/* ==========================================================================
   ㈜엘프테크 랜딩 v2
   Aesthetic: precision-instrument / dark technical. Native CSS, no framework.
   Dials: DESIGN_VARIANCE 7 · MOTION_INTENSITY 5 · VISUAL_DENSITY 4
   Theme lock: dark, whole page. Accent lock: brand cyan, whole page.
   Radius rule: surfaces 14px · media 10px · interactive full-pill. Applied everywhere.
   ========================================================================== */

:root{
  /* neutrals: one cool family, no warm/cool mixing */
  --bg:#070E12;
  --bg-2:#0A151B;
  --surf:#0E1D25;
  --surf-2:#132A34;
  --line:rgba(255,255,255,.09);
  --line-2:rgba(255,255,255,.16);

  --ink:#E9F1F4;
  --ink-2:#B4C7CF;
  --mut:#7E96A1;

  /* single accent, locked (brand) */
  --ac:#30A8C0;
  --ac-hi:#6FDCEF;
  --ac-dim:rgba(48,168,192,.14);

  --sans:'IBM Plex Sans KR','IBM Plex Sans',system-ui,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,monospace;

  --r-surf:14px;
  --r-media:10px;
  --r-pill:999px;

  --pad:clamp(20px,4vw,32px);
  --wrap:1200px;
  --sec:clamp(72px,8vw,112px);
}

*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:88px;-webkit-text-size-adjust:100%}

body{
  background:var(--bg);
  color:var(--ink);
  font-family:var(--sans);
  font-weight:400;
  line-height:1.7;
  letter-spacing:-.005em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}

a{color:inherit;text-decoration:none}
img,picture{display:block;max-width:100%}
picture img{height:auto}
ul{list-style:none}

.wrap{max-width:var(--wrap);margin:0 auto;padding-inline:var(--pad)}
.sec{padding-block:var(--sec)}

/* ---------- type scale ---------- */
h1,h2,h3,h4{line-height:1.15;letter-spacing:-.03em;font-weight:600;color:#fff}
h1{font-size:clamp(38px,5.4vw,68px);font-weight:700;letter-spacing:-.04em}
h2{font-size:clamp(28px,3.6vw,46px)}
h3{font-size:clamp(20px,2.1vw,27px)}
h4{font-size:clamp(16px,1.4vw,19px);letter-spacing:-.02em}

.lead{font-size:clamp(15px,1.35vw,18px);color:var(--ink-2);max-width:62ch}
.body{font-size:15.5px;color:var(--mut);max-width:65ch}

/* eyebrow: budget is ceil(sections/3). Used exactly 3 times on this page. */
.eyebrow{
  font-family:var(--mono);font-size:11.5px;font-weight:500;
  letter-spacing:.2em;text-transform:uppercase;color:var(--ac);
  display:block;margin-bottom:18px;
}

.mono{font-family:var(--mono);font-variant-numeric:tabular-nums}

/* spacing utilities: keeps markup free of inline style attributes so the
   production CSP can drop 'unsafe-inline' from style-src without breaking. */
.lead-gap{margin-top:16px}
.body-gap{margin-top:18px}
.body-gap-s{margin-top:14px}
.body-lg{font-size:16px;color:var(--ink-2)}
.body-sm{font-size:14px}
.chips-gap{margin-top:22px}
.sec-tight{padding-top:0}
.sec-alt{background:var(--bg-2);border-block:1px solid var(--line)}

/* ---------- nav: one line, 68px ---------- */
.nav{
  position:fixed;inset:0 0 auto;z-index:80;height:68px;
  background:color-mix(in srgb,var(--bg) 82%,transparent);
  backdrop-filter:blur(16px) saturate(160%);
  border-bottom:1px solid var(--line);
}
.nav-in{display:flex;align-items:center;gap:clamp(18px,3vw,44px);height:68px}
.nav-logo img{height:30px;width:auto}
.nav-links{display:flex;gap:clamp(14px,2vw,30px);margin-left:auto;font-size:14.5px;color:var(--ink-2);font-weight:450}
.nav-links a{position:relative;padding-block:4px;transition:color .18s}
.nav-links a::after{
  content:"";position:absolute;left:0;right:100%;bottom:0;height:1px;
  background:var(--ac);transition:right .28s cubic-bezier(.4,0,.2,1);
}
.nav-links a:hover{color:#fff}
.nav-links a:hover::after{right:0}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  white-space:nowrap;font-weight:600;font-size:14.5px;
  border-radius:var(--r-pill);padding:11px 22px;
  transition:transform .15s,box-shadow .25s,background .2s,border-color .2s;
}
.btn:active{transform:translateY(1px) scale(.985)}
.btn-primary{background:var(--ac);color:#03151A;border:1px solid var(--ac)}
.btn-primary:hover{background:var(--ac-hi);border-color:var(--ac-hi);box-shadow:0 10px 30px -10px rgba(48,168,192,.65)}
.btn-ghost{background:transparent;color:var(--ink);border:1px solid var(--line-2)}
.btn-ghost:hover{border-color:var(--ac);color:#fff;background:var(--ac-dim)}
.btn-lg{padding:15px 30px;font-size:16px}
.nav .btn{padding:9px 18px;font-size:14px}

/* ---------- hero: split, asymmetric. Max 4 text elements. ---------- */
.hero{position:relative;padding-top:clamp(112px,13vw,152px);padding-bottom:clamp(56px,6.5vw,88px);overflow:hidden}
.hero::before{
  content:"";position:absolute;inset:-20% -10% auto auto;width:min(760px,88vw);aspect-ratio:1;
  background:radial-gradient(circle,rgba(48,168,192,.20),transparent 62%);
  filter:blur(30px);pointer-events:none;
}
.hero-grid{
  position:absolute;inset:0;pointer-events:none;opacity:.5;
  background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);
  background-size:64px 64px;
  mask-image:radial-gradient(ellipse 62% 58% at 62% 34%,#000,transparent 76%);
}
.hero-in{position:relative;z-index:2;display:grid;grid-template-columns:1.06fr .94fr;gap:clamp(28px,5vw,64px);align-items:center}
.hero h1 .ac{color:var(--ac-hi)}
.hero .lead{margin-top:22px}
.hero-cta{display:flex;flex-wrap:wrap;gap:12px;margin-top:34px}

.hero-media{position:relative;border-radius:var(--r-surf);overflow:hidden;border:1px solid var(--line);background:linear-gradient(150deg,var(--surf-2),var(--surf))}
.hero-media::after{content:"";position:absolute;inset:0;background:radial-gradient(120% 80% at 20% 0%,rgba(48,168,192,.16),transparent 60%)}
.hero-media img{width:100%;height:auto;padding:clamp(18px,3vw,34px)}

/* ---------- band: 적용 분야 (layout family: divided band) ---------- */
.band{border-block:1px solid var(--line);background:var(--bg-2)}
.band-in{display:grid;grid-template-columns:repeat(5,1fr)}
.band-cell{padding:24px clamp(12px,1.5vw,20px);border-left:1px solid var(--line)}
.band-cell:first-child{border-left:0}
.band-k{font-family:var(--mono);font-size:11px;letter-spacing:.16em;text-transform:uppercase;color:var(--ac);display:block;margin-bottom:8px}
.band-v{font-size:14px;color:var(--ink-2);font-weight:500;line-height:1.5}

/* 5칸 밴드 반응형: 줄이 바뀌는 첫 칸은 왼쪽 선을 지우고, 둘째 줄부터 윗선을 넣는다 */
@media (max-width:1120px){
  .band-in{grid-template-columns:repeat(3,1fr)}
  .band-cell:nth-child(3n+1){border-left:0}
  .band-cell:nth-child(n+4){border-top:1px solid var(--line)}
}
@media (max-width:680px){
  .band-in{grid-template-columns:1fr}
  .band-cell{border-left:0;border-top:1px solid var(--line)}
  .band-cell:first-child{border-top:0}
}

/* ---------- bento: exactly 3 cells, asymmetric, varied backgrounds ---------- */
.bento{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:48px}
.cell{
  position:relative;border:1px solid var(--line);border-radius:var(--r-surf);
  background:var(--surf);padding:clamp(22px,2.6vw,32px);overflow:hidden;
  transition:border-color .25s,transform .25s;
}
.cell:hover{border-color:var(--line-2);transform:translateY(-3px)}
.cell-a{grid-column:span 2}
.cell-b{grid-column:span 1;background:linear-gradient(165deg,var(--surf-2),var(--surf))}
.cell-b::before{
  content:"";position:absolute;inset:0;opacity:.5;
  background-image:repeating-linear-gradient(115deg,transparent 0 13px,rgba(48,168,192,.10) 13px 14px);
  mask-image:linear-gradient(200deg,#000,transparent 72%);
}
.cell-c{grid-column:span 3;display:grid;grid-template-columns:1fr 1.15fr;gap:clamp(20px,3vw,44px);align-items:center}
.cell-media{border-radius:var(--r-media);overflow:hidden;background:linear-gradient(150deg,#E7EFF2,#C2D6DD);padding:18px}
.cell-num{font-family:var(--mono);font-size:12px;color:var(--ac);letter-spacing:.14em;display:block;margin-bottom:14px}
.cell h3{margin-bottom:10px}
.cell .body{margin-top:12px}
.cell-list{margin-top:20px;display:flex;flex-direction:column;gap:10px}
.cell-list li{position:relative;padding-left:18px;font-size:14.5px;color:var(--ink-2)}
.cell-list li::before{content:"";position:absolute;left:0;top:.72em;width:7px;height:1px;background:var(--ac)}
.cell-list b{color:#fff;font-weight:600}

/* ---------- feature: full-width, image + grouped spec clusters ---------- */
.feat{display:grid;grid-template-columns:.95fr 1.05fr;gap:clamp(28px,5vw,68px);align-items:center}
.feat-media{border:1px solid var(--line);border-radius:var(--r-surf);overflow:hidden;background:linear-gradient(150deg,var(--surf-2),var(--surf));padding:clamp(18px,3vw,32px)}
.tag{
  display:inline-flex;align-items:center;gap:7px;font-family:var(--mono);font-size:11px;
  letter-spacing:.14em;text-transform:uppercase;color:var(--ac);
  border:1px solid rgba(48,168,192,.34);background:var(--ac-dim);
  border-radius:var(--r-pill);padding:5px 13px;margin-bottom:18px;
}
.tag i{width:5px;height:5px;border-radius:50%;background:var(--ac);box-shadow:0 0 9px var(--ac)}

/* spec clusters: 3 groups, one sparse divider each. No border-b per row. */
.clusters{margin-top:32px;display:flex;flex-direction:column;gap:24px}
.cluster{padding-top:20px;border-top:1px solid var(--line)}
.cluster-k{font-family:var(--mono);font-size:11px;letter-spacing:.16em;text-transform:uppercase;color:var(--mut);margin-bottom:12px}
.cluster-v{display:flex;flex-wrap:wrap;gap:8px}
.chip{
  font-family:var(--mono);font-size:12.5px;color:var(--ink-2);
  border:1px solid var(--line);background:var(--bg-2);
  border-radius:var(--r-pill);padding:6px 13px;
}

/* ---------- paired detail panels ---------- */
.panels{display:flex;flex-direction:column;gap:16px;margin-top:48px}
.panel{border:1px solid var(--line);border-radius:var(--r-surf);background:var(--surf);overflow:hidden}
.panel-top{display:grid;grid-template-columns:1.25fr 1fr;gap:clamp(20px,3vw,40px);align-items:center;padding:clamp(24px,3vw,36px)}
.panel-media{border-radius:var(--r-media);overflow:hidden;background:linear-gradient(150deg,#E7EFF2,#C2D6DD);padding:16px}
.panel-bot{border-top:1px solid var(--line);background:var(--bg-2);padding:clamp(24px,3vw,36px)}
.kv{display:grid;grid-template-columns:repeat(2,1fr);gap:18px 28px}
.kv-item h4{margin-bottom:5px}
.kv-item p{font-size:14px;color:var(--mut);line-height:1.6}
.apply{display:flex;flex-direction:column;gap:9px;margin-top:18px}
.apply li{font-size:14.5px;color:var(--ink-2);padding-left:18px;position:relative}
.apply li::before{content:"";position:absolute;left:0;top:.72em;width:7px;height:1px;background:var(--ac)}
.apply b{color:#fff;font-weight:600}

/* ---------- editorial + quote ---------- */
.edit{display:grid;grid-template-columns:1fr 1fr;gap:clamp(28px,5vw,72px);align-items:start}
.quote{margin-top:34px;border-left:2px solid var(--ac);padding-left:clamp(20px,2.6vw,30px)}
.quote p{font-size:clamp(18px,1.9vw,24px);line-height:1.55;color:#fff;letter-spacing:-.02em}
.quote cite{display:block;margin-top:18px;font-style:normal;font-family:var(--mono);font-size:12.5px;letter-spacing:.1em;color:var(--mut);text-transform:uppercase}

/* ---------- cert rail: horizontal scroll-snap ---------- */
.rail{
  display:grid;grid-auto-flow:column;grid-auto-columns:minmax(190px,1fr);gap:16px;
  margin-top:44px;overflow-x:auto;scroll-snap-type:x mandatory;
  padding-bottom:14px;scrollbar-width:thin;scrollbar-color:var(--line-2) transparent;
}
.rail::-webkit-scrollbar{height:6px}
.rail::-webkit-scrollbar-thumb{background:var(--line-2);border-radius:var(--r-pill)}
.rail-item{scroll-snap-align:start}
.rail-img{background:#fff;border-radius:var(--r-media);padding:10px;transition:transform .25s,box-shadow .25s}
.rail-item:hover .rail-img{transform:translateY(-4px);box-shadow:0 18px 40px -18px rgba(48,168,192,.55)}
.rail-img img{border-radius:4px;width:100%}
.rail-item h4{margin-top:14px;font-size:13.5px;font-weight:500;color:var(--ink-2);text-align:center}

/* ---------- timeline: grouped into eras, sparse dividers ---------- */
.era{margin-top:52px}
.era-h{display:flex;align-items:baseline;gap:16px;padding-bottom:16px;border-bottom:1px solid var(--line)}
.era-r{font-family:var(--mono);font-size:clamp(22px,2.8vw,34px);font-weight:600;color:#fff;letter-spacing:-.02em}
.era-t{font-size:14.5px;color:var(--ac)}
.era-rows{margin-top:8px}
.row{display:grid;grid-template-columns:96px 1fr;gap:clamp(14px,2vw,28px);padding:16px 0;align-items:start}
.row-y{font-family:var(--mono);font-size:14px;color:var(--mut);padding-top:2px;font-variant-numeric:tabular-nums}
.row-e{display:flex;flex-direction:column;gap:7px}
.row-e span{font-size:15px;color:var(--ink-2);position:relative;padding-left:18px}
.row-e span::before{content:"";position:absolute;left:0;top:.72em;width:7px;height:1px;background:var(--line-2)}

/* ---------- contact band ---------- */
.cta{border:1px solid var(--line);border-radius:var(--r-surf);background:linear-gradient(140deg,var(--surf-2),var(--surf));position:relative;overflow:hidden}
.cta::before{content:"";position:absolute;inset:auto auto -40% -10%;width:520px;aspect-ratio:1;background:radial-gradient(circle,rgba(48,168,192,.20),transparent 62%);filter:blur(24px)}
.cta-in{position:relative;display:grid;grid-template-columns:1fr auto;gap:clamp(26px,4vw,56px);align-items:center;padding:clamp(30px,4.2vw,54px)}
.cinfo{display:flex;flex-direction:column;gap:11px;margin-top:24px}
.cinfo div{display:flex;gap:14px;font-size:14.5px;color:var(--ink-2)}
.cinfo .k{font-family:var(--mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--mut);min-width:52px;padding-top:4px}
.cta-act{display:flex;flex-direction:column;align-items:flex-start;gap:14px}
.tel{font-family:var(--mono);font-size:clamp(24px,2.8vw,34px);font-weight:600;color:#fff;letter-spacing:-.02em;transition:color .2s}
.tel:hover{color:var(--ac-hi)}

/* ---------- footer ---------- */
.foot{border-top:1px solid var(--line);padding-block:44px;background:var(--bg-2)}
.foot-in{display:flex;flex-wrap:wrap;gap:22px;align-items:center;justify-content:space-between}
.foot img{height:26px;width:auto;opacity:.85}
.foot p{font-size:13px;color:var(--mut);line-height:1.9}

/* ---------- motion (MOTION_INTENSITY 5): entrance reveal only, IO-driven ---------- */
.rv{opacity:0;transform:translateY(18px);transition:opacity .7s cubic-bezier(.16,1,.3,1),transform .7s cubic-bezier(.16,1,.3,1)}
.rv.in{opacity:1;transform:none}
.rv-d1{transition-delay:.07s}
.rv-d2{transition-delay:.14s}

:focus-visible{outline:2px solid var(--ac-hi);outline-offset:3px;border-radius:4px}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms !important;transition-duration:.01ms !important}
  .rv{opacity:1;transform:none}
}

/* ---------- explicit mobile collapse per layout family ---------- */
@media (max-width:1000px){
  .hero-in{grid-template-columns:1fr;gap:36px}
  .hero-media{order:-1}
  .bento{grid-template-columns:1fr}
  .cell-a,.cell-b,.cell-c{grid-column:auto}
  .cell-c{grid-template-columns:1fr;gap:22px}
  .feat{grid-template-columns:1fr;gap:32px}
  .panel-top{grid-template-columns:1fr;gap:24px}
  .edit{grid-template-columns:1fr;gap:30px}
  .cta-in{grid-template-columns:1fr}
}
@media (max-width:720px){
  .nav-links{display:none}
  .kv{grid-template-columns:1fr}
  .row{grid-template-columns:1fr;gap:6px}
  .row-y{font-size:13px}
}