/* Lehia Software Company Limited — arkusz stylów / stylesheet */

:root{
  --ink:#273046;
  --ink-deep:#1a2030;
  --proporzec:#dd0f22;
  --paper:#f1f3f7;
  --body-ink:#4b5468;
  --muted:#6e7788;
  --line:rgba(39,48,70,.15);
  --line-strong:rgba(39,48,70,.32);
  --display:"Jost",sans-serif;
  --shell:min(1200px,92vw);
}
html[lang="vi"]{--display:"Be Vietnam Pro",sans-serif}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  background:var(--paper);color:var(--ink);
  font-family:"IBM Plex Sans",system-ui,sans-serif;
  font-size:16.5px;line-height:1.65;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
  display:flex;flex-direction:column;min-height:100vh;
}
img{max-width:100%;height:auto;display:block}
a{color:inherit}
main{flex:1}

.shell{width:var(--shell);margin-inline:auto}
.mono{font-family:"IBM Plex Mono",monospace;font-size:.66rem;letter-spacing:.2em;text-transform:uppercase;color:var(--muted)}
.display{font-family:var(--display);font-weight:200;line-height:1.06;letter-spacing:-.01em}

.pennant{display:inline-flex;align-items:center;gap:.7rem}
.pennant::before{content:"";width:14px;height:9px;flex:none;background:var(--proporzec);
  clip-path:polygon(0 0,100% 0,100% 100%,0 100%,28% 50%)}

/* ---------------- header ---------------- */
header{position:sticky;top:0;z-index:60;background:rgba(241,243,247,.9);
  backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.bar{display:flex;align-items:center;justify-content:space-between;gap:1.2rem;
  min-height:80px;padding:.6rem 0}
.brand{flex:none;display:block;line-height:0}
.brand img{height:44px;width:auto;max-width:none;aspect-ratio:900/444;object-fit:contain}
.bar-right{display:flex;align-items:center;gap:clamp(.8rem,2.2vw,2rem)}
nav{display:flex;gap:clamp(.9rem,1.8vw,1.9rem);align-items:center;flex-wrap:wrap;justify-content:flex-end}
nav a{font-family:"IBM Plex Mono",monospace;font-size:.68rem;letter-spacing:.15em;
  text-transform:uppercase;text-decoration:none;padding-bottom:3px;white-space:nowrap;
  border-bottom:1px solid transparent;transition:border-color .25s}
nav a:hover,nav a:focus-visible{border-bottom-color:var(--proporzec)}
nav a[aria-current="page"]{border-bottom-color:var(--ink)}

.lang{display:flex;align-items:center;border:1px solid var(--line-strong);flex:none}
.lang button{font-family:"IBM Plex Mono",monospace;font-size:.66rem;letter-spacing:.1em;
  background:none;border:0;border-right:1px solid var(--line-strong);
  padding:.5rem .6rem;cursor:pointer;color:var(--muted);transition:background .2s,color .2s}
.lang button:last-child{border-right:0}
.lang button:hover{color:var(--ink)}
.lang button[aria-current="true"]{background:var(--ink);color:var(--paper)}

/* ---------------- page head ---------------- */
.lance{position:relative;height:1px;background:var(--line-strong);transform-origin:left;margin-bottom:2.4rem}
.lance::after{content:"";position:absolute;right:0;top:-8px;width:26px;height:17px;
  background:var(--proporzec);clip-path:polygon(0 0,100% 0,100% 100%,0 100%,30% 50%)}

.hero{padding:clamp(3rem,8vw,6.5rem) 0 clamp(2.5rem,5vw,4rem)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(0,.6fr);
  gap:clamp(2rem,5vw,4rem);align-items:end}
h1{font-size:clamp(2.4rem,6vw,4.6rem)}
h1 em{font-style:normal;font-weight:400}
.page-h1{font-size:clamp(2.1rem,5vw,3.6rem)}
.lead{max-width:52ch;margin-top:1.7rem;color:var(--body-ink);font-size:1.06rem}
.hero-mark{justify-self:end}
.hero-mark img{width:clamp(120px,15vw,190px);height:auto;aspect-ratio:420/761;object-fit:contain}

.cta-row{display:flex;flex-wrap:wrap;gap:1rem;margin-top:2.4rem}
.btn{font-family:"IBM Plex Mono",monospace;font-size:.7rem;letter-spacing:.15em;
  text-transform:uppercase;text-decoration:none;padding:1.05rem 1.9rem;
  border:1px solid var(--ink);display:inline-block;
  transition:background .25s,color .25s,border-color .25s}
.btn-solid{background:var(--ink);color:var(--paper)}
.btn-solid:hover{background:var(--proporzec);border-color:var(--proporzec)}
.btn-ghost:hover{background:var(--ink);color:var(--paper)}

/* ---------------- sections ---------------- */
section{padding:clamp(3rem,6.5vw,5.5rem) 0;border-top:1px solid var(--line)}
section.plain{border-top:0}
.sec-head{display:flex;justify-content:space-between;align-items:baseline;gap:2rem;
  flex-wrap:wrap;margin-bottom:clamp(1.8rem,4vw,3rem)}
.sec-head h2{font-family:var(--display);font-weight:200;
  font-size:clamp(1.8rem,3.4vw,2.7rem);line-height:1.12}

/* ledger rows */
.row{display:grid;grid-template-columns:minmax(0,150px) minmax(0,1fr) minmax(0,1.05fr);
  gap:clamp(1.1rem,3vw,3rem);padding:2.3rem 0;border-top:1px solid var(--line);
  transition:background .3s;scroll-margin-top:100px}
.row:last-child{border-bottom:1px solid var(--line)}
.row:hover{background:rgba(255,255,255,.6)}
.row h3{font-family:var(--display);font-weight:300;font-size:1.55rem;line-height:1.22}
.row .desc{color:var(--body-ink);margin-top:.7rem;font-size:.98rem}
.row .forwho{margin-top:1rem;font-size:.88rem;color:var(--muted)}
.ticks{list-style:none;font-size:.94rem}
.ticks li{padding:.42rem 0 .42rem 1.3rem;position:relative;border-bottom:1px solid var(--line);color:var(--body-ink)}
.ticks li:last-child{border-bottom:0}
.ticks li::before{content:"";position:absolute;left:0;top:1.1em;width:7px;height:1px;background:var(--proporzec)}

/* steps */
.steps{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:1px;
  background:var(--line);border:1px solid var(--line)}
.step{background:var(--paper);padding:2rem 1.6rem 2.2rem}
.step .num{font-family:var(--display);font-weight:200;font-size:2.6rem;color:var(--line-strong);line-height:1}
.step h4{font-family:var(--display);font-weight:400;font-size:1.14rem;margin:.9rem 0 .5rem}
.step p{font-size:.92rem;color:var(--body-ink)}
.step .ticks{margin-top:1rem;font-size:.87rem}

/* two column prose */
.cols{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:clamp(2rem,5vw,4.5rem);align-items:start}
.cols p{color:var(--body-ink)}
.prose p+p{margin-top:1rem}

/* dark band */
.band{background:var(--ink-deep);color:#dfe3ec;border-top:0}
.band h2,.band h3{color:#fff}
.band .mono{color:#8e97ab}
.band p{color:#b9c0cf}
.band .stack li{padding:.85rem 0;border-top:1px solid rgba(255,255,255,.13);font-size:.97rem}
.band .stack li:last-child{border-bottom:1px solid rgba(255,255,255,.13)}
.stack{list-style:none;margin-top:1.5rem}
.stack li{padding:.85rem 0;border-top:1px solid var(--line);font-size:.97rem;color:var(--body-ink)}
.stack li:last-child{border-bottom:1px solid var(--line)}

/* definition list — rules */
.rules{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:2rem 3rem;margin-top:1rem}
.rules h4{font-family:var(--display);font-weight:400;font-size:1.15rem;margin-bottom:.5rem}
.rules p{font-size:.94rem;color:var(--body-ink)}

/* contact list */
.contact-list{list-style:none}
.contact-list li{padding:1.3rem 0;border-top:1px solid var(--line)}
.contact-list li:last-child{border-bottom:1px solid var(--line)}
.contact-list a,.contact-list .val{font-family:var(--display);font-weight:300;
  font-size:clamp(1.1rem,2.3vw,1.45rem);text-decoration:none;display:inline-block;margin-top:.3rem}
.contact-list a{border-bottom:1px solid var(--line-strong);transition:border-color .25s,color .25s}
.contact-list a:hover{color:var(--proporzec);border-bottom-color:var(--proporzec)}

/* notice box */
.notice{border:1px solid var(--proporzec);padding:1.2rem 1.4rem;margin-bottom:2rem;font-size:.93rem;background:rgba(221,15,34,.04)}

/* footer */
footer{background:var(--ink);color:#aab2c3;padding:3rem 0 2.2rem;margin-top:auto}
.foot{display:flex;justify-content:space-between;align-items:center;gap:1.5rem;flex-wrap:wrap}
.foot img{height:54px;width:auto;max-width:none;aspect-ratio:900/444;object-fit:contain}
.foot-links{display:flex;gap:1.6rem;align-items:center;flex-wrap:wrap}
.foot .mono{color:#7f889c}
.foot a{text-decoration:none;border-bottom:1px solid rgba(255,255,255,.2)}
.foot a:hover{border-bottom-color:var(--proporzec)}

/* motion */
.reveal{opacity:0;transform:translateY(18px);transition:opacity .7s ease,transform .7s ease}
.reveal.in{opacity:1;transform:none}
.lance{transform:scaleX(0);transition:transform 1.1s cubic-bezier(.2,.7,.2,1)}
.lance.in{transform:scaleX(1)}

@media (max-width:980px){
  .bar{flex-wrap:wrap;min-height:0}
  .bar-right{width:100%;justify-content:space-between}
  nav{justify-content:flex-start;gap:1.1rem}
}
@media (max-width:880px){
  .hero-grid{grid-template-columns:1fr}
  .hero-mark{justify-self:start;order:-1;margin-bottom:.5rem}
  .hero-mark img{width:104px;height:auto}
  .row{grid-template-columns:1fr;gap:1rem}
  .cols{grid-template-columns:1fr}
  .brand img{height:38px}
}
@media (max-width:520px){
  nav a{font-size:.62rem;letter-spacing:.08em}
  .foot img{height:44px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.lance{transition:none;opacity:1;transform:none}
}
:focus-visible{outline:2px solid var(--proporzec);outline-offset:3px}