:root{
  --bg:#212529;
  --bg2:#181b1e;
  --panel:#202428;
  --text:#f1f3f4;
  --muted:#a5abb0;
  --line:#3a4045;
  --orange:#FF6B00;
  --max:1180px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font-family:"Montserrat",Arial,sans-serif;line-height:1.55}
a{color:inherit;text-decoration:none}
button,input,textarea{font:inherit}
.container{width:min(var(--max),calc(100% - 48px));margin:auto}
.header{position:absolute;z-index:20;top:0;left:0;right:0;border-bottom:1px solid rgba(255,255,255,.09);background:rgba(20,23,26,.35);backdrop-filter:blur(8px)}
.header__inner{min-height:82px;display:flex;align-items:center;gap:34px}
.logo{display:flex;align-items:center;gap:12px;min-width:250px}
.logo__mark{display:grid;place-items:center;width:38px;height:38px;border:2px solid var(--orange);color:var(--orange);font-weight:700;font-size:22px}
.logo strong{display:block;font-size:20px;letter-spacing:.04em}
.logo small{display:block;color:var(--muted);font-size:7px;line-height:1.3;letter-spacing:.05em;margin-top:3px}
.nav{display:flex;gap:27px;margin-left:auto}
.nav a{font-size:11px;text-transform:uppercase;color:#d5d9dc;transition:.2s}
.nav a:hover{color:var(--orange)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:24px;min-height:54px;padding:0 25px;background:var(--orange);border:1px solid var(--orange);color:#fff;text-transform:uppercase;font-size:11px;font-weight:700;letter-spacing:.02em;transition:.2s}
.btn:hover{background:#e95f00;transform:translateY(-1px)}
.btn--small{min-height:42px;padding:0 18px;margin-left:10px}
.nav-toggle{display:none;background:none;border:0;color:#fff}
.hero{min-height:690px;position:relative;overflow:hidden;display:flex;align-items:center;background:#171a1d}
.hero__bg{position:absolute;inset:0;background-image:linear-gradient(90deg,#171a1d 5%,rgba(23,26,29,.96) 30%,rgba(23,26,29,.25) 68%,rgba(23,26,29,.55)),url("assets/hero-refinery.jpg");background-size:cover;background-position:center right;filter:saturate(.65)}
.hero__content{position:relative;z-index:2;padding-top:70px}
.hero__copy{max-width:610px}
.eyebrow{color:var(--orange);text-transform:uppercase;font-size:10px;font-weight:600;letter-spacing:.12em;margin:0 0 17px}
h1,h2,h3,p{margin-top:0}
h1{font-size:clamp(42px,5.2vw,70px);line-height:1.08;letter-spacing:-.035em;margin-bottom:25px}
h1 span{color:var(--orange)}
.hero__text{max-width:500px;color:#c0c5c9;font-size:15px}
.hero__actions{display:flex;align-items:center;gap:28px;margin-top:34px}
.text-link{font-size:11px;text-transform:uppercase;color:#cfd3d6}
.text-link span{color:var(--orange);margin-left:10px}
.hero__line{position:absolute;bottom:0;left:0;right:0;height:1px;background:var(--orange);opacity:.55}
.section{padding:100px 0}
.section-head{margin-bottom:42px}
.section-head--center{text-align:center}
.section-head h2,.contacts h2,.cta h2{font-size:clamp(28px,3.2vw,42px);line-height:1.1;letter-spacing:-.025em;margin-bottom:14px}
.section-head>p:last-child{color:var(--muted);max-width:650px}
.section-head--center>p:last-child{margin-inline:auto}
.cards{display:grid;gap:14px}
.cards--4{grid-template-columns:repeat(4,1fr)}
.card{min-height:275px;border:1px solid var(--line);padding:30px;background:linear-gradient(145deg,#23272b,#1b1e21);transition:.25s}
.card:hover{border-color:var(--orange);transform:translateY(-3px)}
.card h3{font-size:14px;text-transform:uppercase;margin:25px 0 12px}
.card p{color:var(--muted);font-size:12px}
.icon{width:60px;height:60px;position:relative;color:var(--orange)}
.icon:before,.icon:after{content:"";position:absolute;border:1px solid currentColor}
.icon--dome:before{width:48px;height:27px;border-radius:50% 50% 0 0;bottom:8px;left:4px}
.icon--dome:after{width:42px;height:42px;border-radius:50%;left:7px;top:2px;border-bottom-color:transparent}
.icon--mast:before{width:8px;height:54px;left:26px;top:2px;transform:skew(-8deg)}
.icon--mast:after{width:46px;height:40px;left:7px;top:9px;border-top:0;transform:skewY(-25deg)}
.icon--net:before{inset:4px;background:repeating-linear-gradient(0deg,transparent 0 9px,currentColor 10px 11px),repeating-linear-gradient(90deg,transparent 0 9px,currentColor 10px 11px)}
.icon--tools:before{width:42px;height:10px;left:8px;top:25px;transform:rotate(45deg);border-radius:5px}
.icon--tools:after{width:20px;height:20px;left:28px;top:8px;border-radius:50%}
.section--feature{background:#1c2023;border-top:1px solid #30353a;border-bottom:1px solid #30353a}
.feature{display:grid;grid-template-columns:1.25fr .75fr;border:1px solid var(--line)}
.feature__visual{min-height:470px;border-right:1px solid var(--line);position:relative}
.feature__image{position:absolute;inset:0;overflow:hidden;background:radial-gradient(circle at 55% 55%,#3a4146 0 2%,#22282c 45%,#15181b 80%)}
.mesh{position:absolute;inset:13% 7% 28%;background:repeating-linear-gradient(20deg,transparent 0 17px,rgba(255,255,255,.13) 18px 19px),repeating-linear-gradient(160deg,transparent 0 17px,rgba(255,255,255,.13) 18px 19px);clip-path:polygon(0 34%,50% 0,100% 35%,100% 80%,50% 35%,0 80%);opacity:.75}
.mast{position:absolute;bottom:18%;width:6px;background:linear-gradient(90deg,#596168,#171a1d,#596168);height:58%;box-shadow:0 0 0 1px rgba(255,255,255,.12)}
.mast:after{content:"";position:absolute;inset:0 -13px;background:repeating-linear-gradient(35deg,transparent 0 15px,rgba(255,255,255,.28) 16px 17px),repeating-linear-gradient(-35deg,transparent 0 15px,rgba(255,255,255,.28) 16px 17px)}
.mast--1{left:18%}.mast--2{left:50%;height:70%}.mast--3{right:18%;height:52%}
.tank{position:absolute;bottom:14%;width:18%;height:23%;border:2px solid #737b80;border-radius:50% 50% 10% 10%;background:linear-gradient(90deg,#202427,#4a5054,#202427)}
.tank:after{content:"";position:absolute;left:-2px;right:-2px;top:-8px;height:12px;border:2px solid #737b80;border-radius:50%}
.tank--1{left:28%}.tank--2{left:55%}
.feature__caption{position:absolute;bottom:17px;left:20px;color:var(--orange);font-size:9px;letter-spacing:.12em}
.slider-controls{position:absolute;bottom:17px;left:20px;right:20px;display:flex;justify-content:space-between;align-items:center;z-index:3}
.slider-btn{width:38px;height:38px;border:1px solid var(--line);background:rgba(20,23,26,.75);color:#fff;cursor:pointer}
.dots{display:flex;gap:7px}
.dot{width:7px;height:7px;border:0;border-radius:50%;background:#687078;padding:0;cursor:pointer}
.dot.is-active{background:var(--orange)}
.feature__info{padding:45px 42px}
.feature__lead{font-size:16px;color:#d8dcdf;margin-bottom:30px}
.check-list{list-style:none;padding:0;margin:0}
.check-list li{position:relative;padding:0 0 17px 28px;color:#b9bec2;font-size:12px}
.check-list li:before{content:"✓";position:absolute;left:0;top:0;color:var(--orange);font-weight:700}
.spec{border-top:1px solid var(--line);margin-top:25px;padding-top:22px;display:flex;justify-content:space-between;align-items:end}
.spec span{font-size:9px;color:var(--muted);letter-spacing:.1em}
.spec strong{font-size:32px;color:var(--orange)}
.advantages{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.advantages article{padding:30px;border-right:1px solid var(--line)}
.advantages article:last-child{border-right:0}
.adv-num{color:var(--orange);font-size:12px;font-weight:700}
.advantages h3{font-size:13px;margin:15px 0 10px}
.advantages p{font-size:11px;color:var(--muted)}
.cta{padding:55px 0;background:#191c1f;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.cta__inner{border:1px solid var(--orange);padding:28px 32px;display:flex;align-items:center;justify-content:space-between;gap:30px}
.cta h2{margin-bottom:7px}
.cta p:last-child{color:var(--muted);margin:0;font-size:12px}
.contacts__grid{display:grid;grid-template-columns:1fr 1fr;gap:70px}
.contacts__text{color:var(--muted);max-width:480px}
.form{display:grid;gap:15px}
.form label{display:grid;gap:7px;color:#d6dadd;font-size:10px;text-transform:uppercase;letter-spacing:.06em}
.form input,.form textarea{width:100%;border:1px solid var(--line);background:#191c1f;color:#fff;padding:14px 15px;outline:0;resize:vertical}
.form input:focus,.form textarea:focus{border-color:var(--orange)}
.form small{font-size:9px;color:#7e858a}
.footer{border-top:1px solid var(--line);padding:35px 0;background:#181b1e}
.footer__inner{display:flex;align-items:center;justify-content:space-between;gap:30px}
.footer__contact{display:flex;gap:25px;color:#c7ccd0;font-size:11px}
.footer__inner>p{font-size:10px;color:#747b80;margin:0}
@media(max-width:900px){
  .nav{display:none;position:absolute;top:82px;left:0;right:0;background:#171a1d;padding:20px 24px;border-bottom:1px solid var(--line);flex-direction:column}
  .nav.is-open{display:flex}
  .nav-toggle{display:flex;margin-left:auto;width:34px;flex-direction:column;gap:7px;cursor:pointer}
  .nav-toggle span{height:1px;background:#fff;width:25px}
  .btn--small{margin-left:0}
  .cards--4{grid-template-columns:repeat(2,1fr)}
  .feature{grid-template-columns:1fr}
  .feature__visual{min-height:390px;border-right:0;border-bottom:1px solid var(--line)}
  .advantages{grid-template-columns:repeat(2,1fr)}
  .advantages article:nth-child(2){border-right:0}
  .advantages article:nth-child(-n+2){border-bottom:1px solid var(--line)}
}
@media(max-width:620px){
  .container{width:min(var(--max),calc(100% - 32px))}
  .header__inner{gap:10px}
  .logo{min-width:0}
  .logo strong{font-size:16px}
  .logo small{display:none}
  .header .btn{font-size:9px;padding:0 11px;min-height:38px}
  .hero{min-height:680px}
  .hero__bg{background-position:65% center}
  h1{font-size:39px}
  .hero__text{font-size:13px}
  .hero__actions{align-items:flex-start;flex-direction:column;gap:18px}
  .section{padding:70px 0}
  .cards--4{grid-template-columns:1fr}
  .card{min-height:220px}
  .feature__info{padding:30px 22px}
  .feature__visual{min-height:320px}
  .advantages{grid-template-columns:1fr}
  .advantages article{border-right:0!important;border-bottom:1px solid var(--line)!important}
  .advantages article:last-child{border-bottom:0!important}
  .cta__inner{align-items:flex-start;flex-direction:column;padding:24px}
  .contacts__grid{grid-template-columns:1fr;gap:35px}
  .footer__inner{align-items:flex-start;flex-direction:column}
  .footer__contact{flex-direction:column;gap:8px}
}