/* ============================================================
   Kensington Sash — case study layer
   Loaded after site-v2.css, on case-study-*.html ONLY.
   Every selector is namespaced .cs3-*. Nothing here can reach
   another page on the site.

   Signature device: the glazing bar. A 3px hairline lattice,
   used in exactly three places — the pane panel, the photo
   grid, the section rules. Nowhere else.
   ============================================================ */

.cs3{
  --char:#2c2b26;        /* charcoal, the v2 ink */
  --cream:#F4F1EB;
  --stone:#E7E2D9;
  --accent:#9c9484;      /* warm grey, the brass stand-in */
  --hair:rgba(44,43,38,.14);
  --hair-w:rgba(255,255,255,.10);
  --body:#5c5a52;
  --head-pad:clamp(150px,12.5vw,188px);
}

/* ============ HERO ============ */
.cs3-hero{
  background:var(--cream);
  padding:var(--head-pad) 6vw 0;
  position:relative;
}
.cs3-hero-inner{
  max-width:1320px;margin:0 auto;
  display:grid;grid-template-columns:1.12fr .88fr;
  gap:clamp(2rem,5vw,5rem);
  align-items:end;
}

/* Left ---------------------------------------------------- */
.cs3-idx{
  display:flex;align-items:center;gap:.85rem;
  font-family:'Montserrat',sans-serif;font-size:.7rem;font-weight:600;
  letter-spacing:.18em;color:var(--accent);margin-bottom:2.4rem;
}
.cs3-idx::after{content:'';flex:1;height:1px;background:var(--hair);max-width:120px}

.cs3-eyebrow{
  display:block;font-family:'Montserrat',sans-serif;
  font-size:.68rem;font-weight:600;letter-spacing:.2em;text-transform:uppercase;
  color:var(--accent);margin-bottom:1.25rem;
}
.cs3-title{
  font-family:'Newsreader',Georgia,serif;font-weight:300;
  font-size:clamp(2.3rem,4.4vw,4rem);line-height:1.02;
  letter-spacing:-.012em;color:var(--char);margin:0 0 2rem;
}
.cs3-title em{font-style:italic;color:var(--accent)}

/* The meta rail. Three facts, hairline dividers, nothing more. */
.cs3-rail{
  display:flex;flex-wrap:wrap;
  border-top:1px solid var(--hair);
  padding-top:1.35rem;margin-bottom:3.6rem;
}
.cs3-rail div{padding-right:2.2rem;margin-right:2.2rem;border-right:1px solid var(--hair)}
.cs3-rail div:last-child{border-right:0;padding-right:0;margin-right:0}
.cs3-rail dt{
  font-family:'Montserrat',sans-serif;font-size:.62rem;font-weight:600;
  letter-spacing:.17em;text-transform:uppercase;color:var(--accent);margin-bottom:.42rem;
}
.cs3-rail dd{
  margin:0;font-family:'Newsreader',Georgia,serif;font-weight:400;
  font-size:1.12rem;color:var(--char);line-height:1.25;
}

/* Right — the photograph, dropped so it breaks the hero edge -- */
.cs3-plate{
  position:relative;background:var(--char);
  aspect-ratio:4/5;overflow:hidden;
  margin-bottom:-5.5rem;   /* the overlap. This is the move. */
  z-index:2;
}
.cs3-plate img{width:100%;height:100%;object-fit:cover;display:block}

/* No photograph? Then a sash. Six panes, drawn in glazing bars. */
.cs3-pane{
  position:relative;background:var(--char);
  aspect-ratio:4/5;overflow:hidden;
  margin-bottom:-5.5rem;z-index:2;
  display:grid;grid-template-columns:1fr 1fr;grid-template-rows:repeat(3,1fr);
  gap:3px;padding:3px;
}
.cs3-pane span{background:#31302a;display:block}
.cs3-pane b{
  position:absolute;right:1.6rem;bottom:1.1rem;z-index:2;
  font-family:'Newsreader',Georgia,serif;font-weight:300;font-style:italic;
  font-size:clamp(4rem,7vw,6.5rem);line-height:1;
  color:rgba(255,255,255,.13);letter-spacing:-.02em;
}
.cs3-pane i{
  position:absolute;left:1.7rem;bottom:1.6rem;z-index:2;font-style:normal;
  font-family:'Montserrat',sans-serif;font-size:.6rem;font-weight:600;
  letter-spacing:.2em;text-transform:uppercase;color:rgba(255,255,255,.34);
}

/* ============ SPECIFICATION SCHEDULE ============ */
.cs3-spec{background:var(--char);padding:8rem 6vw 4.2rem}
.cs3-spec-inner{max-width:1320px;margin:0 auto}
.cs3-spec-h{
  font-family:'Montserrat',sans-serif;font-size:.68rem;font-weight:600;
  letter-spacing:.2em;text-transform:uppercase;color:var(--accent);
  padding-bottom:1.6rem;margin-bottom:.4rem;border-bottom:1px solid var(--hair-w);
}
.cs3-sched{
  display:grid;grid-template-columns:1fr 1fr;
  column-gap:clamp(2rem,6vw,6rem);
}
.cs3-sched div{
  display:grid;grid-template-columns:minmax(120px,180px) 1fr;
  gap:1.5rem;align-items:baseline;
  padding:1.05rem 0;border-bottom:1px solid var(--hair-w);
}
.cs3-sched dt{
  font-family:'Montserrat',sans-serif;font-size:.63rem;font-weight:600;
  letter-spacing:.16em;text-transform:uppercase;color:var(--accent);
}
.cs3-sched dd{
  margin:0;font-family:'Newsreader',Georgia,serif;font-weight:400;
  font-size:1.02rem;line-height:1.45;color:var(--cream);
}

/* ============ WRITE-UP ============ */
.cs3-read{background:var(--cream);padding:5.5rem 6vw}
.cs3-read-inner{
  max-width:1320px;margin:0 auto;
  display:grid;grid-template-columns:260px 1fr;gap:clamp(2rem,6vw,6rem);
  align-items:start;
}
.cs3-rail-left{position:sticky;top:190px}
.cs3-rail-left .cs3-eyebrow{margin-bottom:1.6rem}
.cs3-btn{
  display:inline-block;font-family:'Montserrat',sans-serif;
  font-size:.68rem;font-weight:600;letter-spacing:.14em;text-transform:uppercase;
  padding:1.05rem 2rem;background:var(--char);color:var(--cream);
  text-decoration:none;transition:background .2s;
}
.cs3-btn:hover{background:#43413a}
.cs3-back{
  display:block;margin-top:1.5rem;font-family:'Montserrat',sans-serif;
  font-size:.72rem;letter-spacing:.05em;color:var(--body);text-decoration:none;
}
.cs3-back:hover{color:var(--char)}

.cs3-copy{max-width:66ch}
.cs3-lead{
  font-family:'Newsreader',Georgia,serif;font-weight:300;
  font-size:clamp(1.45rem,2.15vw,1.95rem);line-height:1.42;
  color:var(--char);margin:0 0 2.2rem;
  padding-left:1.6rem;border-left:2px solid var(--accent);
}
.cs3-copy p{
  font-family:'Montserrat',sans-serif;font-size:.93rem;line-height:1.95;
  color:var(--body);margin:0 0 1.35rem;
}
.cs3-copy p:last-child{margin-bottom:0}
.cs3-copy strong{color:var(--char);font-weight:600}
.cs3-copy a,.cs3-copy .il{
  color:var(--char);text-decoration:none;
  border-bottom:1px solid var(--accent);transition:border-color .2s;
}
.cs3-copy a:hover{border-bottom-color:var(--char)}

/* A holding state that looks deliberate, not broken. */
.cs3-hold{
  border:1px solid var(--hair);padding:2.6rem 2.4rem;background:transparent;
}
.cs3-hold h3{
  font-family:'Newsreader',Georgia,serif;font-weight:300;font-size:1.5rem;
  color:var(--char);margin:0 0 .7rem;
}
.cs3-hold p{margin-bottom:0}

/* ============ PHOTO LATTICE ============ */
.cs3-plates{background:var(--cream);padding:0 6vw 5.5rem}
.cs3-plates-inner{
  max-width:1320px;margin:0 auto;
  display:grid;grid-template-columns:1fr 1fr;gap:3px;
  background:var(--stone);padding:3px;   /* the glazing bars */
}
.cs3-plates figure{margin:0;overflow:hidden;background:var(--char);aspect-ratio:4/3}
.cs3-plates figure.wide{grid-column:1 / -1;aspect-ratio:16/7}
.cs3-plates img{width:100%;height:100%;object-fit:cover;display:block;transition:transform .6s ease}
.cs3-plates figure:hover img{transform:scale(1.035)}

/* ============ NEXT PROJECT ============ */
.cs3-next{background:var(--char);padding:4.5rem 6vw}
.cs3-next-inner{
  max-width:1320px;margin:0 auto;
  display:flex;align-items:flex-end;justify-content:space-between;
  gap:2.5rem;flex-wrap:wrap;
}
.cs3-next a.cs3-next-link{text-decoration:none;display:block}
.cs3-next .cs3-eyebrow{color:var(--accent)}
.cs3-next-t{
  font-family:'Newsreader',Georgia,serif;font-weight:300;
  font-size:clamp(1.6rem,2.9vw,2.5rem);line-height:1.12;color:var(--cream);
  margin:0;transition:color .2s;
}
.cs3-next a.cs3-next-link:hover .cs3-next-t{color:var(--accent)}
.cs3-next-t span{display:inline-block;transition:transform .25s}
.cs3-next a.cs3-next-link:hover .cs3-next-t span{transform:translateX(7px)}
.cs3-btn-light{
  display:inline-block;font-family:'Montserrat',sans-serif;
  font-size:.68rem;font-weight:600;letter-spacing:.14em;text-transform:uppercase;
  padding:1.05rem 2rem;background:var(--cream);color:var(--char);
  text-decoration:none;transition:opacity .2s;white-space:nowrap;
}
.cs3-btn-light:hover{opacity:.82}

/* ============ RESPONSIVE ============ */
@media(max-width:1000px){
  .cs3-read-inner{grid-template-columns:1fr;gap:2.5rem}
  .cs3-rail-left{position:static}
  .cs3-sched{grid-template-columns:1fr}
}
@media(max-width:820px){
  .cs3-hero{padding:clamp(120px,26vw,150px) 6vw 0}
  .cs3-hero-inner{grid-template-columns:1fr;gap:2.6rem;align-items:start}
  .cs3-plate,.cs3-pane{aspect-ratio:4/3;margin-bottom:-3rem}
  .cs3-idx{margin-bottom:1.6rem}
  .cs3-title{margin-bottom:1.6rem}
  .cs3-rail{margin-bottom:2.4rem}
  .cs3-rail div{
    border-right:0;padding-right:0;margin-right:0;
    width:100%;padding-bottom:.85rem;margin-bottom:.85rem;border-bottom:1px solid var(--hair);
  }
  .cs3-rail div:last-child{border-bottom:0;padding-bottom:0;margin-bottom:0}
  .cs3-spec{padding:5.5rem 6vw 3rem}
  .cs3-sched div{grid-template-columns:1fr;gap:.35rem}
  .cs3-read{padding:3.6rem 6vw}
  .cs3-plates-inner{grid-template-columns:1fr}
  .cs3-plates figure,.cs3-plates figure.wide{aspect-ratio:4/3;grid-column:auto}
  .cs3-next-inner{align-items:flex-start}
}

/* ============ QUALITY FLOOR ============ */
.cs3 a:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
@media(prefers-reduced-motion:reduce){
  .cs3-plates img,.cs3-next-t,.cs3-next-t span,.cs3-btn,.cs3-btn-light{transition:none}
  .cs3-plates figure:hover img{transform:none}
  .cs3-next a.cs3-next-link:hover .cs3-next-t span{transform:none}
}