-card, .faq-item, .risk-card, .step-card { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; box-shadow: 0 12px 35px rgba(40,64,110,.07); }
.task-card h3, .capability-card h3, .info-card h3, .risk-card h3, .step-card h3 { margin: 0 0 8px; font-size: 20px; }
.task-card p, .capability-card p, .info-card p, .risk-card p, .step-card p { color: var(--muted); margin: 0 0 12px; }
.card-link { color: var(--blue); font-weight: 800; }
.connection-capability-overview { display: grid; gap: 16px; }
.capability-card.featured { background: linear-gradient(180deg, #fff 0%, #F2F7FF 100%); }
.feature-section { padding: 60px 0; background: #fff; }
.feature-section.alt { background: var(--light); }
.feature-panel { display: grid; gap: 24px; align-items: center; background: var(--white); border: 1px solid var(--line); border-radius: 34px; padding: 24px; box-shadow: var(--shadow); }
.feature-media { background: linear-gradient(180deg, #F7FAFF, #EEF4FF); border-radius: 28px; padding: 18px; }
.feature-media img { margin: 0 auto; border-radius: 22px; max-height: 360px; object-fit: contain; }
.point-list { display: grid; gap: 10px; padding: 0; margin: 20px 0; list-style: none; }
.point-list li { padding-left: 28px; position: relative; color: #475467; }
.point-list li:before { content: ""; position: absolute; left: 0; top: 10px; width: 10px; height: 10px; border-radius: 50%; background: var(--blue); }
.tunnel-cards, .data-grid, .scenario-grid, .risk-grid, .faq-grid, .assist-grid { display: grid; gap: 16px; }
.encrypted-tunnel-section .feature-panel { background: linear-gradient(180deg, #fff, #F8FBFF); }
.line-state { display: grid; gap: 12px; margin-top: 16px; }
.line-state div { background: #F7FAFF; border: 1px solid #E6EEF9; border-radius: 18px; padding: 14px; }
.process-steps { display: grid; gap: 14px; }
.step-number { display: inline-flex; width: 34px; height: 34px; align-items: center; justify-content: center; border-radius: 12px; background: var(--blue); color: #fff; font-weight: 800; margin-bottom: 12px; }
.risk-card { border-left: 4px solid var(--blue); }
.cta-section { padding: 58px 0; background: var(--gradient); color: #fff; text-align: center; }
.cta-card { max-width: 760px; margin: 0 auto; }
.cta-card p { color: rgba(255,255,255,.88); }
.page-hero { padding: 54px 0 30px; background: linear-gradient(180deg, #F6F9FF 0%, #fff 100%); border-bottom: 1px solid var(--line); }
.page-hero h1 { margin: 16px 0 12px; font-size: clamp(30px, 6vw, 48px); line-height: 1.12; letter-spacing: -.04em; }
.page-hero p { color: var(--muted); max-width: 760px; margin: 0; }
.content-layout { display: grid; gap: 22px; padding: 44px 0 64px; }
.article-card { background: #fff; border: 1px solid var(--line); border-radius: 28px; padding: 24px; box-shadow: 0 12px 35px rgba(40,64,110,.06); }
.article-card h2 { margin-top: 0; font-size: 26px; }
.article-card p { color: #4B5565; }
.side-panel { background: var(--panel); border: 1px solid var(--line); border-radius: 26px; padding: 22px; align-self: start; }
.side-panel h3 { margin-top: 0; }
.check-list { padding-left: 0; list-style: none; display: grid; gap: 10px; }
.check-list li { border: 1px solid var(--line); background: #fff; border-radius: 16px; padding: 12px 14px; color: #475467; }
.download-page-card { text-align: center; background: #fff; border: 1px solid var(--line); border-radius: 34px; padding: 32px 20px; box-shadow: var(--shadow); }
.download-page-card .download-btn { margin: 16px 0 6px; }
.faq-item h3 { margin-top: 0; }
.site-footer { background: #192234; color: #D0D5DD; padding: 42px 0 22px; }
.footer-grid { display: grid; gap: 24px; }
.footer-brand { color: #fff; font-size: 22px; font-weight: 800; margin-bottom: 10px; }
.site-footer h3 { color: #fff; margin: 0 0 12px; }
.site-footer a { display: block; color: #D0D5DD; margin: 8px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); margin-top: 28px; padding-top: 18px; font-size: 14px; color: #98A2B3; }
@media (min-width: 640px) {
    .quick-task-entries, .connection-capability-overview, .tunnel-cards, .data-grid, .scenario-grid, .risk-grid, .faq-grid, .assist-grid, .process-steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
    .nav-toggle { display: none; }
    .site-nav { display: flex; position: static; padding: 0; border: 0; border-radius: 0; box-shadow: none; background: transparent; align-items: center; gap: 2px; }
    .site-nav a { font-size: 14px; padding: 9px 10px; }
    .hero-grid { grid-template-columns: 1.04fr .96fr; }
    .hero-visual .status-panel { position: absolute; right: -8px; bottom: 10px; width: 260px; margin-top: 0; }
    .quick-task-entries { grid-template-columns: repeat(4, 1fr); }
    .connection-capability-overview { grid-template-columns: repeat(4, 1fr); }
    .capability-card.featured { grid-column: span 2; min-height: 220px; }
    .feature-panel { grid-template-columns: 1fr 1fr; padding: 34px; }
    .encrypted-tunnel-section .feature-panel { grid-template-columns: 1.1fr .9fr; }
    .data-grid, .scenario-grid { grid-template-columns: repeat(3, 1fr); }
    .risk-grid { grid-template-columns: repeat(4, 1fr); }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .content-layout { grid-template-columns: minmax(0, 1fr) 320px; }
    .footer-grid { grid-template-columns: 1.5fr 1fr 1fr 1fr; }
}
@media (min-width: 1100px) {
    .site-nav a { padding: 10px 12px; }
    .section { padding: 72px 0; }
}