/* ===========================================================
   NNA ADS — Design System (Dark + NEON Green)
   Palette đồng bộ với Ad Scanner. Hiệu ứng: glow, gradient,
   3D float, scroll-reveal, button shine, ambient FX.
   =========================================================== */

:root{
  --bg-0:#04120b;
  --bg-1:#06180e;
  --bg-2:#0a2014;
  --surface: rgba(255,255,255,.04);
  --surface-2: rgba(255,255,255,.07);
  --border: rgba(64,210,138,.16);
  --border-2: rgba(64,210,138,.34);
  --border-glow: rgba(67,240,138,.5);

  --text:#e8f7ee;
  --muted:#8fb6a1;
  --muted-2:#5f8772;

  --neon:#43f08a;
  --neon-2:#9bffc0;
  --emerald:#43f08a;
  --green:#43f08a;
  --green-2:#16c172;
  --green-d:#0d8f53;

  --grad: linear-gradient(135deg,#16c172 0%,#43f08a 100%);
  --grad-bright: linear-gradient(135deg,#9bffc0 0%,#16c172 100%);
  --grad-text: linear-gradient(120deg,#9bffc0,#16c172 60%,#0d8f53);
  --grad-warm: linear-gradient(120deg,#43f08a,#9bffc0);

  --glow: 0 0 0 1px rgba(67,240,138,.25), 0 18px 50px -12px rgba(22,193,114,.5);
  --radius: 18px;
  --radius-sm: 12px;
  --container: 1200px;
  --ease: cubic-bezier(.22,.61,.36,1);
  --mono:ui-monospace,'Cascadia Code','SFMono-Regular','Courier New',monospace;
  --font: "Plus Jakarta Sans","Be Vietnam Pro",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  color:var(--text);
  background:var(--bg-0);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
ul{list-style:none}

/* Ambient page background: animated radial glows + grid */
body::before{
  content:"";position:fixed;inset:-25%;z-index:-2;pointer-events:none;
  background:
    radial-gradient(40% 35% at 16% 10%, rgba(22,193,114,.22), transparent 70%),
    radial-gradient(45% 40% at 86% 6%, rgba(67,240,138,.15), transparent 70%),
    radial-gradient(50% 50% at 72% 96%, rgba(16,150,90,.18), transparent 70%);
  animation:drift 24s ease-in-out infinite alternate;
}
@keyframes drift{0%{transform:translate(0,0) rotate(0deg)}100%{transform:translate(-3%,2%) rotate(5deg)}}
body::after{
  content:"";position:fixed;inset:0;z-index:-3;opacity:.22;pointer-events:none;
  background-image:
    linear-gradient(rgba(64,210,138,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(64,210,138,.05) 1px,transparent 1px);
  background-size:46px 46px;
  -webkit-mask-image:radial-gradient(circle at 50% 28%,#000,transparent 80%);
          mask-image:radial-gradient(circle at 50% 28%,#000,transparent 80%);
}
.neon-grid{position:fixed;inset:0;z-index:-2;pointer-events:none;
  -webkit-mask-image:radial-gradient(120% 100% at 50% 30%,#000 55%,transparent 92%);
          mask-image:radial-gradient(120% 100% at 50% 30%,#000 55%,transparent 92%)}
/* floating particle FX layer (injected via JS) */
.fx-layer{position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden}
.fx-dot{position:absolute;border-radius:50%;background:var(--neon);opacity:.0;
  box-shadow:0 0 12px var(--neon);animation:rise linear infinite}
@keyframes rise{
  0%{transform:translateY(20px) scale(.6);opacity:0}
  15%{opacity:.5}
  85%{opacity:.4}
  100%{transform:translateY(-120px) scale(1);opacity:0}
}

.container{width:100%;max-width:var(--container);margin:0 auto;padding:0 24px}

/* ============ TYPOGRAPHY ============ */
h1,h2,h3,h4{line-height:1.15;font-weight:800;letter-spacing:-.02em}
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--mono);font-size:11px;font-weight:700;letter-spacing:.18em;text-transform:uppercase;
  color:var(--neon);
}
.eyebrow::before{content:"";width:26px;height:2px;border-radius:2px;background:var(--grad)}
.grad-text{
  background:var(--grad-text);-webkit-background-clip:text;background-clip:text;color:transparent;
}
.section-title{font-size:clamp(28px,4vw,46px)}
.lead{color:var(--muted);font-size:clamp(15px,1.5vw,18px);max-width:62ch}

/* ============ BUTTONS ============ */
.btn{
  position:relative;display:inline-flex;align-items:center;gap:10px;
  padding:13px 24px;border-radius:999px;font-weight:800;font-size:15px;
  cursor:pointer;border:1px solid transparent;transition:.3s var(--ease);
  white-space:nowrap;overflow:hidden;
}
/* cream/white shine sweep */
.btn-primary,.cbtn,.scanbtn{position:relative;overflow:hidden}
.btn-primary::after,.cbtn::after{
  content:"";position:absolute;top:0;left:-130%;width:60%;height:100%;
  background:linear-gradient(100deg,transparent,rgba(255,255,255,.55),transparent);
  transform:skewX(-18deg);transition:left .6s var(--ease);
}
.btn-primary:hover::after,.cbtn:hover::after{left:140%}
.btn-primary{
  color:#03130a;background:var(--grad-bright);
  box-shadow:0 10px 30px -8px rgba(67,240,138,.55), 0 0 22px rgba(67,240,138,.35);
}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 42px -8px rgba(67,240,138,.7)}
.btn-ghost{
  color:var(--text);border-color:var(--border-2);background:var(--surface);
  backdrop-filter:blur(8px);
}
.btn-ghost:hover{border-color:var(--border-glow);color:var(--neon);transform:translateY(-2px)}
.btn-arrow{color:var(--neon);font-weight:700}
.btn-arrow .a{transition:.3s var(--ease)}
.btn-arrow:hover .a{transform:translateX(6px)}

/* ============ BRAND GLYPH (real platform logos) ============ */
.brand-glyph{display:grid;place-items:center;border-radius:10px;overflow:hidden;flex:none;
  background:#fff;}
.brand-glyph.dark{background:#000}
.brand-glyph svg{width:78%;height:78%;display:block}

/* ============ TOP BAR ============ */
.topbar{
  font-size:12.5px;color:var(--muted);font-family:var(--mono);
  border-bottom:1px solid var(--border);
  background:linear-gradient(90deg,rgba(22,193,114,.07),rgba(67,240,138,.04));
}
.topbar .container{display:flex;gap:22px;flex-wrap:nowrap;align-items:center;min-height:40px;overflow:hidden;white-space:nowrap}
.topbar .ti{display:inline-flex;align-items:center;gap:8px}
.topbar .ti svg{width:15px;height:15px;color:var(--neon);flex:none}
.topbar .spacer{margin-left:auto}

/* ============ HEADER / NAV ============ */
.site-header{position:sticky;top:0;z-index:60;transition:.35s var(--ease)}
.site-header.scrolled .navbar{
  background:rgba(6,24,14,.86);backdrop-filter:blur(16px);
  border-bottom-color:var(--border-2);
  box-shadow:0 10px 40px -20px rgba(0,0,0,.85);
}
.navbar{border-bottom:1px solid transparent;transition:.35s var(--ease)}
.navbar .container{display:flex;align-items:center;gap:14px;height:74px}

/* logo */
.brand{display:flex;align-items:center;gap:12px}
.logo-badge{
  position:relative;width:50px;height:50px;border-radius:13px;flex:none;background:#000;overflow:hidden;
  border:1px solid var(--border-2);box-shadow:0 0 0 1px rgba(0,0,0,.4),0 6px 18px rgba(18,140,82,.45);
}
.logo-badge svg{position:absolute;inset:0;width:100%;height:100%}
.logo-badge img{position:absolute;inset:0;width:100%;height:100%;object-fit:contain}
.brand .bt{display:flex;flex-direction:column;line-height:1.1}
.brand .bt b{font-size:18px;font-weight:900;letter-spacing:.3px;
  background:var(--grad-bright);-webkit-background-clip:text;background-clip:text;color:transparent}
.brand .bt small{font-family:var(--mono);font-size:9.5px;letter-spacing:.22em;color:var(--muted-2);font-weight:600;margin-top:3px}

/* one-line desktop nav — gọn 1 dòng, mỗi tab có hiệu ứng riêng */
.nav{margin-left:auto;display:flex;align-items:center;gap:1px;flex-wrap:nowrap}
.nav a.nav-link{
  position:relative;padding:9px 11px;border-radius:10px;font-weight:600;font-size:14px;
  color:var(--text);transition:color .25s var(--ease),transform .25s var(--ease),background .25s var(--ease);
  display:inline-flex;align-items:center;gap:5px;white-space:nowrap;
}
.nav a.nav-link::after{
  content:"";position:absolute;left:11px;right:11px;bottom:4px;height:2px;border-radius:2px;
  background:var(--grad-bright);transform:scaleX(0);transform-origin:center;
  transition:transform .3s var(--ease);opacity:.95;
}
.nav a.nav-link:hover{color:var(--neon);transform:translateY(-2px)}
.nav a.nav-link:hover::after{transform:scaleX(1)}
.nav a.nav-link.active{color:var(--neon)}
.nav a.nav-link.active::after{transform:scaleX(1)}
.nav a.nav-link.scan{color:var(--neon);border:1px solid var(--border-2);background:rgba(67,240,138,.08);}
.nav a.nav-link.scan::after{display:none}
.nav a.nav-link.scan:hover{background:rgba(67,240,138,.18);box-shadow:0 0 16px rgba(67,240,138,.35);transform:translateY(-2px)}
.nav a.nav-link.scan .blip{width:7px;height:7px;border-radius:50%;background:var(--neon);box-shadow:0 0 8px var(--neon);animation:pulse 1.6s infinite}
@keyframes pulse{0%,100%{opacity:1;transform:scale(1)}50%{opacity:.4;transform:scale(.7)}}
.nav .caret{width:13px;height:13px;transition:.25s}
.has-drop{position:relative}
.has-drop:hover .caret{transform:rotate(180deg)}
.dropdown{
  position:absolute;top:calc(100% + 10px);left:50%;transform:translate(-50%,8px);
  min-width:262px;background:rgba(7,21,14,.97);backdrop-filter:blur(18px);
  border:1px solid var(--border-2);border-radius:16px;padding:10px;
  box-shadow:0 30px 60px -20px rgba(0,0,0,.85);
  opacity:0;visibility:hidden;transition:.28s var(--ease);
}
.has-drop:hover .dropdown{opacity:1;visibility:visible;transform:translate(-50%,0)}
.dropdown a{
  display:flex;align-items:center;gap:12px;padding:10px 12px;border-radius:11px;
  font-weight:600;font-size:14.5px;color:var(--muted);transition:.2s;
}
.dropdown a:hover{background:var(--surface-2);color:var(--text)}
.dropdown a .brand-glyph{width:34px;height:34px}

.nav-cta{margin-left:6px;padding:10px 16px;font-size:14px;flex:none}
.hamburger{display:none;width:46px;height:46px;border-radius:12px;border:1px solid var(--border-2);
  background:var(--surface);color:var(--text);cursor:pointer;align-items:center;justify-content:center;margin-left:auto;
  transition:.25s var(--ease)}
.hamburger:hover{border-color:var(--border-glow);color:var(--neon);box-shadow:0 0 16px rgba(67,240,138,.3)}
.hamburger svg{width:22px;height:22px}

/* mobile drawer */
.mobile-nav{
  position:fixed;inset:0;z-index:80;background:rgba(4,18,11,.98);backdrop-filter:blur(10px);
  transform:translateX(100%);transition:.35s var(--ease);padding:22px;overflow-y:auto;
  -webkit-overflow-scrolling:touch;
}
.mobile-nav.open{transform:translateX(0)}
.mobile-nav .mh{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;
  position:sticky;top:-22px;background:rgba(4,18,11,.98);padding:10px 0;z-index:2}
.mobile-nav .close{width:46px;height:46px;border-radius:12px;border:1px solid var(--border-2);background:var(--surface);color:#fff;font-size:22px;cursor:pointer;transition:.25s}
.mobile-nav .close:active{transform:scale(.92)}
.mobile-nav a{position:relative;display:block;padding:15px 14px;font-size:17px;font-weight:600;
  border-bottom:1px solid var(--border);border-radius:10px;transition:.25s var(--ease)}
.mobile-nav>a:active,.mobile-nav .sub a:active{background:rgba(67,240,138,.1)}
.mobile-nav>a::before{content:"";position:absolute;left:0;top:50%;transform:translateY(-50%) scaleY(0);
  width:3px;height:60%;border-radius:3px;background:var(--grad-bright);transition:transform .25s var(--ease)}
.mobile-nav>a:hover{color:var(--neon);padding-left:20px}
.mobile-nav>a:hover::before{transform:translateY(-50%) scaleY(1)}
.mobile-nav .sub{margin:2px 0 6px 10px;border-left:2px solid var(--border);padding-left:6px}
.mobile-nav .sub a{font-size:14.5px;color:var(--muted);padding:11px 14px;border-bottom:none}
.mobile-nav .sub a:hover{color:var(--neon)}

/* ============ SECTION ============ */
.section{padding:clamp(60px,8vw,110px) 0;position:relative}
.section-head{max-width:720px;margin-bottom:50px}
.section-head .section-title{margin:14px 0 16px}
.center{text-align:center;margin-left:auto;margin-right:auto}
.center .lead{margin-left:auto;margin-right:auto}
.accent-line{height:3px;width:120px;border-radius:3px;background:var(--grad-bright);background-size:200% 100%;animation:flow 3s linear infinite;margin:22px 0}
.center .accent-line{margin-left:auto;margin-right:auto}
@keyframes flow{to{background-position:200% 0}}

/* ============ HERO ============ */
.hero{position:relative;padding:clamp(56px,8vw,100px) 0 clamp(64px,8vw,110px);overflow:hidden}
.hero .container{display:grid;grid-template-columns:1.05fr .95fr;gap:40px;align-items:center}
.hero h1{font-size:clamp(34px,5.4vw,64px);line-height:1.05}
.hero p.lead{margin:22px 0 30px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;align-items:center}
.hero-tags{display:flex;gap:10px;flex-wrap:wrap;margin-top:30px}
.hero-tags span{
  font-size:13px;font-weight:600;color:var(--muted);padding:8px 14px;border-radius:999px;
  border:1px solid var(--border);background:var(--surface);display:inline-flex;align-items:center;gap:8px;
}

/* hero visual: floating platform logos around a core */
.hero-visual{position:relative;height:480px}
.orb-core{
  position:absolute;top:50%;left:50%;width:190px;height:190px;transform:translate(-50%,-50%);
  border-radius:50%;
  background:radial-gradient(circle at 35% 30%,#9bffc0,#16c172 45%,#063d22 100%);
  box-shadow:0 0 90px 10px rgba(67,240,138,.55),inset 0 0 60px rgba(0,0,0,.4);
  animation:bob 6s ease-in-out infinite;
}
.orb-core::after{
  content:"NNA";position:absolute;inset:0;display:grid;place-items:center;
  font-weight:900;font-size:36px;color:#03241d;letter-spacing:-1px;
}
.ring{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  border:1px dashed rgba(67,240,138,.28);border-radius:50%;animation:spin 26s linear infinite;
}
.ring.r1{width:330px;height:330px}
.ring.r2{width:460px;height:460px;animation-duration:40s;animation-direction:reverse;border-color:rgba(155,255,192,.18)}
@keyframes spin{to{transform:translate(-50%,-50%) rotate(360deg)}}

.chip{
  position:absolute;display:flex;align-items:center;gap:9px;padding:10px 15px;border-radius:15px;
  background:rgba(8,24,14,.88);border:1px solid var(--border-2);backdrop-filter:blur(10px);
  box-shadow:0 18px 40px -16px rgba(0,0,0,.7);font-weight:700;font-size:14px;
  animation:float 5s ease-in-out infinite;
}
.chip .brand-glyph{width:30px;height:30px}
.chip.c1{top:6%;left:2%;animation-delay:.2s}
.chip.c2{top:18%;right:0;animation-delay:1.1s}
.chip.c3{bottom:16%;left:-4%;animation-delay:.6s}
.chip.c4{bottom:4%;right:6%;animation-delay:1.6s}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-16px)}}
@keyframes bob{0%,100%{transform:translate(-50%,-50%) translateY(0)}50%{transform:translate(-50%,-50%) translateY(-14px)}}

/* ============ STATS ============ */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.stat{
  padding:26px;border-radius:var(--radius);background:var(--surface);border:1px solid var(--border);
  text-align:center;position:relative;overflow:hidden;
}
.stat:hover{border-color:var(--border-glow)}
.stat .num{font-size:clamp(30px,4vw,44px);font-weight:900;line-height:1;
  background:var(--grad-bright);-webkit-background-clip:text;background-clip:text;color:transparent}
.stat .lb{color:var(--muted);font-size:14px;margin-top:8px}

/* ============ GLASS CARD GRID ============ */
.grid{display:grid;gap:22px}
.g-3{grid-template-columns:repeat(3,1fr)}
.g-4{grid-template-columns:repeat(4,1fr)}
.g-2{grid-template-columns:repeat(2,1fr)}
.card{
  position:relative;padding:28px;border-radius:var(--radius);
  background:linear-gradient(165deg,rgba(13,38,25,.6),rgba(5,16,11,.7));border:1px solid var(--border);
  transition:.35s var(--ease);overflow:hidden;
}
.card::before{content:"";position:absolute;width:130px;height:130px;right:-40px;top:-40px;border-radius:50%;
  background:radial-gradient(circle,rgba(67,240,138,.18),transparent 70%);pointer-events:none;opacity:0;transition:.35s}
.card:hover{transform:translateY(-6px);border-color:var(--border-2);box-shadow:0 22px 48px rgba(0,0,0,.5),0 0 26px rgba(67,240,138,.18)}
.card:hover::before{opacity:1}
.card .c-ico{
  width:54px;height:54px;border-radius:14px;display:grid;place-items:center;font-size:24px;
  background:linear-gradient(135deg,rgba(67,240,138,.2),rgba(22,193,114,.14));
  border:1px solid var(--border-2);margin-bottom:18px;
}
.card h3{font-size:20px;margin-bottom:10px}
.card p{color:var(--muted);font-size:14.5px}

/* ============ COURSE TABS ============ */
.tabs-wrap{display:grid;grid-template-columns:300px 1fr;gap:28px;align-items:start}
.tab-list{display:flex;flex-direction:column;gap:8px}
.tab-btn{
  text-align:left;padding:14px 16px;border-radius:14px;font-weight:700;font-size:15.5px;
  color:var(--muted);background:transparent;border:1px solid transparent;cursor:pointer;transition:.28s var(--ease);
  display:flex;align-items:center;gap:12px;
}
.tab-btn .brand-glyph{width:36px;height:36px}
.tab-btn:hover{color:var(--text);background:var(--surface)}
.tab-btn.active{color:#03130a;background:var(--grad-bright);box-shadow:var(--glow)}
.tab-panels{position:relative}
.tab-panel{
  display:none;padding:34px;border-radius:var(--radius);
  background:linear-gradient(180deg,rgba(255,255,255,.05),rgba(255,255,255,.02));
  border:1px solid var(--border);animation:fadeUp .5s var(--ease);
}
.tab-panel.active{display:block}
.tab-panel h3{font-size:clamp(22px,2.6vw,30px);margin-bottom:14px}
.tab-panel .feats{display:grid;gap:12px;margin:20px 0 26px}
.tab-panel .feats li{display:flex;gap:12px;color:var(--muted);font-size:15px}
.tab-panel .feats li::before{content:"";width:8px;height:8px;border-radius:50%;margin-top:9px;background:var(--grad-bright);flex:none}
.panel-meta{display:flex;gap:24px;flex-wrap:wrap;margin-bottom:22px}
.panel-meta .pm{font-size:13px;color:var(--muted)}
.panel-meta .pm b{display:block;color:var(--text);font-size:18px}

/* ============ STEPS / ROADMAP ============ */
.steps{position:relative;display:grid;gap:0}
.step{
  display:grid;grid-template-columns:64px 1fr;gap:20px;padding:22px 0;
  border-bottom:1px solid var(--border);align-items:start;
}
.step:last-child{border-bottom:0}
.step .sn{
  width:54px;height:54px;border-radius:14px;display:grid;place-items:center;font-weight:900;font-size:20px;
  color:var(--neon);background:var(--surface);border:1px solid var(--border-2);
}
.step h4{font-size:18px;margin-bottom:6px}
.step p{color:var(--muted);font-size:14.5px}

/* ============ SPLIT / MEDIA ============ */
.split{display:grid;grid-template-columns:1fr 1fr;gap:46px;align-items:center}
.media-card{
  position:relative;border-radius:24px;padding:30px;min-height:360px;overflow:hidden;
  background:
    radial-gradient(120% 80% at 80% 10%,rgba(67,240,138,.25),transparent 60%),
    radial-gradient(100% 80% at 10% 90%,rgba(22,193,114,.25),transparent 60%),
    linear-gradient(160deg,#0b231c,#06140f);
  border:1px solid var(--border-2);display:flex;align-items:flex-end;
}
.media-card .beam{position:absolute;inset:0;background:
  conic-gradient(from 180deg at 70% 30%,transparent,rgba(155,255,192,.18),transparent 30%);
  animation:spin 18s linear infinite}
.media-card .play{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  width:78px;height:78px;border-radius:50%;display:grid;place-items:center;
  background:var(--grad-bright);color:#03130a;box-shadow:var(--glow);cursor:pointer;
  animation:pulseRing 2.6s ease-out infinite;
}
@keyframes pulseRing{0%{box-shadow:0 0 0 0 rgba(67,240,138,.5)}70%{box-shadow:0 0 0 26px rgba(67,240,138,0)}100%{box-shadow:0 0 0 0 rgba(67,240,138,0)}}
.check-list{display:grid;gap:16px;margin-top:24px}
.check-list li{display:flex;gap:14px;align-items:flex-start}
.check-list .ck{width:26px;height:26px;border-radius:8px;display:grid;place-items:center;flex:none;background:var(--grad-bright);color:#03130a;font-weight:900;font-size:14px}
.check-list b{display:block}
.check-list span{color:var(--muted);font-size:14.5px}

/* ============ TEACHING (video + ảnh thực chiến) — inject mọi trang ============ */
.teach{padding:clamp(56px,7vw,96px) 0;position:relative}
.teach .wrap{display:grid;grid-template-columns:1.15fr .85fr;gap:34px;align-items:stretch}
.teach .video{
  position:relative;border-radius:22px;overflow:hidden;min-height:340px;
  background-size:cover;background-position:center;
  border:1px solid var(--border-2);box-shadow:0 22px 60px -20px rgba(0,0,0,.7);
}
.teach .video::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(4,18,11,.2),rgba(4,18,11,.85))}
.teach .video .lbl{position:absolute;left:22px;bottom:20px;z-index:2}
.teach .video .lbl .t{font-size:22px;font-weight:900}
.teach .video .lbl .s{color:var(--muted);font-size:13px;margin-top:4px}
.teach .video .live{position:absolute;left:18px;top:18px;z-index:2;display:inline-flex;align-items:center;gap:7px;
  font-family:var(--mono);font-size:11px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--neon);
  padding:6px 12px;border-radius:999px;background:rgba(4,18,11,.6);border:1px solid var(--border-2)}
.teach .video .live .blip{width:7px;height:7px;border-radius:50%;background:var(--neon);box-shadow:0 0 8px var(--neon);animation:pulse 1.4s infinite}
.teach .video .play{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);z-index:2;
  width:74px;height:74px;border-radius:50%;display:grid;place-items:center;cursor:pointer;
  background:var(--grad-bright);color:#03130a;font-size:24px;box-shadow:var(--glow);animation:pulseRing 2.6s ease-out infinite}
.teach .gallery{display:grid;grid-template-columns:1fr 1fr;grid-template-rows:1fr 1fr;gap:14px}
.teach .gallery .ph{border-radius:16px;background-size:cover;background-position:center;border:1px solid var(--border);position:relative;overflow:hidden;min-height:110px}
.teach .gallery .ph::after{content:attr(data-cap);position:absolute;left:10px;bottom:8px;font-size:11.5px;font-weight:700;color:#eafff2;text-shadow:0 1px 4px rgba(0,0,0,.8)}
.teach .gallery .ph.big{grid-column:1 / span 2}

/* ============ CAROUSEL ============ */
.carousel{position:relative}
.carousel-head{display:flex;justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:30px}
.carousel-nav{display:flex;gap:12px}
.cbtn{width:52px;height:52px;border-radius:50%;border:1px solid var(--border-2);background:var(--surface);
  color:var(--text);cursor:pointer;display:grid;place-items:center;transition:.25s}
.cbtn:hover{border-color:var(--border-glow);color:var(--neon);transform:translateY(-2px)}
.track-wrap{overflow:hidden}
.track{display:flex;gap:22px;transition:transform .5s var(--ease)}
.slide{flex:0 0 calc((100% - 44px)/3);min-width:0}
.post{border-radius:var(--radius);overflow:hidden;background:var(--surface);border:1px solid var(--border);transition:.35s var(--ease)}
.post:hover{transform:translateY(-6px);border-color:var(--border-glow);box-shadow:0 0 24px rgba(67,240,138,.18)}
.post .thumb{height:190px;background-size:cover;background-position:center;position:relative}
.post .thumb::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent,rgba(4,18,11,.7))}
.post .pc{padding:20px}
.post .tag{font-size:12px;font-weight:700;color:var(--neon);text-transform:uppercase;letter-spacing:.08em}
.post h4{font-size:17px;margin:8px 0 0}

/* ============ TESTIMONIAL ============ */
.quote{padding:30px;border-radius:var(--radius);background:var(--surface);border:1px solid var(--border)}
.quote p{font-size:15.5px;color:var(--text);margin-bottom:18px}
.quote .who{display:flex;align-items:center;gap:12px}
.quote .av{width:46px;height:46px;border-radius:50%;background:var(--grad-bright);display:grid;place-items:center;font-weight:800;color:#03130a}
.quote .who b{display:block;font-size:14.5px}
.quote .who small{color:var(--muted)}

/* ============ CTA BAND ============ */
.cta-band{
  position:relative;border-radius:28px;padding:clamp(34px,5vw,64px);overflow:hidden;text-align:center;
  background:
    radial-gradient(80% 120% at 50% 0%,rgba(67,240,138,.25),transparent 60%),
    linear-gradient(160deg,#0c2a1c,#061812);
  border:1px solid var(--border-glow);
}
.cta-band h2{font-size:clamp(26px,4vw,42px);margin-bottom:14px}
.cta-band p{color:var(--muted);max-width:60ch;margin:0 auto 26px}
.cta-band .hero-cta{justify-content:center}

/* ============ PAGE HERO ============ */
.page-hero{padding:clamp(60px,7vw,100px) 0 clamp(36px,4vw,60px);text-align:center;position:relative}
.page-hero h1{font-size:clamp(32px,5vw,56px)}
.breadcrumb{display:flex;gap:10px;justify-content:center;color:var(--muted);font-size:14px;margin-top:18px}
.breadcrumb a:hover{color:var(--neon)}
.breadcrumb .sep{opacity:.5}

/* ============ FAQ ============ */
.faq{display:grid;gap:14px;max-width:860px;margin:0 auto}
.faq.two-col{max-width:none;grid-template-columns:1fr 1fr}
.faq-item{border:1px solid var(--border);border-radius:14px;background:var(--surface);overflow:hidden;align-self:start}
.faq-q{width:100%;text-align:left;padding:18px 20px;background:transparent;color:var(--text);
  font-weight:700;font-size:15.5px;cursor:pointer;display:flex;justify-content:space-between;gap:16px;align-items:center}
.faq-q .pm{transition:.3s;color:var(--neon);font-size:22px;flex:none}
.faq-item.open{border-color:var(--border-2)}
.faq-item.open .faq-q .pm{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .4s var(--ease);color:var(--muted)}
.faq-a p{padding:0 20px 18px;font-size:14.5px}

/* ============ CONTACT ============ */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:34px}
.field{margin-bottom:16px}
.field label{display:block;font-size:13.5px;font-weight:600;margin-bottom:7px;color:var(--muted)}
.field input,.field textarea,.field select{
  width:100%;padding:13px 15px;border-radius:12px;background:rgba(3,12,8,.6);
  border:1px solid var(--border);color:var(--text);font-family:inherit;font-size:15px;transition:.2s;
}
.field input:focus,.field textarea:focus,.field select:focus{outline:none;border-color:var(--neon);box-shadow:0 0 0 3px rgba(67,240,138,.16)}
.contact-info li{display:flex;gap:14px;align-items:flex-start;padding:16px 0;border-bottom:1px solid var(--border)}
.contact-info .ci{width:46px;height:46px;border-radius:12px;display:grid;place-items:center;background:var(--surface);border:1px solid var(--border-2);color:var(--neon);flex:none}
.map-embed{margin-top:22px;border-radius:16px;overflow:hidden;border:1px solid var(--border);height:240px}
.map-embed iframe{width:100%;height:100%;border:0;filter:grayscale(.3) invert(.9) hue-rotate(90deg)}

/* ============ PRICING ============ */
.price{padding:30px;border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);position:relative}
.price.feat{border-color:var(--border-glow);background:linear-gradient(180deg,rgba(67,240,138,.08),rgba(255,255,255,.02))}
.price .badge{position:absolute;top:-12px;left:50%;transform:translateX(-50%);background:var(--grad-bright);color:#03130a;font-size:12px;font-weight:800;padding:5px 14px;border-radius:999px}
.price .amt{font-size:34px;font-weight:900;margin:10px 0}
.price .amt small{font-size:14px;color:var(--muted);font-weight:600}
.price ul{display:grid;gap:11px;margin:18px 0 24px}
.price ul li{display:flex;gap:10px;color:var(--muted);font-size:14.5px}
.price ul li::before{content:"✓";color:var(--neon);font-weight:900}

/* ============ DOC LIST ============ */
.doc{display:flex;gap:16px;align-items:center;padding:18px;border-radius:14px;background:var(--surface);border:1px solid var(--border);transition:.3s}
.doc:hover{border-color:var(--border-glow);transform:translateX(4px)}
.doc .dic{width:48px;height:48px;border-radius:12px;display:grid;place-items:center;background:linear-gradient(135deg,rgba(67,240,138,.2),rgba(22,193,114,.14));font-size:22px;flex:none}
.doc h4{font-size:16px}
.doc small{color:var(--muted)}
.doc .dl{margin-left:auto;color:var(--neon);font-weight:700;font-size:14px}

/* ============ FOOTER ============ */
.site-footer{border-top:1px solid var(--border);margin-top:30px;background:linear-gradient(180deg,transparent,rgba(22,193,114,.06))}
.footer-top{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:34px;padding:62px 0 40px}
.footer-brand p{color:var(--muted);font-size:14.5px;margin:16px 0}
.footer-col h5{font-size:15px;margin-bottom:16px}
.footer-col a{display:block;color:var(--muted);font-size:14.5px;padding:7px 0;transition:.2s}
.footer-col a:hover{color:var(--neon);transform:translateX(3px)}
.footer-divider{height:1px;background:linear-gradient(90deg,transparent,var(--border-glow),transparent)}
.footer-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:14px;padding:22px 0;color:var(--muted);font-size:13.5px}
.footer-bottom .socials{display:flex;gap:12px}
.footer-bottom .socials a{width:38px;height:38px;border-radius:10px;border:1px solid var(--border-2);display:grid;place-items:center;transition:.25s}
.footer-bottom .socials a:hover{border-color:var(--border-glow);color:var(--neon)}

/* back to top + zalo bubble */
.to-top{position:fixed;right:24px;bottom:24px;width:50px;height:50px;border-radius:14px;border:none;
  background:var(--grad-bright);color:#03130a;cursor:pointer;display:grid;place-items:center;z-index:50;
  opacity:0;transform:translateY(20px) scale(.8);transition:.35s var(--ease);box-shadow:var(--glow)}
.to-top.show{opacity:1;transform:none}
.float-zalo{position:fixed;right:24px;bottom:86px;width:54px;height:54px;border-radius:50%;
  background:#0068ff;display:grid;place-items:center;color:#fff;font-weight:800;font-size:13px;z-index:50;
  box-shadow:0 12px 30px -8px rgba(0,104,255,.6);animation:bob2 4s ease-in-out infinite}
@keyframes bob2{0%,100%{transform:translateY(0)}50%{transform:translateY(-8px)}}

/* ============ SCROLL REVEAL ============ */
.reveal{opacity:0;transform:translateY(30px);transition:.7s var(--ease)}
.reveal.in{opacity:1;transform:none}
.reveal.d1{transition-delay:.08s}
.reveal.d2{transition-delay:.16s}
.reveal.d3{transition-delay:.24s}
.reveal.d4{transition-delay:.32s}
@keyframes fadeUp{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:none}}

/* ============ INSTRUCTOR BANNER ============ */
.instructor{display:grid;grid-template-columns:.85fr 1.15fr;gap:40px;align-items:center;
  border-radius:28px;padding:34px;position:relative;overflow:hidden;
  background:radial-gradient(90% 120% at 0% 0%,rgba(67,240,138,.14),transparent 60%),linear-gradient(160deg,#0b231c,#06140f);
  border:1px solid var(--border-2)}
.ins-photo{position:relative;border-radius:20px;overflow:hidden;min-height:380px;
  background:linear-gradient(160deg,#0e2a1e,#06140f);border:1px solid var(--border);display:grid;place-items:center}
.ins-photo img{width:100%;height:100%;object-fit:cover;object-position:top center}
.ins-ph-fallback{display:none;color:var(--muted-2);font-weight:700;text-align:center;font-size:14px;padding:20px}
.ins-ph-fallback small{font-family:var(--mono);font-size:11px;opacity:.7;display:block;margin-top:6px}
.ins-photo.noimg .ins-ph-fallback{display:block}
.ins-badge{position:absolute;left:16px;bottom:16px;z-index:2;font-size:12.5px;font-weight:800;color:#03130a;
  background:var(--grad-bright);padding:8px 14px;border-radius:999px;box-shadow:var(--glow)}
.ins-info .section-title{font-size:clamp(26px,3.4vw,40px)}
@media(max-width:880px){.instructor{grid-template-columns:1fr}.ins-photo{min-height:340px}}

/* ============ YOUTUBE LIGHTBOX ============ */
.yt-modal{position:fixed;inset:0;z-index:120;background:rgba(2,10,7,.86);backdrop-filter:blur(6px);
  display:grid;place-items:center;padding:24px;opacity:0;visibility:hidden;transition:.3s var(--ease)}
.yt-modal.open{opacity:1;visibility:visible}
.yt-box{position:relative;width:min(960px,100%)}
.yt-frame{position:relative;width:100%;aspect-ratio:16/9;border-radius:16px;overflow:hidden;border:1px solid var(--border-2);box-shadow:0 30px 80px -20px rgba(0,0,0,.8)}
.yt-frame iframe{position:absolute;inset:0;width:100%;height:100%}
.yt-close{position:absolute;top:-46px;right:0;width:40px;height:40px;border-radius:10px;border:1px solid var(--border-2);
  background:var(--surface);color:#fff;font-size:24px;cursor:pointer;line-height:1}
.yt-close:hover{border-color:var(--border-glow);color:var(--neon)}

/* ============ VIDEO THUMBNAIL (YouTube) ============ */
.media-card.video-card{cursor:pointer}
.media-card .yt-thumb{position:absolute;inset:0;z-index:0;background-size:cover;background-position:center;opacity:.55;transition:.3s var(--ease)}
.media-card .play{z-index:3}
.media-card.video-card:hover .yt-thumb{opacity:.72}

/* teach photos (gallery + strip) */
.teach .ph{position:relative;overflow:hidden;border-radius:16px;border:1px solid var(--border);min-height:120px;background-size:cover;background-position:center}
.teach .ph img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:center;z-index:1}
.teach .ph::before{content:"";position:absolute;inset:0;z-index:2;background:linear-gradient(180deg,transparent 45%,rgba(4,16,11,.85));pointer-events:none}
.teach .ph::after{content:attr(data-cap);position:absolute;left:12px;right:12px;bottom:9px;z-index:3;font-size:11.5px;font-weight:700;color:#eafff2;text-shadow:0 1px 4px rgba(0,0,0,.85)}
.teach .gallery{grid-template-columns:1fr 1fr;grid-template-rows:1fr 1fr}
.teach .gallery .ph.big{grid-column:auto}
.teach-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-top:14px}
@media(max-width:680px){.teach-strip{grid-template-columns:1fr 1fr}}

/* ============ FACEBOOK COURSE BANNER + GIFTS ============ */
.fb-banner{display:grid;grid-template-columns:.9fr 1.1fr;gap:36px;align-items:center;border-radius:28px;padding:30px;position:relative;overflow:hidden;
  background:radial-gradient(90% 120% at 100% 0%,rgba(24,119,242,.16),transparent 60%),radial-gradient(80% 120% at 0% 100%,rgba(67,240,138,.14),transparent 60%),linear-gradient(160deg,#0b231c,#06140f);
  border:1px solid var(--border-2)}
.fbb-media{position:relative;border-radius:20px;overflow:hidden;min-height:380px;display:grid;place-items:center;background:linear-gradient(160deg,#0e2a1e,#06140f);border:1px solid var(--border)}
.fbb-media img{width:100%;height:100%;object-fit:cover;object-position:top center}
.fbb-fallback{display:none;color:var(--muted-2);font-weight:700;text-align:center;font-size:14px;padding:20px}
.fbb-fallback small{display:block;font-family:var(--mono);font-size:11px;margin-top:6px;opacity:.7}
.fbb-media.noimg .fbb-fallback{display:block}
.fbb-gifts{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:20px 0 22px}
.gift{display:flex;gap:12px;align-items:flex-start;padding:15px;border-radius:14px;background:var(--surface);border:1px solid var(--border);transition:.3s var(--ease)}
.gift:hover{border-color:var(--border-glow);transform:translateY(-3px)}
.gift .gi{width:42px;height:42px;border-radius:11px;display:grid;place-items:center;font-size:20px;flex:none;background:linear-gradient(135deg,rgba(67,240,138,.2),rgba(22,193,114,.14));border:1px solid var(--border-2)}
.gift b{display:block;font-size:14.5px;margin-bottom:2px}
.gift span{color:var(--muted);font-size:12.5px;line-height:1.5}
@media(max-width:880px){.fb-banner{grid-template-columns:1fr}.fbb-gifts{grid-template-columns:1fr}}

.yt-box.portrait{width:min(420px,100%)}
.yt-box.portrait .yt-frame{aspect-ratio:9/16}
/* ============ RESPONSIVE ============ */
/* tighten one-line nav on smaller laptops trước khi gập */
@media(max-width:1280px){
  .nav{gap:0}
  .nav a.nav-link{padding:9px 9px;font-size:13.5px}
  .navbar .container{gap:10px}
}
@media(max-width:1180px){
  .nav a.nav-link{padding:8px 7.5px;font-size:13px}
  .nav-cta{padding:9px 13px;font-size:13px}
  .brand .bt small{display:none}
}
/* GẬP MENU thành hamburger sớm (≤1100px) để menu desktop luôn gọn 1 dòng */
@media(max-width:1100px){
  .nav,.nav-cta{display:none}
  .hamburger{display:flex}
  .topbar .spacer{display:none}
}
@media(max-width:980px){
  .hero .container{grid-template-columns:1fr}
  .hero-visual{height:380px;order:-1}
  .split,.contact-grid,.teach .wrap{grid-template-columns:1fr}
  .tabs-wrap{grid-template-columns:1fr}
  .tab-list{flex-direction:row;overflow-x:auto;padding-bottom:6px;-webkit-overflow-scrolling:touch}
  .tab-btn{white-space:nowrap}
  .stats{grid-template-columns:repeat(2,1fr)}
  .g-4{grid-template-columns:repeat(2,1fr)}
  .g-3{grid-template-columns:1fr 1fr}
  .footer-top{grid-template-columns:1fr 1fr}
  .slide{flex-basis:calc((100% - 22px)/2)}
  .faq.two-col{grid-template-columns:1fr}
}
@media(max-width:680px){
  .g-3,.g-2,.g-4,.stats,.footer-top{grid-template-columns:1fr}
  .slide{flex-basis:100%}
  .step{grid-template-columns:48px 1fr}
  .card[style*="grid-template-columns"]{grid-template-columns:1fr !important}
  .card[style*="grid-template-columns"] .thumb{min-height:180px !important}
  .card[style*="grid-template-columns"]>div:last-child{padding:24px !important}
  .to-top{right:16px;bottom:16px;width:46px;height:46px}
  .float-zalo{right:16px;bottom:72px;width:50px;height:50px}
}

/* ===== MOBILE OPTIMIZE — header gọn, topbar 1 dòng cuộn, thoáng nội dung ===== */
@media(max-width:1100px){
  .topbar{font-size:12px}
  .topbar .container{gap:16px;min-height:36px;overflow-x:auto}
}
@media(max-width:780px){
  .topbar{display:none !important}
  .navbar .container{height:58px;gap:10px}
  .logo-badge{width:40px;height:40px;border-radius:11px}
  .brand .bt b{font-size:15px}
  .brand .bt small{display:none}
  .hero{padding-top:22px}
  .page-hero{padding:28px 0 22px}
  .section{padding:42px 0}
  .hero-visual{height:300px}
  .hero-cta{width:100%}
  .hero-cta .btn{flex:1 1 auto;justify-content:center}
  .console{gap:16px}
  .panel{padding:16px}
  .fb-banner,.instructor{padding:18px;gap:20px}
  .fbb-media,.ins-photo{min-height:240px}
  .cta-band .hero-cta .btn{flex:1 1 auto;justify-content:center}
  .btn{padding:13px 18px}
  .footer-col a{padding:9px 0}
}
@media(max-width:560px){
  .container{padding:0 18px}
  .hero h1{font-size:30px}
  .section-title{font-size:25px}
  .teach .gallery{grid-template-columns:1fr 1fr}
  .hero-tags{gap:8px}
  .hero-tags span{font-size:12px;padding:7px 11px}
  .stat{padding:20px}
}

/* ============ ARTICLE / BLOG POST (auto-post) ============ */
.article-hero{padding:54px 0 10px}
.article-hero .meta-row{display:flex;gap:14px;flex-wrap:wrap;align-items:center;color:var(--muted);font-size:13.5px;margin-top:16px}
.article-hero .meta-row .tag{font-size:12px;font-weight:700;color:var(--neon);text-transform:uppercase;letter-spacing:.08em}
.article-hero h1{margin-top:14px;max-width:880px}
.article-wrap{max-width:780px;margin:0 auto}
.article{font-size:16.5px;line-height:1.85;color:var(--text)}
.article p{margin:0 0 20px}
.article h2{font-size:25px;margin:40px 0 16px;line-height:1.3}
.article h3{font-size:20px;margin:30px 0 12px}
.article ul,.article ol{margin:0 0 20px;padding-left:22px}
.article li{margin:0 0 10px;line-height:1.75}
.article strong{color:var(--neon)}
.article a{color:var(--neon);text-decoration:underline;text-underline-offset:3px}
.article blockquote{margin:26px 0;padding:18px 24px;border-left:3px solid var(--neon);
  background:rgba(67,240,138,.06);border-radius:0 12px 12px 0;color:var(--text);font-style:italic}
.article .lead{font-size:18.5px;color:var(--muted);margin-bottom:28px}
.article-cta{margin-top:48px}
.article-cover{height:300px;border-radius:var(--radius);background-size:cover;background-position:center;margin:8px 0 34px;position:relative;overflow:hidden}
.article-cover::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent,rgba(4,18,11,.45))}
@media(max-width:680px){.article-cover{height:200px}.article h2{font-size:22px}}

/* ============ HOVER SPOTLIGHT (vệt sáng theo con trỏ) ============ */
.has-spot{position:relative}
.has-spot::after{
  content:"";position:absolute;inset:0;z-index:1;pointer-events:none;border-radius:inherit;
  background:radial-gradient(220px circle at var(--mx,-100px) var(--my,-100px),rgba(67,240,138,.16),transparent 60%);
  opacity:0;transition:opacity .35s var(--ease);
}
.has-spot:hover::after{opacity:1}
.card>*,.quote>*,.price>*,.cta-band>*,.tab-panel>*{position:relative;z-index:2}

.btn:active{transform:translateY(0) scale(.97)}
.cbtn:active,.tab-btn:active{transform:scale(.96)}

/* ============ REDUCED MOTION ============ */
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.08s !important}
  .reveal{opacity:1 !important;transform:none !important}
}