:root{
  --bg: #0b0b0b;
  --fg: #f2f2f2;
  --muted: rgba(242,242,242,.72);
  --line: rgba(242,242,242,.20);
  --max: 1100px;
}

*{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  background: var(--bg);
  color: var(--fg);
}

/* Topbar */
.topbar{
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  backdrop-filter: blur(8px);
  background: linear-gradient(to bottom, rgba(0,0,0,.55), rgba(0,0,0,0));
  border-bottom: 1px solid rgba(255,255,255,.06);
}
.wrap{
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto;
}
.topbar__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding: 16px 0;
}

.brand{
  display:flex;
  align-items:center;
  gap:10px;
  text-decoration:none;
  color: var(--fg);
  letter-spacing:.2px;
}
.brand__mark{
  width:10px;height:10px;border-radius:999px;
  background: var(--fg);
  opacity:.9;
}
.brand__name{
  font-weight: 650;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: .14em;
}

/* Menu */
.menu{ display:flex; gap:18px; align-items:center; }
.menu a{
  color: var(--fg);
  text-decoration:none;
  font-size: 13px;
  letter-spacing: .08em;
  text-transform: uppercase;
  opacity:.85;
  padding: 8px 6px;
  border-bottom: 1px solid transparent;
}
.menu a:hover{ opacity:1; border-bottom-color: var(--line); }

/* Burger */
.burger{
  display:none;
  width:44px;height:40px;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(0,0,0,.25);
  border-radius: 10px;
  cursor:pointer;
}
.burger span{
  display:block;
  width:18px;height:2px;
  background: var(--fg);
  margin: 4px auto;
  opacity:.9;
}

/* Sections */
.section{
  min-height: 100svh;
  position: relative;
  display:flex;
  align-items:center;
  padding: 96px 0 64px;
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}
.overlay{
  position:absolute; inset:0;
  background:
    radial-gradient(1200px 600px at 15% 20%, rgba(0,0,0,.25), rgba(0,0,0,.78)),
    linear-gradient(to bottom, rgba(0,0,0,.35), rgba(0,0,0,.78));
}
.content{ position: relative; z-index: 1; }

.kicker{
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  opacity: .85;
  margin-bottom: 14px;
}
.title{
  font-size: clamp(34px, 5vw, 56px);
  line-height: 1.05;
  margin: 0 0 16px;
  font-weight: 680;
  letter-spacing: .01em;
}
.h2{
  font-size: clamp(26px, 3.3vw, 40px);
  line-height: 1.12;
  margin: 0 0 10px;
  font-weight: 650;
}
.tagline{
  margin: 0 0 18px;
  font-style: italic;
  color: rgba(255,255,255,.78);
  letter-spacing: .02em;
}
.lead{
  max-width: 62ch;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.7;
  margin: 0 0 18px;
}

/* Buttons */
.actions{ display:flex; gap:12px; flex-wrap:wrap; }
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  text-decoration:none;
  color: var(--bg);
  background: var(--fg);
  border: 1px solid rgba(255,255,255,.18);
  padding: 10px 14px;
  border-radius: 999px;
  font-size: 13px;
  letter-spacing: .08em;
  text-transform: uppercase;
  transition: transform .15s ease;
}
.btn--ghost{
  background: transparent;
  color: var(--fg);
  border-color: rgba(255,255,255,.25);
}
.btn:hover{ transform: translateY(-1px); }

/* Scroll hint */
.scrollHint{
  display:inline-block;
  margin-top: 26px;
  color: rgba(255,255,255,.72);
  text-decoration:none;
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  border-bottom: 1px solid rgba(255,255,255,.18);
  padding-bottom: 6px;
}

/* Cards */
.card{
  margin-top: 18px;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(0,0,0,.25);
  border-radius: 18px;
  padding: 18px;
  max-width: 820px;
}
.card__title{
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  opacity: .9;
  margin-bottom: 12px;
}
.chips{ display:flex; flex-wrap:wrap; gap:10px; }
.chip{
  border: 1px solid rgba(255,255,255,.18);
  background: rgba(255,255,255,.06);
  padding: 8px 10px;
  border-radius: 999px;
  font-size: 13px;
  color: rgba(255,255,255,.9);
}

/* Lists */
.list{
  list-style:none;
  padding:0;
  margin: 18px 0 0;
  max-width: 840px;
  border-top: 1px solid rgba(255,255,255,.16);
}
.list li{
  padding: 14px 0;
  border-bottom: 1px solid rgba(255,255,255,.14);
  color: rgba(255,255,255,.88);
  letter-spacing:.01em;
}
.list strong{ color: rgba(255,255,255,.98); }

/* Services grid */
.serviceGrid{
  margin-top: 18px;
  display:grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  max-width: 980px;
}
.serviceCard{
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(0,0,0,.22);
  border-radius: 18px;
  padding: 16px;
}
.serviceTitle{
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  opacity: .9;
  margin-bottom: 10px;
}
.serviceText{
  color: rgba(255,255,255,.82);
  line-height: 1.6;
  margin-bottom: 12px;
}
.serviceLink{
  color: rgba(255,255,255,.9);
  text-decoration:none;
  border-bottom: 1px solid rgba(255,255,255,.18);
  padding-bottom: 4px;
}
.serviceLink:hover{ border-bottom-color: rgba(255,255,255,.45); }

/* Why grid */
.whyGrid{
  margin-top: 18px;
  display:grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  max-width: 980px;
}
.whyItem{
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(0,0,0,.22);
  border-radius: 18px;
  padding: 16px;
}
.whyItem h3{
  margin: 0 0 8px;
  font-size: 16px;
  letter-spacing: .02em;
}
.whyItem p{
  margin: 0;
  color: rgba(255,255,255,.78);
  line-height: 1.65;
}
.closingLine{
  margin-top: 18px;
  max-width: 72ch;
  color: rgba(255,255,255,.82);
  border-top: 1px solid rgba(255,255,255,.14);
  padding-top: 16px;
}

/* Contact */
.contactGrid{
  display:grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  max-width: 900px;
  margin-top: 18px;
}
.contactBlock{
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(0,0,0,.22);
  border-radius: 16px;
  padding: 14px 16px;
}
.label{
  font-size: 11px;
  letter-spacing: .22em;
  text-transform: uppercase;
  opacity: .8;
  margin-bottom: 8px;
}
.value, .value a{
  color: rgba(255,255,255,.88);
  text-decoration:none;
  line-height: 1.55;
}
.value a:hover{ text-decoration: underline; }

.footer{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap: 12px;
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid rgba(255,255,255,.14);
  color: rgba(255,255,255,.7);
  font-size: 13px;
}
.footer a{ color: rgba(255,255,255,.85); text-decoration:none; }
.footer a:hover{ text-decoration: underline; }

/* Background images */
.section--intro{      background-image: url("images/intro.jpg"); }
.section--about{      background-image: url("images/about.jpg"); }
.section--services{   background-image: url("images/services.jpg"); }
.section--structural{ background-image: url("images/structural.jpg"); }
.section--steel{      background-image: url("images/steel.jpg"); }
.section--bim{        background-image: url("images/bim.jpg"); }
.section--why{        background-image: url("images/why.jpg"); }
.section--contact{    background-image: url("images/contact.jpg"); }

/* Responsive */
@media (max-width: 920px){
  .section{ background-attachment: scroll; }
  .serviceGrid{ grid-template-columns: 1fr; }
  .whyGrid{ grid-template-columns: 1fr; }
  .contactGrid{ grid-template-columns: 1fr; }
}
@media (max-width: 820px){
  .menu{
    position: absolute;
    top: 62px; right: 24px;
    display:none;
    flex-direction: column;
    gap: 10px;
    padding: 12px;
    border: 1px solid rgba(255,255,255,.14);
    background: rgba(0,0,0,.65);
    border-radius: 14px;
    min-width: 190px;
  }
  .menu.isOpen{ display:flex; }
  .burger{ display:block; }
}