/* EdT365 QR — landing page
   Brand: Edtech365 Solutions Việt Nam (Gold + Graphite + Ivory).
   Palette tokens mirror edtech365.vn/assets/styles.css so the two sites read as one brand.
   Red stays in the logo/app-icon only (mệnh Kim: avoid Fire colours in the UI). */
:root{
  --gold-d:#8A6A15; --gold-dd:#6E5410; --gold:#C8992F; --gold-l:#E7C877;
  --ink:#2B2F35; --slate:#4A4E55; --muted:#6E6C6A; --line:#E9E4DA;
  --bg:#FBF6EC; --white:#FFFFFF;
  --grad:linear-gradient(135deg,#2B2F35 0%,#464D57 100%);
  --grad-gold:linear-gradient(135deg,#A9791A 0%,#E7C877 55%,#B8862B 100%);
  --grad-soft:linear-gradient(135deg,#FCF7EE 0%,#F5EAD3 100%);
  --shadow:0 10px 30px -12px rgba(43,47,53,.18);
  --shadow-lg:0 26px 56px -20px rgba(43,47,53,.28);
  --radius:18px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;color:var(--ink);background:var(--white);line-height:1.65;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4{font-family:'Be Vietnam Pro',-apple-system,sans-serif;line-height:1.2;letter-spacing:-.02em}
a{color:inherit;text-decoration:none}
img,svg{max-width:100%}
.wrap{max-width:1160px;margin:0 auto;padding:0 24px}
section{padding:88px 0;scroll-margin-top:82px}

/* language toggle — .block must precede .en (same specificity, later rule wins) */
.block{display:block}
.en{display:none}
[data-lang="en"] .vi{display:none}
[data-lang="en"] .en{display:inline}
[data-lang="en"] .en.block{display:block}
.skip{position:absolute;left:-9999px;top:0;background:#fff;padding:10px 16px;border-radius:10px;z-index:100}
.skip:focus{left:16px;top:12px;box-shadow:var(--shadow)}

/* ---------- Header ---------- */
header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.85);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
header.up{box-shadow:0 6px 22px -16px rgba(43,47,53,.5)}
.nav{display:flex;align-items:center;justify-content:space-between;height:72px;gap:18px}
.brand{display:flex;align-items:center;gap:11px}
.brand img{height:40px;width:40px;border-radius:11px;box-shadow:0 4px 12px -4px rgba(43,47,53,.35)}
.brand .bt{font-family:'Be Vietnam Pro',sans-serif;font-weight:800;font-size:19px;line-height:1.1}
.brand small{display:block;font-size:9px;font-weight:700;letter-spacing:2.2px;color:var(--muted)}
.gold-text{background:var(--grad-gold);-webkit-background-clip:text;background-clip:text;color:transparent}
.menu{display:flex;gap:26px;align-items:center}
.menu a{font-size:14.5px;font-weight:500;color:var(--slate);transition:color .2s;white-space:nowrap}
.menu a:hover{color:var(--gold-d)}
.actions{display:flex;align-items:center;gap:13px}
.lang{display:flex;border:1px solid var(--line);border-radius:999px;overflow:hidden;font-size:13px;font-weight:600}
.lang button{border:0;background:transparent;padding:7px 13px;cursor:pointer;color:var(--muted);font:inherit}
.lang button.on{background:var(--grad);color:#fff}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;white-space:nowrap;padding:12px 22px;border-radius:999px;font-weight:600;font-size:14.5px;cursor:pointer;border:0;transition:transform .18s,box-shadow .18s,border-color .2s,color .2s}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 10px 24px -8px rgba(43,47,53,.34)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 30px -8px rgba(43,47,53,.42)}
.btn-ghost{background:#fff;color:var(--ink);border:1px solid var(--line)}
.btn-ghost:hover{border-color:var(--gold-d);color:var(--gold-d)}
.burger{display:none;background:none;border:0;cursor:pointer;padding:6px}
.burger span{display:block;width:24px;height:2px;background:var(--ink);margin:5px 0;border-radius:2px;transition:.2s}

/* ---------- Hero ---------- */
.hero{position:relative;overflow:hidden;background:var(--grad-soft);padding:72px 0 84px}
.hero:before{content:"";position:absolute;top:-150px;right:-130px;width:500px;height:500px;background:radial-gradient(circle,rgba(200,153,47,.26),transparent 65%);border-radius:50%}
.hero:after{content:"";position:absolute;bottom:-170px;left:-130px;width:470px;height:470px;background:radial-gradient(circle,rgba(43,47,53,.12),transparent 65%);border-radius:50%}
.hero-grid{position:relative;display:grid;grid-template-columns:1.08fr .92fr;gap:52px;align-items:center}
.eyebrow{display:inline-flex;align-items:center;gap:9px;background:#fff;border:1px solid var(--line);color:var(--gold-d);font-weight:600;font-size:13px;padding:7px 15px;border-radius:999px;box-shadow:var(--shadow)}
.dot{width:8px;height:8px;border-radius:50%;background:var(--gold);box-shadow:0 0 0 4px rgba(200,153,47,.24)}
.hero h1{font-size:clamp(33px,4.8vw,54px);font-weight:800;margin:22px 0 18px}
.hero p.lead{font-size:18px;color:var(--slate);max-width:560px}
.hero-cta{display:flex;gap:16px;flex-wrap:wrap;align-items:center;margin-top:30px}
.badge-link{display:inline-block;transition:transform .18s}
.badge-link:hover{transform:translateY(-2px)}
.badge-link img{height:54px;width:auto;display:block}
.hero-mini{display:flex;gap:30px;margin-top:34px;flex-wrap:wrap}
.hero-mini b{font-family:'Be Vietnam Pro',sans-serif;font-size:26px;font-weight:800;display:block}
.hero-mini span{font-size:13px;color:var(--muted)}

/* scan-to-download card */
.scan-card{display:flex;align-items:center;gap:16px;background:#fff;border:1px solid var(--line);border-radius:18px;padding:14px 18px 14px 14px;box-shadow:var(--shadow);max-width:330px}
.scan-card img{width:92px;height:92px;border-radius:12px}
/* NOTE: never style bare `span` inside a container that holds .vi/.en language spans —
   `.scan-card span{display:block}` beats `.en{display:none}` on specificity and both
   languages render at once. Style the wrapper classes instead. */
.scan-card b{font-family:'Be Vietnam Pro',sans-serif;font-size:15px;display:block}
.scan-card .txt p{font-size:12.5px;color:var(--muted);line-height:1.5;margin-top:2px}

/* phone mockup.
   Screenshots are native 1320×2868 (19.5:9) — at full height a phone is 2.17× its own width
   and towers over everything around it. So we crop: the frame keeps a set height and the
   image is object-fit:cover anchored to the top, which keeps the status bar + title + QR
   (the part worth showing) and drops the tail of the scroll view. */
.phone{position:relative;width:min(272px,74vw);margin:0 auto;border-radius:42px;padding:10px;background:linear-gradient(160deg,#3A3F47,#22252A 45%,#3A3F47);box-shadow:var(--shadow-lg),0 0 0 1px rgba(43,47,53,.35)}
.phone img{display:block;width:100%;height:clamp(330px,42vw,470px);object-fit:cover;object-position:top center;border-radius:33px;background:#0f1115}
.phone.tilt{transform:rotate(-3deg)}
/* the crop line is hidden by fading the whole frame out into the section background */
.phone.fade{-webkit-mask-image:linear-gradient(180deg,#000 74%,transparent 99%);mask-image:linear-gradient(180deg,#000 74%,transparent 99%)}
/* the hero has more vertical room than a gallery cell, so its phone shows a bit more */
.hero .phone{width:min(292px,76vw)}
.hero .phone img{height:clamp(400px,36vw,540px)}
.float-badge{position:absolute;background:#fff;border-radius:14px;box-shadow:var(--shadow);padding:11px 15px;display:flex;align-items:center;gap:10px;font-weight:600;font-size:13px;z-index:2}
.fb1{top:44px;left:-58px}
.fb2{bottom:64px;right:-52px}
.ico{width:32px;height:32px;border-radius:9px;display:grid;place-items:center;color:#fff;flex:0 0 32px}
.ico-gold{background:var(--grad-gold)}
.ico-ink{background:var(--grad)}
.ico-soft{background:var(--grad-soft);color:var(--gold-d)}

/* ---------- Migration notice ---------- */
.notice{background:var(--ink);color:#EDE8DD;padding:26px 0}
.notice .wrap{display:flex;align-items:center;gap:18px;flex-wrap:wrap;justify-content:center;text-align:center}
.notice .ico{flex:0 0 40px;width:40px;height:40px;border-radius:12px}
.notice p{font-size:15px;max-width:820px;color:#D8D1C5}
.notice b{color:var(--gold-l)}

/* ---------- Sections ---------- */
.tag{display:inline-block;color:var(--gold-d);font-weight:700;font-size:13px;letter-spacing:2px;text-transform:uppercase;margin-bottom:12px}
.sec-title{font-size:clamp(26px,3.4vw,38px);font-weight:800;max-width:760px}
.sec-sub{color:var(--slate);font-size:17px;max-width:660px;margin-top:14px}
.center{text-align:center}
.center .sec-title,.center .sec-sub{margin-left:auto;margin-right:auto}

/* QR type chips */
.types{background:var(--bg)}
.chips{display:flex;flex-wrap:wrap;gap:12px;justify-content:center;margin-top:38px}
.chip{display:inline-flex;align-items:center;gap:9px;background:#fff;border:1px solid var(--line);border-radius:999px;padding:11px 18px;font-weight:600;font-size:14.5px;box-shadow:0 4px 14px -10px rgba(43,47,53,.4)}
.chip svg{color:var(--gold-d)}
.chip.hot{border-color:rgba(200,153,47,.55);background:var(--grad-soft)}

/* Feature cards */
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:44px}
.card{background:#fff;border:1px solid var(--line);border-top:3px solid var(--gold);border-radius:var(--radius);padding:28px 24px;box-shadow:var(--shadow);transition:transform .2s,box-shadow .2s}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.card .ico{width:44px;height:44px;border-radius:13px;margin-bottom:16px}
.card h3{font-size:19px;font-weight:700;margin-bottom:9px}
.card p{color:var(--slate);font-size:15px}

/* Screenshot gallery */
.shots{background:var(--grad-soft);position:relative;overflow:hidden}
.shot-row{display:grid;grid-template-columns:repeat(4,1fr);gap:26px;margin-top:46px}
.shot{text-align:center}
.shot .phone{width:100%;max-width:250px}
.shot b{display:block;font-family:'Be Vietnam Pro',sans-serif;font-size:16px;margin-top:18px}
.shot figcaption{font-size:13.5px;color:var(--muted);margin-top:4px}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:44px}
.step{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px 24px;position:relative;box-shadow:var(--shadow)}
.step .n{font-family:'Be Vietnam Pro',sans-serif;font-weight:800;font-size:40px;line-height:1;background:var(--grad-gold);-webkit-background-clip:text;background-clip:text;color:transparent;margin-bottom:12px;display:block}
.step h3{font-size:18px;margin-bottom:8px}
.step p{color:var(--slate);font-size:15px}
.step-qr{display:flex;align-items:center;gap:22px;justify-content:center;margin-top:44px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px 26px;box-shadow:var(--shadow);max-width:620px;margin-left:auto;margin-right:auto;flex-wrap:wrap}
.step-qr img{width:150px;height:150px;border-radius:14px}
.step-qr b{font-family:'Be Vietnam Pro',sans-serif;font-size:18px;display:block;margin-bottom:6px}
.step-qr p{color:var(--slate);font-size:14.5px;max-width:290px}

/* Trust band */
.trust{background:var(--ink);color:#fff}
.trust .tag{color:var(--gold-l)}
.trust .sec-sub{color:#C9C2B6}
.trust-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;margin-top:44px}
.trust-grid div{background:rgba(255,255,255,.05);border:1px solid rgba(231,200,119,.18);border-radius:var(--radius);padding:24px 22px}
.trust-grid .ico{width:40px;height:40px;border-radius:12px;margin-bottom:14px}
.trust-grid h3{font-size:17px;margin-bottom:7px;color:var(--gold-l)}
.trust-grid p{font-size:14.5px;color:#C9C2B6}

/* FAQ */
.faq{max-width:840px;margin:44px auto 0;display:grid;gap:14px}
.faq details{background:#fff;border:1px solid var(--line);border-radius:16px;padding:0 22px;box-shadow:0 6px 20px -16px rgba(43,47,53,.55)}
.faq summary{cursor:pointer;list-style:none;font-family:'Be Vietnam Pro',sans-serif;font-weight:700;font-size:16.5px;padding:20px 34px 20px 0;position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary:after{content:"";position:absolute;right:4px;top:27px;width:9px;height:9px;border-right:2px solid var(--gold-d);border-bottom:2px solid var(--gold-d);transform:rotate(45deg);transition:transform .2s}
.faq details[open] summary:after{transform:rotate(-135deg)}
.faq p{color:var(--slate);font-size:15.5px;padding-bottom:22px}
.faq a{color:var(--gold-d);font-weight:600;text-decoration:underline}

/* CTA band */
.cta{background:var(--grad);color:#fff;text-align:center;position:relative;overflow:hidden}
.cta:before{content:"";position:absolute;top:-160px;left:50%;transform:translateX(-50%);width:640px;height:640px;background:radial-gradient(circle,rgba(199,154,34,.22),transparent 62%);border-radius:50%}
.cta .wrap{position:relative}
.cta h2{font-size:clamp(27px,3.6vw,40px);font-weight:800;max-width:760px;margin:0 auto}
.cta p{color:#D8D1C5;font-size:17px;max-width:600px;margin:16px auto 0}
.cta-row{display:flex;gap:16px;justify-content:center;align-items:center;flex-wrap:wrap;margin-top:32px}
.cta .btn-ghost{background:rgba(255,255,255,.12);color:#fff;border:1px solid rgba(255,255,255,.3)}
.cta .btn-ghost:hover{background:rgba(255,255,255,.2);color:#fff}

/* ---------- Footer ---------- */
footer{background:#1F2226;color:#A9A299;padding:64px 0 28px;font-size:14.5px}
.foot-grid{display:grid;grid-template-columns:1.5fr 1fr 1.2fr;gap:40px}
.foot-brand{display:flex;align-items:center;gap:14px}
.foot-brand img{height:58px;width:auto}
.foot-brand .fw{font-family:'Be Vietnam Pro',sans-serif;font-weight:800;font-size:21px;color:#fff;line-height:1}
.foot-brand small{display:block;font-size:9px;font-weight:700;letter-spacing:2.4px;margin-top:4px}
.foot-brand .pillars{font-size:8.5px;font-weight:700;letter-spacing:1px;color:var(--gold);margin-top:3px;display:block}
footer .slogan{font-style:italic;color:var(--gold-l);font-weight:600;margin-top:14px;max-width:320px}
footer h5{color:#fff;font-family:'Be Vietnam Pro',sans-serif;font-size:15px;margin-bottom:16px}
footer ul{list-style:none;display:grid;gap:9px}
footer a:hover{color:var(--gold-l)}
.contact-line{display:flex;gap:10px;align-items:flex-start;margin-bottom:11px}
.contact-line svg{flex:0 0 18px;margin-top:3px;color:var(--gold)}
.pn>span{margin-left:.28em}
.copyright{border-top:1px solid rgba(255,255,255,.1);margin-top:44px;padding-top:22px;display:grid;gap:6px;font-size:13px;color:#8B857D}

/* reveal on scroll */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .6s ease,transform .6s ease}
.reveal.in{opacity:1;transform:none}
@media (prefers-reduced-motion:reduce){
  .reveal{opacity:1;transform:none;transition:none}
  html{scroll-behavior:auto}
}

/* to-top button (injected by site.js) */
#toTop{position:fixed;right:20px;bottom:22px;width:44px;height:44px;border-radius:50%;border:0;background:var(--grad);color:#fff;cursor:pointer;display:grid;place-items:center;opacity:0;visibility:hidden;transition:.25s;box-shadow:var(--shadow-lg);z-index:60}
#toTop.show{opacity:1;visibility:visible}

/* ---------- Responsive ---------- */
@media (max-width:980px){
  .hero-grid{grid-template-columns:1fr;gap:44px}
  .hero-visual{order:-1}
  .grid-3,.steps,.trust-grid{grid-template-columns:repeat(2,1fr)}
  .shot-row{grid-template-columns:repeat(2,1fr);gap:32px}
  .foot-grid{grid-template-columns:1fr 1fr}
  .fb1{left:-14px}.fb2{right:-10px}
}
/* The nav collapses at 900px, not 760: between those widths the 5 links + language
   toggle + CTA no longer fit on one 72px row and the header wraps/overflows. */
@media (max-width:900px){
  .menu{position:fixed;inset:72px 0 auto 0;background:#fff;flex-direction:column;align-items:flex-start;gap:0;padding:8px 24px 20px;border-bottom:1px solid var(--line);box-shadow:var(--shadow);display:none}
  .menu.open{display:flex}
  .menu a{padding:13px 0;width:100%;border-bottom:1px solid var(--line);font-size:16px}
  .burger{display:block}
}
@media (max-width:760px){
  section{padding:64px 0}
  .header-cta{display:none}
  .grid-3,.steps,.trust-grid,.shot-row{grid-template-columns:1fr}
  .shot .phone{max-width:270px}
  .foot-grid{grid-template-columns:1fr;gap:32px}
  .float-badge{display:none}
  .hero-mini{gap:22px}
  .step-qr{flex-direction:column;text-align:center}
}