:root{
  --bedrock:#2b3440; --bedrock-deep:#1f2731; --paper:#fbfaf7; --ink:#27303b;
  --muted:#5b6573; --signal:#c0392b; --signal-dark:#a73224; --ridge:#5d7a64;
  --caution:#b08c3e; --hairline:#d4d9de;
  --slab:'Zilla Slab',Georgia,serif; --mono:'IBM Plex Mono',ui-monospace,Menlo,monospace;
  --sans:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;
}
*{box-sizing:border-box;margin:0}
html{scroll-behavior:smooth}
body{font:16px/1.65 var(--sans);color:var(--ink);background:var(--paper)}
.wrap{max-width:1080px;margin:0 auto;padding:0 22px}
a{color:inherit}
h1,h2,h3{font-family:var(--slab);line-height:1.15}
.mono{font-family:var(--mono)}
img{max-width:100%;display:block}

/* utility strip */
.util{background:var(--bedrock-deep);color:#c8d2dc;font-size:.8rem}
.util .wrap{display:flex;justify-content:space-between;align-items:center;padding-top:7px;padding-bottom:7px;gap:12px}
.util .mono{color:#fff;font-weight:600;font-size:.82rem}

/* nav */
header.site{background:var(--paper);border-bottom:1px solid var(--hairline);position:sticky;top:0;z-index:20}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;padding-top:14px;padding-bottom:14px;gap:18px}
.wordmark{font-family:var(--slab);font-weight:700;font-size:1.22rem;text-decoration:none}
.wordmark span{color:var(--signal)}
nav.main{display:flex;gap:22px;font-size:.92rem}
nav.main a{text-decoration:none;color:var(--muted);font-weight:600}
nav.main a:hover,nav.main a.on{color:var(--ink)}
.btn{display:inline-block;background:var(--signal);color:#fff;font-weight:700;text-decoration:none;padding:11px 20px;font-size:.95rem;border:none;cursor:pointer}
.btn:hover{background:var(--signal-dark)}
.btn.ghost{background:transparent;border:2px solid #fff;color:#fff}
.btn.ghost:hover{background:rgba(255,255,255,.12)}
.btn.dark{background:var(--bedrock)}
.nav-call{font-size:.88rem;padding:9px 16px}

/* hero (home) */
.hero{position:relative;color:#fff;background:
  linear-gradient(180deg,rgba(24,30,38,.78) 0%,rgba(24,30,38,.62) 55%,rgba(24,30,38,.82) 100%),
  url('images/img-01-hero-asheville-home-radon-vent.jpg') center/cover no-repeat,
  linear-gradient(165deg,#46535f 0%,#39444f 35%,#2e3842 65%,#222b34 100%)}
.hero .wrap{position:relative;padding-top:74px;padding-bottom:64px;max-width:880px}
.kicker{font:600 .78rem var(--mono);letter-spacing:.14em;text-transform:uppercase;color:#e8b8af;margin-bottom:14px}
.hero h1{font-size:clamp(2.1rem,5vw,3.15rem);font-weight:700;margin-bottom:18px}
.hero p.lead{font-size:1.06rem;line-height:1.7;color:#e3e8ee;max-width:62ch;margin-bottom:14px}
.hero p.lead strong{color:#fff}
.cta-row{display:flex;gap:14px;flex-wrap:wrap;margin-top:24px}

/* interior page header */
.pagehead{background:var(--bedrock);color:#fff;border-bottom:6px solid var(--signal)}
.pagehead .wrap{padding-top:50px;padding-bottom:42px;max-width:880px}
.pagehead h1{font-size:clamp(1.9rem,4.2vw,2.7rem);margin-bottom:14px}
.pagehead p.lead{color:#dde4eb;line-height:1.7;max-width:64ch;margin-bottom:8px}
.pagehead p.lead strong{color:#fff}
.pagehead .kicker{color:#e8b8af}
.pagehead .cta-row{margin-top:20px}

/* gauge */
.gaugeband{background:#fff;border-bottom:1px solid var(--hairline)}
.gaugeband .wrap{padding-top:26px;padding-bottom:34px}
.gauge-label-row{display:flex;justify-content:space-between;font:600 .74rem var(--mono);color:var(--muted);margin-bottom:8px}
.gauge{height:16px;position:relative;display:flex;border:1px solid #aab3bd}
.gauge .seg1{flex:0 0 50%;background:linear-gradient(180deg,#6e8a76,#5d7a64)}
.gauge .seg2{flex:0 0 25%;background:linear-gradient(180deg,#c2a05a,#b08c3e)}
.gauge .seg3{flex:1;background:linear-gradient(180deg,#cd5343,#c0392b)}
.gauge .tick{position:absolute;left:75%;top:-7px;bottom:-7px;width:3px;background:var(--ink)}
.gauge-caption{display:flex;justify-content:space-between;gap:14px;margin-top:10px;font-size:.82rem;color:var(--muted)}
.gauge-caption .action{font:700 .8rem var(--mono);color:var(--signal);white-space:nowrap}
.gauge.thin{height:8px}.gauge.thin .tick{top:-5px;bottom:-5px}
.gauge-divider{padding:18px 0 22px;border-bottom:1px solid var(--hairline);background:#fff}

/* quote strip */
.quotestrip{background:var(--paper);border-bottom:1px solid var(--hairline)}
.quotestrip .wrap{padding-top:30px;padding-bottom:26px}
.quotestrip h2{font-size:1.3rem;margin-bottom:4px}
.quotestrip .sub{color:var(--muted);font-size:.92rem;margin-bottom:16px}
.strip-form{display:grid;grid-template-columns:1fr 1fr 1fr 1.7fr auto;gap:10px}
.strip-form input{font:inherit;font-size:.92rem;padding:12px;border:1.5px solid #b7bfc8;background:#fff;width:100%}
.strip-form input:focus{outline:2px solid var(--bedrock);outline-offset:1px}
.strip-form .btn{white-space:nowrap}
.strip-micro{margin-top:12px;font-size:.85rem;color:var(--muted)}
.strip-micro .mono{font-size:.82rem;color:var(--ink)}
.hp{position:absolute;left:-9999px}

/* sections */
section.block{border-bottom:1px solid var(--hairline)}
section.block .wrap{padding-top:54px;padding-bottom:54px}
.eyebrow{font:600 .74rem var(--mono);letter-spacing:.14em;text-transform:uppercase;color:var(--signal);margin-bottom:10px}
section.block h2{font-size:clamp(1.5rem,3vw,1.95rem);margin-bottom:14px}
section.block h3{font-size:1.1rem;margin:20px 0 8px}
section.block p{max-width:68ch;color:#39434f;margin-bottom:12px}
.alt{background:#fff}

/* levels */
.levels{display:grid;grid-template-columns:repeat(3,1fr);border:1px solid var(--hairline);margin-top:26px}
.level{padding:24px 22px;background:#fff}
.level + .level{border-left:1px solid var(--hairline)}
.level .num{font:700 1.5rem var(--mono);display:block;margin-bottom:8px}
.level.ok .num{color:var(--ridge)}.level.mid .num{color:var(--caution)}.level.hot .num{color:var(--signal)}
.level h3{font-size:1.02rem;margin:0 0 8px}
.level p{font-size:.92rem;color:var(--muted)}
.level a{font-weight:700;font-size:.9rem;color:var(--signal);text-decoration:none}

/* ledger */
.ledger{border-top:2px solid var(--ink);margin-top:26px}
.lrow{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:20px 6px;border-bottom:1px solid var(--hairline);text-decoration:none;transition:background .15s}
.lrow:hover{background:#f1efe9}
.lrow .left h3{font-size:1.12rem;margin:0 0 4px}
.lrow .left p{font-size:.9rem;color:var(--muted);max-width:60ch;margin:0}
.pills{display:flex;gap:8px;flex-wrap:wrap;margin-top:8px}
.pill{font:600 .68rem var(--mono);letter-spacing:.04em;color:var(--muted);border:1px solid var(--hairline);padding:2px 9px;background:#fff}
.lrow .arrow{font-family:var(--slab);font-size:1.5rem;color:var(--signal);flex:0 0 auto}

/* two-col */
.twocol{display:grid;grid-template-columns:1.25fr 1fr;gap:36px;align-items:start}
.twocol.flip{grid-template-columns:1fr 1.25fr}
figure.ph{border:1px solid var(--hairline);background:#39434f;margin:0}
figure.ph img{width:100%;aspect-ratio:4/3;object-fit:cover}
figure.ph figcaption{font:600 .72rem var(--mono);line-height:1.5;padding:12px 14px;background:var(--bedrock-deep);color:#dfe6ec}
figure.inline-ph{margin:0 0 26px;max-width:720px}
figure.inline-ph img{aspect-ratio:16/9}
ul.tex{list-style:none;padding:0;margin-top:18px;border-top:1px solid var(--hairline);max-width:70ch}
ul.tex li{padding:13px 2px;border-bottom:1px solid var(--hairline);font-size:.95rem;color:#39434f}
ul.tex li strong{font-family:var(--slab);font-size:1rem}

/* steps */
.steps{display:grid;grid-template-columns:repeat(4,1fr);border:1px solid var(--hairline);margin-top:26px;background:#fff}
.steps.three{grid-template-columns:repeat(3,1fr)}
.step{padding:24px 20px}
.step + .step{border-left:1px solid var(--hairline)}
.step .n{font:700 .95rem var(--mono);color:var(--signal);display:block;margin-bottom:10px}
.step h3{font-size:1rem;margin:0 0 6px}
.step p{font-size:.88rem;color:var(--muted);margin:0}

/* areas */
.areas{margin-top:22px;display:flex;flex-wrap:wrap;border:1px solid var(--hairline);background:#fff}
.areas span,.areas a{padding:10px 18px;font-size:.9rem;border-right:1px solid var(--hairline);border-bottom:1px solid var(--hairline);text-decoration:none}
.areas a:hover{background:#f1efe9}

/* faqs */
details{border-bottom:1px solid var(--hairline)}
details:first-of-type{border-top:2px solid var(--ink)}
summary{cursor:pointer;font-family:var(--slab);font-weight:600;font-size:1.08rem;padding:18px 4px;list-style:none;display:flex;justify-content:space-between;gap:14px}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";font-family:var(--mono);color:var(--signal);font-weight:600}
details[open] summary::after{content:"–"}
details .a{padding:0 4px 20px;color:#39434f;max-width:70ch;font-size:.95rem}
details .a p{margin-bottom:10px}

/* finale */
.finale{background:var(--bedrock);color:#fff;border-top:6px solid var(--signal)}
.finale .wrap{padding-top:56px;padding-bottom:56px}
.finale h2{font-size:clamp(1.6rem,3.4vw,2.2rem);max-width:26ch;margin-bottom:12px}
.finale p{color:#cfd7df;max-width:60ch;margin-bottom:24px}

/* contact / full form */
.bigform{max-width:640px;display:grid;gap:12px;margin-top:24px}
.bigform label{font-weight:600;font-size:.88rem}
.bigform input,.bigform textarea{font:inherit;font-size:.95rem;padding:12px;border:1.5px solid #b7bfc8;background:#fff;width:100%}
.bigform textarea{min-height:110px}
.bigform .note{font-size:.82rem;color:var(--muted)}

/* footer */
footer{background:var(--bedrock-deep);color:#aeb9c4;font-size:.88rem}
footer .wrap{padding-top:44px;padding-bottom:90px;display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:30px}
footer h4{color:#fff;font-family:var(--slab);font-size:.98rem;margin-bottom:12px}
footer a{display:block;color:#aeb9c4;text-decoration:none;padding:3px 0}
footer a:hover{color:#fff}
footer p{margin-bottom:8px}

/* sticky call bar */
.callbar{display:none;position:fixed;left:0;right:0;bottom:0;z-index:50;background:var(--signal);color:#fff;text-align:center;font-weight:800;padding:15px;text-decoration:none;font-size:1.02rem}

.navtoggle{display:none}
.hamburger{display:none;flex-direction:column;justify-content:center;gap:5px;width:42px;height:42px;padding:9px;border:1px solid var(--hairline);background:#fff;cursor:pointer}
.hamburger span{display:block;height:2.5px;background:var(--ink)}
.navtoggle:checked ~ .hamburger span{background:var(--signal)}
nav.main .navphone{display:none}

@media (max-width:880px){
  header.site .wrap{position:relative}
  .hamburger{display:flex}
  nav.main{display:none;position:absolute;top:100%;left:0;right:0;background:var(--paper);border-bottom:2px solid var(--signal);box-shadow:0 14px 24px rgba(31,39,49,.18);flex-direction:column;gap:0;padding:6px 22px 14px;z-index:30}
  nav.main a{padding:13px 2px;border-bottom:1px solid var(--hairline);font-size:1rem;color:var(--ink)}
  nav.main .navphone{display:block;color:var(--signal);border-bottom:none;font-weight:800}
  .navtoggle:checked ~ nav.main{display:flex}
  .strip-form{grid-template-columns:1fr 1fr}
  .strip-form input[name=test_result]{grid-column:1/-1}
  .strip-form .btn{grid-column:1/-1}
  .levels,.steps,.steps.three{grid-template-columns:1fr}
  .level + .level,.step + .step{border-left:none;border-top:1px solid var(--hairline)}
  .twocol,.twocol.flip{grid-template-columns:1fr}
  footer .wrap{grid-template-columns:1fr 1fr}
  .callbar{display:block}
  .nav-call{display:none}
  .hero .wrap{padding-top:48px;padding-bottom:46px}
  body{padding-bottom:54px}
}