/* Design tokens. One accent (steel blue), one radius system (sharp), one theme per visitor (light or dark by system). */
:root{
 --bg:#fafbfc;--surface:#f0f2f6;--ink:#0d1b33;--text:#2b3548;--muted:#586377;--line:#dce1e9;
 --accent:#2a6f97;--btn-bg:#0d1b33;--btn-fg:#f4f6f9;
 --navy:#0d1b33;--navy-2:#14284a;--on-navy:#f1f4f9;--on-navy-muted:#aab6cb;--accent-on-navy:#8fc0e3;
 --font:"Pretendard Variable",Pretendard,-apple-system,"Apple SD Gothic Neo","Malgun Gothic",sans-serif;
 --ease:cubic-bezier(.16,1,.3,1);
 color-scheme:light dark;
}
@media (prefers-color-scheme:dark){:root{
 --bg:#0a1120;--surface:#111b30;--ink:#eef1f6;--text:#c3cad8;--muted:#8f9aae;--line:#223049;
 --accent:#7db3d8;--btn-bg:#e8edf5;--btn-fg:#0d1b33;--navy:#0f1d38;--navy-2:#16294a;
}}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--font);color:var(--text);background:var(--bg);line-height:1.8;font-size:16px;word-break:keep-all;-webkit-font-smoothing:antialiased}
a{color:var(--ink);text-underline-offset:3px}
img{display:block;max-width:100%}
.wrap{max-width:1240px;margin:0 auto;padding:0 32px}

/* header */
header.site{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--bg) 92%,transparent);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;height:72px}
.logo{font-weight:700;font-size:19px;letter-spacing:-.03em;color:var(--ink);text-decoration:none}
nav.gnb{display:flex;align-items:center;gap:30px}
nav.gnb a{text-decoration:none;color:var(--text);font-size:15px;font-weight:500;white-space:nowrap;transition:color .2s}
nav.gnb a:hover{color:var(--accent)}
nav.gnb a.nav-cta{background:var(--btn-bg);color:var(--btn-fg);padding:10px 20px;font-weight:600}
nav.gnb a.nav-cta:hover{color:var(--btn-fg);opacity:.88}
.nt,.burger{display:none}

/* buttons */
.btn{display:inline-block;background:var(--btn-bg);color:var(--btn-fg);padding:15px 30px;text-decoration:none;font-weight:600;font-size:15px;border:1px solid var(--btn-bg);white-space:nowrap;transition:transform .2s var(--ease),opacity .2s}
.btn:hover{opacity:.88}
.btn:active{transform:translateY(1px)}
.btn.light{background:var(--on-navy);color:var(--navy);border-color:var(--on-navy)}
.btn.line{background:transparent;color:var(--on-navy);border-color:rgba(241,244,249,.45)}
.btn.line:hover{background:rgba(241,244,249,.1);opacity:1}
.link{font-weight:600;text-decoration:none;color:var(--accent);font-size:15px}
.link:hover{text-decoration:underline}

/* hero */
.hero{background:var(--navy);color:var(--on-navy);position:relative;overflow:hidden}
.hero .wrap{display:grid;grid-template-columns:1.05fr .95fr;align-items:center;gap:0;min-height:min(84dvh,700px);padding:0 32px}
.hero-copy{padding:72px 56px 72px 0;position:relative;z-index:1}
.hero .kicker{color:var(--accent-on-navy);font-size:14px;font-weight:600;letter-spacing:.02em;margin:0 0 20px}
.hero h1{font-size:clamp(34px,4.6vw,60px);font-weight:700;line-height:1.22;letter-spacing:-.04em;margin:0 0 24px;color:#fff}
.hero p.lead{color:var(--on-navy-muted);font-size:18px;max-width:30em;margin:0 0 40px}
.hero .actions{display:flex;gap:12px;flex-wrap:wrap}
.hero-img{position:absolute;top:0;right:0;bottom:0;width:50%;background:url(/images/hero.jpg) center/cover}
.hero-img:after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,var(--navy) 0%,rgba(13,27,51,.55) 38%,rgba(13,27,51,.25) 100%)}

/* sections */
section{padding:112px 0}
section.tint{background:var(--surface)}
.head{max-width:640px;margin:0 0 56px}
.head h2,.split h2{font-size:clamp(28px,3.4vw,40px);line-height:1.3;letter-spacing:-.035em;color:var(--ink);margin:0 0 16px;font-weight:700}
.head p{color:var(--muted);margin:0;font-size:17px}

/* bento: 4 items, 4 cells */
.bento{display:grid;grid-template-columns:repeat(12,1fr);gap:16px}
.cell{padding:40px;display:flex;flex-direction:column;justify-content:flex-end;min-height:290px;position:relative;overflow:hidden;background:var(--surface);color:var(--text)}
.cell h3{font-size:24px;letter-spacing:-.03em;margin:0 0 10px;color:var(--ink);font-weight:700}
.cell p{margin:0 0 22px;max-width:28em;color:var(--muted)}
.cell .link{align-self:flex-start}
.cell.a{grid-column:span 7;background:var(--navy);color:var(--on-navy-muted);min-height:340px}
.cell.a h3{color:#fff;font-size:30px}
.cell.a p{color:var(--on-navy-muted)}
.cell.a .link,.cell.c .link{color:var(--accent-on-navy)}
.cell.b{grid-column:span 5}
.cell.c{grid-column:span 5;color:var(--on-navy-muted);background:var(--navy)}
.cell.c:before{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(13,27,51,.35),rgba(13,27,51,.94)),url(/images/towers.jpg) center/cover;transition:transform .8s var(--ease)}
.cell.c:hover:before{transform:scale(1.04)}
.cell.c>*{position:relative}
.cell.c h3{color:#fff}
.cell.c p{color:var(--on-navy-muted)}
.cell.d{grid-column:span 7;background:color-mix(in srgb,var(--accent) 14%,var(--surface))}
section.tint .cell.b{background:var(--bg)}

/* about */
.split{display:grid;grid-template-columns:5fr 7fr;gap:80px;align-items:start}
.split p{color:var(--muted);font-size:17px;margin:0 0 28px;max-width:30em}
.facts{margin:0;padding:0;list-style:none;border-top:2px solid var(--ink)}
.facts li{padding:20px 0;border-bottom:1px solid var(--line);display:grid;grid-template-columns:150px 1fr;gap:20px}
.facts b{color:var(--ink);font-weight:600}
.facts span{color:var(--text)}

/* research list */
.rows{border-top:2px solid var(--ink)}
.rows a{display:grid;grid-template-columns:1fr auto;gap:24px;align-items:center;padding:30px 4px;border-bottom:1px solid var(--line);text-decoration:none;transition:padding .35s var(--ease),background .25s}
.rows a:hover{padding-left:20px;background:var(--surface)}
.rows h3{margin:0 0 6px;font-size:21px;letter-spacing:-.03em;color:var(--ink);font-weight:600}
.rows p{margin:0;color:var(--muted);font-size:15.5px}
.rows .go{color:var(--accent);font-size:22px}
.sticky{position:sticky;top:112px}

/* faq */
.faq{max-width:780px}
details{border-bottom:1px solid var(--line);padding:22px 0}
details:first-of-type{border-top:2px solid var(--ink)}
summary{cursor:pointer;font-weight:600;color:var(--ink);font-size:18px;letter-spacing:-.02em;list-style:none;display:flex;justify-content:space-between;gap:20px}
summary::-webkit-details-marker{display:none}
summary:after{content:"+";color:var(--accent);font-size:22px;line-height:1.2}
details[open] summary:after{content:"-"}
details p{margin:14px 0 0;color:var(--muted);max-width:42em}

/* closing band */
.band{background:var(--navy);color:var(--on-navy);padding:104px 0}
.band .wrap{display:flex;align-items:center;justify-content:space-between;gap:48px;flex-wrap:wrap}
.band h2{font-size:clamp(28px,3.6vw,42px);letter-spacing:-.035em;margin:0 0 12px;color:#fff;font-weight:700;line-height:1.3}
.band p{color:var(--on-navy-muted);margin:0}

/* subpages */
.page-hero{background:var(--navy);color:var(--on-navy);padding:72px 0 64px}
.page-hero h1{font-size:clamp(30px,4vw,46px);font-weight:700;letter-spacing:-.04em;line-height:1.3;margin:0;color:#fff}
.page-hero .crumb{color:var(--on-navy-muted);font-size:14px;margin:0 0 18px}
.page-hero .crumb a{color:var(--on-navy-muted)}
article{max-width:780px;margin:0 auto;padding:72px 32px 112px;font-size:17px}
article h2{color:var(--ink);font-size:26px;letter-spacing:-.03em;margin:56px 0 16px;font-weight:700;line-height:1.4}
article h3{color:var(--ink);font-size:20px;letter-spacing:-.02em;margin:32px 0 8px}
article a{color:var(--accent)}
article .btn{color:var(--btn-fg)}
.meta{color:var(--muted);font-size:14px;margin:0 0 28px}
.toc{background:var(--surface);border-top:2px solid var(--ink);padding:20px 28px;margin:0 0 20px}
.toc ol{margin:8px 0 0;padding-left:20px}
blockquote{margin:26px 0;padding:18px 24px;border-left:3px solid var(--accent);background:var(--surface);color:var(--text)}
table{border-collapse:collapse;width:100%;margin:22px 0;font-size:15.5px;border-top:2px solid var(--ink)}
th,td{border-bottom:1px solid var(--line);padding:14px 16px;text-align:left;vertical-align:top}
th{background:var(--surface);color:var(--ink);font-weight:600}
article details:first-of-type{margin-top:8px}
.notice{font-size:14px;color:var(--muted);border-top:1px solid var(--line);margin-top:56px;padding-top:20px}
.mail{font-size:clamp(24px,4vw,34px);font-weight:700;letter-spacing:-.03em;margin:28px 0}
.mail a{color:var(--ink)}

/* footer */
footer{background:var(--navy);color:var(--on-navy-muted);padding:72px 0 56px;font-size:14.5px}
footer .wrap{display:grid;grid-template-columns:1.4fr 1fr;gap:56px}
footer strong{color:#fff;font-size:18px;letter-spacing:-.02em;display:block;margin-bottom:14px}
footer p{margin:0 0 4px}
footer a{color:var(--on-navy);text-decoration:none}
footer a:hover{text-decoration:underline}
footer .links{display:grid;grid-template-columns:1fr 1fr;gap:10px 24px;align-content:start}
footer .legal{grid-column:1/-1;border-top:1px solid rgba(241,244,249,.14);padding-top:24px;font-size:13px}

/* motion: only hierarchy reveals; honors reduced motion */
@media (prefers-reduced-motion:no-preference){
 .hero-copy>*{animation:rise .9s var(--ease) both}
 .hero-copy>*:nth-child(2){animation-delay:.08s}.hero-copy>*:nth-child(3){animation-delay:.16s}.hero-copy>*:nth-child(4){animation-delay:.24s}
 .js .reveal{opacity:0;transform:translateY(22px);transition:opacity .8s var(--ease),transform .8s var(--ease)}
 .js .reveal.in{opacity:1;transform:none}
 .js .reveal.d1{transition-delay:.08s}.js .reveal.d2{transition-delay:.16s}.js .reveal.d3{transition-delay:.24s}
}
@keyframes rise{from{opacity:0;transform:translateY(22px)}to{opacity:1;transform:none}}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}

@media(max-width:960px){
 .wrap{padding:0 20px}
 header.site .wrap{height:64px}
 .burger{display:block;cursor:pointer;font-weight:600;color:var(--ink);padding:8px 0}
 nav.gnb{position:absolute;top:64px;left:0;right:0;background:var(--bg);border-bottom:1px solid var(--line);flex-direction:column;align-items:stretch;gap:0;padding:8px 20px 20px;display:none}
 .nt:checked~nav.gnb{display:flex}
 nav.gnb a{padding:14px 0;border-bottom:1px solid var(--line)}
 nav.gnb a.nav-cta{text-align:center;margin-top:14px;border:0}
 .hero .wrap{grid-template-columns:1fr;min-height:0;padding:0 20px}
 .hero-copy{padding:56px 0 360px}
 .hero-img{top:auto;width:100%;height:320px}
 .hero-img:after{background:linear-gradient(180deg,var(--navy) 0%,rgba(13,27,51,.3) 100%)}
 section{padding:72px 0}
 .bento{grid-template-columns:1fr}
 .cell.a,.cell.b,.cell.c,.cell.d{grid-column:auto;min-height:240px;padding:28px}
 .split{grid-template-columns:1fr;gap:40px}
 .facts li{grid-template-columns:1fr;gap:4px}
 .sticky{position:static}
 .band{padding:72px 0}
 footer .wrap{grid-template-columns:1fr;gap:32px}
 article{padding:48px 20px 80px}
}