/* ==========================================================================
   НСВ / DVINA — Landing stylesheet
   Design tokens sourced from client palette (navy → foam gradient).
   Typography: Nunito Sans (workhorse) + Great Vibes (single wordmark use).
   ========================================================================== */

:root{
  /* ---- palette (client-supplied) ---- */
  --c-abyss:  #06141B;   /* deepest canvas */
  --c-hull:   #11212D;   /* primary dark surface */
  --c-slate:  #253745;   /* secondary surface / borders */
  --c-steel:  #4A5C6A;   /* muted graphics, dividers */
  --c-mist:   #9BA8AB;   /* secondary text on dark */
  --c-foam:   #CCD0CF;   /* primary text on dark / light surfaces */

  /* restrained interactive accent — nudged from the same navy-slate family */
  --c-accent: #6E93A8;
  --c-accent-dim: #4A6E80;

  /* ---- semantic ---- */
  --bg: var(--c-abyss);
  --ink-hi: var(--c-foam);
  --ink-mid: var(--c-mist);
  --ink-lo: #7E93A0;   /* muted text — lightened from c-steel for AA contrast on dark bg */

  --glass-fill: rgba(17, 33, 45, 0.46);
  --glass-fill-strong: rgba(11, 24, 33, 0.62);
  --glass-fill-light: rgba(204, 208, 207, 0.08);
  --glass-border: rgba(204, 208, 207, 0.14);
  --glass-border-strong: rgba(204, 208, 207, 0.24);
  --glass-blur: 22px;

  --radius-xl: 32px;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;

  --gutter: clamp(20px, 5vw, 64px);
  --content-max: 1240px;

  --ease-out: cubic-bezier(.16,.8,.24,1);
  --ease-inout: cubic-bezier(.65,0,.35,1);

  --font-body: 'Nunito Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-script: 'Great Vibes', cursive;
}

*, *::before, *::after{ box-sizing: border-box; }

html{
  background: var(--bg);
  scroll-behavior: smooth;
  overflow-x: clip;
}

@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior: auto; }
  *{ animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; scroll-behavior: auto !important; }
}

body{
  margin: 0;
  background: var(--bg);
  color: var(--ink-hi);
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

img{ max-width: 100%; display: block; }
a{ color: inherit; text-decoration: none; }
ul, ol{ margin: 0; padding: 0; list-style: none; }
p{ margin: 0 0 1em; }
h1,h2,h3,h4,h5{ margin: 0; font-weight: 800; letter-spacing: -0.02em; }
svg{ display:block; }

/* film-grain / vignette canvas layer — quiet ambient texture over the whole page */
.grain{
  position: fixed; inset: 0; pointer-events: none; z-index: 2;
  background-image: radial-gradient(ellipse at 50% -10%, rgba(74,92,106,0.16), transparent 60%),
                     radial-gradient(ellipse at 100% 100%, rgba(6,20,27,0.5), transparent 55%);
  mix-blend-mode: normal;
}

.wrap{
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.section{
  position: relative;
  padding: clamp(72px, 11vw, 140px) 0;
}
.section--tight{ padding: clamp(28px, 5vw, 56px) 0; }
.section--dark-panel{
  background:
    radial-gradient(ellipse 60% 50% at 15% 0%, rgba(37,55,69,0.55), transparent 60%),
    linear-gradient(180deg, var(--c-hull), var(--c-abyss));
  border-top: 1px solid var(--glass-border);
  border-bottom: 1px solid var(--glass-border);
}

/* ---------------------------------------------------------------- */
/* Type scale                                                        */
/* ---------------------------------------------------------------- */
.eyebrow{
  display: flex; align-items: center; gap: 12px;
  font-size: 12.5px; font-weight: 800; letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--ink-mid);
  margin-bottom: 20px;
}
.eyebrow__line{ width: 28px; height: 1.5px; background: var(--c-accent); display:inline-block; }
.eyebrow--light{ color: rgba(204,208,207,0.75); }

.h2{
  font-size: clamp(30px, 4.4vw, 52px);
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--ink-hi);
  max-width: 16ch;
  margin-bottom: 24px;
}
.h2--sm{ font-size: clamp(26px, 3.2vw, 38px); max-width: 20ch; margin-bottom: 20px; }

.lede{
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.65;
  font-weight: 400;
  color: var(--ink-mid);
  max-width: 62ch;
  margin-bottom: 8px;
}
.lede--narrow{ max-width: 56ch; }
.lede--statement{
  color: var(--ink-hi);
  font-weight: 700;
  font-size: clamp(19px, 2vw, 24px);
  max-width: 30ch;
  margin-top: 28px;
  letter-spacing: -0.01em;
}

.muted-note{ color: var(--ink-lo); font-size: 14.5px; line-height: 1.6; }

.check-list{ display:flex; flex-direction:column; gap: 12px; margin: 20px 0; }
.check-list li{
  position: relative; padding-left: 30px; color: var(--ink-hi); font-weight: 600; font-size: 15px;
}
.check-list li::before{
  content:""; position:absolute; left:0; top: 3px; width: 18px; height: 18px; border-radius: 50%;
  background: rgba(110,147,168,0.16); border: 1px solid var(--c-accent);
}
.check-list li::after{
  content:""; position:absolute; left: 5px; top: 8px; width: 8px; height: 4px;
  border-left: 1.6px solid var(--c-accent); border-bottom: 1.6px solid var(--c-accent);
  transform: rotate(-45deg);
}
.check-list--light li{ color: var(--c-foam); }

/* ---------------------------------------------------------------- */
/* Buttons                                                            */
/* ---------------------------------------------------------------- */
.btn{
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 28px; border-radius: 999px;
  font-weight: 800; font-size: 14.5px; letter-spacing: 0.01em;
  cursor: pointer; border: 1px solid transparent;
  transition: transform .35s var(--ease-out), background .35s, border-color .35s, box-shadow .35s;
  white-space: nowrap;
}
.btn:hover{ transform: translateY(-2px); }
.btn--solid{
  background: var(--c-foam); color: var(--c-abyss);
  box-shadow: 0 8px 24px rgba(0,0,0,0.28);
}
.btn--solid:hover{ background: #fff; }
.btn--ghost-light{
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.28);
  color: var(--c-foam);
  backdrop-filter: blur(10px);
}
.btn--ghost-light:hover{ background: rgba(255,255,255,0.14); border-color: rgba(255,255,255,0.5); }

/* ---------------------------------------------------------------- */
/* Glass primitives                                                   */
/* ---------------------------------------------------------------- */
.glass-card{
  position: relative;
  background: var(--glass-fill);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  box-shadow: 0 1px 0 0 rgba(255,255,255,0.06) inset, 0 24px 48px -24px rgba(0,0,0,0.5);
}
.glass-card::before{
  content:"";
  position:absolute; inset:0; border-radius: inherit; pointer-events:none;
  background: linear-gradient(155deg, rgba(255,255,255,0.10), rgba(255,255,255,0) 40%);
}

/* focus visibility */
a:focus-visible, button:focus-visible{
  outline: 2px solid var(--c-accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ==========================================================================
   NAVIGATION — persistent glass header (revealed during reel 2)
   ========================================================================== */
.site-nav{
  --nav-o: 0;
  position: fixed; top: 0; left: 0; right: 0; z-index: 60;
  opacity: var(--nav-o);
  transform: translateX(calc((1 - var(--nav-o)) * -56px));
  pointer-events: none;
  transition: background .4s, border-color .4s, box-shadow .4s;
}
.site-nav.is-visible{ pointer-events: auto; }
.site-nav.is-solid{
  background: rgba(6, 20, 27, 0.56);
  backdrop-filter: blur(18px) saturate(140%);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  border-bottom: 1px solid var(--glass-border);
}
.site-nav__inner{
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 16px var(--gutter);
  display: flex; align-items: center; gap: 28px;
}
.site-nav__brand{ display:flex; align-items:center; gap:10px; margin-right: auto; }
.site-nav__mark{ width: 190px; height: auto; opacity: .95; }
.site-nav__brandtext{ font-weight: 800; font-size: 15px; letter-spacing: 0.01em; color: var(--c-foam); }
.site-nav__dot{ color: var(--c-accent); margin: 0 2px; }

.site-nav__links{ display:flex; align-items:center; gap: 30px; }
.site-nav__links a{
  display:flex; align-items:baseline; gap:6px;
  font-size: 13.5px; font-weight: 700; color: var(--ink-mid);
  transition: color .25s;
}
.site-nav__links a .num{ font-size: 10px; font-weight: 800; color: var(--c-accent); opacity:.85; }
.site-nav__links a:hover{ color: var(--c-foam); }

.site-nav__cta{
  padding: 10px 20px; border-radius: 999px;
  border: 1px solid var(--glass-border-strong);
  font-size: 13px; font-weight: 800; color: var(--c-foam);
  background: rgba(255,255,255,0.05);
  transition: background .25s, border-color .25s;
}
.site-nav__cta:hover{ background: rgba(255,255,255,0.14); border-color: rgba(255,255,255,0.4); }

.site-nav__burger{
  display:none; width: 40px; height: 40px; border-radius: 50%;
  border: 1px solid var(--glass-border-strong); background: rgba(255,255,255,0.05);
  align-items:center; justify-content:center; flex-direction:column; gap:4px;
  cursor:pointer;
}
.site-nav__burger span{ width: 16px; height: 1.6px; background: var(--c-foam); border-radius: 2px; transition: transform .3s, opacity .3s; }
.site-nav__burger[aria-expanded="true"] span:nth-child(1){ transform: translateY(5.6px) rotate(45deg); }
.site-nav__burger[aria-expanded="true"] span:nth-child(2){ opacity: 0; }
.site-nav__burger[aria-expanded="true"] span:nth-child(3){ transform: translateY(-5.6px) rotate(-45deg); }

.mobile-sheet{
  position: fixed; inset: 0; z-index: 59;
  background: rgba(6,20,27,0.86);
  backdrop-filter: blur(24px) saturate(140%);
  -webkit-backdrop-filter: blur(24px) saturate(140%);
  display: flex; flex-direction: column; justify-content: center; gap: 48px;
  padding: 100px var(--gutter) 60px;
  opacity: 0; visibility: hidden; transform: translateY(-8px);
  transition: opacity .35s var(--ease-out), transform .35s var(--ease-out), visibility 0s linear .35s;
}
.mobile-sheet.is-open{ opacity: 1; visibility: visible; transform: translateY(0); transition: opacity .35s var(--ease-out), transform .35s var(--ease-out); }
.mobile-sheet__links{ display:flex; flex-direction:column; gap: 26px; }
.mobile-sheet__links a{ display:flex; align-items:baseline; gap:14px; font-size: 30px; font-weight: 800; color: var(--c-foam); letter-spacing: -0.02em; }
.mobile-sheet__links a .num{ font-size: 13px; color: var(--c-accent); font-weight: 800; }
.mobile-sheet__contacts{ display:flex; flex-direction:column; gap: 10px; padding-top: 24px; border-top: 1px solid var(--glass-border); }
.mobile-sheet__contacts a{ color: var(--ink-mid); font-weight: 700; font-size: 15px; }

/* ==========================================================================
   REELS — pinned scroll-scrubbed video sections
   ========================================================================== */
.reel{
  position: relative;
  height: 260vh;
  height: calc(var(--vh, 1vh) * 260);
}
.reel--hero{ height: 340vh; height: calc(var(--vh, 1vh) * 340); }
.reel--usv{ height: 190vh; height: calc(var(--vh, 1vh) * 190); }

.reel__sticky{
  position: sticky; top: 0;
  height: 100vh; height: calc(var(--vh, 1vh) * 100); width: 100%;
  overflow: hidden;
  background: var(--c-abyss);
}
.reel__video{
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  object-position: center;
}
.reel__scrim{
  position: absolute; inset: 0;
  background:
    linear-gradient(90deg, rgba(6,14,19,0.55) 0%, rgba(6,14,19,0.05) 42%, rgba(6,14,19,0.0) 60%),
    linear-gradient(0deg, rgba(6,14,19,0.7) 0%, rgba(6,14,19,0.05) 26%, rgba(6,14,19,0) 55%);
  pointer-events: none;
}
.reel__scrim--soft{
  background: linear-gradient(0deg, rgba(6,14,19,0.55) 0%, rgba(6,14,19,0) 35%),
              linear-gradient(180deg, rgba(6,14,19,0.35) 0%, rgba(6,14,19,0) 22%);
}

/* --- reel 1 overlay: logo mark --- */
.hero-mark{
  --mark-o: 1;
  position: absolute; top: 0; right: 0; height: 100%;
  display: flex; align-items: center;
  padding-right: clamp(24px, 7vw, 96px);
  opacity: var(--mark-o);
  transform: translateY(calc((1 - var(--mark-o)) * -22px)) scale(calc(1 - (1 - var(--mark-o)) * 0.03));
  will-change: opacity, transform;
}
.hero-mark__glass{
  background: var(--glass-fill-strong);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(26px) saturate(150%);
  -webkit-backdrop-filter: blur(26px) saturate(150%);
  padding: clamp(38px,4.2vw,60px) clamp(42px,4.6vw,72px);
  text-align: right;
  box-shadow: 0 30px 60px -20px rgba(0,0,0,0.6), 0 1px 0 rgba(255,255,255,0.08) inset;
  max-width: min(92vw, 620px);
}
.hero-mark__logos{ display:flex; align-items:center; justify-content:flex-end; gap: 24px; margin-bottom: 24px; }
.hero-mark__logo{ height: 52px; width: auto; object-fit: contain; }
.hero-mark__logo--dvina{ height: 44px; opacity: .97; }
.hero-mark__logo--nsv{ height: 60px; }
.hero-mark__sep{ width: 1px; height: 36px; background: var(--glass-border-strong); }
.hero-mark__script{
  font-family: var(--font-script);
  font-weight: 400;
  font-size: clamp(58px, 7.4vw, 104px);
  line-height: 1;
  color: var(--c-foam);
  margin: 0 0 14px;
}
.hero-mark__caption{
  margin:0; font-size: 14px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--ink-mid);
}

.scroll-cue{
  position: absolute; left: 50%; bottom: 44px; transform: translateX(-50%);
  display:flex; flex-direction:column; align-items:center; gap: 10px;
  color: var(--ink-mid); transition: opacity .4s;
}
.scroll-cue span{ font-size: 11px; letter-spacing: 0.18em; text-transform: uppercase; font-weight: 700; }
.scroll-cue__line{ width: 1px; height: 34px; background: linear-gradient(180deg, var(--c-foam), transparent); animation: cue-pulse 1.8s ease-in-out infinite; }
@keyframes cue-pulse{ 0%,100%{ opacity:.3; transform: scaleY(.7); transform-origin: top;} 50%{ opacity:1; transform: scaleY(1); transform-origin: top;} }

/* --- reel 2 overlay: hinge stat panel --- */
.hinge-stat{
  --stat-o: 0;
  position: absolute; left: 0; right: 0; bottom: clamp(48px, 9vh, 110px);
  display: flex; justify-content: center;
  padding: 0 var(--gutter);
  opacity: var(--stat-o);
  transform: translateY(calc((1 - var(--stat-o)) * 18px));
  will-change: opacity, transform;
}
.hinge-stat__glass{
  display: grid; grid-auto-flow: column; gap: clamp(20px, 3vw, 56px);
  background: var(--glass-fill-strong);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(26px) saturate(150%);
  -webkit-backdrop-filter: blur(26px) saturate(150%);
  padding: 26px clamp(24px, 3vw, 48px);
  box-shadow: 0 30px 60px -20px rgba(0,0,0,0.6), 0 1px 0 rgba(255,255,255,0.08) inset;
}
.hinge-stat__item{ display:flex; flex-direction:column; align-items:flex-start; gap: 2px; }
.hinge-stat__num{ font-size: clamp(22px,2.4vw,30px); font-weight: 800; color: var(--c-foam); letter-spacing:-0.02em; }
.hinge-stat__unit{ font-size: 12px; font-weight: 700; color: var(--c-accent); margin-top:-4px; }
.hinge-stat__label{ font-size: 11px; color: var(--ink-mid); text-transform: uppercase; letter-spacing: 0.06em; margin-top: 6px; }

/* ==========================================================================
   CONTENT COMPONENTS
   ========================================================================== */

/* --- split media/text rows --- */
.wrap--split{
  display: grid; grid-template-columns: 1fr 1fr; gap: clamp(32px, 6vw, 96px);
  align-items: center;
}
.section--split-rev .split__text{ order: 2; }
.section--split-rev .split__media{ order: 1; }
.split__media img{ border-radius: var(--radius-lg); width: 100%; height: clamp(280px, 34vw, 460px); object-fit: cover; box-shadow: 0 30px 60px -24px rgba(0,0,0,0.55); }
.split__text p{ color: var(--ink-mid); font-size: 15.5px; }

/* --- feature grid (2-up glass cards) --- */
.feature-grid{ display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 40px; }
.feature-grid--three{ grid-template-columns: repeat(3, 1fr); }
.feature-card{ padding: 30px 32px; }
.feature-card--compact{ padding: 26px 26px; }
.feature-card__tag{
  display:inline-block; font-size: 11.5px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--c-accent); margin-bottom: 14px;
}
.feature-card h3{ font-size: 21px; margin-bottom: 10px; color: var(--ink-hi); }
.feature-card p{ color: var(--ink-mid); font-size: 14.5px; margin: 0; }

/* --- stat row (in-numbers) --- */
.stat-row{
  display: grid; grid-template-columns: repeat(6, 1fr); gap: 1px;
  margin-top: 56px;
  background: var(--glass-border);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.stat-row__item{
  background: var(--glass-fill);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  padding: 26px 18px;
  display:flex; flex-direction:column; align-items:flex-start; gap: 4px;
}
.stat-row .icon{ width: 22px; height: 22px; color: var(--c-accent); margin-bottom: 10px; }
.stat-row__num{ font-size: clamp(18px,1.7vw,22px); font-weight: 800; color: var(--ink-hi); letter-spacing: -0.01em; }
.stat-row__unit{ font-size: 12px; font-weight: 700; color: var(--c-accent); }
.stat-row__label{ font-size: 12px; color: var(--ink-mid); margin-top: 8px; }
.stat-row__footnote{ margin-top: 16px; font-size: 13px; color: var(--ink-lo); text-align: center; }

/* --- unsinkability diagram --- */
.unsink-grid{ display:grid; grid-template-columns: 1.1fr 1fr; gap: clamp(28px,5vw,64px); align-items:center; margin-top: 44px; }
.unsink-diagram{ background: rgba(255,255,255,0.04); border: 1px solid var(--glass-border); border-radius: var(--radius-lg); padding: 20px; }
.unsink-diagram img{ width:100%; height:auto; border-radius: var(--radius-md); }
.unsink-list{ display:flex; flex-direction:column; gap: 18px; counter-reset: unsink; }
.unsink-list li{ display:flex; gap: 16px; align-items:flex-start; color: var(--ink-mid); font-size: 14.5px; line-height: 1.55; }
.unsink-list__n{
  flex: none; width: 28px; height: 28px; border-radius: 50%;
  border: 1px solid var(--c-accent); color: var(--c-foam);
  display:flex; align-items:center; justify-content:center;
  font-size: 12px; font-weight: 800;
}

/* --- config cards --- */
.config-grid{ display:grid; grid-template-columns: repeat(3,1fr); gap: 22px; margin-top: 48px; }
.config-card{
  border-radius: var(--radius-lg); overflow:hidden;
  background: var(--glass-fill); border: 1px solid var(--glass-border);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  display:flex; flex-direction:column;
  transition: transform .4s var(--ease-out), border-color .4s;
}
.config-card:hover{ transform: translateY(-6px); border-color: var(--glass-border-strong); }
.config-card__media{ aspect-ratio: 4/3; overflow:hidden; }
.config-card__media img{ width:100%; height:100%; object-fit:cover; transition: transform .6s var(--ease-out); }
.config-card:hover .config-card__media img{ transform: scale(1.06); }
.config-card__body{ padding: 26px 26px 28px; display:flex; flex-direction:column; gap: 10px; }
.config-card__code{ font-size: 11.5px; font-weight: 800; letter-spacing: 0.1em; text-transform: uppercase; color: var(--c-accent); }
.config-card__body h3{ font-size: 21px; color: var(--ink-hi); }
.config-card__body p{ font-size: 14px; color: var(--ink-mid); margin: 0 0 6px; }
.config-card__specs{ display:flex; flex-direction:column; gap: 6px; margin: 8px 0 0; padding-top: 14px; border-top: 1px solid var(--glass-border); }
.config-card__specs div{ display:flex; justify-content:space-between; gap: 10px; font-size: 12.5px; }
.config-card__specs dt{ color: var(--ink-lo); font-weight: 600; }
.config-card__specs dd{ margin:0; color: var(--ink-hi); font-weight: 700; text-align: right; }

.options-note{
  margin-top: 28px; padding: 26px 30px; display:flex; gap: 22px; align-items:flex-start;
}
.options-note__icon{ flex:none; width: 44px; height:44px; color: var(--c-accent); }
.options-note h4{ font-size: 16px; color: var(--ink-hi); margin-bottom: 8px; }
.options-note p{ font-size: 14px; color: var(--ink-mid); margin: 0; }

/* --- film strip gallery --- */
.film-strip{ display:grid; grid-template-columns: repeat(4,1fr); gap: 14px; }
.film-strip--tactical{ grid-template-columns: repeat(2,1fr); margin-top: 40px; }
.film-strip__item{ border-radius: var(--radius-md); overflow:hidden; aspect-ratio: 4/5; }
.film-strip--tactical .film-strip__item{ aspect-ratio: 16/10; }
.film-strip__item img{ width:100%; height:100%; object-fit:cover; transition: transform .6s var(--ease-out); }
.film-strip__item:hover img{ transform: scale(1.05); }

/* ==========================================================================
   BEC — synergy + platform cards
   ========================================================================== */
.synergy-grid{ display:grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 44px; }
.synergy-card{ padding: 32px; }
.synergy-card__index{ display:block; font-size: 12px; font-weight: 800; color: var(--c-accent); letter-spacing: 0.1em; margin-bottom: 14px; }
.synergy-card h3{ font-size: 19px; color: var(--ink-hi); margin-bottom: 12px; line-height:1.3; }
.synergy-card p{ font-size: 14.5px; color: var(--ink-mid); margin:0; }

.bec-card{
  border-radius: var(--radius-xl);
  background: var(--glass-fill);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  padding: clamp(28px,4vw,48px);
}
.bec-card--flagship{ border-color: var(--glass-border-strong); background: var(--glass-fill-strong); }
.bec-card__head{ display:flex; justify-content:space-between; gap: 40px; flex-wrap:wrap; align-items:flex-end; margin-bottom: 30px; }
.bec-card__eyebrow{ display:block; font-size: 12px; font-weight: 800; letter-spacing: 0.1em; text-transform:uppercase; color: var(--c-accent); margin-bottom: 8px; }
.bec-card__title{ font-size: clamp(30px,3.4vw,42px); color: var(--ink-hi); letter-spacing: -0.02em; }
.bec-card__desc{ max-width: 40ch; font-size: 14.5px; color: var(--ink-mid); margin: 0; }

.bec-card__media{ display:grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 30px; }
.bec-card__media figure{ margin:0; position:relative; border-radius: var(--radius-md); overflow:hidden; aspect-ratio: 16/11; }
.bec-card__media img{ width:100%; height:100%; object-fit:cover; transition: transform .6s var(--ease-out); }
.bec-card__media figure:hover img{ transform: scale(1.05); }
.bec-card__media figcaption{
  position:absolute; left: 14px; bottom: 14px;
  font-size: 11.5px; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--c-foam);
  background: rgba(6,20,27,0.55); backdrop-filter: blur(10px);
  border: 1px solid var(--glass-border);
  padding: 6px 12px; border-radius: 999px;
}

.bec-card__specs{ display:grid; grid-template-columns: repeat(4,1fr); gap: 18px 24px; padding-top: 24px; border-top: 1px solid var(--glass-border); }
.bec-card__specs div{ display:flex; flex-direction:column; gap: 4px; }
.bec-card__specs dt{ font-size: 11.5px; color: var(--ink-lo); text-transform: uppercase; letter-spacing: 0.04em; }
.bec-card__specs dd{ margin:0; font-size: 14.5px; font-weight: 700; color: var(--ink-hi); }

/* --- scenario list (numbered — genuine sequence of use-cases) --- */
.scenario-list{ display:flex; flex-direction:column; margin-top: 40px; }
.scenario-item{
  display:flex; gap: 24px; padding: 26px 0; border-top: 1px solid var(--glass-border);
}
.scenario-item:last-child{ border-bottom: 1px solid var(--glass-border); }
.scenario-item__n{ flex: none; font-size: 13px; font-weight: 800; color: var(--c-accent); padding-top: 3px; width: 28px; }
.scenario-item h4{ font-size: 17px; color: var(--ink-hi); margin-bottom: 8px; }
.scenario-item p{ font-size: 14.5px; color: var(--ink-mid); margin:0; max-width: 68ch; }

.tactical-grid{ display:grid; grid-template-columns: repeat(3,1fr); gap: 20px; margin-top: 40px; }
.tactical-card{ padding: 28px; }
.tactical-card h4{ font-size: 16.5px; color: var(--ink-hi); margin-bottom: 10px; }
.tactical-card p{ font-size: 14px; color: var(--ink-mid); margin:0; }

/* ==========================================================================
   ABOUT NSV — pills, produce grid, app cards, signature, process, closing
   ========================================================================== */
.pill-grid{ display:flex; flex-wrap:wrap; gap: 12px; margin-top: 36px; }
.pill{
  padding: 11px 20px; border-radius: 999px;
  background: var(--glass-fill); border: 1px solid var(--glass-border);
  font-size: 13.5px; font-weight: 700; color: var(--ink-hi);
  backdrop-filter: blur(14px);
}

.produce-grid{
  display:grid; grid-template-columns: repeat(3,1fr); gap: 1px;
  margin-top: 40px; background: var(--glass-border); border: 1px solid var(--glass-border); border-radius: var(--radius-lg); overflow:hidden;
}
.produce-grid span{
  background: var(--glass-fill); padding: 20px 24px; font-size: 14.5px; font-weight: 700; color: var(--ink-hi);
}

.app-grid{ display:grid; grid-template-columns: repeat(4,1fr); gap: 18px; }
.app-grid--three{ grid-template-columns: repeat(3,1fr); }
.app-card{ padding: 26px; }
.app-card__tag{ display:block; font-size: 14.5px; font-weight: 800; color: var(--ink-hi); margin-bottom: 12px; }
.app-card p{ font-size: 13.5px; color: var(--ink-mid); margin:0; line-height:1.55; }

.signature-section{
  display:grid; grid-template-columns: 0.9fr 1.1fr; height: 82vh; min-height: 560px; max-height: 900px;
  border-top: 1px solid var(--glass-border); border-bottom: 1px solid var(--glass-border);
}
.signature-section__media{ position:relative; overflow:hidden; background: var(--c-hull); }
.signature-section__media img{ width:100%; height:100%; object-fit: cover; object-position: center 20%; }
.signature-section__media::after{
  content:""; position:absolute; inset:0;
  background: linear-gradient(90deg, transparent 70%, var(--c-abyss) 100%);
}
.signature-section__text{
  display:flex; flex-direction:column; justify-content:center;
  padding: clamp(48px,6vw,96px);
  background:
    radial-gradient(ellipse 80% 60% at 100% 50%, rgba(37,55,69,0.5), transparent 70%),
    var(--c-abyss);
}
.signature-section__text p{ color: var(--ink-mid); font-size: 15px; }

.process-list{ display:flex; flex-direction:column; margin-top: 44px; counter-reset: process; }
.process-list li{ display:flex; gap: 26px; padding: 24px 0; border-top: 1px solid var(--glass-border); align-items:flex-start; }
.process-list li:last-child{ border-bottom: 1px solid var(--glass-border); }
.process-list__n{ flex:none; font-size: 26px; font-weight: 800; color: var(--c-accent); opacity:.55; width: 56px; letter-spacing:-0.02em; }
.process-list h4{ font-size: 17px; color: var(--ink-hi); margin-bottom: 4px; }
.process-list p{ font-size: 14px; color: var(--ink-mid); margin:0; }

.closing-banner{
  position: relative; min-height: 74vh; display:flex; align-items:flex-end; overflow:hidden;
}
.closing-banner__img{ position:absolute; inset:0; width:100%; height:100%; object-fit:cover; }
.closing-banner__scrim{
  position:absolute; inset:0;
  background: linear-gradient(0deg, rgba(6,14,19,0.92) 10%, rgba(6,14,19,0.35) 55%, rgba(6,14,19,0.55) 100%);
}
.closing-banner__content{ position:relative; z-index:2; width:100%; padding: 64px var(--gutter) 72px; max-width: var(--content-max); margin: 0 auto; display:flex; justify-content:space-between; gap: 40px; flex-wrap:wrap; align-items:flex-end; }
.closing-banner__tagline{ font-size: clamp(22px,2.6vw,32px); font-weight: 800; color: var(--c-foam); letter-spacing: -0.02em; margin:0; text-align:right; }

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer{
  background: var(--c-hull);
  border-top: 1px solid var(--glass-border);
  padding: clamp(56px,7vw,88px) 0 28px;
}
.site-footer__top{
  display:grid; grid-template-columns: 1.4fr 0.8fr 0.8fr 1.1fr; gap: clamp(24px,4vw,40px);
  padding-bottom: 44px; border-bottom: 1px solid var(--glass-border);
}
.site-footer__mark{ width: 40px; margin-bottom: 14px; }
.site-footer__script{ font-family: var(--font-script); font-size: 34px; color: var(--c-foam); margin: 0 0 14px; }
.site-footer__addr{ font-size: 13.5px; color: var(--ink-mid); line-height: 1.6; }
.site-footer__col{ display:flex; flex-direction:column; gap: 12px; }
.site-footer__col h5{ font-size: 12px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-lo); margin-bottom: 4px; }
.site-footer__col a{ font-size: 14.5px; color: var(--ink-mid); font-weight: 600; transition: color .2s; }
.site-footer__col a:hover{ color: var(--c-foam); }
.site-footer__cta-col{ gap: 14px; }
.site-footer__cta-col .btn{ align-self: flex-start; margin-top: 4px; }
.site-footer__bottom{
  display:flex; justify-content:space-between; padding-top: 22px;
  font-size: 12.5px; color: var(--ink-lo);
}

/* ==========================================================================
   SCROLL-REVEAL utility (IntersectionObserver driven)
   ========================================================================== */
.reveal-img{ opacity: 0; transform: translateY(28px); transition: opacity .9s var(--ease-out), transform .9s var(--ease-out); }
.reveal-img.is-in{ opacity: 1; transform: translateY(0); }

[data-reveal]{ opacity: 0; transform: translateY(22px); transition: opacity .8s var(--ease-out), transform .8s var(--ease-out); }
[data-reveal].is-in{ opacity: 1; transform: translateY(0); }

.reveal-el{ opacity: 0; transform: translateY(20px); transition: opacity .7s var(--ease-out), transform .7s var(--ease-out); }
.reveal-el.is-in{ opacity: 1; transform: translateY(0); }

/* ==========================================================================
   RESPONSIVE — tablet
   ========================================================================== */
@media (max-width: 1080px){
  .feature-grid--three{ grid-template-columns: repeat(2,1fr); }
  .app-grid{ grid-template-columns: repeat(2,1fr); }
  .app-grid--three{ grid-template-columns: 1fr; }
  .produce-grid{ grid-template-columns: repeat(2,1fr); }
  .bec-card__specs{ grid-template-columns: repeat(2,1fr); }
  .tactical-grid{ grid-template-columns: repeat(2,1fr); }
  .stat-row{ grid-template-columns: repeat(3,1fr); }
  .stat-row__item:nth-child(3){ border-right: none; }
  .config-grid{ grid-template-columns: repeat(2,1fr); }
  .config-grid article:last-child{ grid-column: 1 / -1; }
  .config-grid article:last-child .config-card__media{ aspect-ratio: 21/9; }
  .site-nav__links{ gap: 20px; }
}

/* ==========================================================================
   RESPONSIVE — mobile (nav becomes burger + sheet)
   ========================================================================== */
@media (max-width: 860px){
  :root{ --gutter: 22px; }

  /* nav */
  .site-nav__links, .site-nav__cta{ display: none; }
  .site-nav__burger{ display:flex; }
  .site-nav__brandtext{ font-size: 14px; }

  /* reels */
  .reel{ height: 210vh; height: calc(var(--vh, 1vh) * 210); }
  .reel--hero{ height: 280vh; height: calc(var(--vh, 1vh) * 280); }
  .reel--usv{ height: 150vh; height: calc(var(--vh, 1vh) * 150); }

  .hero-mark{
    right: 0; left: 0; justify-content: center; align-items: flex-end;
    padding: 0 18px 96px;
  }
  .hero-mark__glass{ text-align:center; max-width: 100%; padding: 32px 26px; }
  .hero-mark__logos{ justify-content:center; }
  .hero-mark__script{ font-size: clamp(48px,15vw,66px); }

  .hinge-stat{ bottom: 34px; }
  .hinge-stat__glass{ grid-auto-flow: row; grid-template-columns: repeat(2,1fr); gap: 20px 28px; width: 100%; }
  .hinge-stat__item{ align-items: flex-start; }

  .unsink-grid{ grid-template-columns: 1fr; gap: 32px; }

  /* split rows stack */
  .wrap--split{ grid-template-columns: 1fr; gap: 28px; }
  .section--split-rev .split__text{ order: 1; }
  .section--split-rev .split__media{ order: 2; }
  .split__media img{ height: 56vw; }

  /* grids collapse */
  .feature-grid, .feature-grid--three{ grid-template-columns: 1fr; }
  .config-grid{ grid-template-columns: 1fr; }
  .config-grid article:last-child{ grid-column: auto; }
  .config-grid article:last-child .config-card__media{ aspect-ratio: 4/3; }
  .app-grid{ grid-template-columns: 1fr; }
  .produce-grid{ grid-template-columns: 1fr 1fr; }
  .synergy-grid{ grid-template-columns: 1fr; }
  .tactical-grid{ grid-template-columns: 1fr; }
  .stat-row{ grid-template-columns: repeat(2,1fr); }
  .film-strip{ grid-template-columns: repeat(2,1fr); }
  .film-strip--tactical{ grid-template-columns: 1fr; }

  .bec-card__media{ grid-template-columns: 1fr 1fr; gap: 10px; }
  .bec-card__specs{ grid-template-columns: 1fr 1fr; }
  .bec-card__head{ flex-direction: column; align-items: flex-start; gap: 14px; }

  .signature-section{ grid-template-columns: 1fr; height: auto; min-height: auto; max-height: none; }
  .signature-section__media{ height: 62vw; }
  .signature-section__media::after{ background: linear-gradient(0deg, var(--c-abyss) 0%, transparent 22%); }
  .signature-section__text{ padding: 44px 24px 56px; }

  .site-footer__top{ grid-template-columns: 1fr 1fr; row-gap: 36px; }
  .site-footer__brand{ grid-column: 1 / -1; }

  .closing-banner__content{ flex-direction: column; align-items: flex-start; gap: 24px; }
  .closing-banner__tagline{ text-align: left; }
}

@media (max-width: 560px){
  .h2{ font-size: clamp(26px, 8vw, 34px); }
  .stat-row{ grid-template-columns: 1fr 1fr; }
  .produce-grid{ grid-template-columns: 1fr; }
  .film-strip{ grid-template-columns: 1fr 1fr; }
  .bec-card{ padding: 24px 20px; }
  .bec-card__media{ grid-template-columns: 1fr; }
  .bec-card__specs{ grid-template-columns: 1fr 1fr; }
  .hero-mark__logo--nsv{ height: 46px; }
  .hero-mark__logo--dvina{ height: 34px; }
  .hero-mark__script{ font-size: 48px; }
  .site-nav__inner{ padding: 14px 18px; }
  .site-footer__top{ grid-template-columns: 1fr; }
}

/* Landscape-short viewports (many mobile browsers mid-scroll) */
@media (max-height: 480px) and (orientation: landscape){
  .reel, .reel--hero{ height: 220vh; }
  .reel--usv{ height: 130vh; }
}