:root{
  --gradient:linear-gradient(90deg,#3558F2 0%,#7B4EF1 50%,#B84DDA 100%);
  --blue:#2980FE;
  --blue-hover:#1768E8;
  --ink:#18233A;
  --muted:#667085;
  --light:#F5F7FB;
  --line:#E6EAF2;
  --panel:#FFFFFF;
  --radius:28px;
  --shadow:0 18px 50px rgba(37,64,122,.12);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",Arial,sans-serif;color:var(--ink);background:#fff;line-height:1.72;overflow-x:hidden}
a{color:inherit;text-decoration:none}
img{max-width:100%;height:auto;display:block}
p{margin:0 0 16px;color:#4B5565}
strong{color:#18233A}
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:blur(18px);border-bottom:1px solid rgba(230,234,242,.82)}
.header-inner{max-width:1180px;margin:0 auto;padding:14px 18px;display:flex;align-items:center;justify-content:space-between;gap:18px}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;color:#17213A;white-space:nowrap}
.logo-img{width:38px;height:38px;border-radius:12px;object-fit:cover;box-shadow:0 8px 20px rgba(41,128,254,.14)}
.brand-text{font-size:18px;letter-spacing:.2px}
.site-nav{display:none;flex-direction:column;position:absolute;left:14px;right:14px;top:68px;padding:14px;background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:var(--shadow)}
.site-nav.open{display:flex}
.site-nav a{padding:10px 12px;border-radius:14px;color:#4B5565;font-size:14px;font-weight:600}
.site-nav a:hover,.site-nav a.active{color:#1768E8;background:#EEF5FF}
.nav-toggle{border:0;background:#EEF5FF;border-radius:14px;width:44px;height:40px;display:grid;place-content:center;gap:4px;cursor:pointer}
.nav-toggle span{display:block;width:20px;height:2px;background:#1E4ED8;border-radius:2px}
.container{width:min(1120px,calc(100% - 36px));margin:0 auto}
.narrow{width:min(900px,calc(100% - 36px));margin:0 auto}
.section{padding:72px 0}
.section-soft{background:var(--light)}
.section-title{font-size:30px;line-height:1.22;margin:0 0 14px;letter-spacing:-.5px;color:#101828}
.section-lead{font-size:16px;color:#667085;max-width:780px;margin-bottom:26px}
.badge{display:inline-flex;align-items:center;gap:8px;padding:7px 12px;border-radius:999px;background:#EEF5FF;color:#1768E8;font-size:13px;font-weight:700;margin-bottom:16px}
.download-btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:12px 22px;border-radius:999px;background:var(--blue);color:#fff!important;font-weight:800;box-shadow:0 12px 28px rgba(41,128,254,.28);transition:.2s ease;border:0;white-space:nowrap}
.download-btn:hover{background:var(--blue-hover);transform:translateY(-1px);box-shadow:0 16px 32px rgba(23,104,232,.3)}
.text-link{color:#1768E8;font-weight:800;border-bottom:1px solid rgba(41,128,254,.25)}
.vpn-saas-hero{position:relative;overflow:hidden;padding:64px 0 46px;background:#F7F9FF}
.hero-shell{position:relative;border-radius:36px;background:var(--gradient);padding:34px 20px;color:#fff;overflow:hidden;box-shadow:0 28px 70px rgba(73,78,190,.25)}
.hero-shell:before{content:"";position:absolute;inset:-30% -10% auto auto;width:70%;height:140%;background:rgba(255,255,255,.16);transform:skewX(-18deg);border-radius:48px}
.hero-grid{position:relative;display:grid;grid-template-columns:1fr;gap:26px;align-items:center}
.hero-copy h1{font-size:38px;line-height:1.12;margin:0 0 18px;letter-spacing:-1px;color:#fff}
.hero-copy p{color:rgba(255,255,255,.88);font-size:16px;margin-bottom:22px}
.hero-tags{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px}
.hero-tags span,.visual-tag{display:inline-flex;padding:8px 12px;border-radius:999px;background:rgba(255,255,255,.18);color:#fff;border:1px solid rgba(255,255,255,.28);font-size:13px;font-weight:700;backdrop-filter:blur(12px)}
.hero-visual{position:relative;min-height:320px;display:grid;place-items:center}
.hero-card{position:relative;width:min(420px,100%);padding:20px;border-radius:32px;background:rgba(255,255,255,.2);border:1px solid rgba(255,255,255,.32);box-shadow:0 18px 50px rgba(0,0,0,.16);backdrop-filter:blur(18px)}
.hero-card img{border-radius:24px;background:#fff;box-shadow:0 16px 40px rgba(0,0,0,.14)}
.visual-tag{position:absolute;background:#fff;color:#2352E8;border-color:#fff;box-shadow:0 12px 26px rgba(20,36,80,.12)}
.tag-a{left:0;top:12px}.tag-b{right:0;top:84px}.tag-c{left:18px;bottom:56px}.tag-d{right:24px;bottom:8px}
.product-highlights{margin-top:-10px;position:relative;z-index:2}
.highlights-grid{display:grid;grid-template-columns:1fr;gap:16px}
.highlight-card{background:#fff;border:1px solid var(--line);border-radius:24px;padding:22px;box-shadow:0 12px 30px rgba(20,36,80,.06)}
.highlight-card .pill{display:inline-flex;padding:5px 10px;border-radius:999px;background:#EEF5FF;color:#2980FE;font-size:12px;font-weight:800;margin-bottom:12px}
.highlight-card h3{margin:0 0 8px;font-size:19px;color:#101828}
.highlight-card p{font-size:14px;margin-bottom:10px}
.feature-panel{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);overflow:hidden}
.feature-grid{display:grid;grid-template-columns:1fr;gap:28px;align-items:center}
.feature-image{border-radius:26px;background:linear-gradient(135deg,#EEF5FF,#FFFFFF);padding:18px;border:1px solid var(--line)}
.feature-image img{border-radius:20px;margin:auto;box-shadow:0 16px 36px rgba(32,64,120,.08)}
.bullet-grid{display:grid;grid-template-columns:1fr;gap:12px;margin:22px 0}
.bullet{padding:14px 16px;border-radius:18px;background:#F7F9FC;border:1px solid var(--line);color:#4B5565;font-size:14px}
.bullet strong{display:block;margin-bottom:4px}
.high-speed-section .feature-panel{background:linear-gradient(180deg,#FFFFFF 0%,#F6F9FF 100%)}
.speed-metrics{display:grid;grid-template-columns:1fr;gap:12px;margin-top:18px}
.metric{background:#fff;border:1px solid var(--line);border-radius:20px;padding:16px}.metric span{display:block;color:#2980FE;font-size:13px;font-weight:800}.metric strong{font-size:22px}
.node-cards{display:grid;grid-template-columns:1fr;gap:14px;margin-top:18px}
.node-card{border-radius:20px;background:#fff;border:1px solid var(--line);padding:16px;box-shadow:0 10px 26px rgba(20,36,80,.05)}
.privacy-protection-section{background:#F8FAFF}
.privacy-layout{display:grid;grid-template-columns:1fr;gap:18px;align-items:center}
.privacy-cards{display:grid;grid-template-columns:1fr;gap:14px;margin-top:18px}
.privacy-card,.policy-card,.device-card,.protocol-card,.risk-card,.faq-item,.step-card{background:#fff;border:1px solid var(--line);border-radius:22px;padding:20px;box-shadow:0 10px 28px rgba(20,36,80,.05)}
.privacy-card h3,.policy-card h3,.device-card h3,.protocol-card h3,.risk-card h3,.faq-item h3,.step-card h3{margin:0 0 8px;font-size:18px;color:#101828}
.policy-grid,.device-grid,.protocol-grid,.risk-grid,.faq-grid{display:grid;grid-template-columns:1fr;gap:16px}
.policy-card{border-top:4px solid #2980FE}
.device-card{background:linear-gradient(180deg,#fff,#F8FBFF)}
.protocol-card{position:relative;overflow:hidden}.protocol-card:before{content:"";position:absolute;left:0;right:0;top:0;height:4px;background:var(--gradient)}
.process-steps{display:grid;grid-template-columns:1fr;gap:14px;counter-reset:step}
.step-card{position:relative;padding-left:72px}.step-card:before{counter-increment:step;content:counter(step);position:absolute;left:20px;top:20px;width:36px;height:36px;border-radius:14px;background:#EEF5FF;color:#1768E8;display:grid;place-items:center;font-weight:900}
.risk-card{border-left:4px solid #2980FE}.risk-card span{display:block;color:#667085;font-size:14px;margin-top:8px}
.faq-item p{font-size:15px}.faq-item summary{cursor:pointer;font-weight:800;color:#101828}.faq-item details[open] summary{color:#1768E8}
.cta-section{padding:76px 0;background:#fff}.cta-box{position:relative;overflow:hidden;border-radius:36px;background:var(--gradient);padding:34px 22px;text-align:center;color:#fff;box-shadow:0 28px 70px rgba(73,78,190,.2)}.cta-box h2{font-size:30px;margin:0 0 10px;color:#fff}.cta-box p{color:rgba(255,255,255,.86);max-width:680px;margin:0 auto 22px}.cta-box .download-btn{background:#2980FE;color:#fff!important}.cta-box .download-btn:hover{background:#1768E8}
.page-hero{padding:64px 0 36px;background:linear-gradient(180deg,#F6F8FF 0%,#FFFFFF 100%)}
.page-hero h1{font-size:36px;line-height:1.18;margin:0 0 16px;color:#101828;letter-spacing:-.8px}.page-hero p{font-size:17px;max-width:780px}.page-actions{margin-top:22px}
.content-layout{display:grid;grid-template-columns:1fr;gap:24px;align-items:start}.article-card{background:#fff;border:1px solid var(--line);border-radius:28px;padding:24px;box-shadow:var(--shadow)}.article-card h2{font-size:24px;margin:8px 0 12px;color:#101828}.article-card h3{font-size:19px;margin:22px 0 8px;color:#101828}.article-card ul,.article-card ol{padding-left:22px;color:#4B5565}.article-card li{margin-bottom:8px}.side-panel{background:#F7F9FC;border:1px solid var(--line);border-radius:26px;padding:22px;position:sticky;top:94px}.side-panel h2,.side-panel h3{margin-top:0}.side-panel a{display:block;padding:10px 0;color:#1768E8;font-weight:700;border-bottom:1px solid #E6EAF2}.tip-box{border-radius:22px;background:#F6F9FF;border:1px solid #DCE8FF;padding:18px;margin:20px 0}.check-list{display:grid;grid-template-columns:1fr;gap:12px;margin-top:16px}.check-item{padding:14px 16px;background:#fff;border:1px solid var(--line);border-radius:18px}.download-page-card{text-align:center}.install-steps{display:grid;grid-template-columns:1fr;gap:14px;margin:26px 0}.install-step{background:#F7F9FC;border:1px solid var(--line);border-radius:20px;padding:18px}.footer-inner{max-width:1180px;margin:0 auto;padding:46px 18px;display:grid;grid-template-columns:1fr;gap:28px}.site-footer{background:#101828;color:#fff}.site-footer p,.site-footer a{color:rgba(255,255,255,.68)}.footer-brand{display:flex;gap:14px;align-items:flex-start}.footer-logo{width:46px;height:46px;border-radius:14px;object-fit:cover}.footer-links{display:grid;grid-template-columns:1fr;gap:20px}.footer-links h3{font-size:15px;margin:0 0 10px;color:#fff}.footer-links a{display:block;margin:6px 0;font-size:14px}.footer-bottom{border-top:1px solid rgba(255,255,255,.1);text-align:center;padding:18px}.footer-bottom p{margin:0;font-size:13px}
@media (min-width:700px){.highlights-grid{grid-template-columns:repeat(2,1fr)}.policy-grid,.device-grid,.protocol-grid,.risk-grid,.faq-grid{grid-template-columns:repeat(2,1fr)}.process-steps{grid-template-columns:repeat(2,1fr)}.install-steps{grid-template-columns:repeat(2,1fr)}.footer-links{grid-template-columns:repeat(3,1fr)}}
@media (min-width:960px){.nav-toggle{display:none}.site-nav{display:flex;position:static;flex-direction:row;align-items:center;padding:0;background:transparent;border:0;box-shadow:none}.site-nav a{font-size:14px;padding:8px 10px}.vpn-saas-hero{padding:76px 0 66px}.hero-shell{padding:54px}.hero-grid{grid-template-columns:1.02fr .98fr}.hero-copy h1{font-size:58px}.hero-copy p{font-size:18px;max-width:610px}.section{padding:92px 0}.section-title{font-size:40px}.highlights-grid{grid-template-columns:repeat(4,1fr)}.feature-grid{grid-template-columns:1fr 1fr}.feature-panel{padding:38px}.bullet-grid{grid-template-columns:repeat(2,1fr)}.speed-metrics{grid-template-columns:repeat(3,1fr)}.node-cards{grid-template-columns:repeat(3,1fr)}.privacy-layout{grid-template-columns:1.1fr .9fr}.privacy-cards{grid-template-columns:repeat(3,1fr)}.policy-grid,.device-grid,.protocol-grid{grid-template-columns:repeat(3,1fr)}.risk-grid{grid-template-columns:repeat(3,1fr)}.faq-grid{grid-template-columns:repeat(2,1fr)}.content-layout{grid-template-columns:minmax(0,1fr) 300px}.article-card{padding:36px}.page-hero h1{font-size:48px}.cta-box{padding:54px}.footer-inner{grid-template-columns:1.1fr 1.4fr}}
@media (max-width:420px){.container,.narrow{width:min(100% - 28px,1120px)}.hero-copy h1{font-size:32px}.section-title{font-size:26px}.page-hero h1{font-size:31px}.download-btn{width:100%}.visual-tag{font-size:12px;padding:7px 9px}.tag-b{top:64px}.tag-c{bottom:48px}.hero-visual{min-height:280px}.section{padding:58px 0}}