:root{
    --ink:#171717; --ink-soft:#52525b; --bg:#fbfaf7; --surface:#ffffff;
    --border:rgba(23,23,23,0.10);
    --blue:#1e9be9; --blue-deep:#0f6fb8; --red:#ef3d3d; --red-deep:#c8262a;
    --amber:#f5a623;
    --radius:18px;
    --shadow: 0 1px 2px rgba(23,23,23,.04), 0 8px 24px -8px rgba(23,23,23,.12);
    --shadow-lg: 0 20px 60px -20px rgba(23,23,23,.25);
    color-scheme: light;
  }
  :root:not([data-theme="light"]){
    @media (prefers-color-scheme: dark){}
  }
  @media (prefers-color-scheme: dark){
    :root:not([data-theme="light"]){
      --ink:#f2f1ee; --ink-soft:#b7b5ad; --bg:#121210; --surface:#1a1a17;
      --border:rgba(242,241,238,0.10);
      --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px -8px rgba(0,0,0,.5);
      --shadow-lg: 0 20px 60px -20px rgba(0,0,0,.6);
    }
  }
  :root[data-theme="dark"]{
    --ink:#f2f1ee; --ink-soft:#b7b5ad; --bg:#121210; --surface:#1a1a17;
    --border:rgba(242,241,238,0.10);
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px -8px rgba(0,0,0,.5);
    --shadow-lg: 0 20px 60px -20px rgba(0,0,0,.6);
  }

  *{box-sizing:border-box}
  body{
    margin:0; background:var(--bg); color:var(--ink);
    font-family:'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    line-height:1.5; overflow-x:hidden;
  }
  h1,h2,h3,h4{font-family:'Fraunces', Georgia, serif; margin:0; letter-spacing:-0.01em}
  a{color:inherit; text-decoration:none}
  img{max-width:100%; display:block}
  section{position:relative}
  .container{max-width:1180px; margin:0 auto; padding-inline:24px}
  .eyebrow{
    display:inline-flex; align-items:center; gap:8px; font-size:12.5px; font-weight:700;
    letter-spacing:.08em; text-transform:uppercase; color:var(--blue-deep);
  }
  .eyebrow::before{content:"";width:16px;height:2px;background:var(--red);border-radius:2px}
  :root[data-theme="dark"] .eyebrow, @media (prefers-color-scheme: dark){:root:not([data-theme="light"]) .eyebrow{color:#6dc4ff}}

  /* ---------- reveal-on-scroll ---------- */
  .reveal{opacity:0; transform:translateY(28px); transition:opacity .7s cubic-bezier(.16,1,.3,1), transform .7s cubic-bezier(.16,1,.3,1)}
  .reveal.in{opacity:1; transform:none}
  .reveal-stagger > *{opacity:0; transform:translateY(24px); transition:opacity .6s cubic-bezier(.16,1,.3,1), transform .6s cubic-bezier(.16,1,.3,1)}
  .reveal-stagger.in > *{opacity:1; transform:none}
  .reveal-stagger.in > *:nth-child(1){transition-delay:.02s}
  .reveal-stagger.in > *:nth-child(2){transition-delay:.10s}
  .reveal-stagger.in > *:nth-child(3){transition-delay:.18s}
  .reveal-stagger.in > *:nth-child(4){transition-delay:.26s}
  .reveal-stagger.in > *:nth-child(5){transition-delay:.34s}
  .reveal-stagger.in > *:nth-child(6){transition-delay:.42s}
  @media (prefers-reduced-motion: reduce){
    .reveal, .reveal-stagger > *{opacity:1!important; transform:none!important; transition:none!important}
  }

  /* ================= NAV ================= */
  #nav{
    position:fixed; inset:0 0 auto 0; z-index:100; padding:14px 0;
    transition:background .35s ease, box-shadow .35s ease, padding .35s ease, border-color .35s ease;
    border-bottom:1px solid transparent;
  }
  #nav.scrolled{background:color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter:blur(14px); box-shadow:var(--shadow); border-color:var(--border); padding:8px 0}
  .nav-row{display:flex; align-items:center; justify-content:space-between; gap:20px}
  .brand{display:flex; align-items:center; gap:10px; font-family:'Fraunces',serif; font-weight:700; font-size:20px; flex-shrink:0}
  .brand-mark{width:36px;height:36px;border-radius:10px; object-fit:contain; flex-shrink:0}
  .brand b{color:var(--red)}
  .brand-logo img{height:34px; width:auto; display:block}
  @media (max-width:560px){.brand-logo img{height:28px}}
  .nav-links{display:flex; align-items:center; gap:2px; list-style:none; margin:0; padding:0}
  /* Default (unscrolled) nav sits over the hero's dark video overlay, so
     links/toggles/burger need light colors here; #nav.scrolled below
     switches them back to the normal dark-on-white palette once the
     backdrop becomes an opaque light bar. */
  .nav-links a{
    position:relative; padding:9px 16px; font-size:14.5px; font-weight:600; color:rgba(255,255,255,.85);
    border-radius:999px; transition:color .2s ease;
  }
  .nav-links a::after{
    content:""; position:absolute; left:16px; right:16px; bottom:4px; height:2px; background:var(--red);
    transform:scaleX(0); transform-origin:left; transition:transform .25s cubic-bezier(.16,1,.3,1);
  }
  .nav-links a:hover{color:#fff}
  .nav-links a.active{color:#fff; font-weight:700}
  .nav-links a.active::after{transform:scaleX(1)}
  #nav.scrolled .nav-links a{color:var(--ink-soft)}
  #nav.scrolled .nav-links a:hover,
  #nav.scrolled .nav-links a.active{color:var(--ink)}
  .nav-actions{display:flex; align-items:center; gap:10px; flex-shrink:0}
  .lang-toggle{
    display:flex; border:1px solid rgba(255,255,255,.3); border-radius:999px; padding:3px; gap:2px; background:rgba(255,255,255,.08);
  }
  .lang-toggle button{
    border:none; background:none; font:inherit; font-size:12.5px; font-weight:700; padding:5px 10px; border-radius:999px;
    color:rgba(255,255,255,.75); cursor:pointer; transition:background .2s ease, color .2s ease;
  }
  .lang-toggle button.active{background:#fff; color:var(--ink)}
  #nav.scrolled .lang-toggle{border-color:var(--border); background:var(--surface)}
  #nav.scrolled .lang-toggle button{color:var(--ink-soft)}
  #nav.scrolled .lang-toggle button.active{background:var(--ink); color:var(--bg)}
  .btn{
    display:inline-flex; align-items:center; justify-content:center; gap:8px; font:inherit; font-weight:700; font-size:14.5px;
    padding:11px 22px; border-radius:999px; border:1px solid transparent; cursor:pointer; white-space:nowrap;
    transition:transform .2s cubic-bezier(.16,1,.3,1), box-shadow .2s ease, background .2s ease, border-color .2s ease;
  }
  .btn:active{transform:scale(.97)}
  .btn-primary{background:var(--red); color:#fff; box-shadow:0 10px 24px -10px rgba(239,61,61,.55)}
  .btn-primary:hover{background:var(--red-deep); box-shadow:0 14px 28px -10px rgba(239,61,61,.65); transform:translateY(-1px)}
  .btn-ghost{background:transparent; border-color:var(--border); color:var(--ink)}
  .btn-ghost:hover{background:var(--surface); border-color:var(--ink-soft)}
  .btn-light{background:#fff; color:var(--ink)}
  .btn-light:hover{transform:translateY(-1px); box-shadow:var(--shadow-lg)}
  .nav-burger{display:none; width:40px;height:40px;border-radius:10px;border:1px solid rgba(255,255,255,.3);background:rgba(255,255,255,.08);align-items:center;justify-content:center;cursor:pointer}
  .nav-burger span, .nav-burger span::before, .nav-burger span::after{content:"";display:block;width:18px;height:2px;background:#fff;border-radius:2px;position:relative;transition:.25s}
  #nav.scrolled .nav-burger{border-color:var(--border); background:var(--surface)}
  #nav.scrolled .nav-burger span,
  #nav.scrolled .nav-burger span::before,
  #nav.scrolled .nav-burger span::after{background:var(--ink)}
  .nav-burger span::before{position:absolute;top:-6px}
  .nav-burger span::after{position:absolute;top:6px}

  #mobile-menu{
    position:fixed; inset:0; z-index:99; background:var(--bg); padding:96px 24px 40px;
    display:none; flex-direction:column; gap:4px;
  }
  #mobile-menu.open{display:flex}
  #mobile-menu a{padding:14px 6px; font-size:17px; font-weight:600; border-bottom:1px solid var(--border)}
  #mobile-menu a.active{color:var(--red)}
  #mobile-menu .btn{margin-top:18px}

  /* ================= HERO ================= */
  #hero{min-height:100svh; display:flex; align-items:center; padding-top:96px; overflow:hidden}
  .hero-media{position:absolute; inset:0; z-index:0}
  .hero-media video, .hero-media img{width:100%;height:100%;object-fit:cover; position:absolute; inset:0}
  .hero-media::after{
    content:""; position:absolute; inset:0;
    background:linear-gradient(180deg, rgba(10,14,20,.55) 0%, rgba(10,14,20,.72) 60%, rgba(10,14,20,.86) 100%);
  }
  #network-canvas{position:absolute; inset:0; z-index:1; opacity:.55}
  .hero-content{position:relative; z-index:2; color:#fff; padding-block:64px}
  .hero-eyebrow{color:#8fd3ff}
  .hero-eyebrow::before{background:var(--red)}
  .hero-content h1{font-size:clamp(34px,6vw,64px); font-weight:700; color:#fff; margin-top:18px; max-width:820px}
  .hero-content h1 em{font-style:normal; color:var(--amber)}
  .hero-sub{font-size:clamp(15px,1.6vw,18px); color:rgba(255,255,255,.82); max-width:600px; margin-top:18px}
  .hero-ctas{display:flex; gap:12px; margin-top:32px; flex-wrap:wrap}
  .hero-stats{display:flex; gap:36px; margin-top:56px; flex-wrap:wrap}
  .hero-stat b{display:block; font-family:'Fraunces',serif; font-size:clamp(24px,3vw,34px); color:#fff}
  .hero-stat span{font-size:13px; color:rgba(255,255,255,.68)}
  .scroll-cue{
    position:absolute; left:50%; bottom:28px; transform:translateX(-50%); z-index:2; color:rgba(255,255,255,.75);
    display:flex; flex-direction:column; align-items:center; gap:8px; font-size:11px; letter-spacing:.1em; text-transform:uppercase;
    animation:bob 2.2s ease-in-out infinite;
  }
  .scroll-cue svg{width:16px}
  @keyframes bob{0%,100%{transform:translate(-50%,0)}50%{transform:translate(-50%,8px)}}

  /* ================= MARQUEE ================= */
  .marquee-wrap{border-block:1px solid var(--border); background:var(--surface); overflow:hidden; padding:18px 0}
  .marquee-track{display:flex; gap:56px; width:max-content; animation:scroll-left 26s linear infinite}
  .marquee-track span{font-size:14px; font-weight:600; color:var(--ink-soft); white-space:nowrap; display:flex; align-items:center; gap:10px}
  .marquee-track span::before{content:"●"; color:var(--red); font-size:8px}
  @keyframes scroll-left{from{transform:translateX(0)}to{transform:translateX(-50%)}}

  /* ================= SECTION HEAD ================= */
  .section-head{max-width:640px; margin-bottom:48px}
  .section-head h2{font-size:clamp(26px,4vw,42px); margin-top:14px}
  .section-head p{color:var(--ink-soft); font-size:16px; margin-top:14px}
  .section-pad{padding-block:104px}
  @media (max-width:720px){.section-pad{padding-block:72px}}

  /* ================= MISSION / ABOUT ================= */
  #about .about-grid{display:grid; grid-template-columns:1.05fr .95fr; gap:64px; align-items:center}
  .about-visual{position:relative; border-radius:24px; overflow:hidden; box-shadow:var(--shadow-lg); aspect-ratio:4/5}
  .about-visual img{width:100%;height:100%;object-fit:cover}
  .about-badge{
    position:absolute; left:20px; bottom:20px; background:var(--surface); border-radius:16px; padding:16px 18px;
    box-shadow:var(--shadow-lg); display:flex; align-items:center; gap:12px; max-width:230px;
  }
  .about-badge .ring{width:44px;height:44px;border-radius:50%;background:conic-gradient(var(--blue) 0 78%, var(--border) 0);display:flex;align-items:center;justify-content:center;flex-shrink:0}
  .about-badge .ring i{width:36px;height:36px;border-radius:50%;background:var(--surface);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:12px;font-style:normal}
  .about-badge strong{display:block; font-size:13.5px}
  .about-badge span{font-size:12px; color:var(--ink-soft)}
  .about-list{list-style:none; margin:28px 0 0; padding:0; display:grid; gap:16px}
  .about-list li{display:flex; gap:14px; align-items:flex-start}
  .about-list .ic{width:30px;height:30px;border-radius:9px;background:rgba(30,155,233,.12);color:var(--blue-deep);display:flex;align-items:center;justify-content:center;flex-shrink:0;font-size:15px}
  .about-list strong{font-size:15px}
  .about-list p{margin:2px 0 0; font-size:14px; color:var(--ink-soft)}

  /* ================= FEATURES ================= */
  .feature-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:22px}
  .feature-card{
    background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:28px;
    transition:transform .35s cubic-bezier(.16,1,.3,1), box-shadow .35s ease, border-color .35s ease;
  }
  .feature-card:hover{transform:translateY(-6px); box-shadow:var(--shadow-lg); border-color:transparent}
  .feature-ic{width:48px;height:48px;border-radius:14px;display:flex;align-items:center;justify-content:center;font-size:22px;margin-bottom:18px}
  .feature-card:nth-child(6n+1) .feature-ic{background:rgba(30,155,233,.14); color:var(--blue-deep)}
  .feature-card:nth-child(6n+2) .feature-ic{background:rgba(239,61,61,.13); color:var(--red-deep)}
  .feature-card:nth-child(6n+3) .feature-ic{background:rgba(245,166,35,.16); color:#a86a0e}
  .feature-card:nth-child(6n+4) .feature-ic{background:rgba(30,155,233,.14); color:var(--blue-deep)}
  .feature-card:nth-child(6n+5) .feature-ic{background:rgba(239,61,61,.13); color:var(--red-deep)}
  .feature-card:nth-child(6n+6) .feature-ic{background:rgba(245,166,35,.16); color:#a86a0e}
  .feature-card h3{font-size:17.5px}
  .feature-card p{font-size:14px; color:var(--ink-soft); margin-top:10px}

  /* ================= HOW IT WORKS ================= */
  #how{background:var(--surface); border-block:1px solid var(--border)}
  .steps{display:grid; grid-template-columns:repeat(4,1fr); gap:0; counter-reset:step; position:relative}
  .steps::before{content:""; position:absolute; top:26px; left:12.5%; right:12.5%; height:1px; background:var(--border)}
  .step{position:relative; text-align:center; padding-inline:14px}
  .step-num{
    width:52px;height:52px;border-radius:50%; background:var(--bg); border:1px solid var(--border); margin:0 auto 20px;
    display:flex; align-items:center; justify-content:center; font-family:'Fraunces',serif; font-weight:700; font-size:18px;
    position:relative; z-index:1; color:var(--red-deep);
  }
  .step h4{font-size:16px}
  .step p{font-size:13.5px; color:var(--ink-soft); margin-top:8px}
  @media (max-width:860px){
    .steps{grid-template-columns:1fr 1fr; gap:36px 20px}
    .steps::before{display:none}
  }

  /* ================= APPS ================= */
  #apps{background:linear-gradient(160deg,#0f6fb8 0%, #123047 70%, #1a1712 100%); color:#fff}
  #apps .container{display:grid; grid-template-columns:1fr 1fr; gap:56px; align-items:center}
  #apps .section-head p{color:rgba(255,255,255,.72)}
  #apps .eyebrow{color:#8fd3ff}
  #apps h2{color:#fff}
  .store-row{display:flex; gap:12px; margin-top:28px; flex-wrap:wrap}
  .store-btn{
    display:flex; align-items:center; gap:10px; background:rgba(255,255,255,.08); border:1px solid rgba(255,255,255,.18);
    border-radius:14px; padding:10px 18px; transition:background .2s ease, transform .2s ease;
  }
  .store-btn:hover{background:rgba(255,255,255,.16); transform:translateY(-2px)}
  .store-btn.disabled{opacity:.5; cursor:not-allowed}
  .store-btn .store-ic{font-size:22px}
  .store-btn small{display:block; font-size:10px; opacity:.75; text-transform:uppercase; letter-spacing:.05em}
  .store-btn strong{display:block; font-size:15px}
  .phone-mock{position:relative; display:flex; justify-content:center}
  .phone-frame{
    width:min(280px,70vw); aspect-ratio:9/19; border-radius:38px; background:#0b0f14; padding:12px;
    box-shadow:var(--shadow-lg); position:relative; border:1px solid rgba(255,255,255,.12);
  }
  .phone-frame .screen{width:100%;height:100%;border-radius:26px;overflow:hidden; position:relative}
  .phone-frame .screen img{width:100%;height:100%;object-fit:cover}
  .float-chip{position:absolute; background:#fff; color:var(--ink); border-radius:14px; padding:10px 14px; box-shadow:var(--shadow-lg); font-size:12.5px; font-weight:700; display:flex; align-items:center; gap:8px}
  .float-chip.c1{top:8%; left:-8%; animation:float1 5s ease-in-out infinite}
  .float-chip.c2{bottom:14%; right:-10%; animation:float2 6s ease-in-out infinite}
  @keyframes float1{0%,100%{transform:translateY(0)}50%{transform:translateY(-10px)}}
  @keyframes float2{0%,100%{transform:translateY(0)}50%{transform:translateY(10px)}}

  /* ================= TESTIMONIALS ================= */
  .test-track-wrap{overflow:hidden; margin-top:12px; -webkit-mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent); mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent)}
  .test-track{display:flex; gap:20px; width:max-content; animation:scroll-left 46s linear infinite}
  .test-track:hover{animation-play-state:paused}
  .test-card{
    width:340px; flex-shrink:0; background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:26px;
  }
  .stars{color:var(--amber); font-size:14px; letter-spacing:2px}
  .test-card p{font-size:14.5px; color:var(--ink-soft); margin-top:14px; line-height:1.6}
  .test-person{display:flex; align-items:center; gap:12px; margin-top:20px}
  .test-avatar{width:40px;height:40px;border-radius:50%; display:flex;align-items:center;justify-content:center; font-weight:700; color:#fff; font-size:14px; flex-shrink:0}
  .test-person strong{display:block; font-size:13.5px}
  .test-person span{font-size:12px; color:var(--ink-soft)}

  /* ================= FAQ ================= */
  #faq{background:var(--surface); border-block:1px solid var(--border)}
  .faq-list{max-width:820px; margin:0 auto; display:grid; gap:12px}
  .faq-item{border:1px solid var(--border); border-radius:16px; background:var(--bg); overflow:hidden}
  .faq-q{
    width:100%; text-align:left; background:none; border:none; font:inherit; color:var(--ink); cursor:pointer;
    display:flex; align-items:center; justify-content:space-between; gap:16px; padding:20px 24px; font-size:15.5px; font-weight:600;
  }
  .faq-q .plus{width:22px;height:22px;flex-shrink:0; position:relative}
  .faq-q .plus::before, .faq-q .plus::after{content:"";position:absolute; background:var(--ink-soft); border-radius:2px; transition:transform .3s ease, opacity .3s ease}
  .faq-q .plus::before{left:0;top:50%;width:100%;height:2px;transform:translateY(-50%)}
  .faq-q .plus::after{top:0;left:50%;width:2px;height:100%;transform:translateX(-50%)}
  .faq-item.open .faq-q .plus::after{opacity:0; transform:translateX(-50%) rotate(90deg)}
  .faq-item.open .faq-q{color:var(--red-deep)}
  .faq-a{max-height:0; overflow:hidden; transition:max-height .35s cubic-bezier(.16,1,.3,1)}
  .faq-a p{padding:0 24px 22px; font-size:14.5px; color:var(--ink-soft); margin:0}

  /* ================= CONTACT ================= */
  #contact .contact-grid{display:grid; grid-template-columns:.9fr 1.1fr; gap:56px}
  .contact-info{display:grid; gap:20px; align-content:start}
  .contact-item{display:flex; gap:14px; align-items:flex-start}
  .contact-item .ic{width:42px;height:42px;border-radius:12px; background:rgba(30,155,233,.12); color:var(--blue-deep); display:flex; align-items:center; justify-content:center; flex-shrink:0}
  .contact-item strong{font-size:14.5px; display:block}
  .contact-item span, .contact-item a{font-size:14px; color:var(--ink-soft)}
  .contact-item a:hover{color:var(--blue-deep)}
  .contact-form{background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:32px; box-shadow:var(--shadow)}
  .form-row{display:grid; grid-template-columns:1fr 1fr; gap:16px}
  .field{display:grid; gap:7px; margin-bottom:16px}
  .field label{font-size:13px; font-weight:600; color:var(--ink-soft)}
  .field input, .field select, .field textarea{
    font:inherit; font-size:14.5px; padding:11px 14px; border-radius:10px; border:1px solid var(--border); background:var(--bg); color:var(--ink);
    outline:none; transition:border-color .2s ease, box-shadow .2s ease;
  }
  .field input:focus, .field select:focus, .field textarea:focus{border-color:var(--blue); box-shadow:0 0 0 3px rgba(30,155,233,.15)}
  .field textarea{resize:vertical; min-height:96px; font-family:inherit}
  .form-note{font-size:12.5px; color:var(--ink-soft); margin-top:14px; text-align:center}
  .form-success{display:none; text-align:center; padding:36px 0}
  .form-success.show{display:block}
  .form-success .tick{width:56px;height:56px;border-radius:50%;background:rgba(34,197,94,.14);color:#16a34a;display:flex;align-items:center;justify-content:center;margin:0 auto 16px;font-size:26px}

  /* ================= CTA BAND ================= */
  #cta-band{
    background:linear-gradient(120deg, var(--red) 0%, var(--red-deep) 100%); color:#fff; text-align:center; border-radius:28px;
    padding:56px 32px; margin:0 24px; max-width:1132px; margin-inline:auto;
  }
  #cta-band h2{color:#fff; font-size:clamp(24px,4vw,38px)}
  #cta-band p{color:rgba(255,255,255,.85); margin-top:12px; font-size:15.5px}
  #cta-band .hero-ctas{justify-content:center; margin-top:26px}

  /* ================= FOOTER ================= */
  footer{background:#121210; color:#c9c7c1; padding-top:72px}
  footer a{color:#c9c7c1}
  footer a:hover{color:#fff}
  .footer-top{display:grid; grid-template-columns:1.4fr 1fr 1fr 1fr; gap:40px; padding-bottom:52px; border-bottom:1px solid rgba(255,255,255,.08)}
  .footer-brand .brand{color:#fff}
  .footer-brand p{font-size:13.5px; color:#8f8d87; margin-top:14px; max-width:280px}
  .footer-social{display:flex; gap:10px; margin-top:20px}
  .footer-social a{width:36px;height:36px;border-radius:10px;background:rgba(255,255,255,.06);display:flex;align-items:center;justify-content:center; font-size:14px; transition:background .2s ease}
  .footer-social a:hover{background:rgba(255,255,255,.14)}
  .footer-col h5{font-size:12.5px; text-transform:uppercase; letter-spacing:.08em; color:#8f8d87; margin-bottom:18px; font-family:inherit; font-weight:700}
  .footer-col ul{list-style:none; margin:0; padding:0; display:grid; gap:11px}
  .footer-col a{font-size:14px}
  .footer-bottom{display:flex; justify-content:space-between; align-items:center; padding:26px 0; flex-wrap:wrap; gap:12px; font-size:12.5px; color:#8f8d87}
  .footer-bottom a{color:#c9c7c1; font-weight:600}

  /* ================= SCROLL TOP ================= */
  #scrolltop{
    position:fixed; right:22px; bottom:22px; width:52px;height:52px; border-radius:50%; z-index:90;
    background:var(--surface); border:none; cursor:pointer; box-shadow:var(--shadow-lg);
    display:flex; align-items:center; justify-content:center; opacity:0; transform:translateY(16px) scale(.9); pointer-events:none;
    transition:opacity .3s ease, transform .3s ease;
  }
  #scrolltop.show{opacity:1; transform:none; pointer-events:auto}
  #scrolltop svg{position:absolute; inset:0; transform:rotate(-90deg)}
  #scrolltop svg circle{fill:none; stroke-width:3}
  #scrolltop svg circle.track{stroke:var(--border)}
  #scrolltop svg circle.bar{stroke:var(--red); stroke-linecap:round; transition:stroke-dashoffset .1s linear}
  #scrolltop .arrow{position:relative; z-index:1; color:var(--ink); font-size:16px}

  /* ================= FLOATING ZALO ================= */
  #zalo-float{
    position:fixed; right:22px; bottom:88px; z-index:91; width:56px; height:56px; border-radius:50%;
    background:#0068ff; display:flex; align-items:center; justify-content:center; box-shadow:0 10px 26px -8px rgba(0,104,255,.6);
    transition:transform .25s cubic-bezier(.16,1,.3,1), box-shadow .25s ease, bottom .3s ease;
  }
  #zalo-float:hover{transform:translateY(-3px) scale(1.05); box-shadow:0 14px 30px -8px rgba(0,104,255,.7)}
  #zalo-float.lift{bottom:150px}
  #zalo-float .ring{position:absolute; inset:0; border-radius:50%; border:2px solid #0068ff; animation:zalo-pulse 2.4s ease-out infinite}
  #zalo-float img, #zalo-float svg{position:relative; z-index:1; width:30px; height:30px}
  #zalo-float .tip{
    position:absolute; right:66px; top:50%; transform:translateY(-50%) translateX(6px); background:var(--ink); color:var(--bg);
    font-size:12.5px; font-weight:600; padding:7px 12px; border-radius:8px; white-space:nowrap; opacity:0; pointer-events:none;
    transition:opacity .2s ease, transform .2s ease;
  }
  #zalo-float:hover .tip{opacity:1; transform:translateY(-50%) translateX(0)}
  @keyframes zalo-pulse{0%{transform:scale(1); opacity:.7}100%{transform:scale(1.7); opacity:0}}
  @media (prefers-reduced-motion: reduce){#zalo-float .ring{animation:none}}
  @media (max-width:560px){
    #zalo-float{right:16px; bottom:80px; width:50px; height:50px}
    #zalo-float.lift{bottom:140px}
    #zalo-float img, #zalo-float svg{width:26px;height:26px}
  }

  /* ================= MODAL (legal pages) ================= */
  .modal-overlay{position:fixed; inset:0; background:rgba(10,10,8,.55); z-index:200; display:none; align-items:flex-start; justify-content:center; padding:5vh 20px; overflow-y:auto}
  .modal-overlay.open{display:flex}
  .modal-box{background:var(--surface); border-radius:20px; max-width:720px; width:100%; padding:40px; box-shadow:var(--shadow-lg); position:relative; margin-bottom:5vh}
  .modal-box h3{font-size:24px}
  .modal-box .close-modal{position:absolute; top:20px; right:20px; width:34px;height:34px; border-radius:50%; border:1px solid var(--border); background:var(--bg); cursor:pointer; font-size:15px}
  .modal-box .modal-body{margin-top:20px; font-size:14.5px; color:var(--ink-soft); display:grid; gap:14px; max-height:60vh; overflow-y:auto; padding-right:6px}
  .modal-box .modal-body h4{font-size:15px; color:var(--ink); margin-top:6px}

  @media (max-width:960px){
    .nav-links, .nav-actions .btn-ghost{display:none}
    .nav-burger{display:flex}
    #about .about-grid, #apps .container, #contact .contact-grid{grid-template-columns:1fr}
    .feature-grid{grid-template-columns:1fr 1fr}
    .hero-stats{gap:26px}
    .form-row{grid-template-columns:1fr}
    .footer-top{grid-template-columns:1fr 1fr; row-gap:32px}
  }
  @media (max-width:560px){
    .feature-grid{grid-template-columns:1fr}
    .footer-top{grid-template-columns:1fr}
    #cta-band{margin-inline:12px; padding:40px 22px}
  }