:root{
  --night:#050A1C;--deep:#0A1636;--panel:#0E1E48;--line:#1F3A7A;
  --ice:#4CC9FF;--ice-2:#9BE3FF;--volt:#1F6BFF;--gold:#E9C46A;--gold-2:#F7E1A0;
  --frost:#EAF4FF;--mute:#8FA6CF;--sale:#FF5C7A;--ok:#4ADE80;
  --d:"Chakra Petch",system-ui,sans-serif;--b:"Be Vietnam Pro",system-ui,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:
  radial-gradient(60% 50% at 80% -5%,rgba(31,107,255,.28),transparent 70%),
  radial-gradient(45% 40% at 0% 100%,rgba(76,201,255,.12),transparent 70%),var(--night);
  color:var(--frost);font:400 15px/1.6 var(--b);-webkit-font-smoothing:antialiased;overflow-x:hidden}
img{max-width:100%;display:block}
a{color:inherit}
button{font:inherit;cursor:pointer}
:focus-visible{outline:2px solid var(--ice);outline-offset:2px}
.wrap{width:min(1180px,100% - 32px);margin-inline:auto}
.muted{color:var(--mute)}
[hidden]{display:none!important}
.cut{clip-path:polygon(16px 0,100% 0,100% calc(100% - 16px),calc(100% - 16px) 100%,0 100%,0 16px)}

.btn{border:0;padding:10px 18px;font-weight:600;font-size:14px;color:var(--frost);background:none;
  clip-path:polygon(8px 0,100% 0,100% calc(100% - 8px),calc(100% - 8px) 100%,0 100%,0 8px);transition:filter .15s,background .15s}
.btn:hover{filter:brightness(1.12)}
.btn-ice{background:linear-gradient(180deg,var(--ice),var(--volt));color:#03112e}
.btn-gold{background:linear-gradient(180deg,var(--gold-2),var(--gold));color:#2a1d00}
.btn-ghost{background:rgba(76,201,255,.08);box-shadow:inset 0 0 0 1px var(--line)}
.btn-ghost:hover{background:rgba(76,201,255,.16)}
.btn-link{background:none;border:0;color:var(--mute);padding:4px 2px;text-decoration:underline;text-underline-offset:3px;clip-path:none}
.btn-link:hover{color:var(--frost)}
.btn.full{width:100%;padding:13px}
.btn-lg{display:inline-block;padding:14px 32px;font-size:16px;text-decoration:none}

/* header */
.topbar{position:sticky;top:0;z-index:40;background:rgba(5,10,28,.86);backdrop-filter:blur(10px);border-bottom:1px solid rgba(31,58,122,.6)}
.topbar-in{display:flex;align-items:center;gap:26px;height:70px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font:700 22px/1 var(--d);letter-spacing:.5px}
.brand img{border-radius:50%;box-shadow:0 0 0 2px var(--line),0 0 18px rgba(76,201,255,.4)}
.brand b{color:var(--ice)}
.nav{display:flex;gap:24px;margin-right:auto}
.nav a{text-decoration:none;color:var(--mute);font-weight:500;font-size:14.5px}
.nav a:hover{color:var(--frost)}
.account{display:flex;align-items:center;gap:10px}
.account .uname{font-weight:600;color:var(--ice-2);font-size:14px}
.menu-btn{display:none;background:none;border:0;padding:8px;flex-direction:column;gap:5px}
.menu-btn span{width:22px;height:2px;background:var(--frost);display:block}

/* hero */
.hero{overflow:hidden}
.hero-in{display:grid;grid-template-columns:1.05fr .95fr;align-items:center;gap:40px;padding:60px 0 44px}
.eyebrow{display:inline-block;font:600 12.5px var(--b);letter-spacing:1.5px;text-transform:uppercase;color:var(--ice);margin-bottom:12px}
.hero h1{font:700 clamp(32px,5vw,58px)/1.06 var(--d);margin:0 0 16px;letter-spacing:-.5px;
  background:linear-gradient(180deg,#fff 30%,var(--ice-2));-webkit-background-clip:text;background-clip:text;color:transparent}
.lead{color:#C4D4F0;font-size:17px;max-width:52ch;margin:0 0 26px}
.trust{list-style:none;padding:0;margin:26px 0 0;display:flex;flex-wrap:wrap;gap:10px 26px;color:#C4D4F0;font-size:14px}
.trust li{display:flex;align-items:center;gap:8px}
.trust svg{width:20px;height:20px;fill:var(--ice)}
.hero-art{position:relative;justify-self:center;width:min(440px,100%);aspect-ratio:1}
.hero-logo{position:relative;z-index:2;width:100%;height:100%;border-radius:50%;object-fit:cover;
  box-shadow:0 0 0 3px rgba(76,201,255,.4),0 0 90px rgba(31,107,255,.55);animation:float 6s ease-in-out infinite}
.shard{position:absolute;z-index:1;background:linear-gradient(160deg,var(--ice-2),var(--volt));opacity:.5;clip-path:polygon(50% 0,100% 40%,60% 100%,0 55%)}
.s1{width:70px;height:110px;top:-4%;left:-3%;transform:rotate(-18deg)}
.s2{width:46px;height:80px;bottom:4%;right:-5%;transform:rotate(22deg)}
.s3{width:30px;height:52px;top:12%;right:3%;opacity:.35}
@keyframes float{50%{transform:translateY(-10px)}}

/* sections */
.section{padding:52px 0 8px}
.h2{font:700 28px/1.2 var(--d);margin:0 0 24px;display:flex;align-items:center;gap:14px}
.h2::before{content:"";width:10px;height:22px;background:linear-gradient(var(--ice),var(--volt));clip-path:polygon(50% 0,100% 30%,100% 100%,0 100%,0 30%)}

/* buy */
.buy-wrap{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:20px;align-items:start}
.panel{padding:26px 24px 22px;background:linear-gradient(180deg,var(--panel),var(--deep));box-shadow:inset 0 0 0 1px var(--line)}
.panel form,#payStep{display:flex;flex-direction:column;gap:16px}
.panel-title{font:700 24px/1.15 var(--d);margin:0}
.panel-desc{margin:-8px 0 0;color:var(--mute);font-size:14px}
.note{font-size:12.5px;color:var(--mute);margin:0}
.note.center{text-align:center}
.lbl{font-size:13px;color:var(--mute);font-weight:500}
.field{display:flex;flex-direction:column;gap:7px;font-size:13px;color:var(--mute);font-weight:500}
.field input{background:var(--night);color:var(--frost);border:1px solid var(--line);padding:11px 13px;font:inherit;font-size:15px;width:100%}
.field input:focus{border-color:var(--ice);outline:none}
.pkgs{border:0;padding:0;margin:0;display:grid;gap:8px}
.pkg{position:relative;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:4px 12px;padding:12px 14px;cursor:pointer;background:rgba(5,10,28,.55);box-shadow:inset 0 0 0 1px var(--line)}
.pkg:has(input:checked){box-shadow:inset 0 0 0 2px var(--ice);background:rgba(76,201,255,.08)}
.pkg input{accent-color:var(--ice);width:18px;height:18px;margin:0}
.pkg-name{font:700 16px var(--d)}
.pkg-price{font:700 17px var(--d);color:var(--gold);text-align:right}
.pkg-stock{grid-column:2/4;font-size:12.5px;color:var(--mute)}
.pkg-note{grid-column:2/4;font-size:12.5px;color:#C4D4F0}
.pkg.out{opacity:.45;cursor:not-allowed}
.qty{display:flex;align-items:center}
.qty button{width:42px;height:44px;border:1px solid var(--line);background:var(--night);color:var(--frost);font-size:20px}
.qty button:hover{background:var(--panel)}
.qty input{width:74px;height:44px;text-align:center;border:1px solid var(--line);border-inline:0;background:var(--night);color:var(--frost);font:600 16px var(--d);-moz-appearance:textfield;appearance:textfield}
.qty input::-webkit-inner-spin-button,.qty input::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}
.qty .stock{margin-left:12px;font-size:12.5px;color:var(--mute)}
.total{display:flex;justify-content:space-between;align-items:baseline;padding:12px 0 2px;border-top:1px solid var(--line)}
.total span{color:var(--mute);font-size:14px}
.total b{font:700 26px var(--d);color:var(--gold)}
.form-err{color:var(--sale);font-size:13.5px;margin:0}
.back{align-self:flex-start;background:none;border:0;color:var(--ice);padding:0;font-weight:600}
.qrbox{align-self:center;background:#fff;padding:10px;display:grid;place-items:center}
.qrbox img{width:260px;height:auto;max-width:100%}
.bankinfo{display:grid;grid-template-columns:auto 1fr;gap:7px 16px;margin:0;font-size:14px}
.bankinfo dt{color:var(--mute)}
.bankinfo dd{margin:0;font-weight:600;min-width:0;overflow-wrap:anywhere}
.bankinfo b{color:var(--gold)}
.cpy{display:inline;background:none;border:0;padding:0;color:var(--frost);font:inherit;font-weight:600;border-bottom:1px dashed var(--mute);cursor:copy}
.cpy.gold{color:var(--gold)}
.waiting{display:flex;align-items:center;gap:10px;padding:12px 14px;font-size:14px;color:#C4D4F0;background:rgba(5,10,28,.6);box-shadow:inset 0 0 0 1px var(--line)}
.waiting .dot{flex:none;width:10px;height:10px;border-radius:50%;background:var(--gold);animation:blink 1.2s ease-in-out infinite}
@keyframes blink{50%{opacity:.25}}
.creds{display:grid;gap:8px;padding:14px;background:rgba(76,201,255,.08);box-shadow:inset 0 0 0 1px var(--ice);font-size:14px}
.creds.ok{box-shadow:inset 0 0 0 1px var(--ok);background:rgba(74,222,128,.08)}
.creds .btn{text-align:center;text-decoration:none}

/* side */
.side{padding:22px 22px;background:linear-gradient(180deg,var(--panel),var(--deep));box-shadow:inset 0 0 0 1px var(--line);position:sticky;top:88px}
.side h3{font:700 18px var(--d);margin:0 0 14px}
.feat{list-style:none;margin:0 0 16px;padding:0;display:grid;gap:14px}
.feat li{display:grid;gap:2px}
.feat b{font:600 15px var(--b)}
.feat span{font-size:13.5px;color:var(--mute)}

/* steps */
.steps{list-style:none;counter-reset:s;padding:0;margin:0;display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.steps li{counter-increment:s;position:relative;padding:22px 22px 22px 74px;background:var(--deep);box-shadow:inset 0 0 0 1px var(--line)}
.steps li::before{content:counter(s);position:absolute;left:20px;top:20px;width:40px;height:40px;display:grid;place-items:center;font:700 20px var(--d);color:var(--night);background:linear-gradient(var(--gold-2),var(--gold));clip-path:polygon(50% 0,100% 25%,100% 75%,50% 100%,0 75%,0 25%)}
.steps h3{margin:0 0 6px;font:700 17px var(--d)}
.steps p{margin:0;color:var(--mute);font-size:14px}

/* footer */
.footer{margin-top:64px;border-top:1px solid var(--line);background:var(--deep);padding:40px 0 20px}
.footer-in{display:grid;grid-template-columns:2fr 1fr 1fr;gap:32px}
.footer .brand{font-size:19px;margin-bottom:12px}
.footer p{font-size:14px;max-width:44ch;margin:0}
.footer h4{font:700 15px var(--d);margin:0 0 10px}
.footer ul{list-style:none;margin:0;padding:0;display:grid;gap:6px;font-size:14px}
.footer ul a{color:var(--mute);text-decoration:none}
.footer ul a:hover{color:var(--frost)}
.copy{font-size:13px;color:var(--mute);margin-top:28px!important;padding-top:16px;border-top:1px solid rgba(31,58,122,.5)}
.float-support{position:fixed;right:20px;bottom:20px;z-index:30;width:54px;height:54px;display:grid;place-items:center;background:linear-gradient(var(--ice),var(--volt));clip-path:polygon(50% 0,100% 25%,100% 75%,50% 100%,0 75%,0 25%)}
.float-support svg{width:24px;height:24px;fill:#03112e}

/* modals */
.modal{border:0;padding:0;background:none;color:var(--frost);max-width:calc(100% - 24px)}
.modal::backdrop{background:rgba(2,5,16,.75);backdrop-filter:blur(3px)}
.modal[open] .modal-box{animation:pop .18s ease-out}
@keyframes pop{from{opacity:0;transform:translateY(8px)}}
.modal-box{position:relative;width:420px;max-width:100%;padding:28px 24px 22px;background:linear-gradient(180deg,var(--panel),var(--deep));box-shadow:inset 0 0 0 1px var(--line);display:flex;flex-direction:column;gap:14px}
.modal-box.wide{width:720px}
.x{position:absolute;top:8px;right:10px;background:none;border:0;color:var(--mute);font-size:26px;line-height:1;padding:4px 8px}
.x:hover{color:var(--frost)}
.modal-title{font:700 22px var(--d);margin:0}
.tabs{display:flex;box-shadow:inset 0 -1px 0 var(--line)}
.tab{flex:1;background:none;border:0;color:var(--mute);padding:10px;font-weight:600;border-bottom:2px solid transparent}
.tab.on{color:var(--frost);border-color:var(--ice)}
.otable{width:100%;border-collapse:collapse;font-size:13.5px}
.otable th,.otable td{text-align:left;padding:9px 8px;border-bottom:1px solid var(--line)}
.otable th{color:var(--mute);font-weight:500;font-size:12px}
.otable code{color:var(--ice-2);font-family:var(--d)}
.pill{display:inline-block;font-size:11.5px;font-weight:600;padding:2px 8px;white-space:nowrap}
.pill.done{background:rgba(74,222,128,.15);color:var(--ok)}
.pill.paid{background:rgba(76,201,255,.15);color:var(--ice)}
.pill.wait{background:rgba(233,196,106,.15);color:var(--gold)}

.toast{position:fixed;left:50%;bottom:24px;transform:translate(-50%,20px);opacity:0;z-index:100;pointer-events:none;background:var(--frost);color:var(--night);font-weight:600;padding:12px 20px;transition:.2s;max-width:calc(100% - 32px)}
.toast.show{opacity:1;transform:translate(-50%,0)}

@media (max-width:900px){
  .menu-btn{display:flex}
  .nav{position:absolute;top:70px;left:0;right:0;flex-direction:column;gap:0;background:var(--deep);border-bottom:1px solid var(--line);display:none}
  .nav.open{display:flex}
  .nav a{padding:14px 16px;border-top:1px solid rgba(31,58,122,.5)}
  .account .btn-ghost,.account .uname{display:none}
  .hero-in{grid-template-columns:1fr;padding:34px 0 28px;gap:26px}
  .hero-art{order:-1;width:min(230px,66%)}
  .buy-wrap{grid-template-columns:1fr}
  .side{position:static}
  .steps{grid-template-columns:1fr}
  .footer-in{grid-template-columns:1fr 1fr}
  .footer-in>div:first-child{grid-column:1/-1}
}
@media (max-width:520px){
  .brand span{font-size:18px}
  .modal-box.wide{overflow-x:auto}
}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}html{scroll-behavior:auto}}

/* ---- ví số dư ---- */
.bal{display:flex;align-items:center;gap:6px;border:0;padding:7px 11px;font:inherit;font-size:13px;color:var(--mute);background:rgba(233,196,106,.1);box-shadow:inset 0 0 0 1px rgba(233,196,106,.45);cursor:pointer}
.bal b{font:700 15px var(--d);color:var(--gold)}
.bal:hover{background:rgba(233,196,106,.18)}
.gold{color:var(--gold)}
.pay-btns{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.pay-btns .btn.full{padding:13px 8px}
.pay-btns.one{grid-template-columns:1fr}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{border:0;padding:8px 12px;font:600 14px var(--d);color:var(--frost);background:rgba(76,201,255,.08);box-shadow:inset 0 0 0 1px var(--line);cursor:pointer}
.chip.on,.chip:hover{box-shadow:inset 0 0 0 1px var(--gold);color:var(--gold)}
.topup-form,.topup-pay{display:flex;flex-direction:column;gap:12px}
.topup-pay .qrbox img{width:240px}
.wallet-head{display:flex;justify-content:space-between;align-items:flex-end;gap:12px;flex-wrap:wrap;padding-right:28px}
.wallet-bal{font:700 28px var(--d);color:var(--gold);line-height:1.2}
.wallet-acts{display:flex;align-items:center;gap:12px}
.amt-plus{color:var(--ok);font-weight:600;white-space:nowrap}
.amt-minus{color:var(--sale);font-weight:600;white-space:nowrap}
.pill.ref{background:rgba(143,166,207,.15);color:var(--mute)}
@media (max-width:520px){
  .account{gap:6px}
  .account #logout{display:none}
  .account .bal{padding:6px 8px}
  .account .lbl-sd{display:none}
  .account #topupBtn{padding:7px 12px}
  .account .bal,.account #topupBtn{white-space:nowrap}
  .pay-btns{grid-template-columns:1fr}
}
.btn.dim{opacity:.65}
.form-err .btn-link{color:var(--gold);font:inherit;font-weight:600;cursor:pointer;padding:0}
@media (max-width:400px){
  .topbar .brand span{font-size:16px}
  .topbar .brand img{width:38px;height:38px}
}
@media (max-width:420px){ .account #topupBtn{display:none} .account .bal::after{content:"+";font:700 15px var(--d);color:var(--gold);margin-left:2px} }
@media (max-width:340px){ .topbar .brand span{display:none} }