/* Public site. Tokens and fonts come from /theme.css (shared with the Studio). */
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--paper);color:var(--ink);font:400 16px/1.65 var(--font-ui);font-synthesis:none;text-rendering:optimizeLegibility}
a{color:var(--accent-ink);text-underline-offset:3px;text-decoration-thickness:1px}
a:hover{color:var(--accent)}
:focus-visible{outline:none;box-shadow:var(--focus);border-radius:6px}
img{max-width:100%}
.wrap{max-width:1160px;margin:0 auto;padding:0 clamp(18px,4vw,40px)}
.skip{position:absolute;left:-999px;top:8px;background:var(--ink);color:#fff;padding:8px 12px;border-radius:var(--r-sm);z-index:20}
.skip:focus{left:12px}

/* Type */
h1,h2,.display{font-family:var(--font-display);font-weight:600;color:var(--ink);text-wrap:balance;letter-spacing:-.01em}
h1{font-size:clamp(2.35rem,1.35rem + 3.6vw,4rem);line-height:1.12;margin:.5rem 0 1.25rem}
h2{font-size:clamp(1.75rem,1.25rem + 1.7vw,2.5rem);line-height:1.2;margin:0 0 .9rem}
h3{font:600 1.125rem/1.4 var(--font-ui);margin:0 0 .4rem;color:var(--ink)}
p{margin:0 0 1rem;text-wrap:pretty}
.eyebrow{font:600 .8125rem/1.4 var(--font-ui);letter-spacing:.08em;text-transform:uppercase;color:var(--accent-ink);margin:0}
.lead{font-size:clamp(1.0625rem,1rem + .3vw,1.1875rem);color:var(--ink-2);max-width:38em}
.muted{color:var(--muted)}
.small-print,.field-help{font-size:.875rem;color:var(--muted)}
.section-intro{max-width:44em;color:var(--ink-2);margin-bottom:2rem}

/* Buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;min-height:44px;border:1px solid var(--line-2);background:var(--surface);color:var(--ink);border-radius:var(--r-md);padding:.65rem 1.1rem;font:600 .9375rem/1.2 var(--font-ui);text-decoration:none;cursor:pointer;transition:background .15s,border-color .15s,color .15s}
.btn:hover{border-color:var(--ink-2);color:var(--ink)}
.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}
.btn.primary:hover{background:var(--accent-ink);border-color:var(--accent-ink);color:#fff}
.btn.large{min-height:52px;padding:.85rem 1.4rem;font-size:1rem}
.btn.small{min-height:38px;padding:.45rem .9rem;font-size:.875rem}
.btn.disabled,.btn[aria-disabled=true]{opacity:.55;cursor:default;pointer-events:none}
.ext::after{content:"";width:.7em;height:.7em;background:currentColor;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'%3E%3Cpath d='M4 2h6v6M10 2 2 10' fill='none' stroke='black' stroke-width='1.6'/%3E%3C/svg%3E") center/contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'%3E%3Cpath d='M4 2h6v6M10 2 2 10' fill='none' stroke='black' stroke-width='1.6'/%3E%3C/svg%3E") center/contain no-repeat}
.go::after{content:"";width:.9em;height:.9em;background:currentColor;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 14'%3E%3Cpath d='M1 7h11M8 3l4 4-4 4' fill='none' stroke='black' stroke-width='1.6'/%3E%3C/svg%3E") center/contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 14'%3E%3Cpath d='M1 7h11M8 3l4 4-4 4' fill='none' stroke='black' stroke-width='1.6'/%3E%3C/svg%3E") center/contain no-repeat}

/* Header */
.site-head{position:sticky;top:0;z-index:10;background:rgba(248,246,241,.92);backdrop-filter:saturate(1.2) blur(8px);border-bottom:1px solid var(--line)}
.head-row{display:flex;align-items:center;gap:1.5rem;min-height:68px}
.logo{display:flex;align-items:center;gap:.6rem;white-space:nowrap;color:var(--ink);text-decoration:none;font:500 .9375rem/1.2 var(--font-ui);margin-right:auto}
.logo b{font-weight:700}
.logo-mark{display:grid;place-items:center;width:38px;height:38px;border-radius:10px;background:var(--ink);color:var(--paper);font:600 26px/1 var(--font-display);padding-bottom:3px}
.primary-nav{display:flex;gap:1.4rem;align-items:center}
.head-row .btn{white-space:nowrap}
.primary-nav a{color:var(--ink-2);text-decoration:none;font-size:.9375rem;padding:.4rem 0;white-space:nowrap}
.primary-nav a:hover,.primary-nav a[aria-current=page]{color:var(--accent-ink)}

/* Sections */
section{padding:clamp(56px,7vw,96px) 0}
.band{background:var(--surface);border-block:1px solid var(--line)}
.hero{padding-top:clamp(40px,6vw,88px);padding-bottom:clamp(48px,6vw,80px)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(360px,.9fr);gap:clamp(32px,5vw,72px);align-items:center}
.hero h1{max-width:12.5em}
.cta{display:flex;gap:.75rem;flex-wrap:wrap;margin:1.75rem 0 1rem}
.facts{display:flex;flex-wrap:wrap;gap:.4rem 1.2rem;padding:0;margin:0;list-style:none;font-size:.875rem;color:var(--muted)}
.facts li{display:flex;align-items:center;gap:.45rem}
.facts li::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--ok)}

/* Hero specimen: real engine output */
.specimen-card{margin:0;background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);box-shadow:var(--shadow-2);padding:clamp(20px,3vw,32px)}
.spec-head{display:flex;justify-content:space-between;gap:1rem;font-size:.8125rem;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:.75rem;margin-bottom:1.25rem}
.spec-head b{color:var(--ink);font-weight:600}
.parts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr)) 28px minmax(0,1.6fr);align-items:end;gap:.6rem}
.part{text-align:center}
.part .g{display:grid;place-items:end center;height:112px;font:88px/1.1 'Rakkas Original',var(--font-display);color:var(--ink);background:var(--sunken);border-radius:var(--r-md)}
.part .g.m{color:var(--mark)}
.part small,.result small{display:block;font-size:.75rem;color:var(--muted);margin-top:.45rem;line-height:1.3;min-height:2.6em}
.arrow{align-self:center;color:var(--faint);padding-bottom:1.6rem}
.arrow::after{content:"";display:block;width:22px;height:22px;background:currentColor;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 14'%3E%3Cpath d='M1 7h11M8 3l4 4-4 4' fill='none' stroke='black' stroke-width='1.4'/%3E%3C/svg%3E") center/contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 14'%3E%3Cpath d='M1 7h11M8 3l4 4-4 4' fill='none' stroke='black' stroke-width='1.4'/%3E%3C/svg%3E") center/contain no-repeat}
.result{text-align:center}
.result .g{display:grid;place-items:end center;height:160px;font:150px/1 'Rakkas VFE Demo',var(--font-display);color:var(--accent);border:1px dashed var(--accent-line);border-radius:var(--r-md);background:linear-gradient(var(--accent-soft),var(--accent-soft)) 0 78%/100% 1px no-repeat}
.spec-word{font:clamp(30px,3.4vw,44px)/1.3 'Rakkas VFE Demo',var(--font-display);margin:1.4rem 0 .25rem;color:var(--ink)}
.spec-note{font-size:.8125rem;color:var(--muted);margin:0}

/* Showcase */
.showcase{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,460px),1fr));gap:1.25rem;margin:0 0 1.25rem}
.sc-card{background:var(--paper);border:1px solid var(--line);border-radius:var(--r-lg);padding:1.25rem;display:flex;flex-direction:column;gap:.75rem}
.sc-card header{display:flex;justify-content:space-between;align-items:baseline;gap:.75rem;flex-wrap:wrap;font-size:.9375rem}
.sc-card header span{color:var(--muted);font-size:.875rem}
.sc-row{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);padding:.9rem 1rem}
.sc-row small{display:flex;justify-content:space-between;gap:.5rem;color:var(--muted);font-size:.8125rem;margin-bottom:.35rem}
.sc-text{font-size:clamp(26px,2.6vw,34px);line-height:1.4;white-space:pre-line;overflow-wrap:anywhere;color:var(--ink)}
.sc-text .borrowed{color:var(--mark);background:var(--mark-soft);border-radius:3px}
.sc-meta{font-size:.875rem;color:var(--muted);margin:0;display:flex;gap:.4rem;align-items:center}
.sc-meta .pill{background:var(--ok-soft);color:var(--ok);font-weight:600;border-radius:99px;padding:.1rem .55rem;font-size:.8125rem}
.legend{display:flex;gap:.5rem;align-items:center;font-size:.875rem;color:var(--muted)}
.legend i{display:inline-block;width:14px;height:14px;border-radius:3px;background:var(--mark-soft);border:1px solid var(--mark)}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:0;padding:0;margin:0;list-style:none;counter-reset:s;border-top:1px solid var(--line-2)}
.steps li{counter-increment:s;padding:1.25rem 1.25rem 0 0}
.steps li::before{content:counter(s,decimal-leading-zero);display:block;font:600 1.75rem/1 var(--font-display);color:var(--accent);margin-bottom:.9rem}
.steps b{display:block;font-size:1.0625rem;margin-bottom:.35rem}
.steps span{color:var(--muted);font-size:.9375rem;display:block}

/* Trust */
.trust{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:clamp(28px,5vw,64px);align-items:start}
.gate{list-style:none;margin:0;padding:0;background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);overflow:hidden}
.gate li{display:grid;grid-template-columns:28px 1fr;gap:.5rem;padding:.85rem 1.1rem;border-top:1px solid var(--line)}
.gate li:first-child{border-top:0}
.gate li::before{content:"";width:18px;height:18px;margin-top:3px;border-radius:50%;background:var(--ok-soft) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 18 18'%3E%3Cpath d='M5 9.5l2.5 2.5L13 6.5' fill='none' stroke='%231f7a55' stroke-width='2'/%3E%3C/svg%3E") center/18px no-repeat}
.gate b{display:block;font-weight:600}
.gate span{color:var(--muted);font-size:.9375rem}

/* Grids and cards */
.grid3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1px;background:var(--line);border:1px solid var(--line);border-radius:var(--r-lg);overflow:hidden}
.grid3 article{background:var(--surface);padding:1.5rem}
.grid3 p{color:var(--muted);font-size:.9375rem;margin:0}
.two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:clamp(24px,4vw,48px);align-items:start}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:clamp(20px,2.5vw,28px)}
.card.accent{border-color:var(--accent-line);background:linear-gradient(180deg,var(--accent-soft),var(--surface) 70%)}
.card h3{font:600 1.375rem/1.3 var(--font-display)}
.tag{display:inline-block;font:600 .75rem/1.4 var(--font-ui);letter-spacing:.04em;color:var(--accent-ink);background:var(--accent-soft);border-radius:99px;padding:.15rem .6rem;margin-bottom:.6rem}
ul.checks,ul.limits{padding:0;margin:0;list-style:none}
ul.checks li,ul.limits li{padding-left:1.75rem;position:relative;margin:.55rem 0;color:var(--ink-2)}
ul.checks li::before,ul.limits li::before{content:"";position:absolute;left:0;top:.3em;width:1.05rem;height:1.05rem;border-radius:50%}
ul.checks li::before{background:var(--ok-soft) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 18 18'%3E%3Cpath d='M5 9.5l2.5 2.5L13 6.5' fill='none' stroke='%231f7a55' stroke-width='2'/%3E%3C/svg%3E") center/100% no-repeat}
ul.limits li::before{background:var(--warn-soft) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 18 18'%3E%3Cpath d='M5.5 9h7' stroke='%239a5b00' stroke-width='2'/%3E%3C/svg%3E") center/100% no-repeat}
.list-title{font:600 .8125rem/1.4 var(--font-ui);letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin:0 0 .5rem}

/* FAQ */
.faq{max-width:820px}
details{border-top:1px solid var(--line-2)}
details:last-of-type{border-bottom:1px solid var(--line-2)}
details summary{cursor:pointer;font-weight:600;font-size:1.0625rem;padding:1.05rem 2rem 1.05rem 0;list-style:none;position:relative}
details summary::-webkit-details-marker{display:none}
details summary::after{content:"";position:absolute;right:.25rem;top:50%;width:10px;height:10px;border-right:2px solid var(--muted);border-bottom:2px solid var(--muted);transform:translateY(-70%) rotate(45deg);transition:transform .15s}
details[open] summary::after{transform:translateY(-30%) rotate(-135deg)}
details p{color:var(--ink-2);margin:0 0 1.1rem;max-width:44em}

/* Misc */
.notice{background:var(--warn-soft);border:1px solid #ecd9a6;border-radius:var(--r-md);padding:.85rem 1rem;color:#5c3d00;font-size:.9375rem}
.page-narrow{max-width:800px;margin:0 auto;padding:clamp(40px,6vw,72px) clamp(18px,4vw,40px) 72px}
.page-narrow h2{margin-top:2.6rem;font-size:clamp(1.5rem,1.2rem + 1vw,1.875rem)}
.page-narrow ul:not(.checks):not(.limits){padding-left:1.2rem}
.page-narrow li{margin:.35rem 0}
.account{font:500 1rem/1.6 var(--font-ui);background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);padding:.85rem 1rem;user-select:all}
textarea{width:100%;font:.875rem/1.6 ui-monospace,Consolas,'Cascadia Mono',monospace;border:1px solid var(--line-2);border-radius:var(--r-md);padding:.9rem;background:var(--surface);color:var(--ink)}
label.field{display:block;font-weight:600;font-size:.9375rem;margin:1rem 0 .35rem}
select,input[type=text]{font:inherit;width:100%;min-height:44px;border:1px solid var(--line-2);border-radius:var(--r-md);padding:.5rem .75rem;background:var(--surface);color:var(--ink)}
.sponsor{display:inline-block;margin:6px 12px 6px 0}
.ad-slot{border:1px dashed var(--line-2);border-radius:var(--r-md);padding:.75rem;margin:0 auto;max-width:970px}
.ad-slot::before{content:"Quảng cáo";display:block;font-size:.75rem;color:var(--faint);margin-bottom:.4rem}
.site-foot{border-top:1px solid var(--line);padding:2.5rem 0 3rem;font-size:.875rem;color:var(--muted)}
.foot-grid{display:flex;flex-wrap:wrap;justify-content:space-between;gap:1rem 2rem}
.foot-links{display:flex;flex-wrap:wrap;gap:.4rem 1.25rem}
.foot-links a{color:var(--ink-2)}

@media (max-width:1000px){
  .steps{grid-template-columns:repeat(3,minmax(0,1fr));row-gap:1.5rem}
  .grid3{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:860px){
  .hero-grid,.two,.trust{grid-template-columns:1fr}
  .specimen-card{max-width:520px}
}
@media (max-width:900px){
  .head-row{flex-wrap:wrap;gap:.25rem .75rem;padding-top:.6rem}
  .primary-nav{order:3;width:100%;overflow-x:auto;gap:1.1rem;padding-bottom:.35rem;scrollbar-width:none;margin:0 calc(-1*clamp(18px,4vw,40px));padding-inline:clamp(18px,4vw,40px)}
  .primary-nav::-webkit-scrollbar{display:none}
  .head-row .btn.small{min-height:36px}
}
@media (max-width:760px){
  .steps{grid-template-columns:1fr;border-top:0}
  .steps li{display:grid;grid-template-columns:3rem 1fr;padding:1rem 0;border-top:1px solid var(--line)}
  .steps li::before{grid-row:span 2;margin:0}
  .grid3{grid-template-columns:1fr}
  .parts{grid-template-columns:repeat(3,1fr);row-gap:1rem}
  .arrow{display:none}
  .result{grid-column:1/-1}
  .part .g{height:96px;font-size:76px}
  .result .g{height:150px;font-size:140px}
  .cta .btn{flex:1 1 auto}
}
@media (max-width:420px){
  .logo{font-size:.8125rem;gap:.45rem}
  .logo-mark{width:32px;height:32px;font-size:22px;border-radius:8px}
  .head-row .btn.small{padding:.4rem .7rem}
  .primary-nav{-webkit-mask:linear-gradient(90deg,#000 85%,transparent);mask:linear-gradient(90deg,#000 85%,transparent)}
}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}

/* Demo fonts (SIL OFL): the original Rakkas and the Vietnamese version built by the Studio engine. */
@font-face{font-family:'Rakkas Original';src:url(/showcase/rakkas-original.woff2) format('woff2');font-display:swap}
@font-face{font-family:'Rakkas VFE Demo';src:url(/showcase/rakkas-vn.woff2) format('woff2');font-display:swap}

/* Support page */
.donate-card{position:relative;background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);padding:clamp(20px,3vw,36px);overflow:hidden}
.donate-card::before{content:"";position:absolute;inset:0 0 auto 0;height:4px;background:linear-gradient(90deg,var(--accent),var(--mark))}
.donate-grid{display:flex;flex-wrap:wrap;gap:clamp(1.25rem,4vw,3rem);align-items:center}
.donate-qr-wrap{margin:0;flex:0 0 auto;text-align:center;font-size:.8125rem;color:var(--muted)}
.donate-qr{display:block;width:clamp(200px,28vw,260px);height:auto;background:#fff;border:1px solid var(--line);border-radius:var(--r-md);padding:10px;box-shadow:var(--shadow-2)}
.donate-qr-wrap figcaption{margin-top:.6rem}
.donate-info{flex:1 1 280px;min-width:0}
.donate-info h3{font:600 clamp(1.35rem,2.4vw,1.75rem)/1.25 var(--font-display);margin:.35rem 0 .9rem}
.donate-steps{margin:0 0 1.2rem;padding-left:1.25rem;color:var(--ink-2)}
.donate-steps li{margin:.35rem 0;padding-left:.2rem}
.donate-steps li::marker{color:var(--accent);font-weight:700}
.ref-code{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem .75rem;margin:0 0 1rem;padding:.7rem .9rem;border:1px dashed var(--accent-line);border-radius:var(--r-md);background:var(--surface)}
.ref-code span{font-size:.8125rem;color:var(--muted)}
.ref-code code{font:700 1.05rem/1 ui-monospace,Consolas,'Cascadia Mono',monospace;letter-spacing:.06em;color:var(--accent-ink)}
.ref-code .btn{margin-left:auto}
.kv{display:grid;grid-template-columns:8.5rem 1fr auto;gap:.75rem;align-items:center;padding:.6rem 0;border-bottom:1px solid var(--line)}
.kv span{color:var(--muted);font-size:.875rem}
.kv b{font-weight:600;overflow-wrap:anywhere}
.card .notice{margin:0}
@media (max-width:520px){.kv{grid-template-columns:1fr auto}.kv span{grid-column:1/-1}}