:root {
  --bg: #050505;
  --ink: #111827;
  --muted: #5c6675;
  --line: #dedede;
  --soft: #0f1012;
  --graphite: #050505;
  --graphite-2: #141414;
  --cyan: #ff7a18;
  --cyan-deep: #e95a0c;
  --orange: #ff6a00;
  --orange-deep: #d94e00;
  --amber: #ffb000;
  --paper: #ffffff;
  --dark-line: rgba(255,255,255,.12);
  --shadow: 0 22px 60px rgba(0, 0, 0, .22);
  --orange-glow: 0 18px 48px rgba(255, 106, 0, .28);
  --radius: 8px;
  font-family: Inter, "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--bg); }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
p { color: var(--muted); line-height: 1.65; margin: 0; }

.site-header {
  position: relative;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px clamp(18px, 4vw, 64px);
  background:
    linear-gradient(180deg, rgba(0,0,0,.96), rgba(10,10,10,.94));
  border-bottom: 1px solid rgba(255,106,0,.72);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 0 0 1px rgba(255,106,0,.22), 0 12px 32px rgba(0,0,0,.26);
  font-weight: 800;
}
.brand img { width: 166px; height: auto; }
.main-nav { display: flex; align-items: center; gap: 22px; color: rgba(255,255,255,.84); font-size: 13px; font-weight: 800; text-transform: uppercase; }
.main-nav a, .footer-links a { position: relative; transition: color .2s ease; }
.main-nav a::after, .footer-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: -6px;
  height: 2px;
  background: var(--orange);
  transition: right .24s ease;
}
.main-nav a:hover, .footer-links a:hover { color: #fff; }
.main-nav a:hover::after, .footer-links a:hover::after { right: 0; }
.header-actions { display: flex; align-items: center; gap: 10px; }
.language-switch {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 4px;
  border: 1px solid rgba(255,106,0,.42);
  border-radius: var(--radius);
  background: rgba(255,255,255,.06);
}
.language-switch a {
  min-width: 42px;
  padding: 8px 10px;
  border-radius: 6px;
  color: rgba(255,255,255,.72);
  font-size: 12px;
  font-weight: 900;
  line-height: 1;
  text-align: center;
  transition: color .2s ease, background .2s ease;
}
.language-switch a:hover,
.language-switch a[aria-current="true"] {
  color: #fff;
  background: var(--orange);
}
.menu-toggle { display: none; }

.button, button.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font: 800 14px/1 Inter, "Segoe UI", Arial, sans-serif;
  cursor: pointer;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease, border-color .2s ease, color .2s ease;
}
.button:hover { transform: translateY(-2px); }
.button.primary { background: linear-gradient(135deg, var(--orange), var(--orange-deep)); color: #fff; box-shadow: var(--orange-glow); }
.button.primary:hover { box-shadow: 0 20px 58px rgba(255, 106, 0, .38); }
.button.secondary { background: #fff; color: var(--graphite); border-color: rgba(255,106,0,.45); }
.button.secondary:hover { border-color: var(--orange); box-shadow: 0 14px 34px rgba(255,106,0,.16); }
.button.accent { background: var(--orange); color: #fff; }

.hero {
  position: relative;
  isolation: isolate;
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(420px, .85fr);
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
  min-height: calc(100vh - 74px);
  padding: clamp(54px, 8vw, 96px) clamp(18px, 5vw, 76px) 42px;
  background:
    radial-gradient(circle at 78% 42%, rgba(255,106,0,.34), transparent 28%),
    linear-gradient(90deg, rgba(0,0,0,.98) 0%, rgba(0,0,0,.92) 42%, rgba(0,0,0,.72) 100%),
    var(--graphite);
  color: #fff;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(255,106,0,.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,106,0,.06) 1px, transparent 1px);
  background-size: 54px 54px;
  mask-image: linear-gradient(90deg, rgba(0,0,0,.5), transparent 62%);
}
.hero::after {
  content: "";
  position: absolute;
  left: clamp(18px, 5vw, 76px);
  right: clamp(18px, 5vw, 76px);
  top: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--orange), transparent 72%);
}
.hero h1 {
  margin: 0;
  max-width: 760px;
  font-size: clamp(42px, 4.8vw, 62px);
  line-height: .96;
  letter-spacing: 0;
  color: #fff;
  text-transform: uppercase;
  overflow-wrap: normal;
  word-break: normal;
}
.hero .lead { margin-top: 24px; max-width: 660px; color: rgba(255,255,255,.84); font-size: 19px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.hero .button.secondary { background: transparent; color: #fff; border-color: var(--orange); }
.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 38px 0 0;
  max-width: 650px;
  background: rgba(255,106,0,.35);
  border: 1px solid rgba(255,106,0,.42);
}
.hero-facts div { background: rgba(10,10,10,.78); padding: 18px; }
.hero-facts dt { color: var(--orange); font-size: 26px; font-weight: 900; }
.hero-facts dd { margin: 4px 0 0; color: rgba(255,255,255,.72); font-size: 13px; line-height: 1.4; }
.hero-visual { position: relative; }
.hero-visual::before {
  content: "";
  position: absolute;
  inset: 9% -6% -7% 10%;
  z-index: -1;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,106,0,.36), transparent 66%);
  filter: blur(8px);
}
.hero-visual img { border: 1px solid rgba(255,106,0,.32); border-radius: var(--radius); box-shadow: 0 30px 80px rgba(0,0,0,.46); background: var(--soft); }
.visual-note {
  position: absolute;
  right: 24px;
  bottom: 24px;
  display: grid;
  gap: 4px;
  width: min(310px, 72%);
  padding: 18px;
  border-radius: var(--radius);
  border: 1px solid rgba(255,106,0,.36);
  background: rgba(5,5,5,.86);
  color: #fff;
  box-shadow: 0 18px 42px rgba(0,0,0,.28);
}
.visual-note span { color: #b9c7d3; font-size: 14px; line-height: 1.4; }

.section, .legal-hero, .legal-layout { padding: clamp(64px, 8vw, 110px) clamp(18px, 5vw, 76px); background: #fff; }
.section.dark {
  position: relative;
  background:
    radial-gradient(circle at 72% 10%, rgba(255,106,0,.18), transparent 34%),
    var(--graphite);
  color: #fff;
}
.section.soft {
  background:
    linear-gradient(135deg, rgba(255,106,0,.10), transparent 34%),
    #101010;
  color: #fff;
}
.section.soft > .section-head p, .section.soft .process-grid > .section-head p { color: rgba(255,255,255,.72); }
.section-head { max-width: 850px; margin-bottom: 34px; }
.section-head h2, .legal-hero h1 {
  margin: 0 0 14px;
  font-size: clamp(32px, 4vw, 56px);
  line-height: 1.05;
  letter-spacing: 0;
}
.section-head h2::after, .legal-hero h1::after {
  content: "";
  display: block;
  width: 82px;
  height: 3px;
  margin-top: 18px;
  background: linear-gradient(90deg, var(--orange), transparent);
}
.dark p, .dark .muted { color: #b9c7d3; }

.product-showcase {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 26px;
  align-items: stretch;
}
.product-panel, .solution-panel, .doc-panel, .contact-panel, .legal-article, .legal-aside {
  border: 1px solid rgba(17,24,39,.12);
  border-radius: var(--radius);
  background: #fff;
  transition: transform .22s ease, border-color .22s ease, box-shadow .22s ease;
}
.product-panel:hover, .solution-panel:hover, .doc-panel:hover {
  transform: translateY(-4px);
  border-color: rgba(255,106,0,.48);
  box-shadow: 0 22px 54px rgba(0,0,0,.16), 0 0 0 1px rgba(255,106,0,.08);
}
.product-panel { overflow: hidden; }
.product-panel img { width: 100%; aspect-ratio: 16 / 10; object-fit: cover; background: #0d0d0d; }
.product-panel.large { display: grid; grid-template-columns: .9fr 1fr; align-items: center; }
.product-copy { padding: 28px; }
.product-copy h3, .solution-panel h3, .doc-panel h3 { margin: 0 0 10px; font-size: 26px; }
.product-copy ul, .solution-panel ul, .legal-article ul, .legal-article ol { color: var(--muted); line-height: 1.8; padding-left: 20px; }
.product-links { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }
.product-stack { display: grid; gap: 26px; }

.applications {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: rgba(255,255,255,.16);
  border: 1px solid rgba(255,255,255,.16);
}
.applications article { position: relative; background: var(--graphite-2); padding: 26px; min-height: 220px; transition: background .22s ease, transform .22s ease; }
.applications article::before {
  content: "";
  position: absolute;
  left: 26px;
  top: 0;
  width: 54px;
  height: 3px;
  background: var(--orange);
}
.applications article:hover { background: #1b1b1b; transform: translateY(-3px); }
.applications h3 { margin: 0 0 12px; font-size: 21px; }
.applications p { color: #b9c7d3; }

.about-grid {
  display: grid;
  grid-template-columns: minmax(0, .95fr) minmax(320px, .75fr);
  gap: clamp(22px, 4vw, 44px);
  align-items: start;
}
.about-grid .section-head { margin-bottom: 0; }
.about-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}
.about-facts span {
  border: 1px solid rgba(255,106,0,.34);
  background: rgba(255,106,0,.08);
  color: #101820;
  border-radius: 999px;
  padding: 10px 14px;
  font-size: 13px;
  font-weight: 900;
  text-transform: uppercase;
}
.certificate-card {
  background: linear-gradient(145deg, #101010, #1f1209);
  border: 1px solid rgba(255,106,0,.36);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
  color: #fff;
}
.certificate-card small { color: var(--orange); font-weight: 900; letter-spacing: .08em; }
.certificate-card h3 { margin: 10px 0; font-size: 24px; color: #fff; }
.certificate-card p { color: rgba(255,255,255,.76); }
.certificate-preview {
  display: block;
  overflow: hidden;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,.14);
  background: #fff;
  margin-bottom: 18px;
}
.certificate-preview img,
.certificate-doc-card img {
  display: block;
  width: 100%;
  height: auto;
}
.certificate-preview img {
  max-height: 360px;
  object-fit: cover;
  object-position: top center;
  transition: transform .45s ease;
}
.certificate-preview:hover img { transform: scale(1.025); }
.certificate-doc-card {
  display: flex;
  flex-direction: column;
}
.certificate-doc-card img {
  max-height: 260px;
  object-fit: cover;
  object-position: top center;
  border-radius: 8px;
  border: 1px solid rgba(255,106,0,.22);
  margin-bottom: 16px;
}

.process-grid {
  display: grid;
  grid-template-columns: .8fr 1.2fr;
  gap: 28px;
  align-items: start;
}
.process-rail { display: grid; gap: 14px; counter-reset: step; }
.process-rail article {
  position: relative;
  padding: 22px 22px 22px 68px;
  border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius);
  background: rgba(255,255,255,.06);
  color: #fff;
  transition: border-color .22s ease, transform .22s ease, background .22s ease;
}
.process-rail article:hover {
  transform: translateX(4px);
  border-color: rgba(255,106,0,.55);
  background: rgba(255,255,255,.09);
}
.process-rail article::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 20px;
  top: 20px;
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--orange);
  color: #fff;
  font-weight: 900;
}
.doc-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.doc-panel { padding: 24px; }
.doc-panel small { display: block; color: var(--orange); font-weight: 900; margin-bottom: 12px; }

.contacts {
  display: grid;
  grid-template-columns: .85fr 1.15fr;
  gap: 28px;
  align-items: start;
}
.contact-panel { padding: 28px; }
.section.soft .contact-panel {
  border-color: rgba(255,255,255,.14);
  background: rgba(255,255,255,.06);
  color: #fff;
}
.section.soft .contact-panel p { color: rgba(255,255,255,.72); }
.contact-list { display: grid; gap: 14px; margin-top: 24px; color: var(--muted); }
.section.soft .contact-list { color: rgba(255,255,255,.84); }
.section.soft .contact-list a { color: #fff; }
.lead-form { display: grid; gap: 16px; }
.form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
label { display: grid; gap: 7px; color: #334155; font-size: 14px; font-weight: 800; }
.section.soft label { color: rgba(255,255,255,.86); }
input, select, textarea {
  width: 100%;
  min-height: 46px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 11px 12px;
  font: 500 15px/1.4 Inter, "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  background: #fff;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--orange);
  box-shadow: 0 0 0 4px rgba(255,106,0,.14);
}
textarea { min-height: 126px; resize: vertical; }
.consent-field { display: flex; gap: 10px; align-items: flex-start; font-weight: 500; line-height: 1.45; }
.consent-field input { width: 18px; min-height: 18px; margin-top: 2px; flex: 0 0 auto; }
.consent-field a { color: var(--orange-deep); font-weight: 800; }
.field-hint, .form-status { color: var(--muted); font-size: 13px; }
.form-status.success { color: #047857; }
.form-status.error { color: #b91c1c; }

.page-hero {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(320px, .7fr);
  gap: 38px;
  align-items: center;
  padding: clamp(54px, 8vw, 96px) clamp(18px, 5vw, 76px);
  background:
    radial-gradient(circle at 78% 20%, rgba(255,106,0,.22), transparent 32%),
    var(--graphite);
  color: #fff;
}
.page-hero p { color: rgba(255,255,255,.76); }
.page-hero h1 { margin: 0 0 18px; font-size: clamp(38px, 5vw, 66px); line-height: 1; }
.page-hero h1 { overflow-wrap: break-word; }
.breadcrumb { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 20px; color: var(--muted); font-size: 14px; }
.page-hero .breadcrumb { color: rgba(255,255,255,.62); }
.breadcrumb a { color: var(--orange); font-weight: 800; }
.spec-list { display: grid; gap: 12px; margin-top: 22px; }
.spec-list div { display: flex; justify-content: space-between; gap: 18px; padding: 14px 0; border-bottom: 1px solid var(--line); }
.spec-list dt { font-weight: 900; }
.spec-list dd { margin: 0; color: var(--muted); text-align: right; }
.page-hero .spec-list div { border-bottom-color: rgba(255,255,255,.16); }
.page-hero .spec-list dd { color: rgba(255,255,255,.68); }

.legal-hero { background: var(--graphite); color: #fff; padding-bottom: 48px; }
.legal-hero p { color: rgba(255,255,255,.72); }
.legal-layout { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 26px; align-items: start; padding-top: 36px; }
.legal-article { padding: clamp(24px, 4vw, 44px); }
.legal-article section + section { margin-top: 34px; padding-top: 30px; border-top: 1px solid var(--line); }
.legal-article h2 { margin: 0 0 12px; font-size: 28px; }
.legal-aside { position: sticky; top: 96px; display: grid; gap: 12px; padding: 22px; }
.legal-aside h2 { margin: 0 0 8px; }
.legal-aside a { color: var(--orange-deep); font-weight: 800; }

.converter-hero {
  background:
    linear-gradient(135deg, rgba(0, 0, 0, .96), rgba(32, 16, 6, .9)),
    radial-gradient(circle at 84% 20%, rgba(255, 106, 0, .35), transparent 34%),
    var(--graphite);
  color: #fff;
}
.converter-hero p,
.converter-hero .breadcrumb { color: #c6d4df; }
.converter-hero .breadcrumb a { color: var(--orange); }
.converter-summary {
  display: grid;
  gap: 10px;
  padding: 26px;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: var(--radius);
  background: rgba(255,255,255,.08);
}
.converter-summary strong { color: var(--orange); font-size: 18px; }
.converter-section {
  display: grid;
  grid-template-columns: minmax(0, .95fr) minmax(320px, .75fr);
  gap: 22px;
  align-items: start;
}
.converter-panel {
  border: 1px solid rgba(17,24,39,.12);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}
.converter-form {
  display: grid;
  gap: 16px;
  padding: clamp(22px, 3vw, 34px);
}
.section-head.compact { margin-bottom: 4px; }
.section-head.compact h2 { font-size: clamp(26px, 3vw, 34px); }
.converter-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.converter-note {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.55;
}
.result-panel {
  position: sticky;
  top: 98px;
  padding: clamp(22px, 3vw, 34px);
}
.converter-results {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 20px 0;
}
.converter-results div {
  min-height: 112px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff7ed;
}
.converter-results dt {
  margin-bottom: 12px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 900;
  text-transform: uppercase;
}
.converter-results dd {
  margin: 0;
  color: var(--graphite);
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 900;
  line-height: 1;
  overflow-wrap: anywhere;
}
.gas-meta,
.calc-meta {
  display: grid;
  gap: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}
.gas-meta strong { color: var(--ink); font-size: 17px; }

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 28px clamp(18px, 5vw, 76px);
  border-top: 1px solid rgba(255,106,0,.42);
  background: var(--graphite);
  color: #fff;
}
.footer-links { display: flex; flex-wrap: wrap; gap: 18px; color: #b9c7d3; font-size: 14px; }

@media (prefers-reduced-motion: no-preference) {
  .hero-visual::before { animation: mcq-glow 6s ease-in-out infinite; }
  @keyframes mcq-glow {
    0%, 100% { opacity: .58; transform: scale(.98); }
    50% { opacity: .92; transform: scale(1.03); }
  }
}

@media (max-width: 980px) {
  .site-header { align-items: flex-start; flex-wrap: wrap; }
  .main-nav { order: 3; width: 100%; flex-wrap: wrap; gap: 14px 20px; padding-bottom: 3px; }
  .hero, .product-showcase, .product-panel.large, .about-grid, .process-grid, .contacts, .page-hero, .legal-layout, .converter-section { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .applications, .doc-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .legal-aside, .result-panel { position: static; }
}

@media (max-width: 640px) {
  .site-header {
    display: grid;
    grid-template-columns: auto auto;
    align-items: center;
    gap: 14px;
    padding: 12px 18px 0;
  }
  .brand { justify-self: start; padding: 6px 10px; }
  .brand img { width: 146px; }
  .menu-toggle {
    position: relative;
    display: inline-grid;
    place-items: center;
    justify-self: end;
    width: 48px;
    height: 44px;
    border: 1px solid rgba(255,106,0,.72);
    border-radius: var(--radius);
    background: rgba(255,106,0,.12);
    box-shadow: 0 12px 32px rgba(255,106,0,.16);
    cursor: pointer;
  }
  .menu-toggle span,
  .menu-toggle::before,
  .menu-toggle::after {
    content: "";
    position: absolute;
    left: 50%;
    top: 50%;
    display: block;
    width: 22px;
    height: 2px;
    border-radius: 2px;
    background: #fff;
    transition: transform .22s ease, opacity .22s ease;
  }
  .menu-toggle span { transform: translate(-50%, -50%); }
  .menu-toggle::before { transform: translate(-50%, calc(-50% - 7px)); }
  .menu-toggle::after { transform: translate(-50%, calc(-50% + 7px)); }
  .site-header.is-menu-open .menu-toggle span { opacity: 0; }
  .site-header.is-menu-open .menu-toggle::before { transform: translate(-50%, -50%) rotate(45deg); }
  .site-header.is-menu-open .menu-toggle::after { transform: translate(-50%, -50%) rotate(-45deg); }
  .header-actions {
    display: flex;
    grid-column: 1 / -1;
    order: 2;
    width: 100%;
  }
  .header-actions .button { display: none; }
  .main-nav {
    display: none;
    order: 3;
    grid-column: 1 / -1;
    width: 100%;
    grid-template-columns: 1fr;
    gap: 0;
    padding: 8px 0 12px;
    border-top: 1px solid rgba(255,106,0,.28);
  }
  .site-header.is-menu-open .main-nav { display: grid; }
  .main-nav a {
    padding: 12px 4px;
    border-bottom: 1px solid rgba(255,255,255,.08);
  }
  .language-switch {
    grid-column: 1 / -1;
    justify-self: stretch;
    width: 100%;
    margin-bottom: 12px;
  }
  .language-switch a { flex: 1; }
  .main-nav a::after { display: none; }
  .hero h1 { font-size: clamp(30px, 8.7vw, 34px); line-height: 1.04; }
  .hero .lead { font-size: 17px; }
  .hero-facts, .applications, .doc-grid, .form-grid, .converter-results { grid-template-columns: 1fr; }
  .visual-note { position: static; width: auto; margin-top: 12px; }
  .site-footer { flex-direction: column; }
}