@font-face{font-family:"DM Sans";font-style:normal;font-weight:400 700;font-display:swap;src:url("/fonts/dm-sans-latin-9fea608a947e.woff2") format("woff2")}
@font-face{font-family:"Libre Caslon Display";font-style:normal;font-weight:400;font-display:swap;src:url("/fonts/libre-caslon-display-latin-84267e937417.woff2") format("woff2")}
:root{--green:#052e25;--green-dark:#031e19;--green-mid:#123c31;--cream:#f4f0e8;--cream-2:#e9e1d3;--white:#fffdfa;--orange:#da7d4c;--orange-light:#f2a06c;--line:rgba(5,46,37,.18);--muted:#5e6b67;--serif:"Libre Caslon Display",Georgia,serif;--sans:"DM Sans",Arial,sans-serif}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--cream);color:var(--green);font:17px/1.72 var(--sans);overflow-x:clip}
main{overflow:clip}
img{display:block;max-width:100%}
a{color:inherit}
.wrap{width:min(1240px,calc(100% - 64px));margin-inline:auto}
.eyebrow{color:var(--orange);font-size:.69rem;line-height:1.25;letter-spacing:.18em;text-transform:uppercase;font-weight:700}
h1,h2,h3{margin:0;font-family:var(--serif);font-weight:400;line-height:1.03;letter-spacing:-.035em}
h1{font-size:clamp(3.8rem,6.2vw,7rem)}
h2{font-size:clamp(2.7rem,4.5vw,5rem)}
h3{font-size:clamp(1.55rem,2.2vw,2.35rem)}
p{margin:0 0 1.25rem}
.section-heading{display:grid;grid-template-columns:minmax(0,1fr) minmax(280px,.62fr);gap:80px;align-items:end;margin-bottom:58px}
.section-heading h2{margin-top:15px}
.section-heading>p{margin:0;padding-top:27px;border-top:1px solid var(--line);color:var(--muted)}
.section-heading.light>p{border-color:rgba(255,255,255,.22);color:rgba(255,255,255,.73)}
.actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:32px}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:14px 21px;border-radius:2px;text-decoration:none;text-transform:uppercase;letter-spacing:.09em;font-size:.7rem;font-weight:700}
.btn.primary{background:var(--orange);color:var(--green)}
.btn.ghost{border:1px solid rgba(255,255,255,.5);color:var(--white)}
.btn.dark-btn{background:var(--green);color:var(--white)}

/* Hero: overlaid on wide screens, deliberately stacked on narrow screens. */
.hero{position:relative;isolation:isolate;min-height:clamp(610px,42.7vw,820px);display:flex;align-items:center;background:var(--green-dark);color:var(--white);overflow:hidden}
.hero-media,.hero-shade{position:absolute;inset:0}
.hero-media{z-index:-2}
.hero-media img{width:100%;height:100%;object-fit:cover;object-position:center center}
.hero-shade{z-index:-1;background:linear-gradient(90deg,rgba(3,30,25,.98) 0,rgba(3,30,25,.91) 27%,rgba(3,30,25,.52) 48%,rgba(3,30,25,.1) 69%,rgba(3,30,25,0) 100%)}
.hero-inner{display:flex;align-items:center;min-height:inherit}
.hero-copy{width:min(770px,60%);padding:76px 0 82px}
.hero h1{margin:18px 0 25px;max-width:760px}
.hero-lead{max-width:690px;font:400 clamp(1.35rem,2vw,2.05rem)/1.27 var(--serif)}
.hero-lead em{color:var(--orange-light)}
.hero-desc{max-width:670px;color:rgba(255,255,255,.84)}

/* Credential strip uses official files, including the supplied NICEIC mark without 70. */
.trust{padding:0;background:var(--white);border-bottom:1px solid var(--line)}
.trust-inner{width:min(1320px,calc(100% - 64px));min-height:106px;margin:auto;display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:44px}
.trust-points{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));height:100%}
.trust-points p{display:flex;align-items:center;gap:12px;min-height:106px;margin:0;padding:18px 26px;border-right:1px solid var(--line);font-size:.7rem;line-height:1.35;letter-spacing:.08em;text-transform:uppercase;font-weight:700}
.trust-points p:first-child{padding-left:0}
.trust-points span{color:var(--orange);font-size:.61rem;letter-spacing:.12em}
.trust-credentials{display:flex;align-items:center;justify-content:flex-end;gap:24px;min-width:224px}
.trust-credentials a{display:flex;align-items:center;justify-content:center;text-decoration:none}
.gas-mark img{width:48px;height:54px;object-fit:contain}
.niceic-mark span{display:block;width:128px;height:54px;overflow:hidden;background:#fff}
.niceic-mark img{display:block;width:128px;height:128px;max-width:none;object-fit:cover;transform:translateY(-37px)}

.intro,.choice-section,.plant,.permissions,.process,.coordination,.area,.faq{padding:clamp(88px,8vw,130px) 0}
.intro-grid,.choice-grid,.plant-grid,.permissions-grid,.coordination-grid{display:grid;grid-template-columns:minmax(0,1.08fr) minmax(0,.92fr);gap:92px;align-items:start}
.intro-grid h2,.choice-grid h2,.plant-grid h2,.permissions-grid h2,.coordination-grid h2{margin:15px 0 31px}
.intro-copy{padding-top:56px;border-top:1px solid var(--line)}
.facts{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;margin-top:50px;border:1px solid var(--line);background:var(--line)}
.facts>div{padding:27px 25px;background:var(--cream)}
.facts strong{display:block;font:400 2.15rem/1 var(--serif)}
.facts span{display:block;margin-top:8px;color:var(--muted);font-size:.65rem;line-height:1.45;letter-spacing:.095em;text-transform:uppercase}

.property-section{padding:clamp(88px,8vw,130px) 0;background:var(--cream-2)}
.property-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:1px;border:1px solid var(--line);background:var(--line)}
.property-grid article{min-height:330px;padding:38px;background:var(--cream-2)}
.property-grid span,.method-number{color:var(--orange);font-size:.64rem;line-height:1.4;letter-spacing:.13em;text-transform:uppercase;font-weight:700}
.property-grid h3{margin:44px 0 15px}
.property-grid p{margin:0;color:var(--muted);font-size:.92rem}

.choice-section{background:var(--white)}
.choice-grid>div:first-child>p{max-width:650px;color:var(--muted)}
.choices{padding-top:4px}
.choice{display:grid;grid-template-columns:118px 1fr;gap:27px;padding:29px 0;border-top:1px solid var(--line)}
.choice:last-child{border-bottom:1px solid var(--line)}
.choice>span{color:var(--orange);font-size:.66rem;letter-spacing:.11em;text-transform:uppercase;font-weight:700}
.choice h3{margin-bottom:10px;font-size:clamp(1.55rem,2vw,2rem)}
.choice p{margin:0;color:var(--muted);font-size:.9rem}

.systems{padding:clamp(92px,8vw,136px) 0;background:var(--green);color:var(--white)}
.system-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}
.method-card,.photo-card{min-height:560px;overflow:hidden}
.method-card{display:flex;flex-direction:column;justify-content:space-between;padding:42px;background:var(--orange);color:var(--green)}
.method-card h3{max-width:500px;margin:20px 0 16px;font-size:clamp(2.4rem,4vw,4.4rem)}
.method-card p{max-width:620px;margin:0;font-size:.94rem}
.photo-card{position:relative;background:var(--green-mid)}
.photo-card.wide{grid-column:1/-1;min-height:620px}
.photo-card picture,.photo-card img{position:absolute;inset:0;width:100%;height:100%}
.photo-card img{object-fit:cover}
.photo-card:after{content:"";position:absolute;inset:0;background:linear-gradient(0deg,rgba(2,29,23,.97),rgba(2,29,23,.58) 42%,rgba(2,29,23,.04) 78%)}
.card-copy{position:absolute;z-index:2;left:0;right:0;bottom:0;padding:38px 40px}
.card-copy h3{margin:9px 0 13px}
.card-copy p{max-width:740px;margin:0;color:rgba(255,255,255,.83);font-size:.9rem}

.media-split{display:grid;grid-template-columns:1fr 1fr;min-height:720px;padding:0;background:var(--green);color:var(--white)}
.media-split.reverse .media{order:2}
.media{min-width:0;min-height:640px}
.media picture,.media img{display:block;width:100%;height:100%}
.media img{object-fit:cover}
.media-copy{display:flex;flex-direction:column;justify-content:center;padding:82px clamp(42px,7vw,110px)}
.media-copy h2{margin:15px 0 30px;font-size:clamp(2.8rem,4.3vw,4.8rem)}
.media-copy p{color:rgba(255,255,255,.76)}
.media-split.finish{background:#143a31}
.media-split.wunda{background:var(--green-dark)}
.media-split.testing{background:#17342d}
.mini-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:13px 22px;margin-top:19px}
.mini-grid span{padding-top:13px;border-top:1px solid rgba(255,255,255,.25);font-size:.69rem;letter-spacing:.09em;text-transform:uppercase}

.plant{background:var(--cream)}
.plant-grid>div:first-child p{max-width:650px;color:var(--muted)}
.check-list{border-top:1px solid var(--line)}
.check-list>div{display:grid;grid-template-columns:45px 1fr;gap:18px;padding:20px 0;border-bottom:1px solid var(--line)}
.check-list b{color:var(--orange);font-size:.63rem;letter-spacing:.1em}
.check-list span{font-size:.9rem;font-weight:600}

.permissions{background:var(--white)}
.permissions-grid>div p{max-width:650px;color:var(--muted)}
.permissions aside{padding:42px;background:var(--orange);box-shadow:0 28px 70px rgba(5,46,37,.15)}
.permissions aside>span{font-size:.65rem;letter-spacing:.12em;text-transform:uppercase;font-weight:700}
.permissions ul{margin:24px 0 0;padding:0;list-style:none}
.permissions li{padding:14px 0;border-top:1px solid rgba(5,46,37,.25);font-size:.88rem;font-weight:600}

.test-sequence{display:flex;align-items:center;gap:12px;margin-top:25px;font-size:.63rem;letter-spacing:.1em;text-transform:uppercase;font-weight:700}
.test-sequence i{flex:1;height:1px;background:rgba(255,255,255,.28)}

.process{background:var(--cream)}
.process-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:1px;border:1px solid var(--line);background:var(--line)}
.process-grid article{min-height:250px;padding:31px 27px;background:var(--white)}
.process-grid article:last-child{background:var(--green);color:var(--white)}
.process-grid article>span{color:var(--orange);font-size:.63rem;letter-spacing:.13em;font-weight:700}
.process-grid h3{margin:40px 0 12px;font-size:1.55rem}
.process-grid p{margin:0;color:var(--muted);font-size:.81rem;line-height:1.55}
.process-grid article:last-child p{color:rgba(255,255,255,.7)}

.coordination{background:var(--orange)}
.coordination-grid>div:last-child{padding-top:58px;border-top:1px solid rgba(5,46,37,.3)}

.area{background:var(--cream)}
.area-grid{display:grid;grid-template-columns:minmax(0,1.08fr) minmax(330px,.92fr);gap:92px;align-items:start}
.area h2{margin:15px 0 31px}
.area p{color:var(--muted)}
.tags{display:flex;flex-wrap:wrap;gap:9px;margin-top:28px}
.tags span{padding:9px 13px;border:1px solid var(--line);border-radius:99px;font-size:.65rem;letter-spacing:.07em;text-transform:uppercase}
.area aside{padding:43px;background:var(--white);box-shadow:0 28px 70px rgba(5,46,37,.12)}
.area aside h3{margin:16px 0 22px;font-size:clamp(2.2rem,3.5vw,3.8rem)}

.related{padding:clamp(88px,8vw,130px) 0;background:var(--green-dark);color:var(--white)}
.related h2{max-width:870px;margin-top:15px}
.related-intro{max-width:760px;margin:28px 0 48px;color:rgba(255,255,255,.72)}
.related-grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));border-top:1px solid rgba(255,255,255,.22);border-left:1px solid rgba(255,255,255,.22)}
.related-grid a{display:flex;flex-direction:column;min-height:240px;padding:28px 25px;border-right:1px solid rgba(255,255,255,.22);border-bottom:1px solid rgba(255,255,255,.22);text-decoration:none;transition:background .2s,color .2s}
.related-grid a:hover,.related-grid a:focus-visible{background:var(--orange);color:var(--green)}
.related-grid span{color:var(--orange-light);font-size:.63rem;letter-spacing:.12em;text-transform:uppercase;font-weight:700}
.related-grid a:hover span,.related-grid a:focus-visible span{color:var(--green)}
.related-grid strong{display:block;margin:18px 0 32px;font:400 clamp(1.4rem,1.8vw,2rem)/1.08 var(--serif)}
.related-grid em{margin-top:auto;font-style:normal;font-size:.64rem;letter-spacing:.08em;text-transform:uppercase;font-weight:700}

.faq{background:var(--white)}
.faq details{padding:22px 0;border-top:1px solid var(--line)}
.faq details:last-child{border-bottom:1px solid var(--line)}
.faq summary{position:relative;padding-right:55px;cursor:pointer;list-style:none;font:400 1.48rem/1.25 var(--serif)}
.faq summary::-webkit-details-marker{display:none}
.faq summary:after{content:"+";position:absolute;right:6px;color:var(--orange);font-family:var(--sans)}
.faq details[open] summary:after{content:"−"}
.faq details p{max-width:880px;margin:18px 0 4px;color:var(--muted);font-size:.91rem}

.cta{padding:clamp(100px,10vw,155px) 0;background:var(--green);color:var(--white);text-align:center}
.cta h2{max-width:940px;margin:15px auto 28px}
.cta p{max-width:720px;margin-inline:auto;color:rgba(255,255,255,.72)}
.cta .actions{justify-content:center}

@media(max-width:1180px){
  .related-grid{grid-template-columns:repeat(3,minmax(0,1fr))}
  .hero-copy{width:min(720px,66%)}
}

@media(max-width:980px){
  .section-heading,.intro-grid,.choice-grid,.plant-grid,.permissions-grid,.coordination-grid,.area-grid{grid-template-columns:1fr;gap:42px}
  .intro-copy,.coordination-grid>div:last-child{padding-top:28px}
  .trust-inner{grid-template-columns:1fr;gap:0}
  .trust-points p{min-height:84px}
  .trust-credentials{justify-content:flex-start;padding:20px 0}
  .property-grid{grid-template-columns:1fr}
  .property-grid article{min-height:270px}
  .process-grid{grid-template-columns:repeat(2,1fr)}
  .hero-copy{width:min(650px,72%)}
  .media-split{grid-template-columns:1fr;min-height:0}
  .media-split.reverse .media{order:0}
  .media{min-height:0}
  .media picture,.media img{height:auto}
  .media img{aspect-ratio:3/2;object-fit:cover}
}

@media(max-width:760px){
  body{font-size:16px}
  .wrap,.trust-inner{width:calc(100% - 30px)}
  h1{font-size:clamp(3rem,13vw,4.5rem)}
  h2{font-size:clamp(2.45rem,11vw,3.8rem)}
  .section-heading{margin-bottom:36px}
  .hero{display:flex;flex-direction:column;align-items:stretch;min-height:0;background:var(--green-dark)}
  .hero-media{position:relative;inset:auto;z-index:0;width:100%;height:auto}
  .hero-media img{width:100%;height:auto;aspect-ratio:1919/820;object-fit:contain;object-position:center}
  .hero-shade{display:none}
  .hero-inner{min-height:0;width:100%;background:var(--green-dark)}
  .hero-copy{width:calc(100% - 30px);margin:auto;padding:43px 0 52px}
  .hero h1{margin-top:15px}
  .hero-lead{font-size:1.28rem}
  .actions{flex-direction:column}
  .btn{width:100%}
  .trust-points{grid-template-columns:1fr}
  .trust-points p{min-height:0;padding:15px 0;border-right:0;border-bottom:1px solid var(--line)}
  .trust-credentials{justify-content:space-between}
  .intro,.choice-section,.plant,.permissions,.process,.coordination,.area,.faq,.property-section,.systems,.related{padding:78px 0}
  .facts{grid-template-columns:1fr}
  .property-grid article{min-height:0;padding:30px 25px}
  .property-grid h3{margin-top:32px}
  .choice{grid-template-columns:1fr;gap:8px}
  .system-grid{grid-template-columns:1fr}
  .method-card,.photo-card,.photo-card.wide{grid-column:auto;min-height:0}
  .method-card{min-height:430px;padding:30px 25px}
  .photo-card{display:flex;flex-direction:column}
  .photo-card picture,.photo-card img{position:relative;inset:auto;width:100%;height:auto}
  .photo-card img{aspect-ratio:3/2;object-fit:contain;background:#102f28}
  .photo-card:after{display:none}
  .card-copy{position:relative;padding:28px 25px;background:var(--green-dark)}
  .media-copy{padding:54px 25px}
  .mini-grid{grid-template-columns:1fr}
  .permissions aside,.area aside{padding:31px 25px}
  .test-sequence{display:grid;grid-template-columns:1fr 1fr;gap:10px}
  .test-sequence i{display:none}
  .process-grid{grid-template-columns:1fr}
  .process-grid article{min-height:210px}
  .related-grid{grid-template-columns:1fr}
  .related-grid a{min-height:190px}
  .faq summary{font-size:1.3rem;padding-right:42px}
}

@media(max-width:390px){
  .niceic-mark span{width:112px}
  .niceic-mark img{width:112px;height:112px;transform:translateY(-32px)}
  .trust-credentials{gap:12px;min-width:0}
  .method-card h3{font-size:2.55rem}
  .media-copy{padding-inline:20px}
}

@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}