/* ==========================================================
   ДСК — landing styles
   Palette: charcoal steel + brick rust accent
   Display: Oswald / Body: Inter / Mono: JetBrains Mono
   ========================================================== */

:root{
  --bg:            #101214;
  --bg-panel:      #17191c;
  --bg-panel-2:    #1c1f22;
  --line:          #2a2e32;
  --line-soft:     #23262a;
  --steel:         #838d96;
  --steel-dim:     #5c646b;
  --text:          #eef1f3;
  --text-dim:      #9ea7ae;
  --rust:          #b6541f;
  --rust-bright:   #d9701f;
  --rust-dim:      #7a3c19;
  --radius:        14px;
  --wrap:          1180px;
  --ease:          cubic-bezier(.22,.61,.36,1);
}

*, *::before, *::after{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior: auto; }
  *, *::before, *::after{ animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

body{
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3{
  font-family: 'Oswald', 'Inter', sans-serif;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.01em;
  margin: 0;
  color: var(--text);
}

p{ margin: 0; }
a{ color: inherit; text-decoration: none; }
ul{ list-style: none; margin: 0; padding: 0; }
svg{ display: block; }

.wrap{
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 28px;
}

/* subtle grain overlay for an industrial, non-flat surface */
.grain{
  position: fixed; inset: 0; pointer-events: none; z-index: 999;
  opacity: 0.035; mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.eyebrow{
  font-family: 'JetBrains Mono', monospace;
  font-size: 12.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--rust-bright);
  margin: 0 0 12px;
}

.eyebrow::before{
  content: '// ';
  color: var(--steel-dim);
}

/* ---------- buttons ---------- */
.btn{
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 26px;
  border-radius: 3px;
  font-family: 'Oswald', sans-serif;
  font-size: 14.5px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .18s var(--ease), background .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease);
}
.btn:active{ transform: translateY(1px); }

.btn-solid{
  background: var(--rust);
  color: #fff5ee;
}
.btn-solid:hover{ background: var(--rust-bright); }

.btn-line{
  border-color: var(--line);
  color: var(--text);
}
.btn-line:hover{ border-color: var(--steel); }

.btn-ghost{
  border: 1px solid var(--line);
  color: var(--text);
  padding: 10px 18px;
  font-size: 13.5px;
}
.btn-ghost:hover{ border-color: var(--rust); color: var(--rust-bright); }

.btn-block{ width: 100%; }

/* ---------- header ---------- */
.site-header{
  position: sticky; top: 0; z-index: 100;
  background: rgba(16,18,20,0.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line-soft);
}
.header-inner{
  display: flex; align-items: center; justify-content: space-between;
  height: 72px;
}
.brand{ display: flex; align-items: center; gap: 10px; color: var(--text); }
.brand-mark{ color: var(--rust-bright); display: inline-flex; }
.brand-text{
  font-family: 'Oswald', sans-serif;
  font-weight: 600;
  font-size: 20px;
  letter-spacing: 0.08em;
}
.nav{ display: flex; gap: 34px; }
.nav a{
  font-size: 14.5px;
  color: var(--text-dim);
  position: relative;
  padding: 6px 0;
  transition: color .18s var(--ease);
}
.nav a:hover{ color: var(--text); }
.nav a::after{
  content: ''; position: absolute; left: 0; right: 0; bottom: 0; height: 1px;
  background: var(--rust); transform: scaleX(0); transform-origin: left;
  transition: transform .22s var(--ease);
}
.nav a:hover::after{ transform: scaleX(1); }

.header-cta{ display: inline-flex; }

.burger{
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  width: 40px; height: 40px; background: none; border: 1px solid var(--line);
  border-radius: 3px; cursor: pointer;
}
.burger span{ display:block; height: 1.5px; width: 18px; margin: 0 auto; background: var(--text); transition: transform .2s var(--ease), opacity .2s var(--ease); }
.burger.open span:nth-child(1){ transform: translateY(6.5px) rotate(45deg); }
.burger.open span:nth-child(2){ opacity: 0; }
.burger.open span:nth-child(3){ transform: translateY(-6.5px) rotate(-45deg); }

/* ---------- hero ---------- */
.hero{
  position: relative;
  padding: 108px 0 90px;
  overflow: hidden;
  background: linear-gradient(180deg, #121417 0%, #101214 60%);
}
.hero-seam{
  position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background:
    linear-gradient(115deg, transparent 42%, rgba(255,255,255,0.025) 43%, rgba(255,255,255,0.025) 44%, transparent 45%),
    linear-gradient(115deg, transparent 58%, rgba(182,84,31,0.08) 59%, transparent 62%);
}
.hero-rings{
  position: absolute; right: -60px; top: 0; bottom: 0; width: 46%;
  z-index: 0; opacity: 0.55;
  -webkit-mask-image: linear-gradient(90deg, transparent, black 30%);
  mask-image: linear-gradient(90deg, transparent, black 30%);
}
.hero-inner{ position: relative; z-index: 1; max-width: 760px; }

.hero-title{
  font-size: clamp(38px, 5.6vw, 64px);
  line-height: 1.04;
  margin-bottom: 24px;
}
.hero-title-accent{ color: var(--rust-bright); }

.hero-sub{
  font-size: 17px;
  color: var(--text-dim);
  max-width: 560px;
  margin-bottom: 36px;
}

.hero-actions{ display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 56px; }

.hero-stats{
  display: flex; gap: 44px; flex-wrap: wrap;
  margin: 0; padding-top: 28px; border-top: 1px solid var(--line-soft);
}
.hero-stats dt{
  font-family: 'JetBrains Mono', monospace;
  font-size: 22px; color: var(--rust-bright); font-weight: 500;
}
.hero-stats dd{
  margin: 4px 0 0; font-size: 12.5px; color: var(--text-dim);
  text-transform: uppercase; letter-spacing: 0.06em;
}

/* ---------- section head shared ---------- */
.section-head{ max-width: 640px; margin-bottom: 52px; }
.section-head h2{ font-size: clamp(26px, 3.2vw, 36px); line-height: 1.15; }

section{ padding: 96px 0; }

/* ---------- services ---------- */
.services{ background: var(--bg); border-top: 1px solid var(--line-soft); }
.services-grid{
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  margin-bottom: 64px;
}
.service-card{
  background: var(--bg-panel);
  padding: 0 0 30px;
}
.service-photo{
  aspect-ratio: 4 / 3;
  overflow: hidden;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--line-soft);
}
.service-photo img{
  width: 100%; height: 100%; object-fit: cover;
  filter: grayscale(0.25) contrast(1.05);
  transform: scale(1.01);
  transition: transform .5s var(--ease), filter .5s var(--ease);
}
.service-card:hover .service-photo img{
  transform: scale(1.06);
  filter: grayscale(0) contrast(1.08);
}
.service-card h3{ font-size: 18px; margin: 0 30px 10px; letter-spacing: 0.01em; }
.service-card p{ color: var(--text-dim); font-size: 14.5px; margin: 0 30px; }

.cooperation{
  background: var(--bg-panel-2);
  border: 1px solid var(--line-soft);
  border-left: 3px solid var(--rust);
  border-radius: 4px;
  padding: 36px 38px;
}
.cooperation h3{
  font-size: 19px; margin-bottom: 20px; font-weight: 600; letter-spacing: 0.02em;
}
.cooperation-list{ display: grid; gap: 14px; }
.cooperation-list li{
  display: flex; gap: 14px; align-items: flex-start;
  color: var(--text-dim); font-size: 15px; line-height: 1.5;
}
.marker{
  flex: 0 0 auto; width: 8px; height: 8px; margin-top: 6px;
  background: var(--rust-bright); border-radius: 1px;
  transform: rotate(45deg);
}

/* ---------- range / assortment ---------- */
.range{ background: var(--bg-panel); border-top: 1px solid var(--line-soft); }

.range-head{
  display: flex; align-items: flex-end; justify-content: space-between;
  gap: 24px; flex-wrap: wrap;
}
.tag{
  flex: 0 0 auto;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 7px 14px; border-radius: 3px; border: 1px solid var(--line);
  margin-bottom: 4px;
  white-space: nowrap;
}
.tag-used{ color: var(--steel); border-color: var(--line); }
.tag-new{ color: #8fbf78; border-color: #33502c; background: rgba(143,191,120,0.06); }

.range-grid{
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px;
  background: var(--line-soft); border: 1px solid var(--line-soft);
}
.range-card{
  position: relative;
  background: var(--bg);
  padding-bottom: 24px;
  transition: background .2s var(--ease);
}
.range-card:hover{ background: #15171a; }
.range-photo{
  aspect-ratio: 4 / 3;
  overflow: hidden;
  margin-bottom: 20px;
}
.range-photo img{
  width: 100%; height: 100%; object-fit: cover;
  filter: grayscale(0.3) contrast(1.05);
  transform: scale(1.01);
  transition: transform .5s var(--ease), filter .5s var(--ease);
}
.range-card:hover .range-photo img{
  transform: scale(1.06);
  filter: grayscale(0) contrast(1.08);
}
.range-index{
  position: absolute; top: 14px; right: 16px;
  font-family: 'JetBrains Mono', monospace; font-size: 11.5px; color: #eef1f3;
  background: rgba(16,18,20,0.55);
  padding: 2px 7px; border-radius: 2px;
  backdrop-filter: blur(2px);
}
.range-card h3{ font-size: 15.5px; margin: 0 20px 8px; letter-spacing: 0.01em; }
.range-card p{ font-size: 13px; color: var(--text-dim); line-height: 1.5; margin: 0 20px; }

/* lumber variant — visually distinct from б/у metal grid */
.range-lumber{ background: var(--bg); }
.range-lumber-note{
  color: var(--text-dim); font-size: 14.5px; margin: -32px 0 32px;
}
.range-grid-lumber{
  grid-template-columns: repeat(2, 1fr);
}
.range-card-lumber{ background: var(--bg-panel); }
.range-card-lumber:hover{ background: var(--bg-panel-2); }
.range-card-lumber .range-photo{ aspect-ratio: 16 / 10; }
.range-card-lumber .range-photo img{ filter: none; }
.range-card-lumber h3{ font-size: 17px; }

/* ---------- why ---------- */
/* ---------- sand ---------- */
.sand{ background: var(--bg-panel); border-top: 1px solid var(--line-soft); }
.sand-inner{
  display: grid; grid-template-columns: 0.85fr 1.15fr; gap: 56px; align-items: center;
}
.sand-visual{
  aspect-ratio: 1 / 1;
  background: var(--bg);
  border: 1px solid var(--line-soft);
  border-radius: 4px;
  overflow: hidden;
}
.sand-visual img{
  width: 100%; height: 100%; object-fit: cover;
  filter: grayscale(0.25) contrast(1.05);
  transform: scale(1.01);
  transition: transform .5s var(--ease), filter .5s var(--ease);
}
.sand-visual:hover img{
  transform: scale(1.06);
  filter: grayscale(0) contrast(1.08);
}
.sand-content h2{ font-size: clamp(26px, 3.2vw, 34px); margin-bottom: 18px; }
.sand-lead{ color: var(--text-dim); font-size: 15.5px; max-width: 480px; margin-bottom: 26px; }
.sand-list{ display: grid; gap: 14px; margin-bottom: 32px; }
.sand-list li{
  display: flex; gap: 14px; align-items: flex-start;
  color: var(--text-dim); font-size: 15px; line-height: 1.5;
}

.range-lead{
  color: var(--text-dim); font-size: 15.5px; max-width: 620px; margin-top: 14px;
}

/* ---------- faq ---------- */
.faq{ background: var(--bg-panel); border-top: 1px solid var(--line-soft); }
.faq-list{ display: grid; gap: 1px; background: var(--line-soft); border: 1px solid var(--line-soft); max-width: 820px; }
.faq-item{
  background: var(--bg);
  padding: 20px 24px;
}
.faq-item summary{
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-family: 'Oswald', sans-serif;
  font-size: 16px;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--text);
}
.faq-item summary::-webkit-details-marker{ display: none; }
.faq-item summary::after{
  content: '+';
  flex: 0 0 auto;
  font-family: 'JetBrains Mono', monospace;
  font-size: 20px;
  color: var(--rust-bright);
  transition: transform .2s var(--ease);
}
.faq-item[open] summary::after{ transform: rotate(45deg); }
.faq-item p{
  color: var(--text-dim);
  font-size: 14.5px;
  line-height: 1.6;
  margin-top: 14px;
  max-width: 680px;
}

.contact-address{ font-style: normal; }

.why{ background: var(--bg); border-top: 1px solid var(--line-soft); }
.why-grid{
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 42px 48px;
}
.why-num{
  display: block;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px; color: var(--rust-bright);
  margin-bottom: 14px;
}
.why-item h3{ font-size: 18px; margin-bottom: 10px; }
.why-item p{ color: var(--text-dim); font-size: 14.5px; max-width: 420px; }

/* ---------- contacts ---------- */
.contacts{ background: var(--bg-panel); border-top: 1px solid var(--line-soft); }
.contacts-inner{
  display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 64px;
  align-items: start;
}
.contacts h2{ font-size: clamp(26px, 3.2vw, 34px); margin-bottom: 18px; }
.contacts-lead{ color: var(--text-dim); font-size: 15.5px; max-width: 440px; margin-bottom: 36px; }

.manager-card{
  display: flex; align-items: center; gap: 16px;
  padding: 18px 20px;
  background: var(--bg-panel-2);
  border: 1px solid var(--line-soft);
  border-radius: 4px;
  margin-bottom: 28px;
  max-width: 360px;
}
.manager-avatar{
  width: 46px; height: 46px; border-radius: 50%;
  background: linear-gradient(145deg, var(--rust), var(--rust-dim));
  display: flex; align-items: center; justify-content: center;
  font-family: 'Oswald', sans-serif; font-weight: 600; font-size: 14px; color: #fff5ee;
  flex: 0 0 auto;
}
.manager-name{ font-size: 16px; font-weight: 600; }
.manager-role{ font-size: 13px; color: var(--text-dim); margin-top: 2px; }

.contact-list{ display: grid; gap: 18px; max-width: 360px; }
.contact-list li{ display: flex; flex-direction: column; gap: 4px; }
.contact-label{
  font-family: 'JetBrains Mono', monospace; font-size: 11.5px;
  color: var(--steel-dim); text-transform: uppercase; letter-spacing: 0.08em;
}
.contact-value{
  font-family: 'JetBrains Mono', monospace; font-size: 17px; color: var(--text);
  transition: color .18s var(--ease);
}
.contact-value:hover{ color: var(--rust-bright); }

/* form */
.contact-form{
  background: var(--bg);
  border: 1px solid var(--line-soft);
  border-radius: 4px;
  padding: 34px;
}
.contact-form h3{ font-size: 18px; margin-bottom: 22px; }
.field{ display: block; margin-bottom: 18px; }
.field span{
  display: block; font-size: 12.5px; color: var(--text-dim);
  text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 8px;
}
.field input, .field textarea{
  width: 100%;
  background: var(--bg-panel-2);
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 12px 14px;
  color: var(--text);
  font-family: 'Inter', sans-serif;
  font-size: 14.5px;
  resize: vertical;
  transition: border-color .18s var(--ease);
}
.field input:focus, .field textarea:focus{
  outline: none; border-color: var(--rust);
}
.field input::placeholder, .field textarea::placeholder{ color: var(--steel-dim); }

.form-note{
  margin-top: 14px; font-size: 13px; color: var(--text-dim); min-height: 18px;
}
.form-note.success{ color: #7dbf8a; }
.form-note.error{ color: #d97a6a; }

/* ---------- footer ---------- */
.site-footer{ border-top: 1px solid var(--line-soft); padding: 34px 0; }
.footer-inner{
  display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap;
}
.brand-footer{ color: var(--steel); }
.brand-footer .brand-text{ font-size: 16px; }
.footer-copy{ font-size: 13px; color: var(--steel-dim); flex: 1 1 320px; }
.footer-phone{
  font-family: 'JetBrains Mono', monospace; font-size: 14px; color: var(--text-dim);
}
.footer-phone:hover{ color: var(--rust-bright); }

/* ---------- focus visibility ---------- */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible{
  outline: 2px solid var(--rust-bright);
  outline-offset: 2px;
}

/* ---------- reveal-on-scroll ---------- */
.reveal{ opacity: 0; transform: translateY(18px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.reveal.in{ opacity: 1; transform: translateY(0); }

/* ==========================================================
   Responsive
   ========================================================== */
@media (max-width: 980px){
  .services-grid{ grid-template-columns: 1fr; }
  .range-grid{ grid-template-columns: repeat(2, 1fr); }
  .range-grid-lumber{ grid-template-columns: 1fr; }
  .why-grid{ grid-template-columns: 1fr; }
  .contacts-inner{ grid-template-columns: 1fr; gap: 44px; }
  .hero-rings{ width: 60%; opacity: 0.35; }
  .sand-inner{ grid-template-columns: 1fr; gap: 32px; }
  .sand-visual{ aspect-ratio: 16 / 9; max-height: 240px; }
}

@media (max-width: 720px){
  .nav{
    position: fixed; top: 72px; left: 0; right: 0;
    background: #101214f2; backdrop-filter: blur(10px);
    flex-direction: column; gap: 0;
    border-bottom: 1px solid var(--line-soft);
    max-height: 0; overflow: hidden;
    transition: max-height .28s var(--ease);
  }
  .nav.open{ max-height: 320px; }
  .nav a{ padding: 16px 28px; border-top: 1px solid var(--line-soft); }
  .header-cta{ display: none; }
  .burger{ display: flex; }

  .hero{ padding: 78px 0 64px; }
  .hero-rings{ display: none; }
  .hero-actions{ flex-direction: column; align-items: stretch; }
  .hero-stats{ gap: 28px; }

  section{ padding: 68px 0; }
  .range-grid{ grid-template-columns: 1fr 1fr; }
  .cooperation{ padding: 28px 24px; }
}

@media (max-width: 460px){
  .range-grid{ grid-template-columns: 1fr; }
}