/* ============================================================
   Rennen ITB by JSR Engineering - main.css
   Premium technical / dark graphite / silver + bronze
   Mobile-first. No frameworks.
   ============================================================ */

:root{
  --ink:#14161a;
  --ink-2:#1a1d22;
  --ink-3:#22262d;
  --line:#2c313a;
  --line-soft:#23272f;
  --txt:#cfd3da;
  --txt-dim:#8d93a0;
  --head:#f1f2f4;
  --bronze:#b98a5a;
  --bronze-hi:#d8b289;
  --bronze-dim:rgba(185,138,90,.14);
  --silver:#aeb4bf;
  --good:#7fb069;
  --radius:10px;
  --wrap:1140px;
  --font:'Archivo',system-ui,-apple-system,'Segoe UI',sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,'SF Mono',Menlo,monospace;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--ink);color:var(--txt);
  font-family:var(--font);font-size:1rem;line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
img,svg{max-width:100%;height:auto;display:block}
a{color:var(--bronze-hi);text-decoration:none}
a:hover{color:var(--head)}
:focus-visible{outline:2px solid var(--bronze-hi);outline-offset:3px;border-radius:2px}

h1,h2,h3,h4{color:var(--head);font-weight:600;line-height:1.15;margin:0 0 .6em;letter-spacing:-.015em}
h1{font-size:clamp(2.1rem,6.5vw,3.7rem);font-weight:700;letter-spacing:-.03em}
h2{font-size:clamp(1.55rem,4vw,2.3rem)}
h3{font-size:1.18rem}
p{margin:0 0 1.1em}
.lede{font-size:clamp(1.05rem,2.4vw,1.25rem);color:var(--txt);max-width:42em}
.dim{color:var(--txt-dim)}
.small{font-size:.85rem}

.wrap{width:min(var(--wrap),100% - 2.5rem);margin-inline:auto}
section{padding:4.5rem 0}
@media(min-width:760px){section{padding:6.5rem 0}}

/* eyebrow + tapered rule (signature) */
.eyebrow{
  font-family:var(--mono);font-size:.72rem;letter-spacing:.22em;
  text-transform:uppercase;color:var(--bronze);margin:0 0 1rem;display:block;
}
.taper{height:14px;margin:.4rem 0 1.6rem;overflow:visible}
.taper polygon{fill:var(--bronze);opacity:.85}

/* ---------- nav ---------- */
.site-head{
  position:sticky;top:0;z-index:50;
  background:rgba(20,22,26,.86);backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line-soft);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:baseline;gap:.55rem;color:var(--head)}
.brand b{font-weight:700;letter-spacing:.04em;font-size:1.02rem}
.brand-logo{height:30px;width:auto;display:block}
.site-foot .brand-logo{height:34px;margin-bottom:.4rem}
.brand span{font-family:var(--mono);font-size:.62rem;letter-spacing:.18em;color:var(--txt-dim);text-transform:uppercase}
.nav-links{display:none;list-style:none;margin:0;padding:0;gap:1.6rem;align-items:center}
.nav-links a{font-size:.88rem;color:var(--txt);letter-spacing:.02em}
.nav-links a:hover,.nav-links a[aria-current="page"]{color:var(--bronze-hi)}
.nav-cta{font-family:var(--mono);font-size:.74rem;letter-spacing:.1em;text-transform:uppercase;
  border:1px solid var(--bronze);color:var(--bronze-hi);padding:.5rem .9rem;border-radius:6px}
.nav-cta:hover{background:var(--bronze-dim)}
.nav-toggle{display:inline-flex;flex-direction:column;gap:5px;background:none;border:0;padding:.6rem;cursor:pointer}
.nav-toggle span{width:22px;height:2px;background:var(--head);transition:transform .25s,opacity .25s}
.nav-open .nav-toggle span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-open .nav-toggle span:nth-child(2){opacity:0}
.nav-open .nav-toggle span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}
.mobile-menu{display:none;border-top:1px solid var(--line-soft);padding:1rem 0 1.4rem}
.nav-open .mobile-menu{display:block}
.mobile-menu a{display:block;padding:.65rem 0;color:var(--txt);font-size:1rem;border-bottom:1px solid var(--line-soft)}
.mobile-menu a[aria-current="page"]{color:var(--bronze-hi)}
@media(min-width:920px){
  .nav-links{display:flex}
  .nav-toggle,.mobile-menu{display:none!important}
}

/* ---------- buttons ---------- */
.btn{
  display:inline-block;font-family:var(--mono);font-size:.8rem;letter-spacing:.12em;
  text-transform:uppercase;padding:.85rem 1.5rem;border-radius:7px;border:1px solid transparent;
  transition:background .2s,color .2s,border-color .2s;cursor:pointer;
}
.btn-solid{background:var(--bronze);color:#15110c;font-weight:600}
.btn-solid:hover{background:var(--bronze-hi);color:#15110c}
.btn-ghost{border-color:var(--line);color:var(--head)}
.btn-ghost:hover{border-color:var(--bronze);color:var(--bronze-hi)}
.btn-row{display:flex;flex-wrap:wrap;gap:.8rem;margin-top:1.8rem}
.hero .btn-row{flex-wrap:nowrap}
.hero .btn{white-space:nowrap}
@media(max-width:520px){.hero .btn-row{flex-wrap:wrap}.hero .btn-row .btn{flex:1 1 auto;text-align:center}}

/* ---------- hero ---------- */
.hero{
  padding:4.5rem 0 4rem;position:relative;overflow:hidden;
  background:
    radial-gradient(900px 420px at 78% -10%,rgba(185,138,90,.10),transparent 65%),
    radial-gradient(700px 380px at -10% 110%,rgba(140,150,165,.06),transparent 60%),
    var(--ink);
  border-bottom:1px solid var(--line-soft);
}
@media(min-width:920px){.hero{padding:6.5rem 0 6rem}}
.hero-grid{display:grid;gap:3rem;align-items:center}
@media(min-width:920px){.hero-grid{grid-template-columns:.72fr 1.28fr;gap:3rem}}
@media(min-width:1280px){.hero-grid{grid-template-columns:.62fr 1.38fr}}
.hero-art{filter:drop-shadow(0 18px 40px rgba(0,0,0,.45))}

/* spec strip */
.spec-strip{
  display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--line);
  border-radius:var(--radius);overflow:hidden;background:var(--ink-2);
}
@media(min-width:760px){.spec-strip{grid-template-columns:repeat(4,1fr)}}
.spec-strip div{padding:1.2rem 1.3rem;border-top:1px solid var(--line-soft)}
.spec-strip div:nth-child(-n+2){border-top:0}
@media(min-width:760px){.spec-strip div{border-top:0;border-left:1px solid var(--line-soft)}.spec-strip div:first-child{border-left:0}}
.spec-strip b{display:block;color:var(--head);font-family:var(--mono);font-size:.92rem;font-weight:500;margin-bottom:.25rem}
.spec-strip span{font-size:.78rem;color:var(--txt-dim);letter-spacing:.04em}

/* ---------- cards & grids ---------- */
.grid{display:grid;gap:1.2rem}
@media(min-width:760px){.grid-2{grid-template-columns:1fr 1fr}.grid-3{grid-template-columns:repeat(3,1fr)}}
.card{
  background:var(--ink-2);border:1px solid var(--line);border-radius:var(--radius);
  padding:1.7rem 1.6rem;position:relative;
}
.card::before{
  content:"";position:absolute;inset:0 auto auto 0;width:100%;height:2px;
  background:linear-gradient(90deg,var(--bronze),transparent 70%);
  opacity:0;transition:opacity .25s;border-radius:var(--radius) var(--radius) 0 0;
}
.card:hover::before{opacity:1}
.card h3{margin-top:.2rem}
.card .mono-tag{font-family:var(--mono);font-size:.68rem;letter-spacing:.16em;color:var(--bronze);text-transform:uppercase}
.card-link{display:inline-block;margin-top:.6rem;font-family:var(--mono);font-size:.76rem;letter-spacing:.1em;text-transform:uppercase}

/* ---------- spec tables ---------- */
.spec-table{width:100%;border-collapse:collapse;font-size:.92rem}
.spec-table th,.spec-table td{padding:.8rem .9rem;border-bottom:1px solid var(--line-soft);text-align:left;vertical-align:top}
.spec-table th{color:var(--txt-dim);font-weight:500;font-family:var(--mono);font-size:.74rem;letter-spacing:.1em;text-transform:uppercase;width:42%}
.spec-table td{color:var(--head)}
.table-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:var(--ink-2)}
.cmp-table{width:100%;border-collapse:collapse;font-size:.88rem;min-width:560px}
.cmp-table th,.cmp-table td{padding:.85rem 1rem;border-bottom:1px solid var(--line-soft);text-align:left}
.cmp-table thead th{font-family:var(--mono);font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--bronze)}
.cmp-table tbody th{color:var(--txt-dim);font-weight:500}
.cmp-table td{color:var(--head)}

/* ---------- media / video placeholders ---------- */
.media-ph{
  position:relative;border:1px solid var(--line);border-radius:var(--radius);
  background:
    radial-gradient(420px 200px at 50% 0%,rgba(185,138,90,.08),transparent 70%),
    var(--ink-2);
  aspect-ratio:16/9;display:flex;align-items:center;justify-content:center;
  flex-direction:column;gap:.8rem;text-align:center;padding:1.5rem;
}
.media-ph .play{
  width:58px;height:58px;border-radius:50%;border:1px solid var(--bronze);
  display:flex;align-items:center;justify-content:center;color:var(--bronze-hi);
}
.media-ph p{margin:0;font-family:var(--mono);font-size:.74rem;letter-spacing:.12em;text-transform:uppercase;color:var(--txt-dim)}

/* ---------- flow demo (signature interactive) ---------- */
.flow-demo{border:1px solid var(--line);border-radius:var(--radius);background:var(--ink-2);padding:1.6rem;overflow:hidden}
.flow-grid{display:grid;gap:1.6rem}
@media(min-width:820px){.flow-grid{grid-template-columns:1fr 1fr}}
.flow-pane h3{font-size:.95rem;font-family:var(--mono);font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--txt-dim)}
.flow-pane.jsr h3{color:var(--bronze-hi)}
.flow-svg{width:100%;background:var(--ink);border:1px solid var(--line-soft);border-radius:8px}
.flow-line{stroke:var(--silver);stroke-width:1.6;fill:none;stroke-dasharray:7 9;opacity:.75;
  animation:flow 1.2s linear infinite}
.jsr .flow-line{stroke:var(--bronze-hi)}
@keyframes flow{to{stroke-dashoffset:-32}}
.flow-meter{margin-top:.9rem}
.flow-meter .bar{height:6px;background:var(--ink-3);border-radius:3px;overflow:hidden}
.flow-meter .bar i{display:block;height:100%;background:var(--silver);width:50%;transition:width .25s}
.jsr .flow-meter .bar i{background:var(--bronze)}
.flow-meter .val{font-family:var(--mono);font-size:.78rem;color:var(--txt-dim);margin-top:.4rem;display:block}
.throttle-ctl{margin-top:1.8rem}
.throttle-ctl label{display:flex;justify-content:space-between;font-family:var(--mono);font-size:.76rem;letter-spacing:.1em;text-transform:uppercase;color:var(--txt-dim);margin-bottom:.6rem}
.throttle-ctl output{color:var(--bronze-hi)}
input[type=range]{width:100%;accent-color:var(--bronze);height:28px}

/* ---------- selector / configurator ---------- */
.tool{border:1px solid var(--line);border-radius:var(--radius);background:var(--ink-2);padding:1.7rem}
@media(min-width:760px){.tool{padding:2.2rem}}
.field{margin-bottom:1.3rem}
.field>label,fieldset legend{display:block;font-family:var(--mono);font-size:.74rem;letter-spacing:.12em;text-transform:uppercase;color:var(--txt-dim);margin-bottom:.55rem}
select,input[type=text],input[type=email],input[type=tel],textarea{
  width:100%;background:var(--ink);border:1px solid var(--line);border-radius:7px;
  color:var(--head);padding:.8rem .9rem;font-family:var(--font);font-size:.95rem;
}
select:focus,input:focus,textarea:focus{border-color:var(--bronze);outline:none}
textarea{min-height:120px;resize:vertical}
fieldset{border:0;padding:0;margin:0 0 1.3rem}
.choices{display:grid;gap:.6rem}
@media(min-width:600px){.choices{grid-template-columns:1fr 1fr}}
.choices label{
  display:flex;gap:.6rem;align-items:flex-start;border:1px solid var(--line);
  border-radius:8px;padding:.75rem .85rem;cursor:pointer;font-size:.9rem;color:var(--txt);
}
.choices label:has(:checked){border-color:var(--bronze);background:var(--bronze-dim);color:var(--head)}
.choices input{accent-color:var(--bronze);margin-top:.2rem}
.result-card{margin-top:1.6rem;border:1px solid var(--bronze);border-radius:var(--radius);background:var(--bronze-dim);padding:1.5rem}
.result-card[hidden]{display:none}
.result-card h3{color:var(--bronze-hi)}
.summary-box{font-family:var(--mono);font-size:.82rem;background:var(--ink);border:1px solid var(--line);border-radius:8px;padding:1rem;white-space:pre-line;color:var(--txt)}

/* ---------- forms ---------- */
.form-note{font-size:.82rem;color:var(--txt-dim)}
.hp{position:absolute;left:-9999px}

/* ---------- callouts / steps ---------- */
.callout{border-left:2px solid var(--bronze);background:var(--ink-2);border-radius:0 var(--radius) var(--radius) 0;padding:1.3rem 1.5rem;margin:1.8rem 0}
.steps{list-style:none;margin:0;padding:0;counter-reset:step;display:grid;gap:1rem}
.steps li{background:var(--ink-2);border:1px solid var(--line);border-radius:var(--radius);padding:1.4rem 1.5rem 1.4rem 4.4rem;position:relative;counter-increment:step}
.steps li::before{
  content:counter(step,decimal-leading-zero);position:absolute;left:1.4rem;top:1.35rem;
  font-family:var(--mono);color:var(--bronze);font-size:.95rem;
}
.steps b{color:var(--head);display:block;margin-bottom:.2rem}

/* faq */
details{border:1px solid var(--line);border-radius:var(--radius);background:var(--ink-2);margin-bottom:.8rem}
summary{cursor:pointer;padding:1.1rem 1.3rem;color:var(--head);font-weight:500;list-style:none;display:flex;justify-content:space-between;gap:1rem}
summary::after{content:"+";font-family:var(--mono);color:var(--bronze)}
details[open] summary::after{content:"–"}
details>div{padding:0 1.3rem 1.2rem;color:var(--txt)}

/* ---------- breadcrumb ---------- */
.crumbs{font-family:var(--mono);font-size:.72rem;letter-spacing:.08em;text-transform:uppercase;color:var(--txt-dim);padding:1.2rem 0 0}
.crumbs a{color:var(--txt-dim)}
.crumbs a:hover{color:var(--bronze-hi)}
.crumbs span{color:var(--bronze)}

/* ---------- footer ---------- */
.site-foot{border-top:1px solid var(--line-soft);background:#101216;padding:3.5rem 0 2.5rem;margin-top:2rem}
.foot-grid{display:grid;gap:2.2rem}
@media(min-width:760px){.foot-grid{grid-template-columns:1.4fr 1fr 1fr 1fr}}
.site-foot h4{font-family:var(--mono);font-size:.7rem;letter-spacing:.18em;text-transform:uppercase;color:var(--txt-dim);font-weight:500}
.site-foot ul{list-style:none;margin:0;padding:0}
.site-foot li{margin:.45rem 0}
.site-foot a{color:var(--txt);font-size:.9rem}
.site-foot a:hover{color:var(--bronze-hi)}
.foot-legal{margin-top:2.6rem;padding-top:1.4rem;border-top:1px solid var(--line-soft);font-size:.78rem;color:var(--txt-dim);display:flex;flex-wrap:wrap;gap:.6rem 1.6rem;justify-content:space-between}

/* ---------- reveal ---------- */
.js .reveal{opacity:0;transform:translateY(16px);transition:opacity .6s ease,transform .6s ease}
.js .reveal.in{opacity:1;transform:none}

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

/* ---------- photography ---------- */
.figure{margin:0;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:var(--ink-2)}
.figure img{width:100%;height:auto;display:block}
.figure figcaption{font-family:var(--mono);font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--txt-dim);padding:.8rem 1.1rem;border-top:1px solid var(--line-soft)}
.photo-grid{display:grid;gap:1.2rem}
@media(min-width:760px){.photo-grid{grid-template-columns:1fr 1fr}.photo-grid.thirds{grid-template-columns:repeat(3,1fr)}.photo-grid.quad{grid-template-columns:repeat(4,1fr)}}
@media(max-width:759px){.photo-grid.quad{grid-template-columns:1fr 1fr}}
.photo-grid.quad .figure img{height:170px;object-fit:cover;width:100%}
.card-img{width:calc(100% + 3.2rem);max-width:none;margin:-1.7rem -1.6rem 1.2rem;border-radius:var(--radius) var(--radius) 0 0;display:block;height:210px;object-fit:cover;object-position:center;border-bottom:1px solid var(--line-soft);background:#cfd0d2}
.hero-photo{border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:0 24px 60px rgba(0,0,0,.45)}
.hero-photo img{display:block;width:100%;height:auto}

/* ---------- system-layer toggles ---------- */
.lab-toggles{display:flex;flex-wrap:wrap;gap:.6rem;margin-top:1.1rem}
.lab-toggles label{font-family:var(--mono);font-size:.72rem;letter-spacing:.08em;text-transform:uppercase;color:var(--txt-dim);border:1px solid var(--line);border-radius:6px;padding:.45rem .7rem;cursor:pointer;display:flex;gap:.45rem;align-items:center}
.lab-toggles label:has(:checked){border-color:var(--bronze);color:var(--bronze-hi);background:var(--bronze-dim)}
.lab-toggles input{accent-color:var(--bronze);margin:0}

/* ---------- gallery ---------- */
.dk-statement{padding:5rem 0 3.5rem;text-align:left}
.dk-statement h1{font-size:clamp(2.8rem,11vw,7.5rem);font-weight:700;letter-spacing:-.04em;line-height:.95;margin:0 0 .3em;color:var(--head)}
.dk-statement h1 span{color:var(--bronze)}
.gallery{display:grid;grid-template-columns:repeat(2,1fr);gap:.9rem}
@media(min-width:700px){.gallery{grid-template-columns:repeat(3,1fr)}}
.gallery .figure{margin:0;cursor:zoom-in;transition:border-color .2s;aspect-ratio:1/1}
.gallery .figure img{width:100%;height:100%;object-fit:cover}
.gallery .figure figcaption{display:none}
.gallery .figure:hover,.gallery .figure:focus-visible{border-color:var(--bronze)}
.gal-divider{grid-column:1/-1;font-family:var(--mono);font-size:.72rem;letter-spacing:.2em;text-transform:uppercase;color:var(--bronze);padding:1.6rem 0 .2rem;border-bottom:1px solid var(--line-soft);margin-bottom:.3rem}
.gal-hero{margin:2.4rem 0 1.6rem}
.lightbox{border:0;padding:0;background:rgba(12,13,16,.96);max-width:100vw;max-height:100vh;width:100vw;height:100vh;display:none;align-items:center;justify-content:center}
.lightbox[open]{display:flex}
.lightbox::backdrop{background:rgba(12,13,16,.96)}
.lightbox figure{margin:0;max-width:min(1100px,92vw);text-align:center}
.lightbox img{max-width:100%;max-height:82vh;width:auto;height:auto;border-radius:8px;margin-inline:auto}
.lightbox figcaption{font-family:var(--mono);font-size:.76rem;letter-spacing:.1em;text-transform:uppercase;color:var(--txt-dim);margin-top:1rem}
.lb-btn{position:fixed;top:50%;transform:translateY(-50%);background:rgba(26,29,34,.85);border:1px solid var(--line);color:var(--head);width:46px;height:46px;border-radius:50%;cursor:pointer;font-size:1.2rem}
.lb-prev{left:1rem}.lb-next{right:1rem}
.lb-close{position:fixed;top:1rem;right:1rem;transform:none}
.lb-btn:hover{border-color:var(--bronze);color:var(--bronze-hi)}