:root{
  --navy:#0B1220; --navy-2:#111A2E; --navy-3:#1A2540;
  --blue:#2563EB; --blue-2:#3B82F6; --blue-3:#60A5FA; --blue-dk:#1D4ED8;
  --ink:#0B1220; --ink-2:#334155; --ink-3:#64748B;
  --line:#E2E8F0; --bg:#FFFFFF; --bg-2:#F5F8FF;
  --radius:16px; --shadow:0 1px 2px rgba(15,23,42,.06),0 8px 24px rgba(15,23,42,.06);
  --font:"Be Vietnam Pro",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:80px;-webkit-text-size-adjust:100%}
body{margin:0;font-family:var(--font);color:var(--ink);background:var(--bg);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
img,svg{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{line-height:1.2;margin:0 0 .5em;letter-spacing:-.02em}
h2{font-size:clamp(1.75rem,3.2vw,2.5rem);font-weight:700}
h3{font-size:1.125rem;font-weight:600}
p{margin:0 0 1em}
.container{width:100%;max-width:1200px;margin:0 auto;padding:0 24px}
.container--narrow{max-width:820px}
.skip{position:absolute;left:-9999px}.skip:focus{left:16px;top:16px;z-index:100;background:#fff;padding:8px 12px;border-radius:8px}
:focus-visible{outline:2px solid var(--blue-2);outline-offset:3px;border-radius:6px}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font-weight:600;border-radius:12px;padding:12px 20px;font-size:.95rem;border:1px solid transparent;transition:transform .15s,box-shadow .2s,background .2s,color .2s;cursor:pointer;white-space:nowrap}
.btn:hover{transform:translateY(-1px)}
.btn--sm{padding:8px 14px;font-size:.875rem;border-radius:10px}
.btn--lg{padding:14px 26px;font-size:1rem}
.btn--block{width:100%}
.btn--primary{background:linear-gradient(135deg,var(--blue-2),var(--blue-dk));color:#fff;box-shadow:0 6px 20px rgba(37,99,235,.35)}
.btn--primary:hover{box-shadow:0 10px 28px rgba(37,99,235,.45)}
.btn--ghost{color:#fff;border-color:rgba(255,255,255,.22);background:rgba(255,255,255,.04)}
.btn--ghost:hover{background:rgba(255,255,255,.1)}
.btn--outline{border-color:var(--line);color:var(--ink);background:#fff}
.btn--outline:hover{border-color:var(--blue-2);color:var(--blue)}

.eyebrow{display:inline-flex;align-items:center;gap:8px;font-size:.8rem;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--blue);margin-bottom:14px}
.eyebrow--dark{color:var(--blue-3)}
.eyebrow .dot{width:6px;height:6px;border-radius:50%;background:#34D399;box-shadow:0 0 0 4px rgba(52,211,153,.18)}
.grad{background:linear-gradient(90deg,#60A5FA,#93C5FD 40%,#A78BFA);-webkit-background-clip:text;background-clip:text;color:transparent}

/* channel icon via mask */
.ci{display:inline-block;width:18px;height:18px;flex:none;background:var(--c,#fff);-webkit-mask:var(--i) center/contain no-repeat;mask:var(--i) center/contain no-repeat}
.ci--svg{background:none;-webkit-mask:none;mask:none;color:var(--c)}
.ci--svg svg{width:100%;height:100%}
.ci--xs{width:14px;height:14px}
.ci--lg{width:34px;height:34px}

/* ============ NAV ============ */
.nav{position:fixed;inset:0 0 auto;z-index:50;transition:background .25s,box-shadow .25s,border-color .25s;border-bottom:1px solid transparent}
.nav__inner{display:flex;align-items:center;gap:32px;height:72px}
.nav__brand{display:flex;align-items:center}
.nav__brand .logo{height:34px;width:auto}
.logo--dark{display:none}
.nav__links{display:flex;gap:28px;margin-left:auto}
.nav__links a{color:rgba(255,255,255,.78);font-size:.925rem;font-weight:500;transition:color .2s}
.nav__links a:hover{color:#fff}
.nav__actions{display:flex;align-items:center;gap:12px}
.lang{display:flex;padding:3px;border-radius:999px;border:1px solid rgba(255,255,255,.2);background:transparent;cursor:pointer;font:inherit;font-size:.75rem;font-weight:600}
.lang span{padding:4px 9px;border-radius:999px;color:rgba(255,255,255,.65)}
html[lang=vi] .lang [data-lang=vi],html[lang=en] .lang [data-lang=en]{background:#fff;color:var(--navy)}
.nav__burger{display:none;width:40px;height:40px;border:0;background:transparent;cursor:pointer;flex-direction:column;justify-content:center;gap:6px;padding:0 9px}
.nav__burger span{height:2px;background:#fff;border-radius:2px;transition:transform .25s}
.nav.is-scrolled{background:rgba(255,255,255,.88);backdrop-filter:saturate(180%) blur(14px);-webkit-backdrop-filter:saturate(180%) blur(14px);border-color:var(--line)}
.nav.is-scrolled .logo--light{display:none}.nav.is-scrolled .logo--dark{display:block}
.nav.is-scrolled .nav__links a{color:var(--ink-2)}.nav.is-scrolled .nav__links a:hover{color:var(--blue)}
.nav.is-scrolled .lang{border-color:var(--line)}.nav.is-scrolled .lang span{color:var(--ink-3)}
html[lang=vi] .nav.is-scrolled .lang [data-lang=vi],html[lang=en] .nav.is-scrolled .lang [data-lang=en]{background:var(--navy);color:#fff}
.nav.is-scrolled .nav__burger span{background:var(--ink)}

/* ============ HERO ============ */
.hero{position:relative;background:var(--navy);color:#fff;padding:150px 0 110px;overflow:hidden}
.hero__glow{position:absolute;width:900px;height:900px;right:-250px;top:-380px;background:radial-gradient(circle,rgba(37,99,235,.45),rgba(11,18,32,0) 65%);pointer-events:none}
.hero__grid{position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px);background-size:56px 56px;mask-image:radial-gradient(ellipse at 70% 30%,#000 10%,transparent 70%);-webkit-mask-image:radial-gradient(ellipse at 70% 30%,#000 10%,transparent 70%)}
.hero__inner{position:relative;display:grid;grid-template-columns:1.02fr 1fr;gap:56px;align-items:center}
.hero h1{font-size:clamp(2.25rem,4.6vw,3.6rem);font-weight:800;letter-spacing:-.03em;margin-bottom:20px}
.lead{font-size:1.125rem;color:rgba(226,232,240,.8);max-width:560px;margin-bottom:32px}
.hero__cta{display:flex;flex-wrap:wrap;gap:12px;margin-bottom:36px}
.hero__channels{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:10px}
.hero__channels li{display:flex;align-items:center;gap:8px;padding:7px 12px;border-radius:999px;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.1);font-size:.85rem;color:rgba(255,255,255,.85)}

/* product mock */
.mock{background:#fff;color:var(--ink);border-radius:18px;box-shadow:0 30px 80px rgba(0,0,0,.45),0 0 0 1px rgba(255,255,255,.08);overflow:hidden;transform:perspective(1600px) rotateY(-6deg) rotateX(2deg);transition:transform .6s}
.mock:hover{transform:none}
.mock__bar{display:flex;align-items:center;gap:6px;padding:11px 14px;background:#F1F5F9;border-bottom:1px solid var(--line)}
.mock__bar i{width:10px;height:10px;border-radius:50%;background:#CBD5E1}
.mock__bar i:nth-child(1){background:#F87171}.mock__bar i:nth-child(2){background:#FBBF24}.mock__bar i:nth-child(3){background:#34D399}
.mock__bar span{margin-left:12px;font-size:.72rem;color:var(--ink-3);background:#fff;padding:3px 10px;border-radius:6px}
.mock__body{display:grid;grid-template-columns:200px 1fr;min-height:360px}
.mock__list{border-right:1px solid var(--line);padding:8px}
.mock__item{display:flex;align-items:center;gap:10px;padding:10px 8px;border-radius:10px;font-size:.78rem}
.mock__item>div{flex:1;min-width:0}
.mock__item b{display:block;font-weight:600}
.mock__item small{display:block;color:var(--ink-3);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.mock__item.is-active{background:#EFF6FF}
.av{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;flex:none;font-size:.68rem;font-weight:700;color:#fff;background:var(--a)}
.mock__chat{padding:18px;display:flex;flex-direction:column;gap:10px;background:#FAFBFF}
.msg{max-width:80%;padding:9px 13px;border-radius:14px;font-size:.8rem;line-height:1.45}
.msg--in{background:#fff;border:1px solid var(--line);border-bottom-left-radius:4px}
.msg--out{align-self:flex-end;background:var(--blue);color:#fff;border-bottom-right-radius:4px}
.ai-card{margin-top:auto;border-radius:14px;padding:13px 14px;background:linear-gradient(135deg,#EEF4FF,#F5F0FF);border:1px solid #DBE5FF;font-size:.78rem}
.ai-card p{margin:6px 0 10px}
.ai-card__head{display:flex;align-items:center;gap:6px;font-weight:700;color:var(--blue-dk);font-size:.75rem;text-transform:uppercase;letter-spacing:.06em}
.spark{color:#7C3AED}
.ai-card__tags{display:flex;flex-wrap:wrap;gap:6px}
.tag{font-size:.7rem;font-weight:600;padding:3px 9px;border-radius:999px;background:#fff;border:1px solid var(--line);color:var(--ink-2)}
.tag--warn{background:#FEF2F2;border-color:#FECACA;color:#B91C1C}
.tag--ok{background:#ECFDF5;border-color:#A7F3D0;color:#047857}

/* ============ STRIP ============ */
.strip{border-bottom:1px solid var(--line);padding:34px 0}
.strip__inner{display:flex;align-items:center;justify-content:space-between;gap:24px;flex-wrap:wrap}
.strip p{margin:0;color:var(--ink-3);font-weight:500;max-width:360px}
.strip__logos{display:flex;align-items:center;gap:30px;flex-wrap:wrap}
.strip__voice{font-weight:700;color:var(--ink-3);letter-spacing:.04em;font-size:.95rem;padding:6px 12px;border:1.5px solid var(--line);border-radius:10px}

/* ============ SECTIONS ============ */
.section{padding:110px 0}
.section--tint{background:var(--bg-2)}
.section--dark{background:var(--navy);color:#fff}
.section__head{text-align:center;max-width:720px;margin:0 auto 60px}
.section__head p{color:var(--ink-3);font-size:1.075rem}
.grid{display:grid;gap:24px}
.grid--3{grid-template-columns:repeat(3,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px;transition:transform .2s,box-shadow .2s,border-color .2s}
.card:hover{transform:translateY(-3px);box-shadow:var(--shadow);border-color:#C7D7FE}
.card p{color:var(--ink-3);margin:0;font-size:.95rem}
.card__icon{width:48px;height:48px;border-radius:12px;display:grid;place-items:center;background:linear-gradient(135deg,#EFF6FF,#DBEAFE);margin-bottom:18px}
.card__icon svg{width:24px;height:24px;fill:none;stroke:var(--blue);stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.card--int p{margin-bottom:16px}
.mini{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:8px}
.mini li{font-size:.78rem;font-weight:600;color:var(--blue-dk);background:#EFF6FF;padding:4px 10px;border-radius:999px}

.split{display:grid;grid-template-columns:1fr 1fr;gap:72px;align-items:center}
.split--rev .split__copy{order:2}
.lead-sm{font-size:1.075rem;color:var(--ink-3);margin-bottom:28px}
.section--dark .lead-sm{color:rgba(226,232,240,.75)}
.checks{list-style:none;padding:0;margin:0;display:grid;gap:16px}
.checks li{position:relative;padding-left:36px}
.checks li::before{content:"";position:absolute;left:0;top:2px;width:22px;height:22px;border-radius:50%;background:var(--blue) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12l5 5 9-10'/%3E%3C/svg%3E") center/13px no-repeat}
.checks b{display:block;font-weight:600}
.checks span{color:var(--ink-3);font-size:.95rem}

/* AI flow */
.flow{background:#fff;border:1px solid var(--line);border-radius:22px;padding:32px;box-shadow:var(--shadow);display:flex;flex-direction:column;align-items:center}
.flow__step{display:flex;align-items:center;gap:14px;background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 18px;width:100%;max-width:340px}
.flow__step b{display:block;font-size:.95rem}
.flow__step small{color:var(--ink-3)}
.flow__n{width:38px;height:38px;border-radius:10px;display:grid;place-items:center;flex:none;font-weight:700;background:#F1F5F9;color:var(--ink-2)}
.flow__step--ai{border-color:transparent;background:linear-gradient(135deg,var(--blue-2),#6D28D9);color:#fff;box-shadow:0 12px 30px rgba(37,99,235,.35)}
.flow__step--ai small{color:rgba(255,255,255,.8)}
.flow__step--ai .flow__n{background:rgba(255,255,255,.18);color:#fff}
.flow__line{width:2px;height:30px;background:repeating-linear-gradient(to bottom,var(--blue-2) 0 4px,transparent 4px 8px);position:relative}
.flow__line::after{content:"";position:absolute;inset:0;background:linear-gradient(to bottom,transparent,#fff);animation:flowdown 1.6s linear infinite}
@keyframes flowdown{from{transform:translateY(-100%)}to{transform:translateY(100%)}}
.flow__split{display:grid;grid-template-columns:1fr 1fr;gap:12px;width:100%}
.flow__split .flow__step{max-width:none;padding:12px}

/* Voicebot */
.pills{display:grid;gap:12px}
.pill{padding:16px 18px;border-radius:14px;background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.1)}
.pill b{display:block;margin-bottom:2px}
.pill span{color:rgba(226,232,240,.7);font-size:.93rem}
.call{background:linear-gradient(160deg,var(--navy-3),var(--navy-2));border:1px solid rgba(255,255,255,.1);border-radius:22px;padding:26px;box-shadow:0 30px 70px rgba(0,0,0,.4)}
.call__head{display:flex;align-items:center;gap:14px;margin-bottom:22px}
.call__head small{display:flex;align-items:center;gap:6px;color:rgba(226,232,240,.65)}
.call__avatar{width:48px;height:48px;border-radius:14px;background:linear-gradient(135deg,var(--blue-2),var(--blue-dk));display:grid;place-items:center}
.call__avatar img{width:30px}
.live{width:8px;height:8px;border-radius:50%;background:#34D399;animation:pulse 1.6s infinite}
@keyframes pulse{0%{box-shadow:0 0 0 0 rgba(52,211,153,.6)}100%{box-shadow:0 0 0 10px rgba(52,211,153,0)}}
.wave{display:flex;align-items:center;justify-content:center;gap:4px;height:64px;margin-bottom:22px}
.wave i{width:4px;border-radius:4px;background:linear-gradient(to top,var(--blue-2),#A78BFA);height:var(--h,30%);animation:wave 1.2s ease-in-out infinite}
.wave i:nth-child(2n){--h:55%}.wave i:nth-child(3n){--h:80%}.wave i:nth-child(5n){--h:40%}.wave i:nth-child(7n){--h:95%}
.wave i:nth-child(3n){animation-delay:-.2s}.wave i:nth-child(3n+1){animation-delay:-.5s}.wave i:nth-child(4n){animation-delay:-.8s}.wave i:nth-child(5n){animation-delay:-1s}
@keyframes wave{0%,100%{height:var(--h,30%)}50%{height:15%}}
.call__lines{display:grid;gap:10px}
.call__lines p{margin:0;padding:10px 14px;border-radius:12px;font-size:.88rem;max-width:88%}
.call__lines .bot{background:rgba(59,130,246,.16);border:1px solid rgba(96,165,250,.25)}
.call__lines .cus{justify-self:end;background:rgba(255,255,255,.07)}

/* Pricing */
.pricing{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;align-items:stretch}
.plan{position:relative;background:#fff;border:1px solid var(--line);border-radius:20px;padding:32px;display:flex;flex-direction:column}
.plan__desc{color:var(--ink-3);font-size:.93rem;min-height:3em}
.plan__price{display:flex;align-items:baseline;flex-wrap:wrap;gap:6px;margin:6px 0 24px}
.plan__price b{font-size:2.25rem;font-weight:800;letter-spacing:-.03em}
.plan__price span{color:var(--ink-3);font-size:.9rem}
.plan__list{list-style:none;padding:0;margin:26px 0 0;display:grid;gap:12px;font-size:.93rem;color:var(--ink-2)}
.plan__list li{position:relative;padding-left:28px}
.plan__list li::before{content:"";position:absolute;left:0;top:3px;width:18px;height:18px;border-radius:50%;background:#DBEAFE url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%231D4ED8' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12l5 5 9-10'/%3E%3C/svg%3E") center/11px no-repeat}
.plan--featured{border:2px solid var(--blue);box-shadow:0 20px 50px rgba(37,99,235,.18);transform:translateY(-8px)}
.plan__badge{position:absolute;top:-13px;left:32px;background:linear-gradient(135deg,var(--blue-2),var(--blue-dk));color:#fff;font-size:.75rem;font-weight:700;padding:4px 12px;border-radius:999px}
.pricing__note{text-align:center;color:var(--ink-3);font-size:.875rem;margin-top:32px}

/* FAQ */
.faq{display:grid;gap:12px}
.faq details{border:1px solid var(--line);border-radius:14px;padding:0 22px;background:#fff;transition:border-color .2s}
.faq details[open]{border-color:#C7D7FE}
.faq summary{list-style:none;cursor:pointer;padding:20px 0;font-weight:600;display:flex;justify-content:space-between;gap:16px}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font-size:1.4rem;line-height:1;color:var(--blue);transition:transform .2s}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq p{color:var(--ink-3);padding-bottom:20px;margin:0}

/* CTA */
.cta{position:relative;overflow:hidden;background:var(--navy);color:#fff;padding:110px 0;text-align:center}
.hero__glow--cta{left:50%;right:auto;top:-500px;transform:translateX(-50%)}
.cta__inner{position:relative}
.cta p{color:rgba(226,232,240,.78);font-size:1.1rem;max-width:620px;margin:0 auto 40px}
.contact{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;max-width:620px;margin:0 auto}
.contact__item{display:flex;align-items:center;gap:14px;text-align:left;padding:18px 20px;border-radius:16px;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12);transition:background .2s,transform .2s}
.contact__item:hover{background:rgba(255,255,255,.1);transform:translateY(-2px)}
.contact__item small{display:block;color:rgba(226,232,240,.6);font-size:.78rem}
.contact__item b{font-weight:600;word-break:break-all}
.contact__icon{width:44px;height:44px;border-radius:12px;display:grid;place-items:center;flex:none;background:linear-gradient(135deg,var(--blue-2),var(--blue-dk))}
.contact__icon svg{width:20px;color:#fff}
.contact__icon .ci{width:22px;height:22px}

/* Footer */
.footer{background:#070C17;color:rgba(226,232,240,.65);padding:64px 0 28px;font-size:.92rem}
.footer__inner{display:flex;justify-content:space-between;gap:48px;flex-wrap:wrap;padding-bottom:40px;border-bottom:1px solid rgba(255,255,255,.08)}
.footer__brand{max-width:340px}
.footer__brand img{height:50px;width:auto;margin-bottom:16px}
.footer__cols{display:flex;gap:72px}
.footer__cols>div{display:flex;flex-direction:column;gap:10px}
.footer h4{color:#fff;font-size:.9rem;margin-bottom:6px}
.footer a:hover{color:#fff}
.footer__bottom{display:flex;justify-content:space-between;padding-top:24px;font-size:.85rem}

/* reveal */
.reveal{opacity:0;transform:translateY(18px);transition:opacity .7s ease,transform .7s ease}
.reveal.is-in{opacity:1;transform:none}

/* ============ RESPONSIVE ============ */
@media (max-width:1024px){
  .hero__inner,.split{grid-template-columns:1fr;gap:48px}
  .split--rev .split__copy{order:0}
  .mock{transform:none}
  .grid--3{grid-template-columns:1fr 1fr}
  .plan{padding:26px 22px}
}
@media (max-width:900px){
  .nav__links{position:fixed;inset:72px 0 auto;flex-direction:column;gap:0;background:#fff;padding:8px 16px 16px;border-bottom:1px solid var(--line);box-shadow:0 20px 40px rgba(15,23,42,.12);transform:translateY(-8px);opacity:0;pointer-events:none;transition:opacity .2s,transform .2s}
  .nav__links a{color:var(--ink-2)!important;padding:14px 8px;border-bottom:1px solid var(--line)}
  .nav.is-open .nav__links{opacity:1;transform:none;pointer-events:auto}
  .nav.is-open{background:#fff}
  .nav.is-open .logo--light{display:none}.nav.is-open .logo--dark{display:block}
  .nav.is-open .nav__burger span{background:var(--ink)}
  .nav.is-open .lang{border-color:var(--line)}.nav.is-open .lang span{color:var(--ink-3)}
  html[lang=vi] .nav.is-open .lang [data-lang=vi],html[lang=en] .nav.is-open .lang [data-lang=en]{background:var(--navy);color:#fff}
  .nav.is-open .nav__burger span:first-child{transform:translateY(4px) rotate(45deg)}
  .nav.is-open .nav__burger span:last-child{transform:translateY(-4px) rotate(-45deg)}
  .nav__burger{display:flex}
  .pricing{grid-template-columns:1fr;max-width:480px;margin:0 auto}
  .plan--featured{transform:none}
  .nav__actions{margin-left:auto}
  .nav__actions .btn{display:none}
}
@media (max-width:720px){
  .container{padding:0 16px}
  .hero{padding:120px 0 72px}
  .section,.cta{padding:76px 0}
  .grid--3,.pricing,.contact{grid-template-columns:1fr}
  .mock__body{grid-template-columns:1fr}
  .mock__list{display:none}
  .strip__inner{justify-content:center;text-align:center}
  .strip__logos{justify-content:center;gap:22px}
  .ci--lg{width:28px;height:28px}
  .footer__cols{gap:40px}
  .footer__bottom{flex-direction:column;gap:8px}
  .flow{padding:20px}
  .flow__split{grid-template-columns:1fr}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important}
  html{scroll-behavior:auto}
  .reveal{opacity:1;transform:none}
}