/* ===== Samitra — brand site (BUTB/BUCE) ===== */
@font-face{
  font-family:'Manrope';
  src:url('../fonts/Manrope.woff2') format('woff2');
  font-weight:200 800; font-style:normal; font-display:swap;
}
@font-face{
  font-family:'JetBrains Mono';
  src:url('../fonts/JetBrainsMono.woff2') format('woff2');
  font-weight:400 800; font-style:normal; font-display:swap;
}

:root{
  --green:#265B42; --deep:#1C4632; --green2:#24503B;
  --gold:#D2AA3A; --gold3:#EBC868; --gold1:#FBE199; --cube:#C6982E;
  --graph:#202020; --paper:#F2F4F0; --card:#ffffff;
  --mute:#6B7169; --cream:#F4F1E8; --sage:#A9C1B2; --line:#E4E8E3;
  --shadow:0 14px 34px -18px rgba(16,41,29,.42);
  --shadow-sm:0 8px 20px -12px rgba(16,41,29,.34);
  --font:'Manrope',system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;
  --mono:'JetBrains Mono',ui-monospace,SFMono-Regular,Menlo,monospace;
  --maxw:1180px; --radius:16px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0; font-family:var(--font); color:var(--graph);
  background:var(--paper); line-height:1.55; -webkit-font-smoothing:antialiased;
  font-size:17px;
}
img{max-width:100%; display:block}
a{color:inherit; text-decoration:none}
h1,h2,h3,h4,p{margin:0}

/* i18n visibility (RU default) */
.i-en{display:none}
html.lang-en .i-ru{display:none}
html.lang-en .i-en{display:inline}

.container{max-width:var(--maxw); margin:0 auto; padding:0 24px}
.ic{width:1em; height:1em; fill:currentColor; flex:none}

/* ---------- header ---------- */
.site-header{
  position:fixed; inset:0 0 auto 0; z-index:50; height:70px;
  background:rgba(242,244,240,.86); backdrop-filter:saturate(1.2) blur(10px);
  border-bottom:1px solid var(--line);
}
.site-header .container{display:flex; align-items:center; gap:20px; height:100%}
.brand{display:flex; align-items:center; height:100%}
.brand img{height:34px; width:auto}
.nav{display:flex; align-items:center; gap:26px; margin-left:auto}
.nav a.navlink{
  font-size:14.5px; font-weight:600; color:var(--green); white-space:nowrap;
  padding:6px 0; border-bottom:2px solid transparent; transition:.15s;
}
.nav a.navlink:hover{border-color:var(--gold)}
.langbar{display:inline-flex; border:1px solid var(--green); border-radius:999px; overflow:hidden}
.langbar button{
  font-family:var(--mono); font-size:12px; font-weight:700; letter-spacing:.5px;
  padding:6px 11px; background:transparent; color:var(--green); border:0; cursor:pointer; transition:.15s;
}
.langbar button[aria-pressed="true"]{background:var(--green); color:var(--cream)}
.btn{
  display:inline-flex; align-items:center; gap:9px; font-weight:700; font-size:15px;
  padding:11px 20px; border-radius:999px; cursor:pointer; border:2px solid transparent; transition:.18s;
  line-height:1;
}
.btn-primary{background:var(--gold); color:var(--deep)}
.btn-primary:hover{background:var(--gold3)}
.btn-ghost{background:transparent; color:var(--cream); border-color:rgba(244,241,232,.4)}
.btn-ghost:hover{border-color:var(--gold3); color:var(--gold3)}
.btn-green{background:var(--green); color:var(--cream)}
.btn-green:hover{background:var(--deep)}
.header-cta{margin-left:2px}
.burger{display:none; margin-left:auto; background:transparent; border:0; color:var(--green); font-size:24px; cursor:pointer}

/* ---------- section scaffolding ---------- */
section{padding:92px 0; scroll-margin-top:80px}
.section-paper{background:var(--paper)}
.section-white{background:#fff}
.kicker{
  display:inline-flex; align-items:center; gap:10px; font-family:var(--mono);
  font-size:12.5px; font-weight:700; letter-spacing:2px; text-transform:uppercase; color:var(--green);
}
.kicker::before{content:""; width:11px; height:11px; border-radius:3px; background:var(--gold); flex:none}
.h2{font-size:clamp(27px,3.4vw,40px); font-weight:800; color:var(--green); letter-spacing:-.5px; margin-top:14px; line-height:1.1}
.lead{max-width:820px; margin-top:18px; color:var(--graph); font-size:18px}
.lead b{color:var(--green)}
.sec-head{margin-bottom:44px}

/* ---------- hero ---------- */
.hero{
  position:relative; background:var(--deep); color:var(--cream); overflow:hidden;
  padding:150px 0 80px; scroll-margin-top:0;
}
.hero .mark-motif{
  position:absolute; right:-60px; top:80px; width:min(46vw,540px); opacity:.10;
  filter:grayscale(.2); pointer-events:none;
}
.hero .ring{
  position:absolute; border:1.5px solid rgba(91,143,191,0); border-radius:50%;
}
.hero-inner{position:relative; max-width:840px}
.hero .kicker{color:var(--gold3)}
.hero .kicker::before{background:var(--gold)}
.hero h1{font-size:clamp(44px,6.4vw,76px); font-weight:800; letter-spacing:-1.5px; line-height:1; margin-top:20px; color:#fff}
.hero .subtitle{margin-top:22px; font-size:clamp(18px,2vw,22px); color:var(--sage); max-width:620px}
.hero .tagline{margin-top:22px; display:flex; align-items:center; gap:12px; color:var(--gold3); font-style:italic; font-weight:600; font-size:17px}
.hero .tagline::before{content:""; width:9px;height:9px;border-radius:50%;background:var(--gold); flex:none}
.hero-cta{display:flex; flex-wrap:wrap; gap:14px; margin-top:38px}
.hero-contacts{display:flex; flex-wrap:wrap; gap:26px 40px; margin-top:52px}
.hero-contacts .ci{display:flex; align-items:center; gap:12px; color:var(--cream); font-size:15px}
.ci .icon-circle{width:40px;height:40px}
.hero-contacts .mono{font-family:var(--mono); font-size:14px}

/* icon circles */
.icon-circle{
  display:inline-flex; align-items:center; justify-content:center; border-radius:50%;
  width:64px; height:64px; font-size:26px; flex:none; box-shadow:var(--shadow-sm);
}
.ic-green{background:var(--green); color:var(--gold3)}
.ic-gold{background:var(--gold); color:var(--deep)}

/* ---------- cards / grids ---------- */
.grid{display:grid; gap:22px}
.g5{grid-template-columns:repeat(5,1fr)}
.g3{grid-template-columns:repeat(3,1fr)}
.g2{grid-template-columns:repeat(2,1fr)}
.card{
  background:var(--card); border:1px solid var(--line); border-radius:var(--radius);
  padding:26px; box-shadow:var(--shadow); transition:transform .2s, box-shadow .2s;
}
.card:hover{transform:translateY(-4px); box-shadow:0 22px 44px -20px rgba(16,41,29,.5)}
.card .icon-circle{margin-bottom:18px}
.card h3{font-size:18px; font-weight:800; color:var(--green); line-height:1.15}
.card p{margin-top:10px; color:var(--mute); font-size:14.5px}

/* section cards (5) center */
.sec-card{text-align:center}
.sec-card .icon-circle{width:72px;height:72px;font-size:30px; margin:0 auto 16px}
.sec-card h3{min-height:2.3em; display:flex; align-items:flex-end; justify-content:center}

/* advantage row cards (icon left) */
.row-card{display:flex; gap:18px; align-items:flex-start; text-align:left}
.row-card .icon-circle{width:56px;height:56px;font-size:23px; margin:0}
.row-card .rc-body h3{margin-bottom:6px}

/* numbered steps (client docs) */
.step-card{position:relative; overflow:hidden}
.step-card .num{font-family:var(--mono); font-weight:800; font-size:46px; color:#E6EDE7; line-height:1}
.step-card .icon-circle{position:absolute; top:22px; right:22px; margin:0}
.step-card h3{margin-top:14px}

/* bonus callout */
.bonus{
  margin-top:24px; background:var(--green); color:var(--cream); border-radius:var(--radius);
  padding:22px 26px; display:flex; gap:18px; align-items:center; box-shadow:var(--shadow);
}
.bonus .icon-circle{width:52px;height:52px;font-size:22px; background:var(--gold); color:var(--deep)}
.bonus b{color:var(--gold3)}

/* ---------- algorithm ---------- */
.algo-legend{display:flex; gap:22px; margin:6px 0 30px; font-weight:600; color:var(--green); font-size:14.5px}
.algo-legend span{display:inline-flex; align-items:center; gap:8px}
.dot{width:13px;height:13px;border-radius:50%; display:inline-block}
.dot-b{background:var(--green)} .dot-c{background:var(--gold)}
.tracks{display:grid; grid-template-columns:1fr 1fr; gap:34px}
.track-head{
  display:flex; align-items:center; gap:12px; background:var(--green); color:var(--cream);
  border-radius:999px; padding:12px 18px; font-weight:800; font-size:17px; margin-bottom:14px;
}
.track-head .icon-circle{width:38px;height:38px;font-size:17px; background:var(--gold); color:var(--deep); box-shadow:none}
.steps{list-style:none; margin:0; padding:0}
.steps li{display:flex; align-items:center; gap:14px; padding:8px 4px; border-bottom:1px dashed var(--line)}
.steps li:last-child{border-bottom:0}
.steps .n{
  width:28px;height:28px;border-radius:50%; flex:none; display:inline-flex; align-items:center; justify-content:center;
  font-family:var(--mono); font-weight:700; font-size:12.5px;
}
.n-b{background:var(--green); color:var(--cream)}
.n-c{background:var(--gold); color:var(--deep)}
.steps li span.txt{font-size:15px}

/* guarantees (center 3) */
.guarantee{text-align:center}
.guarantee .icon-circle{width:84px;height:84px;font-size:36px; margin:0 auto 18px}
.guarantee h3{font-size:19px; margin-bottom:8px}
.guarantee p{color:var(--mute); font-size:14.5px}

/* ---------- closing / footer ---------- */
.closing{background:var(--deep); color:var(--cream); position:relative; overflow:hidden}
.closing .mark-motif{position:absolute; left:-90px; bottom:-90px; width:360px; opacity:.07}
.closing-grid{display:grid; grid-template-columns:1.15fr .85fr; gap:56px; align-items:center; position:relative}
.closing .kicker{color:var(--gold3)} .closing .kicker::before{background:var(--gold)}
.closing h2{font-size:clamp(28px,3.4vw,40px); font-weight:800; color:#fff; margin:12px 0 26px; line-height:1.1}
.pts{display:flex; flex-direction:column; gap:20px; margin-bottom:30px}
.pt{display:flex; gap:16px; align-items:flex-start}
.pt .icon-circle{width:52px;height:52px;font-size:22px; background:var(--gold); color:var(--deep)}
.pt h4{font-size:17px; font-weight:800; color:#fff}
.pt p{color:var(--sage); font-size:14.5px; margin-top:3px}
.contact-panel{background:var(--green2); border-radius:var(--radius); padding:26px 28px}
.contact-panel .kicker{color:var(--gold3); font-size:11.5px}
.clist{list-style:none; margin:16px 0 0; padding:0; display:flex; flex-direction:column; gap:12px}
.clist li{display:flex; align-items:center; gap:14px}
.clist .icon-circle{width:40px;height:40px;font-size:16px; background:var(--gold); color:var(--deep); box-shadow:none}
.clist a,.clist span{color:var(--cream); font-size:15px}
.clist .mono{font-family:var(--mono); font-size:14px; color:var(--gold3)}
.cert-wrap{background:var(--cream); border-radius:12px; padding:14px; box-shadow:0 26px 60px -24px rgba(0,0,0,.55)}
.cert-wrap img{border-radius:6px}
.cert-cap{font-family:var(--mono); font-size:11px; color:var(--sage); text-align:center; margin-top:12px}

.site-footer{background:var(--deep); color:var(--sage); border-top:1px solid rgba(255,255,255,.08); padding:26px 0}
.site-footer .container{display:flex; flex-wrap:wrap; gap:14px; align-items:center; justify-content:space-between}
.site-footer img{height:26px; opacity:.95}
.site-footer .fmeta{font-family:var(--mono); font-size:12px; letter-spacing:.5px}

/* reveal */
.reveal{opacity:0; transform:translateY(18px); transition:opacity .6s ease, transform .6s ease}
.reveal.in{opacity:1; transform:none}

/* ---------- responsive ---------- */
@media (max-width:1024px){
  .g5{grid-template-columns:repeat(3,1fr)}
}
@media (max-width:860px){
  .nav{
    position:fixed; inset:70px 0 auto 0; flex-direction:column; align-items:stretch; gap:0;
    background:var(--paper); border-bottom:1px solid var(--line); padding:8px 24px 18px;
    transform:translateY(-140%); transition:transform .28s; box-shadow:var(--shadow);
  }
  .nav.open{transform:none}
  .nav a.navlink{padding:12px 0; border-bottom:1px solid var(--line)}
  .nav .langbar,.nav .header-cta{margin-top:12px; align-self:flex-start}
  .burger{display:block}
  .g5,.g3,.g2,.tracks,.closing-grid{grid-template-columns:1fr}
  .closing-grid{gap:36px}
  .cert-wrap{max-width:420px; margin:0 auto}
  section{padding:66px 0}
  .hero{padding:120px 0 64px}
}
@media (max-width:560px){
  body{font-size:16px}
  .hero-contacts{gap:16px}
  .container{padding:0 18px}
  .card{padding:22px}
}