:root{
  --bg:#f7fbff;--card:#fff;--text:#08111f;--muted:#607089;--line:#dce8f6;
  --brand:#126bff;--cyan:#10b8bd;--green:#12b85f;
  --shadow:0 18px 60px rgba(8,17,31,.10);--radius:28px;--max:1120px;
}
@media(prefers-color-scheme:dark){
  :root{--bg:#070b12;--card:#101827;--text:#f8fafc;--muted:#a6b2c6;--line:#26364d;--shadow:0 18px 60px rgba(0,0,0,.36)}
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Inter,Arial,sans-serif;
  color:var(--text);line-height:1.65;background:
    radial-gradient(circle at 0% 0%,rgba(18,107,255,.16),transparent 34%),
    radial-gradient(circle at 100% 0%,rgba(16,184,189,.15),transparent 32%),
    linear-gradient(180deg,#eff8ff00,#eff8ff66),var(--bg);
}
a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}
.wrap{width:min(var(--max),calc(100% - 32px));margin:auto}
.nav{position:sticky;top:0;z-index:50;background:rgba(247,251,255,.82);backdrop-filter:blur(18px);border-bottom:1px solid var(--line)}
@media(prefers-color-scheme:dark){.nav{background:rgba(7,11,18,.82)}}
.navin{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 0}
.brand{display:flex;align-items:center;gap:12px;color:var(--text);font-weight:950;font-size:20px}
.logo{width:46px;height:46px;border-radius:17px;background:linear-gradient(135deg,var(--brand),var(--cyan));display:grid;place-items:center;color:#fff;font-weight:950;box-shadow:0 14px 34px rgba(18,107,255,.24)}
.links{display:flex;align-items:center;gap:20px}.links a{color:var(--muted);font-weight:850;font-size:15px}
.menuToggle{display:none}
.menuButton{display:none;border:1px solid var(--line);background:var(--card);border-radius:14px;padding:10px 12px;font-weight:900;color:var(--text)}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:12px 18px;border-radius:999px;background:var(--text);color:var(--bg)!important;font-weight:950;box-shadow:0 12px 30px rgba(8,17,31,.15)}
.btn2{display:inline-flex;align-items:center;justify-content:center;padding:12px 18px;border-radius:999px;background:var(--card);border:1px solid var(--line);color:var(--text);font-weight:950}
.hero{padding:78px 0 42px}.heroGrid{display:grid;grid-template-columns:1.15fr .85fr;gap:34px;align-items:center}
.kicker{color:var(--brand);font-size:13px;text-transform:uppercase;letter-spacing:.13em;font-weight:950}
h1{font-size:clamp(38px,7vw,72px);line-height:1.02;letter-spacing:-.055em;margin:14px 0 18px}
h2{font-size:clamp(28px,4vw,44px);line-height:1.1;letter-spacing:-.035em;margin:0 0 16px}
h3{font-size:22px;line-height:1.2;margin:0 0 10px}.lead{font-size:20px;color:var(--muted);max-width:710px}
.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}
.device{background:linear-gradient(180deg,var(--card),rgba(255,255,255,.64));border:1px solid var(--line);border-radius:38px;padding:24px;box-shadow:var(--shadow);overflow:hidden}
@media(prefers-color-scheme:dark){.device{background:linear-gradient(180deg,var(--card),rgba(16,24,39,.68))}}
.screen{background:var(--card);border:1px solid var(--line);border-radius:30px;padding:22px;box-shadow:0 14px 42px rgba(8,17,31,.10)}
.topline{display:flex;justify-content:space-between;color:var(--muted);font-weight:900}
.power{width:156px;height:156px;border-radius:50%;display:grid;place-items:center;text-align:center;margin:24px auto;background:linear-gradient(180deg,#25d873,#07a84e);color:white;font-size:21px;font-weight:950;box-shadow:0 18px 42px rgba(7,168,78,.33)}
.profile{border:1px solid var(--line);border-radius:18px;padding:14px;font-weight:900;margin:12px 0}.chips{display:flex;gap:8px;flex-wrap:wrap}.chip{background:var(--bg);border:1px solid var(--line);color:var(--muted);font-weight:850;border-radius:999px;padding:7px 11px;font-size:13px}
.section{padding:54px 0}.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.card{background:rgba(255,255,255,.86);border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:0 10px 34px rgba(8,17,31,.06)}@media(prefers-color-scheme:dark){.card{background:rgba(16,24,39,.86)}}.card p{color:var(--muted);margin:0}
.docgrid{display:grid;grid-template-columns:248px 1fr;gap:28px;padding:42px 0}.side{position:sticky;top:88px;align-self:start;background:rgba(255,255,255,.86);border:1px solid var(--line);border-radius:22px;padding:14px;box-shadow:0 10px 34px rgba(8,17,31,.06)}@media(prefers-color-scheme:dark){.side{background:rgba(16,24,39,.86)}}.side a{display:block;color:var(--muted);font-weight:850;padding:10px 12px;border-radius:14px}.side a:hover{background:var(--bg);color:var(--brand);text-decoration:none}
.doc{background:rgba(255,255,255,.90);border:1px solid var(--line);border-radius:30px;padding:36px;box-shadow:var(--shadow)}@media(prefers-color-scheme:dark){.doc{background:rgba(16,24,39,.90)}}.doc h1{font-size:46px;margin-top:0}.doc h2{font-size:28px;margin-top:34px}.doc p,.doc li{color:var(--muted)}.doc strong{color:var(--text)}.doc ul{padding-left:22px}
.notice{padding:16px 18px;border-radius:18px;background:var(--bg);border:1px solid var(--line);font-weight:750;color:var(--muted)}
.footer{border-top:1px solid var(--line);padding:28px 0;color:var(--muted);font-size:14px}.footin{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}
@media(max-width:860px){
  .navin{flex-wrap:wrap}.brand{font-size:19px}.menuButton{display:inline-flex}.links{display:none;width:100%;padding-top:10px;border-top:1px solid var(--line);flex-wrap:wrap;gap:8px}
  .links a{display:inline-flex;padding:8px 10px;border-radius:12px;background:rgba(255,255,255,.45)}
  @media(prefers-color-scheme:dark){.links a{background:rgba(16,24,39,.55)}}
  .menuToggle:checked ~ .links{display:flex}
  .hero{padding:48px 0 24px}.heroGrid,.grid3,.docgrid{grid-template-columns:1fr}.doc{padding:24px}.doc h1{font-size:38px}.side{position:static}.power{width:138px;height:138px}.lead{font-size:18px}
}


.langSwitcher{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);background:var(--card);border-radius:999px;padding:5px;box-shadow:0 8px 24px rgba(8,17,31,.06)}
.langBtn{border:0;background:transparent;color:var(--muted);font-weight:950;border-radius:999px;padding:8px 12px;cursor:pointer;font:inherit;font-size:14px;line-height:1}
html[data-lang="vi"] .langBtn[data-set-lang="vi"],html[data-lang="en"] .langBtn[data-set-lang="en"]{background:var(--brand);color:#fff}
html[data-lang="vi"] .lang-en{display:none!important}html[data-lang="en"] .lang-vi{display:none!important}
.versionBadge{display:inline-flex;align-items:center;gap:8px;border:1px solid var(--line);background:var(--card);border-radius:999px;padding:9px 13px;color:var(--muted);font-weight:900;font-size:14px}
.featureList{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:18px}.featureList .card{padding:18px}
.small{font-size:14px;color:var(--muted)}
.table{width:100%;border-collapse:collapse;margin:18px 0}.table th,.table td{border:1px solid var(--line);padding:12px;text-align:left;vertical-align:top}.table th{background:var(--bg);color:var(--text)}
.callout{border-left:4px solid var(--brand);padding:14px 16px;background:var(--bg);border-radius:14px;color:var(--muted)}
@media(max-width:860px){.langSwitcher{order:3}.featureList{grid-template-columns:1fr}.navin{gap:10px}.langBtn{padding:8px 10px}}