/* ============================================================
   differentiated.in
   Consulting practice — Anub Sinha.

   Design system: cool stone paper, near-black ink, a ledger
   green that means "inside the boundary" and a rust that means
   "leaving it". Those two colors carry the whole argument, so
   they are used with discipline: green for what you own, rust
   only for what escapes.

   Family-resemblant to anubsinha.com and the Applied books
   (Spectral / Inter / Plex Mono, light + dark), but cooler and
   more institutional. This is a practice, not a library.
   ============================================================ */

/* ----------------------------- TOKENS ----------------------------- */
:root{
  --bg:#f4f4f1; --surface:#fbfbf9; --surface-2:#eaebe6;
  --ink:#15171a; --muted:#5c6165; --faint:#8b8f93; --border:#dfe0da;

  /* inside the boundary */
  --accent:#1d5c47;
  --accent-soft:rgba(29,92,71,.06);
  --accent-line:rgba(29,92,71,.22);
  /* leaving the boundary — used sparingly, and only for that */
  --leak:#a4442c;
  --leak-soft:rgba(164,68,44,.07);
  --leak-line:rgba(164,68,44,.28);

  --serif:"Spectral","Source Serif 4",Georgia,"Iowan Old Style","Palatino Linotype",serif;
  --sans:"Inter",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --mono:"IBM Plex Mono","SF Mono","JetBrains Mono",ui-monospace,Menlo,monospace;

  --measure:64ch; --page:1040px;
}
[data-theme="dark"]{
  --bg:#0f1113; --surface:#16191c; --surface-2:#1e2226;
  --ink:#e8e9e5; --muted:#99a0a5; --faint:#757b80; --border:#292e33;

  --accent:#6cbf9b;
  --accent-soft:rgba(108,191,155,.09);
  --accent-line:rgba(108,191,155,.24);
  --leak:#e08163;
  --leak-soft:rgba(224,129,99,.09);
  --leak-line:rgba(224,129,99,.30);
}

/* ----------------------------- BASE ----------------------------- */
*{box-sizing:border-box}
html{font-size:19px; scroll-behavior:smooth; -webkit-text-size-adjust:100%}
@media (max-width:900px){ html{font-size:17.5px} }
body{
  margin:0; background:var(--bg); color:var(--ink);
  font-family:var(--serif); font-weight:400; line-height:1.7;
  font-feature-settings:"onum" 1,"pnum" 1;
  -webkit-font-smoothing:antialiased; text-rendering:optimizeLegibility;
  transition:background .25s ease, color .25s ease;
}
::selection{ background:var(--accent-soft); }
a{color:var(--accent); text-decoration-thickness:1px; text-underline-offset:3px; text-decoration-color:var(--accent-line);}
a:hover{text-decoration-color:var(--accent);}
strong{font-weight:600;} .muted{color:var(--muted);}
h1,h2,h3,h4{font-family:var(--serif); font-weight:600; letter-spacing:-.015em;}
p{margin:1rem 0; max-width:var(--measure);}

/* numerals that line up in tables and stat blocks */
.mono,.stat-n,.phase-n{font-feature-settings:"lnum" 1,"tnum" 1;}

/* ----------------------------- CHROME ----------------------------- */
.skip{position:absolute; left:-999px; top:0; background:var(--accent); color:#fff; padding:10px 16px;
  border-radius:0 0 8px 0; z-index:200; font-family:var(--sans); font-weight:600;}
.skip:focus{left:0;}
#progress{position:fixed; top:0; left:0; height:2px; width:0%; background:var(--accent); z-index:120; transition:width .08s linear;}

.topbar{position:fixed; top:0; left:0; right:0; z-index:130; display:flex; align-items:center;
  justify-content:space-between; gap:16px; padding:12px max(18px,4vw);
  background:color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter:saturate(140%) blur(9px);
  border-bottom:1px solid transparent; transition:border-color .25s, background .25s;}
.topbar.stuck{border-bottom-color:var(--border);}
.wordmark{display:inline-flex; align-items:center; gap:9px; text-decoration:none; color:var(--ink);
  font-family:var(--sans); font-weight:600; font-size:.8rem; letter-spacing:.02em;}
.wordmark .glyph{width:17px; height:17px; flex:0 0 auto; color:var(--accent);}
.wordmark:hover{color:var(--accent);}
.navlinks{display:flex; align-items:center; gap:22px;}
.navlinks a{font-family:var(--sans); font-size:.78rem; font-weight:500; color:var(--muted); text-decoration:none;}
.navlinks a:hover{color:var(--accent);}
@media (max-width:760px){ .navlinks a:not(.nav-cta){display:none;} }
.nav-cta{border:1px solid var(--border); border-radius:999px; padding:7px 15px; color:var(--ink)!important; white-space:nowrap;}
.nav-cta:hover{border-color:var(--accent); color:var(--accent)!important;}
.cta-short{display:none;}
.tbtn{font-family:var(--sans); font-size:.72rem; font-weight:500; color:var(--muted);
  background:none; border:none; cursor:pointer; padding:6px 2px; display:inline-flex; align-items:center; gap:6px;}
.tbtn:hover{color:var(--accent);}
.tbtn .dot{width:7px; height:7px; border-radius:50%; background:var(--accent); display:inline-block;}

/* On a phone the bar has room for the name and one action. The theme
   toggle goes, since the system preference is already honoured. */
@media (max-width:560px){
  .topbar{padding:10px 18px;}
  .wordmark{font-size:.7rem; white-space:nowrap; gap:7px;}
  .wordmark .glyph{width:15px; height:15px;}
  .tbtn{display:none;}
  .navlinks{gap:10px;}
  .nav-cta{font-size:.72rem; padding:7px 14px;}
  .cta-long{display:none;} .cta-short{display:inline;}
}

/* ----------------------------- LAYOUT ----------------------------- */
main{max-width:var(--page); margin:0 auto; padding:0 max(20px,6vw) 40px;}
section{margin-top:104px; scroll-margin-top:70px;}
.eyebrow{font-family:var(--sans); font-size:.7rem; font-weight:600; text-transform:uppercase;
  letter-spacing:.18em; color:var(--accent); margin:0 0 16px;}
.sec-head{display:flex; align-items:baseline; gap:14px; margin-bottom:10px; flex-wrap:wrap;}
.sec-head h2{margin:0; font-size:clamp(1.55rem,3.4vw,2rem); line-height:1.15;}
.sec-head .count{font-family:var(--sans); font-size:.68rem; font-weight:600; letter-spacing:.12em;
  text-transform:uppercase; color:var(--faint);}
.sec-intro{color:var(--muted); margin:0 0 34px; font-size:1.03rem; max-width:58ch;}
.rule{border:none; border-top:1px solid var(--border); margin:0 0 30px;}

/* ----------------------------- HERO ----------------------------- */
.hero{padding:132px 0 8px;}
.hero h1{font-size:clamp(2.3rem,6.2vw,3.9rem); line-height:1.03; letter-spacing:-.025em; margin:0 0 24px; max-width:19ch;}
.hero h1 .em{color:var(--accent); font-style:italic;}
.hero .lede{font-size:1.2rem; line-height:1.58; max-width:52ch; color:var(--ink); margin:0 0 18px;}
.hero .sub{font-family:var(--sans); font-size:.95rem; line-height:1.62; color:var(--muted); max-width:54ch; margin:0 0 34px;}
.cta-row{display:flex; flex-wrap:wrap; gap:12px; align-items:center;}
.btn{display:inline-flex; align-items:center; gap:9px; font-family:var(--sans); font-size:.86rem; font-weight:600;
  text-decoration:none; border-radius:999px; padding:12px 22px; border:1px solid var(--accent);
  background:var(--accent); color:var(--bg); transition:transform .15s, opacity .15s, box-shadow .15s;}
.btn:hover{transform:translateY(-1px); box-shadow:0 10px 24px -14px var(--accent);}
.btn .arrow{transition:transform .15s;} .btn:hover .arrow{transform:translateX(3px);}
.btn.ghost{background:none; color:var(--ink); border-color:var(--border);}
.btn.ghost:hover{border-color:var(--accent); color:var(--accent); box-shadow:none;}

/* the hero's quiet credibility line */
.hero-note{font-family:var(--sans); font-size:.78rem; color:var(--faint); margin-top:26px; letter-spacing:.01em;}
.hero-note strong{color:var(--muted); font-weight:600;}

/* ----------------------------- THE ARGUMENT (three beats) ----------------------------- */
.beats{display:grid; grid-template-columns:repeat(3,1fr); gap:1px; background:var(--border);
  border:1px solid var(--border); border-radius:12px; overflow:hidden;}
@media (max-width:820px){ .beats{grid-template-columns:1fr;} }
.beat{background:var(--surface); padding:30px 26px 32px;}
.beat .n{font-family:var(--mono); font-size:.7rem; font-weight:500; color:var(--accent); letter-spacing:.1em; display:block; margin-bottom:14px;}
.beat h3{font-size:1.18rem; line-height:1.3; margin:0 0 10px;}
.beat p{font-size:.94rem; color:var(--muted); margin:0; max-width:none; line-height:1.65;}
.beat.warn .n{color:var(--leak);}
.beat.warn{background:linear-gradient(180deg, var(--leak-soft), transparent 60%), var(--surface);}

/* ----------------------------- BOUNDARY DIAGRAM ----------------------------- */
.diagram{display:grid; grid-template-columns:1fr 1fr; gap:20px; margin-top:34px;}
@media (max-width:820px){ .diagram{grid-template-columns:1fr;} }
.panel{background:var(--surface); border:1px solid var(--border); border-radius:12px; padding:22px 22px 18px;}
.panel.owned{border-color:var(--accent-line);}
.panel h4{font-family:var(--sans); font-size:.72rem; font-weight:600; text-transform:uppercase;
  letter-spacing:.14em; margin:0 0 4px; color:var(--leak);}
.panel.owned h4{color:var(--accent);}
.panel .cap{font-size:.9rem; color:var(--muted); margin:0 0 16px; max-width:none; line-height:1.55;}
.panel svg{width:100%; height:auto; display:block;}
.d-label{font-family:var(--sans); font-size:8.5px; font-weight:600; letter-spacing:.02em; fill:var(--muted);}
.d-label-i{font-family:var(--sans); font-size:7.5px; font-weight:500; fill:var(--faint);}
.d-box{fill:var(--surface-2); stroke:var(--border); stroke-width:1;}
.d-bound{fill:none; stroke:var(--faint); stroke-width:1.2; stroke-dasharray:5 4;}
.d-bound-solid{fill:none; stroke:var(--accent); stroke-width:1.4;}
.d-flow{fill:none; stroke:var(--leak); stroke-width:1.5; stroke-dasharray:4 4;}
.d-flow-in{fill:none; stroke:var(--accent); stroke-width:1.5;}
.d-node{fill:var(--surface); stroke:var(--faint); stroke-width:1;}
.d-node-a{fill:var(--accent-soft); stroke:var(--accent); stroke-width:1.2;}
.d-node-l{fill:var(--leak-soft); stroke:var(--leak); stroke-width:1.2;}
@media (prefers-reduced-motion: no-preference){
  .d-flow{animation:drift 1.6s linear infinite;}
  .d-flow-in{stroke-dasharray:4 4; animation:drift 2.6s linear infinite reverse;}
}
@keyframes drift{ to{ stroke-dashoffset:-16; } }

/* ----------------------------- PROOF / STATS ----------------------------- */
.proof{background:var(--surface); border:1px solid var(--border); border-radius:14px; padding:34px 32px;}
.stats{display:grid; grid-template-columns:repeat(3,1fr); gap:26px; margin:0 0 26px;}
@media (max-width:720px){ .stats{grid-template-columns:1fr; gap:20px;} }
.stat{border-left:2px solid var(--accent-line); padding-left:18px;}
.stat-n{font-family:var(--serif); font-weight:600; font-size:clamp(1.9rem,4.6vw,2.5rem); line-height:1;
  letter-spacing:-.02em; color:var(--accent); display:block;}
.stat-l{font-family:var(--sans); font-size:.8rem; font-weight:500; color:var(--muted); margin-top:9px; display:block; line-height:1.45;}
.proof p{font-size:.98rem; color:var(--muted); max-width:64ch;}
.proof .src{font-family:var(--sans); font-size:.76rem; color:var(--faint); margin:18px 0 0;}
.proof .src a{color:var(--faint); text-decoration-color:var(--border);}
.proof .src a:hover{color:var(--accent);}

/* pull quote */
.pull{margin:34px 0 0; padding:0 0 0 22px; border-left:3px solid var(--accent-line);
  font-size:1.12rem; line-height:1.55; font-style:italic; color:var(--ink); max-width:56ch;}
.pull cite{display:block; font-style:normal; font-family:var(--sans); font-size:.76rem;
  color:var(--faint); margin-top:12px; letter-spacing:.02em;}

/* ----------------------------- SERVICES ----------------------------- */
.services{display:grid; grid-template-columns:repeat(2,1fr); gap:16px;}
@media (max-width:820px){ .services{grid-template-columns:1fr;} }
.svc{background:var(--surface); border:1px solid var(--border); border-radius:12px; padding:26px 26px 24px;
  display:flex; flex-direction:column; transition:border-color .15s, transform .15s;}
.svc:hover{border-color:var(--accent-line); transform:translateY(-2px);}
.svc.lead{grid-column:1 / -1; border-color:var(--accent-line);
  background:linear-gradient(180deg, var(--accent-soft), transparent 55%), var(--surface);}
.svc-top{display:flex; align-items:baseline; justify-content:space-between; gap:14px; margin-bottom:9px;}
.svc h3{font-size:1.2rem; margin:0;}
.svc .tag{font-family:var(--sans); font-size:.63rem; font-weight:600; text-transform:uppercase; letter-spacing:.1em;
  color:var(--accent); border:1px solid var(--accent-line); border-radius:999px; padding:3px 10px; white-space:nowrap;}
.svc p{font-size:.94rem; color:var(--muted); margin:0 0 16px; max-width:none; line-height:1.62;}
.svc ul{list-style:none; padding:0; margin:0 0 4px; font-family:var(--sans); font-size:.84rem; color:var(--muted);}
.svc li{padding:6px 0 6px 20px; position:relative; line-height:1.5;}
.svc li::before{content:""; position:absolute; left:2px; top:1.02em; width:7px; height:1.5px; background:var(--accent);}
.svc .deliv{margin-top:auto; padding-top:16px; font-family:var(--sans); font-size:.78rem; color:var(--faint);
  border-top:1px solid var(--border);}
.svc .deliv strong{color:var(--muted); font-weight:600;}
@media (min-width:821px){ .svc.lead .svc-body{display:grid; grid-template-columns:1.15fr 1fr; gap:30px; align-items:start;} }
.svc.lead .svc-body > p{margin-bottom:0;}

/* ----------------------------- THE LOOP (method) ----------------------------- */
.loop{display:grid; grid-template-columns:repeat(4,1fr); gap:0;}
@media (max-width:900px){ .loop{grid-template-columns:repeat(2,1fr); gap:26px 0;} }
@media (max-width:520px){ .loop{grid-template-columns:1fr; gap:22px;} }
.phase{padding:0 22px 0 0; position:relative;}
.phase::after{content:""; position:absolute; top:9px; right:11px; width:8px; height:8px;
  border-top:1.4px solid var(--accent-line); border-right:1.4px solid var(--accent-line); transform:rotate(45deg);}
.phase:last-child::after{display:none;}
@media (max-width:900px){ .phase:nth-child(2n)::after{display:none;} }
@media (max-width:520px){ .phase::after{display:none;} }
.phase-n{font-family:var(--mono); font-size:.7rem; color:var(--accent); letter-spacing:.1em; display:block; margin-bottom:12px;}
.phase h3{font-size:1.04rem; margin:0 0 8px;}
.phase p{font-size:.88rem; color:var(--muted); margin:0; max-width:none; line-height:1.6;}
.loop-note{font-family:var(--sans); font-size:.84rem; color:var(--muted); margin-top:34px;
  padding:16px 20px; background:var(--accent-soft); border-radius:10px; border-left:2px solid var(--accent); max-width:none;}

/* ----------------------------- FIT (for / not for) ----------------------------- */
.fit{display:grid; grid-template-columns:1fr 1fr; gap:16px;}
@media (max-width:760px){ .fit{grid-template-columns:1fr;} }
.fit-col{background:var(--surface); border:1px solid var(--border); border-radius:12px; padding:24px 26px;}
.fit-col h3{font-family:var(--sans); font-size:.74rem; font-weight:600; text-transform:uppercase;
  letter-spacing:.13em; margin:0 0 16px; color:var(--accent);}
.fit-col.no h3{color:var(--faint);}
.fit-col ul{list-style:none; padding:0; margin:0;}
.fit-col li{font-size:.94rem; color:var(--muted); line-height:1.55; padding:9px 0 9px 24px; position:relative;
  border-bottom:1px solid var(--border);}
.fit-col li:last-child{border-bottom:none;}
.fit-col li::before{content:"✓"; position:absolute; left:0; top:9px; color:var(--accent); font-size:.86rem;}
.fit-col.no li::before{content:"×"; color:var(--faint); font-size:1rem; top:8px;}

/* ----------------------------- ABOUT ----------------------------- */
.about{display:grid; grid-template-columns:1.4fr 1fr; gap:44px; align-items:start;}
@media (max-width:820px){ .about{grid-template-columns:1fr; gap:28px;} }
.about p{font-size:1rem;}
.about-side{background:var(--surface); border:1px solid var(--border); border-radius:12px; padding:22px 24px;}
.about-side h3{font-family:var(--sans); font-size:.72rem; font-weight:600; text-transform:uppercase;
  letter-spacing:.13em; color:var(--faint); margin:0 0 14px;}
.about-side ul{list-style:none; padding:0; margin:0; font-family:var(--sans); font-size:.86rem;}
.about-side li{padding:8px 0; border-bottom:1px solid var(--border);}
.about-side li:last-child{border-bottom:none;}
.about-side a{text-decoration:none; display:flex; justify-content:space-between; gap:12px; color:var(--ink);}
.about-side a:hover{color:var(--accent);}
.about-side .host{font-family:var(--mono); font-size:.72rem; color:var(--faint);}

/* ----------------------------- CONTACT ----------------------------- */
.contact{background:var(--surface); border:1px solid var(--accent-line); border-radius:14px;
  padding:44px 38px; text-align:center;
  background-image:linear-gradient(180deg, var(--accent-soft), transparent 60%);}
.contact h2{font-size:clamp(1.6rem,4vw,2.2rem); margin:0 0 14px; letter-spacing:-.02em;}
.contact p{color:var(--muted); margin:0 auto 26px; max-width:50ch; font-size:1.02rem;}
.contact .cta-row{justify-content:center;}
.contact .fine{font-family:var(--sans); font-size:.76rem; color:var(--faint); margin-top:24px;}

/* ----------------------------- FOOTER ----------------------------- */
footer{max-width:var(--page); margin:96px auto 0; padding:26px max(20px,6vw) 46px;
  border-top:1px solid var(--border); font-family:var(--sans); font-size:.76rem; color:var(--faint);
  display:flex; justify-content:space-between; flex-wrap:wrap; gap:12px;}
footer a{color:var(--muted); text-decoration:none;} footer a:hover{color:var(--accent);}
footer .fl{display:flex; gap:18px; flex-wrap:wrap;}

/* ----------------------------- REVEAL -----------------------------
   Fails open. The hidden state is scoped to .js, which the pre-paint
   guard in <head> sets, so without JS (or if the script errors) every
   section renders normally instead of staying invisible. */
@media (prefers-reduced-motion: no-preference){
  .js .reveal{opacity:0; transform:translateY(12px); transition:opacity .5s ease, transform .5s ease;}
  .js .reveal.in{opacity:1; transform:none;}
}

/* focus visibility */
a:focus-visible, button:focus-visible{outline:2px solid var(--accent); outline-offset:3px; border-radius:4px;}

/* ----------------------------- REDUCED MOTION / PRINT ----------------------------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{animation-duration:.001ms!important; transition-duration:.001ms!important;}
}
@media print{
  .topbar,#progress,#toTop{display:none!important;}
  body{background:#fff; color:#000;}
  main{max-width:none; padding:0;}
  .svc,.beat,.panel,.fit-col{break-inside:avoid;}
  a{color:#000;}
}