/* ========== Design Tokens ========== */
:root{
  --primary-500:#4F46E5;
  --primary-600:#4338CA;
  --primary-grad:linear-gradient(135deg,#22D3EE 0%,#4F46E5 100%);
  --accent:#22D3EE;
  --accent-soft:rgba(34,211,238,.12);
  --accent-warm:#FF6B6B;
  --bg-dark:#080D1C;
  --bg-dark-2:#0C1328;
  --bg-light:#F6F8FC;
  --text-primary:#141A2B;
  --text-secondary:#6A7288;
  --text-on-dark:#FFFFFF;
  --text-on-dark-sub:#A9B4D0;
  --success:#10B981;
  --warning:#F59E0B;
  --error:#EF4444;
  --radius-sm:4px;
  --radius-md:8px;
  --radius-lg:16px;
  --radius-xl:24px;
  --shadow-sm:0 2px 8px rgba(14,22,48,.06);
  --shadow-md:0 8px 24px rgba(14,22,48,.08);
  --shadow-lg:0 16px 48px rgba(14,22,48,.12);
  --shadow-glow:0 0 32px rgba(79,70,229,.35);
}
*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  font-family:"Inter","PingFang SC","Microsoft YaHei",-apple-system,sans-serif;
  color:var(--text-primary);
  background:var(--bg-light);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
a{text-decoration:none;color:inherit;}
img{max-width:100%;display:block;}
.container{max-width:1200px;margin:0 auto;padding:0 24px;}
.section{padding:120px 0;}
.section-title{
  font-size:40px;font-weight:700;text-align:center;
  letter-spacing:-.5px;margin-bottom:16px;
}
.section-sub{
  font-size:17px;color:var(--text-secondary);
  text-align:center;max-width:720px;margin:0 auto 64px;line-height:1.8;
}

/* ========== Buttons ========== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:14px 28px;border-radius:var(--radius-md);
  font-size:15px;font-weight:600;cursor:pointer;border:none;
  transition:all .2s ease;white-space:nowrap;
}
.btn-primary{
  background:var(--primary-grad);color:#fff;
  box-shadow:0 4px 16px rgba(79,70,229,.35);
}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 24px rgba(79,70,229,.5);}
.btn-secondary{
  background:transparent;color:#fff;
  border:1.5px solid rgba(255,255,255,.35);
}
.btn-secondary:hover{background:rgba(255,255,255,.1);border-color:#fff;}
.btn-outline{
  background:#fff;color:var(--primary-500);
  border:1.5px solid var(--primary-500);
}
.btn-outline:hover{background:var(--primary-500);color:#fff;}
.btn-sm{padding:10px 20px;font-size:14px;}
.btn-lg{padding:18px 36px;font-size:17px;}

/* ========== Header ========== */
.header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  padding:16px 0;transition:all .3s ease;
}
.header.scrolled{
  background:rgba(8,13,28,.92);
  backdrop-filter:blur(16px);
  box-shadow:0 4px 24px rgba(0,0,0,.3);
  padding:12px 0;
}
.header-inner{
  display:flex;align-items:center;justify-content:space-between;gap:32px;
}
.logo{
  display:flex;align-items:center;gap:10px;
  font-size:22px;font-weight:700;color:#fff;letter-spacing:-.3px;
}
.logo-img{height:36px;width:auto;display:block;}
.logo-text{font-size:22px;font-weight:700;color:#fff;letter-spacing:-.3px;}
.nav{display:flex;gap:32px;}
.nav a{
  color:var(--text-on-dark-sub);font-size:15px;font-weight:500;
  transition:color .2s;
}
.nav a:hover{color:#fff;}
.nav a.current{color:#fff;position:relative;}
.nav a.current::after{
  content:"";position:absolute;left:0;right:0;bottom:-6px;height:2px;
  background:var(--primary-grad);border-radius:2px;
}
.header-actions{display:flex;align-items:center;gap:16px;}
.lang-switch{
  display:flex;align-items:center;gap:6px;
  color:var(--text-on-dark-sub);font-size:14px;cursor:pointer;
}
.login-link{color:var(--text-on-dark-sub);font-size:15px;font-weight:500;}
.login-link:hover{color:#fff;}
.hamburger{
  display:none;background:none;border:none;color:#fff;font-size:24px;cursor:pointer;
}
.mobile-menu{
  display:none;position:fixed;top:64px;left:0;right:0;
  background:rgba(8,13,28,.98);backdrop-filter:blur(20px);
  padding:24px;flex-direction:column;gap:20px;z-index:99;
  border-bottom:1px solid rgba(255,255,255,.08);
}
.mobile-menu.open{display:flex;}
.mobile-menu a{color:#fff;font-size:16px;padding:8px 0;}

/* ========== Hero ========== */
.hero{
  position:relative;min-height:100vh;
  background:var(--bg-dark);
  display:flex;align-items:center;
  padding:140px 0 80px;overflow:hidden;
}
.hero::before{
  content:"";position:absolute;inset:0;
  background:
    radial-gradient(circle at 18% 28%,rgba(79,70,229,.32),transparent 52%),
    radial-gradient(circle at 82% 72%,rgba(34,211,238,.20),transparent 52%);
}
.hero::after{
  content:"";position:absolute;inset:0;
  background-image:
    radial-gradient(circle,rgba(255,255,255,.06) 1px,transparent 1px);
  background-size:32px 32px;
  opacity:.5;
}
.hero-inner{
  position:relative;z-index:2;
  display:grid;grid-template-columns:1.1fr 1fr;
  gap:64px;align-items:center;width:100%;
}
.hero-text{color:#fff;}
.hero h1{
  font-size:56px;line-height:1.15;font-weight:700;
  letter-spacing:-1.5px;margin-bottom:24px;
}
.hero h1 .grad{
  background:var(--primary-grad);
  -webkit-background-clip:text;background-clip:text;
  -webkit-text-fill-color:transparent;
}
.hero-sub{
  font-size:17px;color:var(--text-on-dark-sub);
  max-width:600px;margin-bottom:36px;line-height:1.85;
}
.hero-cta{display:flex;gap:16px;flex-wrap:wrap;margin-bottom:28px;}
.hero-trust{
  display:flex;gap:24px;flex-wrap:wrap;
  font-size:13px;color:var(--text-on-dark-sub);
}
.hero-trust span{display:flex;align-items:center;gap:6px;}
.hero-trust .check{color:var(--accent);font-weight:700;}

/* Hero visual */
.hero-visual{position:relative;display:flex;justify-content:center;}
.hero-image{
  width:100%;max-width:520px;
  border-radius:var(--radius-xl);
  box-shadow:0 24px 64px rgba(0,0,0,.5),var(--shadow-glow);
  transform:perspective(1000px) rotateY(-6deg) rotateX(3deg);
}
.float-tag{
  position:absolute;padding:10px 16px;border-radius:var(--radius-md);
  background:rgba(255,255,255,.1);backdrop-filter:blur(12px);
  border:1px solid rgba(255,255,255,.2);
  font-size:12px;color:#fff;font-weight:500;
  display:flex;align-items:center;gap:6px;
  box-shadow:var(--shadow-md);
}
.float-tag.t1{top:-16px;left:-24px;animation:float 4s ease-in-out infinite;}
.float-tag.t2{bottom:24px;right:-32px;animation:float 4s ease-in-out infinite .5s;}
@keyframes float{0%,100%{transform:translateY(0);}50%{transform:translateY(-8px);}}

/* ========== Trust Bar ========== */
.trust-bar{
  background:#fff;padding:32px 0;
  border-bottom:1px solid #E9EEF6;
}
.trust-inner{
  display:flex;align-items:center;justify-content:space-around;
  flex-wrap:wrap;gap:24px;
}
.trust-item{
  display:flex;align-items:center;gap:10px;
  font-size:14px;color:var(--text-secondary);font-weight:500;
}
.trust-item .num{
  font-size:20px;font-weight:700;color:var(--primary-500);
}

/* ========== Speed Meter (页面特色) ========== */
.meter{background:#fff;padding:96px 0;}
.meter-grid{
  display:grid;grid-template-columns:repeat(4,1fr);gap:20px;
}
.meter-card{
  background:var(--bg-light);border:1px solid #E9EEF6;
  border-radius:var(--radius-lg);padding:28px 24px;
  text-align:center;transition:all .25s ease;
}
.meter-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);border-color:rgba(79,70,229,.3);}
.meter-value{
  font-size:40px;font-weight:700;letter-spacing:-1px;
  background:var(--primary-grad);
  -webkit-background-clip:text;background-clip:text;
  -webkit-text-fill-color:transparent;
}
.meter-label{font-size:14px;font-weight:600;margin-top:8px;}
.meter-desc{font-size:12px;color:var(--text-secondary);margin-top:6px;line-height:1.7;}
.meter-bar{
  height:6px;border-radius:999px;background:#E5EAF3;
  margin-top:16px;overflow:hidden;
}
.meter-bar i{
  display:block;height:100%;border-radius:999px;
  background:var(--primary-grad);width:0;
  transition:width 1.2s cubic-bezier(.4,0,.2,1);
}
.meter-card.visible .meter-bar i{width:var(--w,80%);}

/* ========== Features ========== */
.features{background:#fff;}
.features-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:24px;
}
.feature-card{
  background:#fff;border:1px solid #E9EEF6;
  border-radius:var(--radius-lg);padding:32px;
  transition:all .25s ease;cursor:default;
}
.feature-card:hover{
  transform:translateY(-4px);
  box-shadow:var(--shadow-md);
  border-color:rgba(79,70,229,.3);
}
.feature-icon{
  width:56px;height:56px;border-radius:14px;
  background:var(--primary-grad);
  display:flex;align-items:center;justify-content:center;
  font-size:26px;margin-bottom:20px;
  box-shadow:0 6px 16px rgba(79,70,229,.3);
}
.feature-card h3{font-size:19px;font-weight:700;margin-bottom:10px;}
.feature-card p{font-size:14px;color:var(--text-secondary);line-height:1.85;}

/* ========== Timeline (页面特色) ========== */
.timeline{background:var(--bg-light);}
.tl-wrap{
  background:var(--bg-dark);border-radius:var(--radius-xl);
  padding:64px 56px;position:relative;overflow:hidden;
}
.tl-wrap::before{
  content:"";position:absolute;inset:0;
  background:radial-gradient(circle at 20% 30%,rgba(79,70,229,.35),transparent 58%),
             radial-gradient(circle at 80% 70%,rgba(34,211,238,.22),transparent 58%);
}
.tl-inner{position:relative;z-index:2;}
.tl-head{text-align:center;color:#fff;margin-bottom:56px;}
.tl-head h3{font-size:30px;font-weight:700;letter-spacing:-.5px;margin-bottom:12px;}
.tl-head p{font-size:15px;color:var(--text-on-dark-sub);max-width:620px;margin:0 auto;line-height:1.8;}
.tl-track{
  position:relative;display:grid;
  grid-template-columns:repeat(5,1fr);gap:16px;
}
.tl-track::before{
  content:"";position:absolute;top:22px;left:6%;right:6%;height:2px;
  background:linear-gradient(90deg,rgba(34,211,238,.6),rgba(79,70,229,.6));
}
.tl-node{position:relative;text-align:center;color:#fff;}
.tl-dot{
  width:44px;height:44px;border-radius:50%;
  background:var(--primary-grad);
  display:flex;align-items:center;justify-content:center;
  margin:0 auto 16px;font-size:18px;font-weight:700;
  box-shadow:0 0 0 6px rgba(34,211,238,.12);
  position:relative;z-index:2;
}
.tl-time{
  font-size:13px;font-weight:700;color:var(--accent);
  letter-spacing:.5px;margin-bottom:6px;
}
.tl-node h4{font-size:15px;font-weight:600;margin-bottom:6px;}
.tl-node p{font-size:12px;color:var(--text-on-dark-sub);line-height:1.7;padding:0 4px;}

/* ========== Compare (页面特色) ========== */
.compare{background:#fff;}
.compare-box{
  max-width:900px;margin:0 auto;
  background:var(--bg-light);border-radius:var(--radius-xl);
  padding:48px;border:1px solid #E9EEF6;
}
.compare-row{margin-bottom:28px;}
.compare-row:last-child{margin-bottom:0;}
.compare-label{
  display:flex;justify-content:space-between;
  font-size:14px;font-weight:600;margin-bottom:10px;
}
.compare-label .val{color:var(--primary-500);}
.compare-track{
  height:14px;border-radius:999px;background:#E5EAF3;overflow:hidden;
}
.compare-track i{
  display:block;height:100%;border-radius:999px;
  width:0;transition:width 1.2s cubic-bezier(.4,0,.2,1);
}
.compare-track.slow i{background:linear-gradient(90deg,#CBD5E1,#94A3B8);}
.compare-track.fast i{background:var(--primary-grad);}
.compare-row.visible .compare-track i{width:var(--w,60%);}
.compare-note{
  text-align:center;font-size:13px;color:var(--text-secondary);
  margin-top:28px;line-height:1.8;
}

/* ========== Use Cases ========== */
.use-cases{background:var(--bg-light);}
.tabs{
  display:flex;justify-content:center;gap:8px;
  margin-bottom:48px;flex-wrap:wrap;
}
.tab{
  padding:10px 22px;border-radius:999px;
  background:#fff;border:1px solid #E2E8F2;
  font-size:14px;font-weight:500;color:var(--text-secondary);
  cursor:pointer;transition:all .2s;
}
.tab.active{
  background:var(--primary-grad);color:#fff;border-color:transparent;
  box-shadow:0 4px 12px rgba(79,70,229,.3);
}
.tab-panel{display:none;}
.tab-panel.active{display:block;animation:fadeIn .4s ease;}
@keyframes fadeIn{from{opacity:0;transform:translateY(10px);}to{opacity:1;transform:translateY(0);}}
.panel-inner{
  background:#fff;border-radius:var(--radius-xl);
  padding:48px;display:grid;grid-template-columns:1fr 1fr;
  gap:48px;align-items:center;box-shadow:var(--shadow-sm);
}
.panel-inner h3{font-size:28px;font-weight:700;margin-bottom:16px;}
.panel-inner p{font-size:15px;color:var(--text-secondary);margin-bottom:20px;line-height:1.9;}
.panel-list{list-style:none;}
.panel-list li{
  display:flex;align-items:center;gap:10px;
  font-size:14px;color:var(--text-primary);margin-bottom:10px;
}
.panel-list .check{color:var(--success);font-weight:700;}
.panel-visual{
  height:240px;border-radius:var(--radius-lg);
  background:var(--primary-grad);
  display:flex;align-items:center;justify-content:center;
  font-size:72px;color:#fff;
  box-shadow:var(--shadow-md);
}

/* ========== Scenarios Grid (页面特色) ========== */
.scenarios{background:#fff;}
.scenario-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:24px;
}
.scenario-card{
  background:var(--bg-light);border:1px solid #E9EEF6;
  border-radius:var(--radius-lg);padding:32px;
  transition:all .25s ease;
}
.scenario-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);border-color:rgba(79,70,229,.3);}
.scenario-top{
  display:flex;align-items:center;gap:12px;margin-bottom:16px;
}
.scenario-emoji{font-size:28px;}
.scenario-card h3{font-size:18px;font-weight:700;}
.scenario-card p{font-size:14px;color:var(--text-secondary);line-height:1.85;margin-bottom:14px;}
.scenario-tag{
  display:inline-block;font-size:12px;font-weight:700;
  color:var(--primary-500);background:rgba(79,70,229,.08);
  padding:4px 12px;border-radius:999px;
}

/* ========== Testimonials ========== */
.testimonials{background:var(--bg-light);}
.testi-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:24px;
}
.testi-card{
  background:#fff;border-radius:var(--radius-lg);
  padding:28px;box-shadow:var(--shadow-sm);
}
.testi-stars{color:#FBBF24;font-size:14px;margin-bottom:12px;}
.testi-text{
  font-size:14px;color:var(--text-primary);
  line-height:1.9;margin-bottom:20px;
}
.testi-user{display:flex;align-items:center;gap:12px;}
.testi-avatar{
  width:40px;height:40px;border-radius:50%;
  background:var(--primary-grad);
  display:flex;align-items:center;justify-content:center;
  color:#fff;font-weight:700;font-size:15px;
}
.testi-name{font-size:14px;font-weight:600;}
.testi-role{font-size:12px;color:var(--text-secondary);}

/* ========== FAQ ========== */
.faq{background:#fff;}
.faq-list{max-width:840px;margin:0 auto;}
.faq-item{border-bottom:1px solid #E9EEF6;}
.faq-q{
  display:flex;justify-content:space-between;align-items:center;
  padding:22px 0;font-size:16px;font-weight:600;
  cursor:pointer;transition:color .2s;
}
.faq-q:hover{color:var(--primary-500);}
.faq-q .icon{
  font-size:20px;color:var(--primary-500);
  transition:transform .3s;flex-shrink:0;margin-left:16px;
}
.faq-item.open .faq-q .icon{transform:rotate(45deg);}
.faq-a{
  max-height:0;overflow:hidden;
  transition:max-height .3s ease,padding .3s ease;
  font-size:14px;color:var(--text-secondary);line-height:1.9;
}
.faq-item.open .faq-a{max-height:320px;padding-bottom:22px;}

/* ========== Bottom CTA ========== */
.bottom-cta{
  background:var(--bg-dark);position:relative;overflow:hidden;
  padding:96px 0;
}
.bottom-cta::before{
  content:"";position:absolute;inset:0;
  background:radial-gradient(circle at 50% 50%,rgba(79,70,229,.38),transparent 62%);
}
.bottom-cta-inner{position:relative;z-index:2;text-align:center;color:#fff;}
.bottom-cta h2{
  font-size:40px;font-weight:700;letter-spacing:-1px;margin-bottom:16px;
}
.bottom-cta p{
  font-size:17px;color:var(--text-on-dark-sub);
  max-width:640px;margin:0 auto 36px;line-height:1.8;
}
.bottom-cta .hero-cta{justify-content:center;}
.bottom-cta .trust{
  margin-top:24px;font-size:13px;color:var(--text-on-dark-sub);
  display:flex;justify-content:center;gap:20px;flex-wrap:wrap;
}

/* ========== Footer ========== */
.footer{
  background:#04060F;color:var(--text-on-dark-sub);
  padding:64px 0 32px;
}
.footer-grid{
  display:grid;grid-template-columns:2fr 1fr 1fr 1fr 1.5fr;
  gap:40px;margin-bottom:48px;
}
.footer-brand .logo{margin-bottom:16px;}
.footer-brand p{font-size:13px;line-height:1.9;max-width:300px;}
.footer-col h4{
  color:#fff;font-size:14px;font-weight:600;margin-bottom:18px;
}
.footer-col a{
  display:block;font-size:13px;margin-bottom:10px;
  transition:color .2s;
}
.footer-col a:hover{color:#fff;}
.footer-subscribe input{
  width:100%;padding:12px 16px;border-radius:var(--radius-md);
  border:1px solid rgba(255,255,255,.15);
  background:rgba(255,255,255,.05);color:#fff;
  font-size:13px;margin-bottom:10px;outline:none;
}
.footer-subscribe input:focus{border-color:var(--primary-500);}
.footer-subscribe .btn{width:100%;}
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.08);
  padding-top:24px;display:flex;justify-content:space-between;
  align-items:center;flex-wrap:wrap;gap:16px;font-size:12px;
}
.footer-social{display:flex;gap:16px;}
.footer-social a{
  width:32px;height:32px;border-radius:50%;
  background:rgba(255,255,255,.08);
  display:flex;align-items:center;justify-content:center;
  transition:background .2s;
}
.footer-social a:hover{background:var(--primary-500);color:#fff;}

/* ========== Animations ========== */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .6s ease,transform .6s ease;}
.reveal.visible{opacity:1;transform:translateY(0);}

/* ========== Responsive ========== */
@media(max-width:1024px){
  .hero-inner{grid-template-columns:1fr;gap:48px;}
  .hero h1{font-size:44px;}
  .hero-visual{max-width:520px;margin:0 auto;}
  .features-grid{grid-template-columns:repeat(2,1fr);}
  .meter-grid{grid-template-columns:repeat(2,1fr);}
  .scenario-grid{grid-template-columns:repeat(2,1fr);}
  .testi-grid{grid-template-columns:1fr;}
  .footer-grid{grid-template-columns:1fr 1fr;}
  .tl-track{grid-template-columns:repeat(3,1fr);gap:32px;}
  .tl-track::before{display:none;}
}
@media(max-width:768px){
  .nav,.header-actions .login-link,.lang-switch{display:none;}
  .hamburger{display:block;}
  .section{padding:64px 0;}
  .section-title{font-size:28px;}
  .section-sub{font-size:15px;margin-bottom:40px;}
  .hero h1{font-size:32px;letter-spacing:-.5px;}
  .hero-sub{font-size:15px;}
  .hero-cta{flex-direction:column;}
  .hero-cta .btn{width:100%;}
  .features-grid{grid-template-columns:1fr;}
  .meter-grid{grid-template-columns:1fr;}
  .scenario-grid{grid-template-columns:1fr;}
  .panel-inner{grid-template-columns:1fr;padding:32px;}
  .panel-visual{height:160px;font-size:56px;}
  .tl-wrap{padding:40px 24px;}
  .tl-track{grid-template-columns:1fr;gap:28px;}
  .compare-box{padding:28px;}
  .bottom-cta h2{font-size:28px;}
  .footer-grid{grid-template-columns:1fr;}
  .footer-bottom{flex-direction:column;text-align:center;}
  .float-tag{display:none;}
  .logo-img{height:30px;}
  .logo-text{font-size:18px;}
}