:root{--bg:#020c0e;--surface:#061518;--surface2:#0c2428;--border:#1a3840;--cyan:#22d3ee;--cyan-dark:#06b6d4;--cyan-glow:rgba(34,211,238,.16);--text:#e2fbff;--muted:#6badb8;--radius:12px}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{background:var(--bg);color:var(--text);font-family:'PingFang SC','Microsoft YaHei',sans-serif;line-height:1.7;font-size:16px}a{color:inherit;text-decoration:none}ul{list-style:none}
nav{position:sticky;top:0;z-index:100;background:rgba(2,12,14,.85);backdrop-filter:blur(16px);border-bottom:1px solid var(--border)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center;gap:10px;font-size:1.2rem;font-weight:700}
.logo-icon{width:36px;height:36px;background:linear-gradient(135deg,var(--cyan-dark),var(--cyan));border-radius:8px;display:flex;align-items:center;justify-content:center;font-size:18px}
.logo em{color:var(--cyan);font-style:normal}
.nav-links{display:flex;align-items:center;gap:26px;font-size:15px}
.nav-links a{color:var(--muted);transition:color .2s}.nav-links a:hover,.nav-links a.active{color:var(--text)}
.menu-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:4px}
.menu-toggle span{display:block;width:22px;height:2px;background:var(--text);border-radius:2px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:10px 22px;border-radius:var(--radius);font-size:15px;font-weight:600;cursor:pointer;transition:.2s;border:none;white-space:nowrap}
.btn-primary{background:linear-gradient(135deg,var(--cyan-dark),var(--cyan));color:#020c0e}
.btn-primary:hover{opacity:.88;transform:translateY(-1px)}
.btn-outline{background:transparent;color:var(--cyan);border:1.5px solid var(--cyan-dark)}
.btn-outline:hover{background:var(--cyan-glow)}
.btn-lg{padding:14px 36px;font-size:17px;border-radius:14px}
.nav-cta{padding:8px 18px;font-size:14px}
.container{max-width:1180px;margin:0 auto;padding:0 24px}
.hero{position:relative;padding:90px 0 70px;overflow:hidden;text-align:center}
.hero::before{content:'';position:absolute;top:-60px;left:50%;transform:translateX(-50%);width:800px;height:500px;background:radial-gradient(ellipse,rgba(6,182,212,.12) 0%,transparent 60%);pointer-events:none}
.hero-badge{display:inline-flex;align-items:center;gap:6px;background:rgba(34,211,238,.1);border:1px solid rgba(34,211,238,.25);color:var(--cyan);border-radius:999px;padding:5px 14px;font-size:13px;font-weight:600;margin-bottom:20px}
.hero h1{font-size:clamp(2rem,5vw,3.2rem);font-weight:800;line-height:1.2;margin-bottom:18px}
.hl{background:linear-gradient(135deg,var(--cyan-dark),var(--cyan));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero-sub{font-size:1.1rem;color:var(--muted);max-width:580px;margin:0 auto 34px}
.hero-btns{display:flex;gap:14px;justify-content:center;flex-wrap:wrap;margin-bottom:50px}
.hero-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;max-width:820px;margin:0 auto}
.stat-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:20px 16px;text-align:center}
.stat-num{font-size:2rem;font-weight:800;color:var(--cyan);line-height:1}
.stat-label{font-size:13px;color:var(--muted);margin-top:4px}
/* Subscription update guide — unique section */
.sub-update-section{padding:72px 0;background:var(--surface)}
.section-title{text-align:center;font-size:1.8rem;font-weight:700;margin-bottom:12px}
.section-sub{text-align:center;color:var(--muted);margin-bottom:44px;font-size:15px}
.sub-methods{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:940px;margin:0 auto 36px}
.sub-method-card{background:var(--surface2);border:1px solid var(--border);border-radius:14px;padding:26px 22px}
.sub-method-card.featured{border-color:var(--cyan-dark);box-shadow:0 0 20px var(--cyan-glow)}
.sub-method-icon{font-size:2rem;margin-bottom:12px}
.sub-method-card h3{font-size:1rem;font-weight:700;margin-bottom:10px}
.sub-method-steps{display:flex;flex-direction:column;gap:7px;margin-top:10px}
.sub-step{display:flex;align-items:flex-start;gap:10px;font-size:13.5px;color:var(--muted)}
.sub-step-num{min-width:22px;height:22px;background:var(--cyan-dark);color:#020c0e;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:700;flex-shrink:0;margin-top:1px}
.sub-update-tip{background:rgba(34,211,238,.07);border:1px solid rgba(34,211,238,.18);border-radius:10px;padding:16px 20px;max-width:700px;margin:0 auto;font-size:14px;color:var(--muted);text-align:center}
.sub-update-tip strong{color:var(--cyan)}
/* Features */
.section{padding:72px 0}
.feat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.feat-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:28px 24px}
.feat-icon{font-size:2rem;margin-bottom:14px}
.feat-card h3{font-size:1.05rem;font-weight:700;margin-bottom:8px}
.feat-card p{font-size:14px;color:var(--muted);line-height:1.7}
/* Plans — quarterly/annual */
.plan-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;max-width:900px;margin:0 auto}
.plan-card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:32px 28px;transition:transform .2s}
.plan-card.featured{border-color:var(--cyan-dark);box-shadow:0 0 32px var(--cyan-glow);transform:scale(1.03)}
.plan-badge{display:inline-block;background:var(--cyan-dark);color:#020c0e;font-size:12px;font-weight:700;padding:3px 10px;border-radius:999px;margin-bottom:14px}
.plan-name{font-size:1.2rem;font-weight:700;margin-bottom:4px}
.plan-desc{font-size:13px;color:var(--muted);margin-bottom:18px}
.plan-price{font-size:2.4rem;font-weight:800;color:var(--cyan);line-height:1;margin-bottom:4px}
.plan-price span{font-size:14px;color:var(--muted);font-weight:400}
.plan-origin{font-size:13px;color:var(--muted);text-decoration:line-through;margin-bottom:4px}
.plan-features{margin:18px 0 24px;display:flex;flex-direction:column;gap:9px}
.plan-features li{font-size:14px;color:var(--muted);padding-left:20px;position:relative}
.plan-features li::before{content:'✓';position:absolute;left:0;color:var(--cyan);font-weight:700}
.plan-features li.cross{color:#374151}.plan-features li.cross::before{content:'✗';color:#374151}
.steps-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:32px;max-width:860px;margin:0 auto}
.step{text-align:center}
.step-num{width:48px;height:48px;background:linear-gradient(135deg,var(--cyan-dark),var(--cyan));border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.2rem;font-weight:800;color:#020c0e;margin:0 auto 14px}
.step h3{font-size:1rem;font-weight:700;margin-bottom:8px}
.step p{font-size:14px;color:var(--muted)}
.platform-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px;max-width:800px;margin:0 auto}
.platform-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:20px 12px;text-align:center;font-size:13px}
.platform-card .p-icon{font-size:1.8rem;margin-bottom:8px}
.platform-card p{color:var(--muted);font-size:12px;margin-top:4px}
.review-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.review-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:24px}
.stars{color:#f59e0b;font-size:14px;margin-bottom:10px}
.review-card p{font-size:14px;color:var(--muted);line-height:1.75;margin-bottom:14px}
.reviewer{font-size:13px;font-weight:600;color:var(--cyan)}
.faq-list{max-width:780px;margin:0 auto;display:flex;flex-direction:column;gap:10px}
.faq-item{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden}
.faq-q{width:100%;display:flex;justify-content:space-between;align-items:center;padding:18px 22px;background:none;border:none;color:var(--text);font-size:15px;font-weight:600;cursor:pointer;text-align:left;gap:12px}
.faq-arrow{font-size:18px;color:var(--cyan);transition:transform .3s;flex-shrink:0}
.faq-item.open .faq-arrow{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .35s ease,padding .3s}
.faq-item.open .faq-a{max-height:400px;padding:0 22px 18px}
.faq-a p{font-size:14px;color:var(--muted);line-height:1.8}
.cta-section{padding:80px 0;background:linear-gradient(135deg,#061518,#0c2428,#061518);text-align:center;position:relative;overflow:hidden}
.cta-section::before{content:'';position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:600px;height:600px;background:radial-gradient(circle,rgba(6,182,212,.12) 0%,transparent 65%);pointer-events:none}
.cta-section h2{font-size:2rem;font-weight:800;margin-bottom:12px;position:relative}
.cta-section p{color:var(--muted);margin-bottom:32px;font-size:1.05rem;position:relative}
.cta-btns{display:flex;gap:14px;justify-content:center;flex-wrap:wrap;position:relative}
.page-hero{padding:52px 0 40px;background:var(--surface);border-bottom:1px solid var(--border)}
.page-hero h1{font-size:2rem;font-weight:800;margin-bottom:8px}
.page-hero p{color:var(--muted)}
.breadcrumb{font-size:13px;color:var(--muted);margin-bottom:12px;display:flex;align-items:center;gap:6px}
.breadcrumb a{color:var(--cyan)}
.dl-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-bottom:48px}
.dl-mobile{display:grid;grid-template-columns:repeat(2,1fr);gap:24px;margin-bottom:56px;max-width:620px;margin-left:auto;margin-right:auto}
.dl-card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:30px 24px;text-align:center}
.dl-icon{font-size:2.5rem;margin-bottom:12px}
.dl-card h3{font-size:1.1rem;font-weight:700;margin-bottom:8px}
.dl-card p{font-size:14px;color:var(--muted);margin-bottom:18px;line-height:1.6}
.dl-card .btn{width:100%;margin-bottom:8px}
.dl-ver{font-size:12px;color:var(--muted);margin-top:8px}
.tut-content{max-width:820px;margin:0 auto}
.tut-sec{margin-bottom:48px}
.tut-sec h2{font-size:1.35rem;font-weight:700;margin-bottom:14px;padding-bottom:10px;border-bottom:1px solid var(--border)}
.tut-sec h3{font-size:1.05rem;font-weight:700;margin:20px 0 8px}
.tut-sec p{font-size:14.5px;color:var(--muted);margin-bottom:10px;line-height:1.8}
.tut-sec ul,.tut-sec ol{padding-left:18px;display:flex;flex-direction:column;gap:8px}
.tut-sec ul{list-style:disc}.tut-sec ol{list-style:decimal}
.tut-sec li{font-size:14.5px;color:var(--muted);line-height:1.7}
.tip-box{background:rgba(34,211,238,.07);border-left:3px solid var(--cyan-dark);border-radius:0 8px 8px 0;padding:12px 16px;font-size:14px;color:var(--muted);margin:12px 0}
footer{background:var(--surface);border-top:1px solid var(--border);padding:48px 0 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;margin-bottom:36px}
.footer-brand p{font-size:13px;color:var(--muted);margin-top:10px;line-height:1.7}
.footer-col h4{font-size:14px;font-weight:700;margin-bottom:12px}
.footer-col ul{display:flex;flex-direction:column;gap:8px}
.footer-col li a{font-size:13px;color:var(--muted);transition:color .2s}
.footer-col li a:hover{color:var(--cyan)}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;padding-top:24px;border-top:1px solid var(--border);font-size:13px;color:var(--muted)}
.footer-icp a{color:var(--muted)}.footer-icp a:hover{color:var(--cyan)}
@media(max-width:900px){.feat-grid{grid-template-columns:1fr 1fr}.plan-grid{grid-template-columns:1fr}.plan-card.featured{transform:none}.sub-methods{grid-template-columns:1fr}.steps-grid{grid-template-columns:1fr;gap:24px}.review-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr 1fr}.dl-grid{grid-template-columns:1fr}.dl-mobile{grid-template-columns:1fr;max-width:400px}}
@media(max-width:680px){.hero-stats{grid-template-columns:repeat(2,1fr)}.feat-grid{grid-template-columns:1fr}.platform-grid{grid-template-columns:repeat(3,1fr)}.nav-links{display:none;position:absolute;top:64px;left:0;right:0;background:var(--bg);padding:20px 24px 24px;flex-direction:column;align-items:flex-start;gap:18px;border-bottom:1px solid var(--border)}.nav-links.open{display:flex}.menu-toggle{display:flex}.footer-grid{grid-template-columns:1fr}.footer-bottom{flex-direction:column;gap:8px;text-align:center}}