:root{
  --bg:#0b0d12; --bg2:#10131a; --panel:#151922; --panel2:#1c212c; --line:#262c38; --line2:#323a49;
  --txt:#eef1f6; --mut:#9aa3b5; --dim:#6b7486;
  --acc:#ff3b30; --acc2:#ff6a3d; --ok:#22c55e; --blue:#3b82f6; --warn:#f59e0b;
  --r:16px; --wrap:1160px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:'Be Vietnam Pro',system-ui,'Segoe UI',Arial,sans-serif;background:var(--bg);color:var(--txt);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 20px}
.sec{padding:96px 0;position:relative;scroll-margin-top:60px}
.sec.alt{background:var(--bg2);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.eyebrow{display:inline-flex;align-items:center;gap:8px;font-size:13px;font-weight:600;letter-spacing:.6px;text-transform:uppercase;color:var(--acc2)}
.eyebrow::before{content:"";width:7px;height:7px;border-radius:50%;background:var(--acc);box-shadow:0 0 0 4px rgba(255,59,48,.18)}
h1,h2,h3{line-height:1.2;letter-spacing:-.4px}
h2.title{font-size:clamp(28px,4vw,42px);font-weight:800;margin:12px 0 14px}
p.lead{font-size:18px;color:var(--mut);max-width:720px}
.center{text-align:center}.center p.lead{margin:0 auto}
.grad{background:linear-gradient(90deg,var(--acc),var(--acc2));-webkit-background-clip:text;background-clip:text;color:transparent}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;font:inherit;font-weight:700;font-size:15px;border:0;border-radius:12px;padding:14px 22px;cursor:pointer;transition:transform .15s,box-shadow .15s,background .15s;white-space:nowrap}
.btn:hover{transform:translateY(-1px)}
.btn-p{background:linear-gradient(135deg,var(--acc),var(--acc2));color:#fff;box-shadow:0 10px 30px -10px rgba(255,59,48,.7)}
.btn-p:hover{box-shadow:0 14px 34px -10px rgba(255,59,48,.85)}
.btn-g{background:var(--panel2);color:var(--txt);border:1px solid var(--line2)}
.btn-g:hover{background:#232938}
.btn-ok{background:var(--ok);color:#04210f}
.btn-sm{padding:9px 14px;font-size:13px;border-radius:10px}
.btn-block{width:100%}
.btn[disabled]{opacity:.6;cursor:wait;transform:none}

/* nav */
.nav{position:sticky;top:0;z-index:50;background:rgba(11,13,18,.82);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.nav .wrap{display:flex;align-items:center;gap:28px;height:68px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:20px}
.logo i{width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,var(--acc),var(--acc2));display:grid;place-items:center;font-style:normal;font-size:15px;color:#fff;box-shadow:0 6px 18px -6px rgba(255,59,48,.8)}
.logo small{display:block;font-size:10px;font-weight:500;color:var(--mut);letter-spacing:.3px;margin-top:-3px}
.nav .links{display:flex;gap:22px;margin-left:auto;font-size:14px;color:var(--mut)}
.nav .links a:hover{color:var(--txt)}
.nav .menu-btn{display:none;margin-left:auto;background:none;border:1px solid var(--line2);color:var(--txt);border-radius:10px;width:42px;height:42px;font-size:18px;cursor:pointer}
@media (max-width:900px){
  .nav .links{display:none;position:absolute;top:68px;left:0;right:0;flex-direction:column;gap:0;background:var(--bg2);border-bottom:1px solid var(--line);padding:6px 20px 14px}
  .nav .links a{padding:12px 0;border-bottom:1px solid var(--line)}
  .nav.open .links{display:flex}
  .nav .menu-btn{display:block}
  .nav .cta-top{display:none}
}

/* hero */
.hero{padding:70px 0 90px;overflow:hidden}
.hero::before{content:"";position:absolute;inset:-200px -100px auto auto;width:700px;height:700px;background:radial-gradient(closest-side,rgba(255,59,48,.22),transparent);pointer-events:none}
.hero::after{content:"";position:absolute;inset:auto auto -260px -200px;width:640px;height:640px;background:radial-gradient(closest-side,rgba(59,130,246,.14),transparent);pointer-events:none}
.hero .wrap{display:grid;grid-template-columns:1.02fr 1fr;gap:56px;align-items:center;position:relative;z-index:1}
.hero .wrap>*{min-width:0}
.hero h1{font-size:clamp(34px,5.2vw,58px);font-weight:800;margin:18px 0 18px}
.hero p.lead{font-size:19px}
.hero .ctas{display:flex;gap:12px;flex-wrap:wrap;margin:30px 0 22px}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{font-size:13px;color:var(--mut);background:var(--panel);border:1px solid var(--line);border-radius:999px;padding:6px 12px}
.chip b{color:var(--txt)}
.refbar{display:none;margin-top:18px;font-size:14px;color:#bfe9cf;background:rgba(34,197,94,.08);border:1px solid rgba(34,197,94,.3);border-radius:12px;padding:10px 14px}
@media (max-width:960px){.hero .wrap{grid-template-columns:1fr}.hero{padding-top:40px}}

/* app mock */
.mock{background:#0e1117;border:1px solid var(--line2);border-radius:18px;overflow:hidden;box-shadow:0 40px 80px -30px rgba(0,0,0,.8),0 0 0 1px rgba(255,255,255,.02);transform:perspective(1400px) rotateY(-6deg) rotateX(2deg)}
@media (max-width:960px){.mock{transform:none}}
.winbar{height:30px;background:#090b0f;display:flex;align-items:center;gap:7px;padding:0 12px;border-bottom:1px solid var(--line)}
.winbar i{width:10px;height:10px;border-radius:50%;display:block}
.winbar i:nth-child(1){background:#ff5f57}.winbar i:nth-child(2){background:#febc2e}.winbar i:nth-child(3){background:#28c840}
.winbar span{margin-left:8px;font-size:11px;color:var(--dim)}
.app{display:grid;grid-template-columns:140px 1fr;min-height:360px}
.side{background:var(--panel);border-right:1px solid var(--line);padding:12px 0;font-size:12px}
.side .b{padding:0 14px 10px;border-bottom:1px solid var(--line);margin-bottom:6px}
.side .b b{color:var(--acc);font-size:17px;font-weight:800}
.side .b s{display:block;text-decoration:none;color:var(--dim);font-size:9px;text-transform:uppercase;letter-spacing:.4px}
.side .n{padding:7px 14px;color:var(--mut)}
.side .n.on{background:var(--acc);color:#fff;border-radius:8px;margin:0 8px;padding:7px 8px}
.side .h{padding:10px 14px 2px;color:var(--dim);font-size:9px;text-transform:uppercase;letter-spacing:.6px}
.side .ver{margin:14px 14px 0;font-size:10px;color:var(--dim)}
.mn{padding:0 0 10px}
.mn .top{display:flex;gap:8px;align-items:center;padding:10px 12px;border-bottom:1px solid var(--line)}
.pill{font-size:11px;background:var(--panel2);border:1px solid var(--line);border-radius:8px;padding:6px 9px;color:var(--mut)}
.pill.r{background:var(--acc);border-color:var(--acc);color:#fff;font-weight:700}
.gsep{margin:10px 12px 0;color:var(--dim);font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.5px}
.row{display:grid;grid-template-columns:1.7fr 1fr auto;gap:8px;align-items:center;background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:9px 11px;margin:7px 12px}
.row .nm{font-weight:700;font-size:12.5px;display:flex;gap:7px;align-items:center}
.row .s{color:var(--dim);font-size:10.5px}
.dot{width:8px;height:8px;border-radius:50%;background:var(--ok);flex:none;box-shadow:0 0 0 3px rgba(34,197,94,.15)}
.dot.off{background:#4b5466;box-shadow:none}
.go{font-size:10.5px;font-weight:700;background:var(--ok);color:#04210f;border-radius:7px;padding:5px 9px}
@media (max-width:520px){.app{grid-template-columns:1fr}.side{display:none}.row{grid-template-columns:1fr auto}.row .s.ip{display:none}}

/* grid cards */
.grid{display:grid;gap:18px}
.g2{grid-template-columns:repeat(2,1fr)}.g3{grid-template-columns:repeat(3,1fr)}.g4{grid-template-columns:repeat(4,1fr)}
@media (max-width:980px){.g3,.g4{grid-template-columns:repeat(2,1fr)}}
@media (max-width:640px){.g2,.g3,.g4{grid-template-columns:1fr}}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:26px;transition:border-color .2s,transform .2s}
.card:hover{border-color:var(--line2);transform:translateY(-2px)}
.card .ic{width:46px;height:46px;border-radius:12px;display:grid;place-items:center;font-size:22px;background:rgba(255,59,48,.1);border:1px solid rgba(255,59,48,.25);margin-bottom:16px}
.card .ic.b{background:rgba(59,130,246,.1);border-color:rgba(59,130,246,.3)}
.card .ic.g{background:rgba(34,197,94,.1);border-color:rgba(34,197,94,.3)}
.card .ic.w{background:rgba(245,158,11,.1);border-color:rgba(245,158,11,.3)}
.card h3{font-size:18px;margin-bottom:8px}
.card p{color:var(--mut);font-size:15px}
.mt{margin-top:46px}

/* steps */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;counter-reset:s}
@media (max-width:860px){.steps{grid-template-columns:1fr}}
.step{position:relative;background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:28px 26px 26px}
.step::before{counter-increment:s;content:counter(s);position:absolute;top:-18px;left:24px;width:38px;height:38px;border-radius:12px;background:linear-gradient(135deg,var(--acc),var(--acc2));display:grid;place-items:center;font-weight:800;color:#fff;box-shadow:0 8px 20px -8px rgba(255,59,48,.9)}
.step h3{font-size:18px;margin:8px 0 6px}.step p{color:var(--mut);font-size:15px}
.formula{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:12px;margin-top:34px;font-weight:700}
.formula span{background:var(--panel);border:1px solid var(--line2);border-radius:12px;padding:12px 18px}
.formula em{font-style:normal;color:var(--acc2);font-size:22px}
.formula span.res{background:rgba(34,197,94,.08);border-color:rgba(34,197,94,.35);color:#c9f2d8}

/* compare */
.tbl{width:100%;border-collapse:separate;border-spacing:0;background:var(--panel);border:1px solid var(--line);border-radius:var(--r);overflow:hidden;font-size:15px}
.tbl th,.tbl td{padding:16px 18px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
.tbl tr:last-child td{border-bottom:0}
.tbl th{font-size:13px;text-transform:uppercase;letter-spacing:.5px;color:var(--mut);background:var(--panel2)}
.tbl th.us{color:#fff;background:linear-gradient(135deg,rgba(255,59,48,.35),rgba(255,106,61,.25))}
.tbl td:first-child{color:var(--mut);font-weight:600;width:26%}
.tbl td.us{color:#fff;background:rgba(255,59,48,.05)}
.tbl .x{color:#f87171}.tbl .v{color:#4ade80}
.tblwrap{overflow-x:auto;border-radius:var(--r)}
.tblwrap .tbl{min-width:640px}

/* pricing */
.plans{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:46px;align-items:stretch}
@media (max-width:1040px){.plans{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.plans{grid-template-columns:1fr}}
.plan{position:relative;background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:28px 24px;display:flex;flex-direction:column}
.plan.best{border-color:rgba(255,59,48,.7);background:linear-gradient(180deg,rgba(255,59,48,.12),var(--panel) 45%);box-shadow:0 30px 60px -30px rgba(255,59,48,.55)}
.plan .badge{position:absolute;top:-13px;left:50%;transform:translateX(-50%);background:linear-gradient(135deg,var(--acc),var(--acc2));color:#fff;font-size:12px;font-weight:800;letter-spacing:.5px;padding:5px 12px;border-radius:999px;white-space:nowrap}
.plan h3{font-size:18px}
.plan .tag{color:var(--mut);font-size:13px;margin-top:2px}
.plan .price{font-size:36px;font-weight:800;margin:18px 0 0;letter-spacing:-1px}
.plan .price small{font-size:15px;font-weight:600;color:var(--mut);letter-spacing:0}
.plan .per{color:var(--mut);font-size:13px;min-height:20px}
.plan .save{display:inline-block;margin-top:8px;font-size:12px;font-weight:700;color:#4ade80;background:rgba(34,197,94,.1);border:1px solid rgba(34,197,94,.3);border-radius:999px;padding:2px 9px}
.plan ul{list-style:none;margin:20px 0 24px;display:grid;gap:9px;font-size:14px;color:#cdd3de;flex:1}
.plan li::before{content:"✓";color:var(--ok);font-weight:800;margin-right:8px}
.note{margin-top:26px;background:var(--panel);border:1px solid var(--line);border-left:4px solid var(--blue);border-radius:12px;padding:16px 18px;color:var(--mut);font-size:15px}
.note b{color:var(--txt)}
.note.w{border-left-color:var(--warn)}
.note.g{border-left-color:var(--ok)}

/* honest block */
.two{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-top:40px}
@media (max-width:800px){.two{grid-template-columns:1fr}}
.box{border-radius:var(--r);padding:26px;border:1px solid}
.box.g{background:rgba(34,197,94,.06);border-color:rgba(34,197,94,.3)}
.box.b{background:rgba(59,130,246,.06);border-color:rgba(59,130,246,.3)}
.box h3{font-size:18px;margin-bottom:12px}
.box ul{list-style:none;display:grid;gap:10px;color:#cdd3de;font-size:15px}
.box.g li::before{content:"✓  ";color:var(--ok);font-weight:800}
.box.b li::before{content:"•  ";color:var(--blue);font-weight:800}

/* faq */
.faq{max-width:860px;margin:40px auto 0;display:grid;gap:12px}
.faq details{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:0 22px}
.faq details[open]{border-color:var(--line2)}
.faq summary{list-style:none;cursor:pointer;padding:18px 0;font-weight:700;font-size:16px;display:flex;justify-content:space-between;gap:16px}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";color:var(--acc2);font-size:22px;line-height:1;transition:transform .2s}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq details p{color:var(--mut);padding:0 0 18px;font-size:15px}

/* band */
.band{border-radius:24px;padding:46px;display:grid;grid-template-columns:1.3fr 1fr;gap:30px;align-items:center;background:radial-gradient(600px 300px at 0% 0%,rgba(255,59,48,.25),transparent),radial-gradient(500px 300px at 100% 100%,rgba(59,130,246,.18),transparent),var(--panel);border:1px solid var(--line2)}
.band h2{font-size:clamp(26px,3.4vw,36px);font-weight:800;margin:10px 0}
.band p{color:var(--mut)}
.band .big{font-size:clamp(60px,9vw,96px);font-weight:800;line-height:1;text-align:center}
.band .big small{display:block;font-size:15px;color:var(--mut);font-weight:600;margin-top:8px}
@media (max-width:800px){.band{grid-template-columns:1fr;padding:30px}}

/* contact */
.contacts{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:36px}
@media (max-width:760px){.contacts{grid-template-columns:1fr}}
.ct{display:flex;align-items:center;gap:14px;background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:18px 20px;transition:border-color .2s}
.ct:hover{border-color:var(--acc)}
.ct .ci{width:46px;height:46px;border-radius:12px;display:grid;place-items:center;font-size:21px;flex:none}
.ct small{display:block;color:var(--mut);font-size:12px}
.ct b{font-size:17px}

footer{border-top:1px solid var(--line);padding:34px 0 90px;color:var(--dim);font-size:13px}
footer .wrap{display:grid;gap:12px}
footer .disc{max-width:900px}

/* floating */
.fab{position:fixed;right:18px;bottom:18px;z-index:60;display:flex;flex-direction:column;gap:10px}
.fab a{width:52px;height:52px;border-radius:50%;display:grid;place-items:center;font-size:22px;box-shadow:0 10px 24px -8px rgba(0,0,0,.7)}
.fab .z{background:#0068ff;color:#fff;font-weight:800;font-size:14px}
.fab .p{background:var(--ok)}

/* modal + form */
.modal{position:fixed;inset:0;z-index:100;display:none;align-items:center;justify-content:center;padding:16px;background:rgba(3,4,7,.72);backdrop-filter:blur(4px)}
.modal.on{display:flex}
.dlg{width:100%;max-width:480px;max-height:calc(100vh - 32px);overflow:auto;background:var(--bg2);border:1px solid var(--line2);border-radius:20px;padding:28px;position:relative}
.dlg h3{font-size:22px}.dlg .sub{color:var(--mut);font-size:14px;margin:4px 0 18px}
.dlg .x{position:absolute;top:14px;right:14px;width:34px;height:34px;border-radius:10px;border:1px solid var(--line2);background:var(--panel);color:var(--txt);cursor:pointer;font-size:16px}
.f{display:grid;gap:12px}
.f label{display:grid;gap:6px;font-size:13px;color:var(--mut);font-weight:600}
.f input,.f select,.f textarea{font:inherit;font-size:15px;color:var(--txt);background:var(--panel);border:1px solid var(--line2);border-radius:11px;padding:12px 13px;width:100%;outline:none;transition:border-color .15s}
.f input:focus,.f select:focus,.f textarea:focus{border-color:var(--acc)}
.f .two-c{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.f .hp{position:absolute;left:-9999px;width:1px;height:1px;opacity:0}
.f .total{display:flex;justify-content:space-between;align-items:center;background:var(--panel);border:1px dashed var(--line2);border-radius:11px;padding:12px 14px;font-size:14px;color:var(--mut)}
.f .total b{font-size:20px;color:var(--txt)}
.msg{font-size:14px;border-radius:11px;padding:11px 13px;display:none}
.msg.on{display:block}
.msg.err{background:rgba(239,68,68,.1);border:1px solid rgba(239,68,68,.35);color:#fecaca}
.msg.ok{background:rgba(34,197,94,.1);border:1px solid rgba(34,197,94,.35);color:#c9f2d8}
.small{font-size:12px;color:var(--dim)}

/* mua / gia hạn / VietQR */
.seg{display:flex;gap:6px;background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:5px;margin:0 36px 16px 0}
.seg button{flex:1;font:inherit;font-weight:700;font-size:14px;color:var(--mut);background:none;border:0;border-radius:10px;padding:10px;cursor:pointer}
.seg button.on{background:var(--panel2);color:var(--txt);box-shadow:inset 0 0 0 1px var(--line2)}
.planbar{display:flex;align-items:center;justify-content:space-between;gap:12px;background:rgba(255,59,48,.08);border:1px solid rgba(255,59,48,.4);border-radius:14px;padding:12px 16px;margin-bottom:16px}
.planbar .pl{display:flex;align-items:center;gap:10px;font-weight:700}
.planbar .pl span{color:var(--mut);font-size:13px;font-weight:600}
.planbar select{font:inherit;font-weight:800;font-size:17px;color:var(--txt);background:transparent;border:0;outline:none;cursor:pointer}
.planbar select option{background:var(--bg2)}
.planbar b{font-size:20px;color:var(--acc2)}
.f .hint{font-weight:500;color:var(--dim)}
.f input::placeholder{text-transform:none}
.small.center{text-align:center}
.qrbox{background:#fff;border-radius:16px;padding:12px;width:max-content;max-width:100%;margin:4px auto 0}
.qrbox img{width:260px;height:auto;max-width:100%;display:block}
.amt{text-align:center;font-size:30px;font-weight:800;margin:16px 0 8px;letter-spacing:-.5px}
.kv{display:grid;margin:6px 0 14px}
.kv>div{display:flex;align-items:center;gap:10px;padding:12px 2px;border-bottom:1px solid var(--line);font-size:14px}
.kv span{color:var(--mut);flex:1}
.kv b{font-family:ui-monospace,Consolas,monospace;font-size:15px;text-align:right;word-break:break-all}
.kv b.hl{color:var(--acc2);font-size:17px;letter-spacing:1px}
.kv .cp{font:inherit;font-size:12px;font-weight:700;color:var(--txt);background:var(--panel2);border:1px solid var(--line2);border-radius:8px;padding:4px 9px;cursor:pointer}
.wait{display:flex;align-items:center;gap:10px;color:#cdd3de;font-size:14px;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:12px 14px;margin-bottom:10px}
.spin{flex:none;width:16px;height:16px;border-radius:50%;border:2px solid var(--line2);border-top-color:var(--acc);animation:spin .8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.done{text-align:center}
.done .big{font-size:54px;line-height:1}
.done h3{margin:10px 0 6px}
.done .kv{text-align:left}
.done ol.nx{text-align:left;color:#cdd3de;font-size:14px;margin:4px 0 18px 20px;display:grid;gap:6px}
.paybar{position:fixed;left:50%;bottom:18px;transform:translateX(-50%);z-index:70;display:none;align-items:center;gap:12px;background:var(--bg2);border:1px solid rgba(255,59,48,.5);border-radius:14px;padding:10px 12px 10px 16px;box-shadow:0 20px 40px -12px rgba(0,0,0,.8);font-size:14px;max-width:calc(100% - 32px)}
.paybar.on{display:flex}
.paybar .x2{background:none;border:0;color:var(--mut);cursor:pointer;font-size:14px}
@media (max-width:560px){.paybar{left:16px;right:16px;transform:none;flex-wrap:wrap}}

.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%) translateY(30px);opacity:0;z-index:120;background:#0f1a14;border:1px solid rgba(34,197,94,.45);color:#c9f2d8;padding:11px 16px;border-radius:12px;font-size:14px;transition:.25s;pointer-events:none}
.toast.on{opacity:1;transform:translateX(-50%) translateY(0)}

.reveal{opacity:0;transform:translateY(18px);transition:opacity .6s ease,transform .6s ease}
.reveal.in{opacity:1;transform:none}
@media (prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none;transition:none}html{scroll-behavior:auto}}