/* THERMAL AIR LAB — airheater.korsolarheat.com */
:root{--bg:#F7F5F0;--bg2:#EEEAE0;--card:#FCFBF8;--ink:#20282B;--ink2:#3B464A;--mut:#566266;--line:rgba(32,40,43,.16);--or:#F28C38;--or-ink:#A04D09;--cool:#9EB6B7;--cool-d:#3F6264;--deep:#161C1E;--w:1200px;--gut:clamp(20px,4vw,40px);--r:6px;
--f:"Pretendard Variable",Pretendard,"Noto Sans KR","Apple SD Gothic Neo","Malgun Gothic",system-ui,-apple-system,"Segoe UI",sans-serif}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}
body{margin:0;background:var(--bg);color:var(--ink);font:400 17px/1.85 var(--f);letter-spacing:-.012em;word-break:keep-all;overflow-wrap:anywhere;-webkit-font-smoothing:antialiased}
img,svg{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration-thickness:1px;text-underline-offset:3px}
a:focus-visible,summary:focus-visible,button:focus-visible{outline:3px solid var(--or);outline-offset:3px}
h1,h2,h3{font-family:var(--f);line-height:1.28;margin:0;letter-spacing:-.025em}
p{margin:0 0 1.1em}
ul,ol{margin:0 0 1.2em;padding-left:1.3em}
li{margin:.35em 0}
.wrap{width:100%;max-width:calc(var(--w) + var(--gut)*2);margin:0 auto;padding:0 var(--gut)}
.vh{position:absolute!important;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.skip{position:absolute;left:-999px;top:8px;background:var(--or);color:var(--ink);padding:10px 16px;z-index:100;font-weight:700}
.skip:focus{left:8px}

/* header */
.hd{background:var(--ink);color:#fff;position:sticky;top:0;z-index:50;border-bottom:1px solid rgba(255,255,255,.08)}
.hd .wrap{display:flex;align-items:center;gap:20px;min-height:68px}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none;color:#fff;flex:0 0 auto}
.logo svg{width:34px;height:34px}
.logo b{display:block;font:700 15px/1.1 var(--f);letter-spacing:.06em}
.logo small{display:block;font:500 10.5px/1.3 var(--f);letter-spacing:.14em;color:var(--cool);text-transform:uppercase}
.nav{display:none;gap:clamp(12px,1.6vw,26px);margin-left:auto;font-size:14.5px;font-weight:500}
.nav a{color:#E6E2D8;text-decoration:none;padding:10px 2px;border-bottom:2px solid transparent}
.nav a:hover,.nav a[aria-current]{color:#fff;border-bottom-color:var(--or)}
.btn{display:inline-flex;flex-direction:column;align-items:center;justify-content:center;gap:1px;min-height:48px;padding:8px 22px;border-radius:999px;background:var(--or);color:var(--ink);font:700 15px/1.2 var(--f);text-decoration:none;border:0;cursor:pointer;transition:background .2s,transform .2s;text-align:center}
.btn:hover{background:#FFA050}
.btn small{font:600 11px/1.1 var(--f);letter-spacing:.04em;opacity:.85;white-space:nowrap}
.btn span{white-space:nowrap}
.btn--row{flex-direction:row;gap:10px;padding:12px 28px;font-size:17px}
.btn--ghost{background:transparent;color:#fff;border:1.5px solid rgba(255,255,255,.5)}
.btn--ghost:hover{background:rgba(255,255,255,.1)}
.btn--line{background:transparent;color:var(--ink);border:1.5px solid var(--ink)}
.btn--line:hover{background:var(--ink);color:#fff}
.hd .btn{margin-left:auto;padding:6px 16px;min-height:46px}
.menu{position:relative}
.menu summary{list-style:none;cursor:pointer;width:46px;height:46px;display:grid;place-items:center;border:1px solid rgba(255,255,255,.28);border-radius:8px}
.menu summary::-webkit-details-marker{display:none}
.menu summary span,.menu summary span::before,.menu summary span::after{display:block;width:20px;height:2px;background:#fff;content:"";position:relative}
.menu summary span::before{position:absolute;top:-6px}
.menu summary span::after{position:absolute;top:6px}
.menu nav{position:absolute;right:0;top:56px;width:min(300px,86vw);background:var(--ink);border:1px solid rgba(255,255,255,.14);border-radius:10px;padding:10px;display:grid}
.menu nav a{padding:13px 14px;text-decoration:none;color:#fff;border-radius:6px;font-weight:500}
.menu nav a:hover{background:rgba(255,255,255,.08)}
@media(min-width:1040px){.nav{display:flex}.menu{display:none}.hd .btn{margin-left:8px}}

/* hero (home) */
.hero{position:relative;background:var(--ink);color:#fff;isolation:isolate;overflow:hidden}
.hero picture,.hero img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-2}
.hero::before{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,rgba(22,28,30,.92) 0%,rgba(22,28,30,.7) 42%,rgba(22,28,30,.12) 100%),linear-gradient(0deg,rgba(22,28,30,.7),rgba(22,28,30,0) 40%)}
.hero .wrap{min-height:clamp(560px,82vh,760px);display:flex;flex-direction:column;justify-content:center;padding-top:72px;padding-bottom:110px}
.hero .pre{font:600 clamp(24px,3.6vw,42px)/1.3 var(--f);margin:0 0 6px;letter-spacing:-.03em}
.hero h1{font-size:clamp(52px,9.2vw,104px);font-weight:800;color:var(--or);letter-spacing:-.045em;line-height:1.05;margin:0 0 26px}
.hero .lead{max-width:560px;font-size:clamp(16px,1.7vw,19px);color:#EDE9DF;line-height:1.85}
.hero .acts{margin-top:30px}
.hero .meta{position:absolute;left:0;right:0;bottom:22px;font:500 11.5px/1.6 var(--f);letter-spacing:.14em;text-transform:uppercase;color:#CBD5D5}
.hero .meta .wrap{min-height:0;padding-top:0;padding-bottom:0;display:flex;flex-wrap:wrap;gap:6px 28px;justify-content:space-between}
.hero .meta span+span{text-transform:none;letter-spacing:.02em;font-size:12.5px;color:#B9C6C6}

/* sub hero */
.phero{background:var(--ink);color:#fff;position:relative;overflow:hidden;padding:clamp(40px,6vw,76px) 0 clamp(48px,6vw,80px)}
.phero::after{content:"";position:absolute;right:-60px;top:0;bottom:0;width:min(56%,640px);background:url("/assets/air-lines.svg") right center/cover no-repeat;opacity:.55;pointer-events:none}
.phero .wrap{position:relative;z-index:1}
.crumb{font-size:13.5px;color:var(--cool);margin:0 0 28px;display:flex;flex-wrap:wrap;gap:4px 10px;padding:0;list-style:none}
.crumb li{margin:0}
.crumb li+li::before{content:"/";margin-right:10px;opacity:.5}
.crumb a{text-decoration:none;color:#D5DEDE}
.crumb a:hover{color:#fff;text-decoration:underline}
.eyebrow{display:flex;align-items:center;gap:12px;font:700 12px/1 var(--f);letter-spacing:.2em;text-transform:uppercase;color:var(--or-ink);margin:0 0 16px}
.eyebrow::before{content:"";width:34px;height:2px;background:currentColor}
.phero .eyebrow{color:var(--or)}
.phero h1{font-size:clamp(36px,6vw,64px);font-weight:800;letter-spacing:-.04em;margin:0 0 22px;max-width:14em}
.phero .lead{max-width:760px;font-size:clamp(16.5px,1.8vw,20px);color:#E8E4DA;margin:0 0 28px}

/* sections */
.sec{padding:clamp(64px,9vw,128px) 0}
.sec--alt{background:var(--bg2)}
.sec--dark{background:var(--ink);color:#fff}
.sec h2{font-size:clamp(26px,3.5vw,42px);font-weight:700;margin:0 0 .5em}
.sec .intro{max-width:720px;color:var(--ink2);font-size:18px;margin-bottom:2.2em}
.sec--dark .intro{color:#D4DCDC}
.sx{display:grid;gap:18px 56px;grid-template-columns:minmax(0,1fr)}
.sx>h2{margin:0;font-size:clamp(24px,3vw,34px)}
@media(min-width:960px){.sx{grid-template-columns:minmax(0,320px) minmax(0,1fr)}.sx>h2{position:sticky;top:96px;align-self:start}}
.prose{max-width:780px}
.prose ul,.prose ol{padding-left:1.25em}
.prose li::marker{color:var(--or-ink);font-weight:700}
.sx+.sx{margin-top:clamp(48px,6vw,80px);padding-top:clamp(40px,5vw,64px);border-top:1px solid var(--line)}
.blk{margin-top:clamp(56px,7vw,96px)}
.blk+.sx,.blk+.blk{margin-top:clamp(56px,7vw,96px)}
.sx+.blk{padding-top:0}
.blk h2{font-size:clamp(24px,3vw,34px);margin-bottom:.6em}
.note{font-size:14.5px;color:var(--mut);max-width:780px;margin:0 0 22px}

/* cards */
.cards{display:grid;gap:20px;grid-template-columns:repeat(3,minmax(0,1fr))}
.cards--4{grid-template-columns:repeat(4,minmax(0,1fr))}
ul.cards{list-style:none;margin:0;padding:0}
.cards>li{margin:0;display:flex}.cards>li>.card{width:100%}
.card{display:flex;flex-direction:column;background:var(--card);border:1px solid var(--line);border-radius:var(--r);text-decoration:none;overflow:hidden;transition:border-color .2s,transform .2s}
.card:hover{border-color:var(--ink);transform:translateY(-2px)}
.card img{width:100%;aspect-ratio:4/3;object-fit:cover;background:var(--bg2)}
.card .bd{padding:18px 20px 22px;display:flex;flex-direction:column;gap:6px;flex:1}
.card .tag{font:700 11px/1 var(--f);letter-spacing:.16em;text-transform:uppercase;color:var(--or-ink)}
.card strong{font-size:19px;letter-spacing:-.025em;line-height:1.3}
.card p{font-size:14.5px;color:var(--mut);line-height:1.65;margin:0}
.card .go{margin-top:auto;padding-top:10px;font-size:13.5px;font-weight:700;color:var(--ink)}
.card--t .bd{padding:22px}
.card--car strong{font-size:18px}
@media(max-width:1020px){.cards--4{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:720px){.cards,.cards--car{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.card .bd{padding:12px 12px 16px}.card strong{font-size:15.5px}.card p{font-size:13px}.card--t .bd{padding:16px}.cards--1m{grid-template-columns:minmax(0,1fr)}}
@media(max-width:380px){.cards--1m,.cards--4{grid-template-columns:minmax(0,1fr)}}

/* photos */
.ph{display:grid;gap:12px;grid-template-columns:repeat(4,minmax(0,1fr));margin:0;padding:0;list-style:none}
.ph--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.ph figure{margin:0}
.ph img{width:100%;aspect-ratio:1/1;object-fit:cover;border-radius:var(--r);background:var(--bg2);border:1px solid var(--line)}
.ph--2 img{aspect-ratio:3/2}
.ph figcaption{font-size:12.5px;line-height:1.5;color:var(--mut);margin-top:8px}
@media(max-width:720px){.ph{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}}

/* diagram */
.dg{background:var(--ink);color:#fff;border-radius:var(--r);padding:clamp(14px,3vw,34px)}
.dg svg{width:100%;height:auto}
.dg .cap{font:600 11.5px/1.4 var(--f);letter-spacing:.14em;text-transform:uppercase;color:var(--cool);margin:0 0 14px}
.lg{display:grid;gap:14px 28px;grid-template-columns:repeat(4,minmax(0,1fr));list-style:none;margin:26px 0 0;padding:0;counter-reset:n}
.lg li{margin:0;font-size:14.5px;line-height:1.65;color:#D8E0E0;counter-increment:n}
.lg li b{display:block;color:#fff;font-size:15.5px;margin-bottom:3px}
.lg li b::before{content:counter(n);display:inline-grid;place-items:center;width:24px;height:24px;border-radius:50%;background:var(--or);color:var(--ink);font-size:13px;font-weight:800;margin-right:8px}
@media(max-width:900px){.lg{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:520px){.lg{grid-template-columns:minmax(0,1fr)}}
.dgnote{font-size:13px;color:#A9B8B8;margin:18px 0 0}

/* table */
.tw{margin:0}
.tbl{width:100%;border-collapse:collapse;background:var(--card);border:1px solid var(--line);font-size:15.5px;line-height:1.65}
.tbl caption{caption-side:top;text-align:left;font-size:14.5px;color:var(--mut);padding:0 0 12px}
.tbl th,.tbl td{padding:16px 18px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
.tbl thead th{background:var(--ink);color:#fff;font-weight:700;font-size:14px;letter-spacing:.02em}
.tbl tbody th,.tbl td:first-child{font-weight:700;background:rgba(158,182,183,.18);width:22%}
@media(max-width:720px){
 .tbl,.tbl tbody,.tbl tr,.tbl td,.tbl th{display:block;width:100%}
 .tbl{border:0;background:transparent}
 .tbl thead{position:absolute;left:-9999px;top:auto;width:1px;height:1px;overflow:hidden}
 .tbl tr{border:1px solid var(--line);border-radius:var(--r);margin:0 0 14px;background:var(--card);overflow:hidden}
 .tbl td{border:0;border-top:1px solid var(--line);padding:12px 16px}
 .tbl td:first-child{background:var(--ink);color:#fff;border:0;width:100%}
 .tbl td+td::before{content:attr(data-label);display:block;font:700 11.5px/1.3 var(--f);letter-spacing:.08em;color:var(--or-ink);margin-bottom:3px}
}

/* steps */
.steps{list-style:none;margin:0;padding:0;display:grid;gap:0;counter-reset:s;grid-template-columns:repeat(3,minmax(0,1fr));border-top:1px solid var(--line);border-left:1px solid var(--line)}
.steps li{margin:0;padding:24px 22px 26px;border-right:1px solid var(--line);border-bottom:1px solid var(--line);counter-increment:s;background:var(--card)}
.steps li::before{content:"0" counter(s);display:block;font:800 13px/1 var(--f);letter-spacing:.14em;color:var(--or-ink);margin-bottom:12px}
.steps b{display:block;font-size:18px;margin-bottom:6px;letter-spacing:-.025em}
.steps span{display:block;font-size:14.5px;color:var(--mut);line-height:1.65}
@media(max-width:860px){.steps{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:520px){.steps{grid-template-columns:minmax(0,1fr)}}

/* faq */
.faq{max-width:900px}
.faq div{border-top:1px solid var(--line);padding:26px 0 8px}
.faq div:last-child{border-bottom:1px solid var(--line)}
.faq h3{font-size:clamp(17.5px,2vw,21px);font-weight:700;display:flex;gap:12px;margin:0 0 10px}
.faq h3::before{content:"Q";flex:0 0 auto;font:800 15px/1 var(--f);color:var(--or-ink);margin-top:.45em;letter-spacing:.04em}
.faq p{margin:0 0 18px;padding-left:28px;color:var(--ink2)}

/* cta */
.cta{background:var(--ink);color:#fff;padding:clamp(56px,8vw,104px) 0;position:relative;overflow:hidden}
.cta::after{content:"";position:absolute;inset:0;background:url("/assets/air-lines.svg") right center/cover no-repeat;opacity:.35;pointer-events:none}
.cta .wrap{position:relative;z-index:1;display:flex;flex-wrap:wrap;gap:24px 48px;align-items:center;justify-content:space-between}
.cta h2{font-size:clamp(26px,3.6vw,42px);font-weight:700;max-width:18em}
.cta p{color:#D4DCDC;margin:12px 0 0;max-width:560px}

/* consultation */
.contact{display:grid;gap:16px;grid-template-columns:repeat(2,minmax(0,1fr));max-width:760px;margin-top:8px}
.cbtn{display:flex;align-items:center;gap:16px;min-height:76px;padding:16px 24px;border-radius:var(--r);text-decoration:none;font-weight:700}
.cbtn small{display:block;font:600 12px/1.3 var(--f);letter-spacing:.1em;opacity:.8}
.cbtn b{display:block;font-size:clamp(20px,2.6vw,26px);line-height:1.2;letter-spacing:-.02em}
.cbtn--tel{background:var(--or);color:var(--ink)}
.cbtn--sms{background:transparent;color:#fff;border:1.5px solid rgba(255,255,255,.6)}
.cbtn:hover{filter:brightness(1.07)}
.cbtn svg{width:30px;height:30px;flex:0 0 auto}
@media(max-width:620px){.contact{grid-template-columns:minmax(0,1fr)}}
.chk{list-style:none;padding:0;margin:0 0 1.4em}
.chk li{position:relative;padding:14px 0 14px 34px;border-bottom:1px solid var(--line);margin:0}
.chk li::before{content:"";position:absolute;left:2px;top:22px;width:14px;height:14px;border:2px solid var(--or-ink);border-radius:3px}
.chk b{display:block}

/* footer */
.ft{background:var(--deep);color:#B8C3C4;font-size:13.5px;line-height:1.7;padding:30px 0 34px}
.ft .wrap{display:flex;flex-wrap:wrap;gap:8px 0;align-items:center}
.ft .brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:700;margin-right:28px}
.ft .brand svg{width:28px;height:28px}
.ft ul{display:flex;flex-wrap:wrap;list-style:none;margin:0;padding:0;flex:1 1 560px}
.ft li{margin:0;padding:0 14px;border-left:1px solid rgba(255,255,255,.16)}
.ft li:first-child{border-left:0;padding-left:0}
.ft li b{color:#E9EEEE;font-weight:600;margin-right:6px}
.ft a{color:#DDE6E6}
@media(max-width:620px){.ft li{flex:1 1 100%;border-left:0;padding:0}.ft ul{gap:2px}}

/* hub */
.grp+.grp{margin-top:clamp(48px,6vw,88px)}
.grp>h2{display:flex;align-items:baseline;gap:14px;flex-wrap:wrap;font-size:clamp(22px,2.6vw,30px);margin-bottom:22px;padding-bottom:14px;border-bottom:2px solid var(--ink)}
.grp>h2 small{font:700 12px/1 var(--f);letter-spacing:.2em;color:var(--or-ink);text-transform:uppercase}
.hub .card--t.main{border-color:var(--ink);background:#fff}
.hubnote{color:var(--mut)}

.err{padding:clamp(72px,12vw,160px) 0;text-align:left}
.err h1{font-size:clamp(34px,6vw,64px);margin-bottom:18px}

@media(max-width:560px){
 .hd .wrap{gap:10px;min-height:64px}
 .logo small{display:none}.logo b{font-size:13px;letter-spacing:.04em}.logo svg{width:30px;height:30px}
 .hd .btn{padding:6px 14px;min-height:44px;font-size:13.5px}.hd .btn small{font-size:11px;letter-spacing:.02em}
 .menu summary{width:44px;height:44px}
 .hero::before{background:linear-gradient(180deg,rgba(22,28,30,.78),rgba(22,28,30,.66) 50%,rgba(22,28,30,.82))}
 .hero .wrap{padding-top:56px;padding-bottom:96px}
 .btn--row{padding:12px 22px;font-size:16px}
}
@media(max-width:360px){.logo b{display:none}.hd .btn{padding:6px 12px}}