/* =========================================================
   VLABEL — Design System
   HTML5 · CSS3 · Vanilla JS  (no framework)
   ========================================================= */

/* ---------- Design tokens ---------- */
:root {
  /* Brand — teal, gợi tin cậy + công nghệ */
  --brand-50:  #f0fdfa;
  --brand-100: #ccfbf1;
  --brand-200: #99f6e4;
  --brand-300: #5eead4;
  --brand-400: #2dd4bf;
  --brand-500: #14b8a6;
  --brand-600: #0d9488;
  --brand-700: #0f766e;
  --brand-800: #115e59;

  /* Accent phụ — cyan/indigo cho cảm giác AI, data */
  --accent-1: #22d3ee;
  --accent-2: #6366f1;

  /* Neutrals */
  --ink:       #0b1220;   /* nền tối cao cấp */
  --ink-2:     #111a2e;
  --slate-900: #0f172a;
  --slate-800: #1e293b;
  --slate-700: #334155;
  --slate-600: #475569;
  --slate-500: #64748b;
  --slate-400: #94a3b8;
  --slate-300: #cbd5e1;
  --slate-200: #e2e8f0;
  --slate-100: #f1f5f9;
  --slate-50:  #f8fafc;
  --white:     #ffffff;

  /* Semantic */
  --bg: var(--white);
  --text: var(--slate-900);
  --text-soft: var(--slate-600);
  --text-muted: var(--slate-500);
  --border: var(--slate-200);
  --amber: #f59e0b;

  /* Typography */
  --font: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-display: "Space Grotesk", var(--font);

  /* Rhythm */
  --wrap: 1200px;
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 22px;
  --radius-xl: 30px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(15,23,42,.05);
  --shadow: 0 1px 2px rgba(15,23,42,.04), 0 10px 30px -14px rgba(15,23,42,.16);
  --shadow-lg: 0 2px 6px rgba(15,23,42,.05), 0 30px 60px -24px rgba(13,148,136,.28);

  --ease: cubic-bezier(.22,.61,.36,1);
  --dur: .55s;
}

/* ---------- Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

h1, h2, h3 { line-height: 1.15; font-weight: 700; letter-spacing: -.02em; color: var(--text); }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, textarea { font: inherit; }
ul { list-style: none; padding: 0; }

.icon { width: 1.25em; height: 1.25em; fill: none; stroke: currentColor; flex: none; }

.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: clamp(20px, 5vw, 40px); }

.mono { font-family: var(--font-display); letter-spacing: 0; }
.grad-text {
  background: linear-gradient(100deg, var(--brand-500), var(--accent-1) 55%, var(--accent-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.link { color: var(--brand-700); font-weight: 600; text-underline-offset: 3px; }
.link:hover { text-decoration: underline; }

/* Accessibility */
.skip-link {
  position: fixed; top: -100px; left: 16px; z-index: 200;
  background: var(--brand-600); color: #fff; padding: 10px 18px; border-radius: 10px;
  transition: top .2s;
}
.skip-link:focus { top: 16px; }
:focus-visible { outline: 3px solid var(--brand-500); outline-offset: 3px; border-radius: 6px; }

/* Scroll progress */
.scroll-progress { position: fixed; top: 0; left: 0; right: 0; height: 3px; z-index: 120; background: transparent; }
.scroll-progress span {
  display: block; height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--brand-500), var(--accent-1));
  transition: width .1s linear;
}

/* =========================================================
   BUTTONS
   ========================================================= */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font-weight: 600; font-size: .95rem; padding: .8rem 1.4rem;
  border-radius: var(--radius-sm); transition: transform .2s var(--ease), box-shadow .25s, background .2s, color .2s, border-color .2s;
  white-space: nowrap; will-change: transform;
}
.btn .icon { width: 1.1em; height: 1.1em; }
.btn-sm { padding: .6rem 1.05rem; font-size: .875rem; }
.btn-lg { padding: .95rem 1.7rem; font-size: 1rem; }
.btn-block { width: 100%; }

.btn-primary { background: var(--brand-600); color: #fff; box-shadow: 0 8px 22px -10px rgba(13,148,136,.7); }
.btn-primary:hover { background: var(--brand-700); box-shadow: var(--shadow-lg); transform: translateY(-2px); }
.btn-outline { border: 1.5px solid var(--slate-300); color: var(--text); background: var(--white); }
.btn-outline:hover { border-color: var(--brand-400); color: var(--brand-700); transform: translateY(-2px); }
.btn-ghost { color: var(--text-soft); }
.btn-ghost:hover { color: var(--brand-700); }

/* On dark surfaces */
.section-dark .btn-outline, .contact-info .btn-outline { border-color: rgba(255,255,255,.25); color: #fff; background: transparent; }

/* =========================================================
   HEADER
   ========================================================= */
.site-header {
  position: sticky; top: 0; z-index: 100;
  transition: background .3s, border-color .3s, backdrop-filter .3s;
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: rgba(255,255,255,.8);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom-color: var(--border);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; height: 72px; }

.brand { display: inline-flex; align-items: center; gap: .65rem; }
.brand-mark {
  width: 38px; height: 38px; border-radius: 11px; display: grid; place-items: center;
  background: linear-gradient(140deg, var(--brand-500), var(--brand-700)); color: #fff;
  box-shadow: 0 6px 16px -6px rgba(13,148,136,.6);
}
.brand-mark .icon { width: 21px; height: 21px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.05; }
.brand-name { font-weight: 800; font-size: 1.2rem; letter-spacing: -.02em; }
.brand-tag { font-size: .68rem; color: var(--text-muted); font-weight: 500; letter-spacing: .01em; }

.nav { display: flex; align-items: center; gap: 1.9rem; }
.nav-link { font-size: .93rem; font-weight: 500; color: var(--text-soft); position: relative; padding: .25rem 0; transition: color .2s; }
.nav-link::after {
  content: ""; position: absolute; left: 0; bottom: -2px; height: 2px; width: 0;
  background: var(--brand-500); border-radius: 2px; transition: width .25s var(--ease);
}
.nav-link:hover, .nav-link.active { color: var(--brand-700); }
.nav-link:hover::after, .nav-link.active::after { width: 100%; }

.header-cta { display: flex; align-items: center; gap: .6rem; }
.nav-toggle { display: none; width: 44px; height: 44px; border-radius: 11px; border: 1px solid var(--border); place-items: center; color: var(--text); }
.nav-toggle .icon { width: 22px; height: 22px; }

.mobile-nav {
  display: none; flex-direction: column; gap: .25rem;
  position: absolute; left: 0; right: 0; top: 100%;
  padding: 1rem clamp(20px,5vw,40px) 1.4rem; background: #fff;
  border-bottom: 1px solid var(--border);
  box-shadow: 0 24px 40px -20px rgba(15,23,42,.25);
  max-height: calc(100dvh - 64px); overflow-y: auto;
}
.mobile-nav a { padding: .85rem .5rem; font-weight: 500; color: var(--text-soft); border-radius: 10px; }
.mobile-nav a:hover, .mobile-nav a:active { background: var(--brand-50); color: var(--brand-700); }
.mobile-nav .btn { margin-top: .6rem; }
/* Hamburger → X khi mở menu */
.nav-toggle .ic-close { display: none; }
.site-header.menu-open .nav-toggle .ic-open { display: none; }
.site-header.menu-open .nav-toggle .ic-close { display: block; }

/* =========================================================
   SECTION SCAFFOLD
   ========================================================= */
.section { padding: clamp(72px, 10vw, 120px) 0; position: relative; }
section[id] { scroll-margin-top: 90px; }
.section-tint { background: linear-gradient(180deg, var(--slate-50), #fff); }
.section-dark { background: radial-gradient(120% 120% at 50% 0%, #16233d 0%, var(--ink) 55%); color: #fff; }
.section-dark .section-title, .section-dark h3 { color: #fff; }
.section-dark .section-lead { color: var(--slate-300); }

.eyebrow {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em;
  color: var(--brand-700); background: var(--brand-50); border: 1px solid var(--brand-100);
  padding: .45rem .9rem; border-radius: 100px;
}
.eyebrow .icon { width: 1rem; height: 1rem; }
.eyebrow-invert { color: var(--brand-300); background: rgba(45,212,191,.1); border-color: rgba(45,212,191,.25); }

.section-title { font-size: clamp(1.7rem, 3.6vw, 2.75rem); margin-top: 1rem; }
.section-lead { font-size: clamp(1rem, 1.5vw, 1.18rem); color: var(--text-soft); margin-top: 1rem; max-width: 62ch; }
.section-lead.center { margin-inline: auto; }

.center-head { max-width: 760px; margin: 0 auto clamp(48px, 6vw, 72px); text-align: center; }
.center-head .section-lead { margin-inline: auto; }

.split-head { display: grid; grid-template-columns: 1.1fr .9fr; gap: 2rem 3rem; align-items: end; margin-bottom: clamp(40px, 5vw, 64px); }

/* =========================================================
   HERO
   ========================================================= */
.hero { position: relative; padding: clamp(56px, 8vw, 96px) 0 clamp(48px, 6vw, 72px); overflow: hidden; }
.hero-bg { position: absolute; inset: 0; z-index: -1; overflow: hidden; }
.hero-grid {
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(15,23,42,.045) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(15,23,42,.045) 1px, transparent 1px);
  background-size: 54px 54px;
  mask-image: radial-gradient(ellipse 75% 55% at 50% 30%, #000 30%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 75% 55% at 50% 30%, #000 30%, transparent 100%);
}
.mesh { position: absolute; border-radius: 50%; filter: blur(70px); opacity: .55; will-change: transform; }
.mesh-1 { width: 520px; height: 520px; background: radial-gradient(circle, var(--brand-300), transparent 65%); top: -140px; left: -80px; animation: drift 18s ease-in-out infinite; }
.mesh-2 { width: 460px; height: 460px; background: radial-gradient(circle, #a5b4fc, transparent 65%); top: -60px; right: -60px; animation: drift 22s ease-in-out infinite reverse; }
.mesh-3 { width: 420px; height: 420px; background: radial-gradient(circle, #7dd3fc, transparent 65%); bottom: -160px; left: 45%; animation: drift 20s ease-in-out infinite; }
@keyframes drift {
  0%,100% { transform: translate(0,0) scale(1); }
  50% { transform: translate(30px, 24px) scale(1.08); }
}

.hero-inner { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(2rem, 5vw, 4rem); align-items: center; }

.eyebrow-glow { position: relative; }
.eyebrow-glow .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--brand-500); box-shadow: 0 0 0 0 rgba(20,184,166,.6); animation: ping 2s var(--ease) infinite; }
@keyframes ping { 0% { box-shadow: 0 0 0 0 rgba(20,184,166,.55);} 70%,100% { box-shadow: 0 0 0 9px rgba(20,184,166,0);} }

.hero-title { font-size: clamp(2.2rem, 5.4vw, 4rem); letter-spacing: -.035em; margin-top: 1.3rem; }
.hero-sub { font-size: clamp(1.02rem, 1.6vw, 1.22rem); color: var(--text-soft); margin-top: 1.4rem; max-width: 40ch; }
.hero-sub strong { color: var(--text); font-weight: 600; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .8rem; margin-top: 2rem; }
.hero-badges { display: flex; flex-wrap: wrap; gap: 1.2rem 1.6rem; margin-top: 2.2rem; }
.hero-badges li { display: inline-flex; align-items: center; gap: .5rem; font-size: .9rem; font-weight: 500; color: var(--text-soft); }
.hero-badges .icon { width: 18px; height: 18px; padding: 3px; border-radius: 50%; background: var(--brand-100); color: var(--brand-700); }

/* Hero visual */
.hero-visual { position: relative; min-height: 420px; }
.qr-device {
  position: relative; z-index: 2; max-width: 360px; margin-inline: auto;
  background: rgba(255,255,255,.9); backdrop-filter: blur(12px);
  border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 1.3rem; box-shadow: var(--shadow-lg);
  transform-style: preserve-3d; transition: transform .18s var(--ease);
}
.qr-device-top { display: flex; justify-content: space-between; margin-bottom: 1rem; }
.qr-chip { display: inline-flex; align-items: center; gap: .45rem; font-size: .72rem; font-weight: 600; color: var(--brand-700); background: var(--brand-50); border: 1px solid var(--brand-100); padding: .35rem .7rem; border-radius: 100px; }
.live-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--brand-500); animation: ping 2s var(--ease) infinite; }
.qr-scan { position: relative; background: var(--slate-50); border: 1px solid var(--slate-200); border-radius: var(--radius); padding: 1.5rem; display: grid; place-items: center; overflow: hidden; }
.qr-art { width: 150px; height: 150px; color: var(--ink); }
.scan-line { position: absolute; left: 8%; right: 8%; height: 2px; top: 12%;
  background: linear-gradient(90deg, transparent, var(--brand-500), transparent);
  box-shadow: 0 0 14px 2px rgba(20,184,166,.6); animation: scan 2.6s var(--ease) infinite; }
@keyframes scan { 0%,100% { top: 12%; opacity: .2;} 50% { top: 84%; opacity: 1;} }
.qr-meta { margin-top: 1.1rem; display: grid; gap: .55rem; }
.qr-meta-row { display: flex; justify-content: space-between; font-size: .85rem; }
.qr-meta-row span { color: var(--text-muted); }
.qr-meta-row b { color: var(--text); font-weight: 600; }

.float-card {
  position: absolute; z-index: 3; display: flex; align-items: center; gap: .65rem;
  background: rgba(255,255,255,.92); backdrop-filter: blur(10px); border: 1px solid var(--border);
  padding: .7rem .9rem; border-radius: 14px; box-shadow: var(--shadow); will-change: transform;
}
.float-card b { font-size: .88rem; display: block; }
.float-card small { font-size: .72rem; color: var(--text-muted); }
.fc-ic { width: 34px; height: 34px; border-radius: 9px; display: grid; place-items: center; background: var(--slate-100); color: var(--slate-700); }
.fc-ic.ok { background: var(--brand-50); color: var(--brand-700); }
.fc-ic .icon { width: 18px; height: 18px; }
.fc-1 { top: 4%; right: -2%; }
.fc-2 { bottom: 20%; left: -6%; }
.fc-3 { bottom: -2%; right: 6%; }

/* Stat strip */
.stat-strip {
  margin-top: clamp(40px, 6vw, 72px); display: grid; grid-template-columns: repeat(4,1fr);
  gap: 1rem; padding: 1.6rem; background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius-lg); box-shadow: var(--shadow);
}
.stat { text-align: center; padding: .4rem; position: relative; }
.stat + .stat::before { content: ""; position: absolute; left: 0; top: 15%; bottom: 15%; width: 1px; background: var(--border); }
.stat-num { font-family: var(--font-display); font-size: clamp(1.8rem, 3vw, 2.5rem); font-weight: 700; color: var(--brand-700); display: block; letter-spacing: -.02em; }
.stat-label { font-size: .82rem; color: var(--text-muted); }

/* =========================================================
   PROBLEM / OPPORTUNITY
   ========================================================= */
.prob-layout { display: grid; grid-template-columns: 1.3fr .95fr; gap: clamp(1.5rem, 3vw, 3rem); align-items: start; }
.pain-list { display: grid; gap: .9rem; }
.pain-list li { display: flex; gap: 1rem; padding: 1.2rem 1.3rem; background: #fff; border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow-sm); transition: transform .2s var(--ease), border-color .2s, box-shadow .25s; }
.pain-list li:hover { transform: translateX(4px); border-color: var(--brand-200); box-shadow: var(--shadow); }
.pain-ic { flex: none; width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; background: var(--slate-100); color: var(--slate-700); }
.pain-ic .icon { width: 22px; height: 22px; }
.pain-list h3 { font-size: 1.05rem; }
.pain-list p { font-size: .92rem; color: var(--text-soft); margin-top: .2rem; }

.opp-card { position: sticky; top: 100px; padding: 2rem; border-radius: var(--radius-lg); color: #fff; box-shadow: var(--shadow-lg);
  background: radial-gradient(130% 130% at 0% 0%, var(--brand-600), var(--ink-2) 90%); }
.opp-card h3 { color: #fff; font-size: 1.4rem; margin: .9rem 0; }
.opp-card > p { color: rgba(255,255,255,.82); font-style: italic; }
.opp-flow { display: flex; flex-wrap: wrap; align-items: center; gap: .5rem; margin: 1.4rem 0 1.6rem; }
.opp-flow span { font-size: .8rem; font-weight: 600; padding: .35rem .7rem; border-radius: 8px; background: rgba(255,255,255,.12); border: 1px solid rgba(255,255,255,.16); }
.opp-flow .icon { width: 16px; height: 16px; color: var(--brand-300); }

/* =========================================================
   LEGAL FRAMEWORK
   ========================================================= */
.legal-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; }
.legal-card {
  position: relative; padding: 1.6rem; border-radius: var(--radius); overflow: hidden;
  background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.1);
  transition: transform .18s var(--ease), border-color .25s, background .25s;
}
.legal-card:hover { border-color: rgba(45,212,191,.4); background: rgba(255,255,255,.07); }
.legal-no { font-family: var(--font-display); font-size: .8rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--brand-300); }
.legal-card h3 { font-size: 1.2rem; margin: .5rem 0 .6rem; }
.legal-card p { font-size: .92rem; color: var(--slate-300); }
.legal-card--note { background: linear-gradient(140deg, rgba(245,158,11,.16), rgba(245,158,11,.04)); border-color: rgba(245,158,11,.35); }
.legal-badge { display: inline-block; font-size: .72rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--amber); }
.legal-card--note b { color: #fff; }

/* Spotlight hover (dùng biến từ JS) */
[data-spotlight] { position: relative; }
[data-spotlight]::before {
  content: ""; position: absolute; inset: 0; border-radius: inherit; opacity: 0; transition: opacity .3s; pointer-events: none;
  background: radial-gradient(240px circle at var(--mx,50%) var(--my,50%), rgba(45,212,191,.14), transparent 60%);
}
[data-spotlight]:hover::before { opacity: 1; }

.compliance-note { display: flex; gap: .9rem; align-items: flex-start; margin-top: 1.6rem; padding: 1.1rem 1.3rem;
  background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1); border-radius: var(--radius); }
.compliance-note .icon { width: 22px; height: 22px; color: var(--brand-300); flex: none; margin-top: 2px; }
.compliance-note p { font-size: .9rem; color: var(--slate-300); }

/* =========================================================
   BENTO GRID (Solutions)
   ========================================================= */
.bento { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; grid-auto-rows: 1fr; }
.bento-item {
  position: relative; padding: 1.8rem; border-radius: var(--radius-lg); background: #fff;
  border: 1px solid var(--border); box-shadow: var(--shadow-sm); overflow: hidden;
  transition: transform .2s var(--ease), box-shadow .3s, border-color .25s;
}
.bento-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--brand-200); }
.bento-lg { grid-row: span 2; background: linear-gradient(180deg, #fff, var(--brand-50)); }
.bento-wide { grid-column: span 2; }
.bento-ic { width: 52px; height: 52px; border-radius: 14px; display: grid; place-items: center; color: #fff;
  background: linear-gradient(140deg, var(--brand-500), var(--brand-700)); box-shadow: 0 8px 18px -8px rgba(13,148,136,.6); margin-bottom: 1.1rem; }
.bento-ic .icon { width: 26px; height: 26px; }
.bento-item h3 { font-size: 1.25rem; margin-bottom: .5rem; }
.bento-item p { color: var(--text-soft); font-size: .95rem; }
.chip-row { display: flex; flex-wrap: wrap; gap: .5rem; margin-top: 1.2rem; }
.chip-row li { font-size: .78rem; font-weight: 600; color: var(--brand-700); background: var(--brand-50); border: 1px solid var(--brand-100); padding: .3rem .7rem; border-radius: 8px; }

/* =========================================================
   GLASS CARDS (Benefits)
   ========================================================= */
.glass-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1.1rem; }
.glass-card {
  position: relative; padding: 1.7rem; border-radius: var(--radius-lg); overflow: hidden;
  background: rgba(255,255,255,.7); backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,.9); box-shadow: 0 1px 2px rgba(15,23,42,.04), 0 18px 40px -26px rgba(15,23,42,.25);
  transition: transform .2s var(--ease), box-shadow .3s;
}
.glass-card::after { content: ""; position: absolute; inset: 0 0 auto 0; height: 1px; background: linear-gradient(90deg, transparent, rgba(20,184,166,.5), transparent); }
.glass-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.g-ic { width: 48px; height: 48px; border-radius: 13px; display: grid; place-items: center; background: var(--brand-50); color: var(--brand-700); margin-bottom: 1rem; }
.g-ic .icon { width: 24px; height: 24px; }
.glass-card h3 { font-size: 1.12rem; margin-bottom: .4rem; }
.glass-card p { font-size: .92rem; color: var(--text-soft); }

/* =========================================================
   TECHNOLOGY — architecture diagram
   ========================================================= */
.tech-layout { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem, 5vw, 4rem); align-items: center; }
.tick-list { display: grid; gap: .8rem; margin-top: 1.6rem; }
.tick-list li { display: flex; align-items: center; gap: .7rem; font-size: .98rem; color: var(--slate-200); }
.tick-list .icon { width: 20px; height: 20px; padding: 3px; border-radius: 50%; background: rgba(45,212,191,.15); color: var(--brand-300); flex: none; }

.tech-diagram { position: relative; aspect-ratio: 1; max-width: 440px; margin-inline: auto; width: 100%; }
.net-lines { position: absolute; inset: 0; width: 100%; height: 100%; color: var(--brand-400); z-index: 0; }
.pulse-line { stroke-dasharray: 6 8; animation: dash 1.6s linear infinite; }
@keyframes dash { to { stroke-dashoffset: -28; } }
.node { position: absolute; z-index: 1; display: flex; flex-direction: column; align-items: center; gap: .35rem; width: 96px;
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.14); border-radius: 14px; padding: .7rem .5rem;
  backdrop-filter: blur(6px); text-align: center; }
.node .icon { width: 24px; height: 24px; color: var(--brand-300); }
.node span { font-size: .72rem; font-weight: 600; color: #fff; line-height: 1.25; }
.node-center { left: 50%; top: 50%; transform: translate(-50%,-50%); width: 118px;
  background: linear-gradient(140deg, var(--brand-600), var(--brand-800)); border-color: rgba(45,212,191,.5); box-shadow: 0 10px 30px -10px rgba(13,148,136,.7); }
.node-center .icon { color: #fff; width: 28px; height: 28px; }
.n-1 { left: 50%; top: 0; transform: translateX(-50%); }
.n-2 { right: 0; top: 22%; }
.n-3 { right: 0; bottom: 22%; }
.n-4 { left: 50%; bottom: 0; transform: translateX(-50%); }
.n-5 { left: 0; bottom: 22%; }
.node:not(.node-center) { animation: floaty 6s ease-in-out infinite; }
.n-2 { animation-delay: -1s; } .n-3 { animation-delay: -2s; } .n-4 { animation-delay: -3s; } .n-5 { animation-delay: -4s; }
@keyframes floaty { 0%,100% { transform: translateY(0) translateX(var(--tx,0)); } 50% { transform: translateY(-7px) translateX(var(--tx,0)); } }
.n-1, .n-4 { --tx: -50%; }

/* =========================================================
   TIMELINE (Workflow)
   ========================================================= */
.timeline { position: relative; display: grid; grid-template-columns: repeat(3,1fr); gap: 1.6rem 1.4rem; padding-top: 1rem; }
.timeline::before { content: ""; position: absolute; left: 0; right: 0; top: 34px; height: 2px;
  background: linear-gradient(90deg, var(--brand-200), var(--brand-400), var(--brand-200)); opacity: .5; }
.tl-item { position: relative; background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 1.4rem 1.4rem 1.3rem; box-shadow: var(--shadow-sm);
  transition: transform .2s var(--ease), box-shadow .3s, border-color .2s; }
.tl-item:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--brand-200); }
.tl-dot { position: absolute; top: -9px; left: 1.4rem; width: 18px; height: 18px; border-radius: 50%; background: var(--brand-500); border: 4px solid #fff; box-shadow: 0 0 0 1px var(--brand-200); }
.tl-no { font-family: var(--font-display); font-size: 1.5rem; font-weight: 700; color: var(--brand-200); }
.tl-item h3 { font-size: 1.1rem; margin: .3rem 0 .4rem; }
.tl-item p { font-size: .9rem; color: var(--text-soft); }

/* =========================================================
   COMPARE
   ========================================================= */
.compare { max-width: 900px; margin-inline: auto; background: #fff; border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow); }
.compare-head, .compare-row { display: grid; grid-template-columns: 1.2fr 1fr 1.3fr; gap: 1rem; align-items: center; padding: 1rem 1.4rem; }
.compare-head { background: var(--slate-50); font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--text-muted); border-bottom: 1px solid var(--border); }
.compare-head .hl { color: var(--brand-700); }
.compare-row { border-bottom: 1px solid var(--slate-100); font-size: .95rem; }
.compare-row:last-child { border-bottom: none; }
.compare-row > span:first-child { font-weight: 600; }
.compare-row .neg { color: var(--text-muted); }
.compare-row .pos { display: inline-flex; align-items: center; gap: .4rem; font-weight: 600; color: var(--brand-700); }
.compare-row .pos .icon { width: 17px; height: 17px; padding: 2px; background: var(--brand-50); border-radius: 50%; }

/* =========================================================
   USE CASES
   ========================================================= */
.usecase-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1.1rem; }
.uc-card { position: relative; overflow: hidden; padding: 1.6rem; border-radius: var(--radius); background: #fff; border: 1px solid var(--border); box-shadow: var(--shadow-sm);
  transition: transform .2s var(--ease), box-shadow .3s, border-color .2s; }
.uc-card::before { content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 4px; background: linear-gradient(var(--brand-400), var(--brand-600)); transform: scaleY(0); transform-origin: top; transition: transform .3s var(--ease); }
.uc-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--brand-200); }
.uc-card:hover::before { transform: scaleY(1); }
.uc-card h3 { font-size: 1.14rem; margin-bottom: .45rem; }
.uc-card p { font-size: .92rem; color: var(--text-soft); }

/* =========================================================
   MARQUEE
   ========================================================= */
.marquee-section { padding: clamp(40px,6vw,64px) 0; border-block: 1px solid var(--border); background: var(--slate-50); }
.marquee-label { text-align: center; font-size: .82rem; font-weight: 600; text-transform: uppercase; letter-spacing: .1em; color: var(--text-muted); margin-bottom: 2rem; }
.marquee { position: relative; overflow: hidden; -webkit-mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent); mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent); }
.marquee-track { display: flex; gap: 3rem; width: max-content; animation: marquee 32s linear infinite; }
.marquee:hover .marquee-track { animation-play-state: paused; }
.marquee-track span { font-family: var(--font-display); font-size: 1.05rem; font-weight: 600; color: var(--slate-500); white-space: nowrap; }
@keyframes marquee { to { transform: translateX(-50%); } }

/* =========================================================
   WHY VLABEL
   ========================================================= */
.why-layout { display: grid; grid-template-columns: 1fr 1.1fr; gap: clamp(2rem,4vw,3.5rem); align-items: center; }
.why-copy .btn { margin-top: 1.8rem; }
.why-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.why-card { position: relative; overflow: hidden; padding: 1.5rem; border-radius: var(--radius); background: #fff; border: 1px solid var(--border); box-shadow: var(--shadow-sm); transition: transform .2s var(--ease), box-shadow .3s; }
.why-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.w-ic { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; background: var(--brand-50); color: var(--brand-700); margin-bottom: .9rem; }
.w-ic .icon { width: 23px; height: 23px; }
.why-card h3 { font-size: 1.08rem; margin-bottom: .35rem; }
.why-card p { font-size: .9rem; color: var(--text-soft); }

/* =========================================================
   FAQ
   ========================================================= */
.faq-layout { display: grid; grid-template-columns: .85fr 1.15fr; gap: clamp(2rem,4vw,3.5rem); align-items: start; }
.faq-list { display: grid; gap: .8rem; }
.faq-item { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; transition: border-color .2s, box-shadow .25s; }
.faq-item[open] { border-color: var(--brand-200); box-shadow: var(--shadow); }
.faq-item summary { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1.15rem 1.35rem; font-weight: 600; font-size: 1rem; list-style: none; cursor: pointer; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-ic { width: 22px; height: 22px; color: var(--brand-600); flex: none; transition: transform .3s var(--ease); }
.faq-item[open] .faq-ic { transform: rotate(45deg); }
.faq-body { padding: 0 1.35rem 1.25rem; }
.faq-body p { color: var(--text-soft); font-size: .95rem; }

/* =========================================================
   CONTACT
   ========================================================= */
.contact-shell { display: grid; grid-template-columns: 1fr 1fr; border-radius: var(--radius-xl); overflow: hidden; box-shadow: var(--shadow-lg); border: 1px solid var(--border); }
.contact-info { padding: clamp(2rem, 4vw, 3.2rem); color: #fff; background: radial-gradient(120% 120% at 0% 0%, #16233d, var(--ink) 70%); }
.contact-info .section-title { font-size: clamp(1.5rem, 3vw, 2.1rem); }
.contact-info .section-lead { color: var(--slate-300); }
.contact-list { display: grid; gap: 1rem; margin-top: 1.8rem; }
.contact-list li { display: flex; align-items: flex-start; gap: .8rem; font-size: .93rem; color: var(--slate-200); }
.contact-list a:hover { color: var(--brand-300); }
.c-ic { width: 38px; height: 38px; border-radius: 10px; flex: none; display: grid; place-items: center; background: rgba(45,212,191,.12); color: var(--brand-300); }
.c-ic .icon { width: 19px; height: 19px; }

.contact-form { padding: clamp(2rem, 4vw, 3.2rem); background: #fff; display: grid; gap: 1rem; align-content: start; }
.field { display: grid; gap: .4rem; }
.field label { font-size: .85rem; font-weight: 600; color: var(--text-soft); }
.field input, .field textarea {
  width: 100%; padding: .8rem 1rem; border: 1.5px solid var(--slate-200); border-radius: var(--radius-sm);
  background: var(--slate-50); color: var(--text); transition: border-color .2s, background .2s, box-shadow .2s; resize: vertical;
}
.field input:focus, .field textarea:focus { outline: none; border-color: var(--brand-400); background: #fff; box-shadow: 0 0 0 4px rgba(20,184,166,.12); }
.field input.invalid, .field textarea.invalid { border-color: #ef4444; background: #fef2f2; }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; opacity: 0; }
.contact-form .btn { margin-top: .3rem; }
.form-note { font-size: .88rem; text-align: center; min-height: 1.2em; }
.form-note.ok { color: var(--brand-700); font-weight: 600; }
.form-note.err { color: #ef4444; font-weight: 600; }

/* =========================================================
   FOOTER
   ========================================================= */
.site-footer { background: var(--ink); color: var(--slate-300); padding-top: clamp(56px,7vw,80px); }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.4fr; gap: 2.4rem; padding-bottom: 3rem; }
.footer-brand .brand { margin-bottom: 1rem; }
.footer-brand .brand-name { color: #fff; }
.footer-brand p { font-size: .92rem; color: var(--slate-400); max-width: 42ch; }
.footer-slogan { margin-top: 1rem !important; color: var(--brand-300) !important; font-weight: 600; }
.footer-col h3 { font-size: .82rem; text-transform: uppercase; letter-spacing: .07em; color: #fff; margin-bottom: 1rem; }
.footer-col a { display: block; padding: .35rem 0; font-size: .92rem; color: var(--slate-400); transition: color .2s; }
.footer-col a:hover { color: var(--brand-300); }
.footer-contact p { display: flex; align-items: flex-start; gap: .55rem; font-size: .9rem; padding: .3rem 0; color: var(--slate-400); }
.footer-contact .icon { width: 18px; height: 18px; color: var(--brand-400); flex: none; margin-top: 2px; }
.footer-contact a:hover { color: var(--brand-300); }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: .6rem; padding: 1.5rem 0; border-top: 1px solid rgba(255,255,255,.09); font-size: .84rem; color: var(--slate-500); }

/* =========================================================
   SCROLL REVEAL
   ========================================================= */
[data-reveal] { opacity: 0; transform: translateY(26px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
[data-reveal].in { opacity: 1; transform: none; }
[data-reveal-delay="1"] { transition-delay: .08s; }
[data-reveal-delay="2"] { transition-delay: .16s; }
[data-reveal-delay="3"] { transition-delay: .24s; }
[data-reveal-delay="4"] { transition-delay: .32s; }
[data-reveal-delay="5"] { transition-delay: .4s; }

/* =========================================================
   RESPONSIVE
   Chiến lược: desktop → 1024 (tablet ngang) → 860 (tablet dọc)
   → 640 (mobile) → 420 (điện thoại nhỏ). Mobile-friendly:
   tap target ≥ 44px, không tràn ngang, chống zoom input iOS.
   ========================================================= */

/* ---- Tablet ngang ---- */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-visual { max-width: 440px; margin: .5rem auto 0; min-height: unset; }
  .hero-sub { max-width: 54ch; }
  .split-head { grid-template-columns: 1fr; align-items: start; }
  .prob-layout { grid-template-columns: 1fr; }
  .opp-card { position: static; }
  .legal-grid, .bento, .glass-grid, .usecase-grid { grid-template-columns: repeat(2,1fr); }
  .bento-lg { grid-row: auto; }
  .bento-wide { grid-column: span 2; }
  .tech-layout, .why-layout, .faq-layout { grid-template-columns: 1fr; }
  .why-grid { grid-template-columns: 1fr 1fr; }
  .timeline { grid-template-columns: repeat(2,1fr); }
  .timeline::before { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: span 2; }
  .tech-diagram { max-width: 380px; }
}

/* ---- Tablet dọc: chuyển sang menu mobile ---- */
@media (max-width: 860px) {
  .nav, .header-cta { display: none; }
  .nav-toggle { display: grid; }
  .site-header.menu-open { background: #fff; border-bottom-color: var(--border); }
  /* Chỉ hiện khi KHÔNG có thuộc tính hidden → nút toggle mới đóng/mở được */
  .mobile-nav:not([hidden]) { display: flex; }
  .header-inner { height: 64px; }
  .faq-layout .center-head { text-align: left; }
}

/* ---- Mobile ---- */
@media (max-width: 640px) {
  .section { padding: clamp(56px, 12vw, 76px) 0; }
  .center-head { margin-bottom: 40px; }

  /* Hero */
  .hero { padding-top: 40px; }
  .hero-title { letter-spacing: -.03em; }
  .hero-sub { max-width: 100%; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn { width: 100%; }
  .hero-visual { max-width: 340px; }
  .float-card { display: none; }

  /* Stat strip */
  .stat-strip { grid-template-columns: 1fr 1fr; gap: 1.4rem 1rem; padding: 1.4rem 1rem; }
  .stat + .stat::before { display: none; }

  /* Grids → 1 cột */
  .legal-grid, .bento, .glass-grid, .usecase-grid, .why-grid { grid-template-columns: 1fr; }
  .bento-wide { grid-column: auto; }

  /* Timeline dọc có đường nối */
  .timeline { grid-template-columns: 1fr; gap: 0; padding-left: 30px; position: relative; }
  .timeline::before { display: block; left: 9px; right: auto; top: 10px; bottom: 10px;
    width: 2px; height: auto; background: linear-gradient(var(--brand-300), var(--brand-500)); opacity: .55; }
  .tl-item { margin-bottom: 1rem; }
  .tl-item:last-child { margin-bottom: 0; }
  .tl-dot { left: -27px; top: 1.5rem; }

  /* Compare → thẻ xếp chồng, gắn nhãn cột */
  .contact-shell { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
  .footer-brand { grid-column: auto; }
  .compare-head { display: none; }
  .compare-row { grid-template-columns: 1fr; gap: .35rem; padding: 1.1rem 1.2rem; }
  .compare-row > span:first-child { font-weight: 700; color: var(--text); font-size: 1rem; }
  .compare-row .neg::before { content: "Nhãn vật lý — "; color: var(--text-muted); font-weight: 500; }
  .compare-row .pos { justify-content: flex-start; }

  /* Section-dark diagram gọn hơn */
  .tech-diagram { max-width: 320px; }
  .node { width: 84px; }
  .node span { font-size: .66rem; }
}

/* ---- Điện thoại nhỏ ---- */
@media (max-width: 420px) {
  .brand-tag { display: none; }
  .hero-badges { gap: .7rem 1.1rem; }
  .hero-badges li { font-size: .84rem; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  .btn-lg { padding: .9rem 1.3rem; }
  .eyebrow { font-size: .72rem; }
  .stat-num { font-size: 1.9rem; }
  .qr-device { padding: 1.1rem; }
}

/* ---- Chống zoom input trên iOS (font ≥ 16px) & tap highlight ---- */
@media (max-width: 860px) {
  .field input, .field textarea { font-size: 16px; }
  a, button, summary, .btn { -webkit-tap-highlight-color: rgba(20,184,166,.15); }
  .btn, .nav-toggle, .mobile-nav a, .faq-item summary { min-height: 44px; }
}

/* =========================================================
   REDUCED MOTION
   ========================================================= */
@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; scroll-behavior: auto !important; }
  [data-reveal] { opacity: 1 !important; transform: none !important; }
  .scan-line, .mesh, .marquee-track, .pulse-line, .node:not(.node-center) { animation: none !important; }
}