/* ================= Paytm case study: page styles =================
   One system for the page. Phone mock-ups (hero phone below, flows in flows.css) are Paytm's UI and keep their own sizes.

   Type   13 · 15 · 17 · 21 · 28 · 48 · 80   (--t1 … --t7)
   Serif (Instrument Serif) only for h1 and h2. Everything else is Geist.
   Accent: Paytm sky (--brand), sparingly: quote rule, feature card stripe, tints. Never on headings, never as text colour.
   Radius 8 · 16 · 24                         (--r1 … --r3; nested = outer − padding)
   Space  8 · 16 · 24 · 40 · 64 · 104         (--s1 … --s6) */
:root{
  --t1:13px;--t2:15px;--t3:17px;--t4:21px;--t5:28px;--t6:clamp(36px,3.6vw,48px);--t7:clamp(48px,6vw,80px);
  --r1:8px;--r2:16px;--r3:24px;
  --s1:8px;--s2:16px;--s3:24px;--s4:40px;--s5:64px;--s6:104px;
  --serif:"Instrument Serif",Georgia,serif;--sans:"Geist",ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif;
  --ease:cubic-bezier(.16,1,.3,1);--gold:#FFD23F;
  --side-w:216px;--pad:clamp(16px,6vw,96px);

  --bg:#fff;--ink:#10141b;--ink-2:#2a303b;--muted:#5b6474;--faint:#6b7382;--line:rgba(16,20,27,.1);
  --accent:#1f6fd1;--brand:#00BAF2;--brand-tint:rgba(0,186,242,.08);--sketch:#2c43a8;--panel:#f4f4f6;--ann:#2f6fe0;--ann-ink:#10141b;--ann-dim:#5b6474;
  --pg-ink:var(--ink);--pg-muted:var(--muted);--pg-faint:var(--faint);--pg-line:var(--line);--pg-bg:var(--bg);
  --glass:rgba(255,255,255,.7);--glass-bd:rgba(255,255,255,.75);--glass-sh:0 8px 28px rgba(20,40,80,.12);
}
:root[data-sky="night"]{
  --bg:#070a12;--ink:#f4f6fa;--ink-2:#dfe3ea;--muted:#b9c0cd;--faint:#9ba4b4;--line:rgba(255,255,255,.12);
  --accent:#9fc3ff;--brand:#00BAF2;--brand-tint:rgba(0,186,242,.12);--sketch:#a9b9ff;--panel:#141824;--ann:#8db4ff;--ann-ink:#f4f6fa;--ann-dim:#c3cad6;
  --pg-ink:var(--ink);--pg-muted:var(--muted);--pg-faint:var(--faint);--pg-line:var(--line);--pg-bg:var(--bg);
  --glass:rgba(16,20,32,.7);--glass-bd:rgba(255,255,255,.12);--glass-sh:0 8px 28px rgba(0,0,0,.35);color-scheme:dark;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:var(--s3);background:var(--bg);transition:background-color 1s}
body{font:400 var(--t3)/1.6 var(--sans);background:var(--bg);color:var(--ink);-webkit-font-smoothing:antialiased;transition:background-color 1s,color 1s}
::selection{background:#cfe0f7;color:#10141b}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
a{color:inherit}
img{max-width:100%}
mark{background:none;color:var(--ink);font-weight:500}

/* ---------- sidebar ---------- */
.side{position:fixed;inset:0 auto 0 0;width:var(--side-w);padding:var(--s3) var(--s2);border-right:1px solid var(--line);display:flex;flex-direction:column;background:var(--bg);z-index:20;transition:transform .45s var(--ease)}
.side-top{display:flex;align-items:center;justify-content:space-between;padding-left:var(--s1)}
.back{display:inline-flex;align-items:center;gap:6px;font-size:var(--t2);font-weight:500;color:var(--ink);text-decoration:none;background:var(--panel);border-radius:999px;padding:6px 14px 6px 12px;transition:background .2s}
.back:hover{background:var(--line)}
.collapse{border:0;background:none;color:var(--faint);width:24px;height:24px;border-radius:var(--r1);display:grid;place-items:center;cursor:pointer}
.collapse:hover{color:var(--ink)}
.side .brand{margin-top:var(--s4);padding:0 var(--s1)}
.side .brand .t{font-size:var(--t2);font-weight:500}
.side .brand .s{font-size:var(--t1);color:var(--faint)}
.nav{margin-top:var(--s3);flex:1;overflow:auto}
.nav ol{list-style:none}
.nav a{display:flex;gap:var(--s1);align-items:baseline;padding:6px var(--s1);font-size:var(--t2);color:var(--muted);text-decoration:none;border-radius:var(--r1)}
.nav a i{font-style:normal;font-size:var(--t1);color:var(--faint);font-variant-numeric:tabular-nums}
.nav a:hover,.nav a.on{color:var(--ink)}
.nav a.on{font-weight:600;border-radius:0;box-shadow:inset 2px 0 0 var(--ink)}
.nav a.on i{color:var(--accent)}
.nav .docs{margin-top:var(--s3);padding-top:var(--s2);border-top:1px solid var(--line)}
.docs-tg{display:flex;align-items:center;justify-content:space-between;width:100%;border:0;background:none;font:inherit;font-size:var(--t2);color:var(--muted);padding:6px var(--s1);cursor:pointer;text-align:left}
.docs-tg:hover{color:var(--ink)}
.docs-tg svg{color:var(--faint);transition:transform .3s var(--ease)}
.docs-tg[aria-expanded="true"] svg{transform:rotate(45deg)}
.docs-list{display:grid;grid-template-rows:0fr;transition:grid-template-rows .35s var(--ease)}
.docs-list>ol{overflow:hidden}
.docs-tg[aria-expanded="true"]+.docs-list{grid-template-rows:1fr}
.docs-list a{font-size:var(--t1);padding:4px var(--s1) 4px var(--s3)}
.reopen{position:fixed;top:var(--s2);left:var(--s2);z-index:19;height:40px;padding:0 12px;display:flex;align-items:center;gap:var(--s1);font:inherit;font-size:var(--t1);color:var(--ink);background:var(--glass);border:1px solid var(--glass-bd);border-radius:var(--r1);-webkit-backdrop-filter:blur(24px);backdrop-filter:blur(24px);cursor:pointer;opacity:0;pointer-events:none;transition:opacity .3s}
body.side-off .side{transform:translateX(-100%)}
body.side-off .reopen{opacity:1;pointer-events:auto}
body.side-off main{margin-left:0}

/* ---------- sections ---------- */
main{margin-left:var(--side-w);transition:margin .45s var(--ease)}
.sec{padding:var(--s6) var(--pad) var(--s5);border-top:1px solid var(--line)}
.sec:first-child{border-top:0}
.wrap{max-width:1120px}
h1{font:400 var(--t7)/1 var(--serif);letter-spacing:-.02em;text-wrap:balance}
h2{font:400 var(--t6)/1.05 var(--serif);letter-spacing:-.015em;max-width:20ch;text-wrap:balance}
h3{font-size:var(--t4);font-weight:600;line-height:1.3;letter-spacing:-.01em}
.lead{font-size:var(--t4);line-height:1.5;color:var(--ink-2);margin-top:var(--s3);max-width:34ch}
.body{color:var(--ink-2);margin-top:var(--s3);max-width:62ch}
.note{margin-top:var(--s3);max-width:62ch;font-size:var(--t2);color:var(--muted)}
.note b{font-weight:500;color:var(--ink)}
.part{margin-top:var(--s5)}
/* tags: stages, user types, model labels */
.tag{display:inline-block;vertical-align:middle;font:500 var(--t1)/1.6 var(--sans);letter-spacing:0;color:var(--ink-2);background:var(--panel);border:1px solid transparent;border-radius:999px;padding:1px 10px;white-space:nowrap}
.tag.ghost{background:none;border:1px dashed var(--faint);color:var(--muted)}
.tag+.tag{margin-left:6px}
.part .tag{margin-left:var(--s1)}
.part-d{margin-top:var(--s1);max-width:62ch;color:var(--ink-2)}

/* hero */
.hero{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,.9fr);gap:var(--s5);align-items:center}
.meta-row{margin-top:var(--s4);display:flex;flex-wrap:wrap;gap:var(--s2) var(--s4);padding-top:var(--s2);border-top:1px solid var(--line)}
.meta-row dt{font-size:var(--t1);color:var(--faint)}
.meta-row dd{font-size:var(--t2);color:var(--ink-2)}
.disclaim{margin-top:var(--s2);font-size:var(--t1);color:var(--faint)}

/* two columns of plain text */
.cols{margin-top:var(--s4);display:grid;grid-template-columns:1fr 1fr;gap:var(--s2);max-width:980px}
.cols>div{position:relative;background:var(--bg);border:1px solid var(--line);border-radius:var(--r3);padding:var(--s3) var(--s4)}
.cols.one{grid-template-columns:1fr;margin-top:var(--s2)}
.cols h3{font-size:var(--t2);color:var(--muted);font-weight:500}
.cols p{margin-top:var(--s1);color:var(--ink)}

/* stages: three columns, a rule on top; the later one dashed */
.stages{list-style:none;margin-top:var(--s4);display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:var(--s4);max-width:1060px}
.stages li{border:1px solid var(--line);border-radius:var(--r3);padding:var(--s3)}
.stages li.later{border-style:dashed;border-color:var(--faint)}
.stages h3{margin-top:0}
.stages h3 .tag{margin-left:var(--s1)}
.stages h3 .tag+.tag{margin-left:6px}
/* a progression: arrow on the rule between stages */
.prog li{position:relative}
.prog li+li::before{content:"→";position:absolute;left:calc(-1 * var(--s4) / 2 - 9px);top:50%;margin-top:-12px;width:16px;text-align:center;font-size:var(--t2);color:var(--muted);background:var(--bg)}
.stages p{margin-top:var(--s1);font-size:var(--t2);color:var(--muted)}

/* questions: one row each, question left, answer right */
.qa{list-style:none;margin-top:var(--s4);max-width:980px;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:var(--s2)}
.qa li{border:1px solid var(--line);border-radius:var(--r3);padding:var(--s3)}
.qa .tag{margin-bottom:var(--s2)}
.qa h3{font-size:var(--t4)}
.qa p{margin-top:var(--s1);font-size:var(--t2);color:var(--muted)}

/* the loop: one line, arrows between */
.loop{list-style:none;margin-top:var(--s5);display:flex;flex-wrap:wrap;align-items:baseline;gap:var(--s1) 0;font-size:var(--t4);font-weight:500}
.loop li{display:flex;flex-direction:column}
.loop li+li::before{content:"→";position:absolute;margin-left:-38px;color:var(--faint);font-weight:400}
.loop li+li{position:relative;margin-left:52px}
.loop li:last-child::after{content:"↺";position:absolute;right:-30px;top:0;color:var(--faint);font-weight:400}
.loop .tag{align-self:flex-start;margin-top:6px}

.pull{margin-top:var(--s4);max-width:62ch;font:400 var(--t3)/1.6 var(--sans);color:var(--ink);padding-left:var(--s2);border-left:4px solid var(--brand);border-radius:0}

/* outcomes table: rules only */
.tbl{margin-top:var(--s4);width:100%;max-width:980px;border-collapse:collapse;font-size:var(--t2)}
.tbl th{text-align:left;font-size:var(--t1);font-weight:400;color:var(--faint);padding:0 var(--s2) var(--s1) 0;border-bottom:1px solid var(--ink)}
.tbl td{padding:12px var(--s2) 12px 0;border-bottom:1px solid var(--line);color:var(--ink-2);vertical-align:top}
.tbl td:first-child{color:var(--ink);font-weight:500}
.tbl td:last-child{color:var(--muted);white-space:nowrap}

/* reflections */
.ref{list-style:none;margin-top:var(--s4);max-width:820px;counter-reset:r}
.ref li{counter-increment:r;position:relative;padding:var(--s3) 0 var(--s3) var(--s4);border-top:1px solid var(--line)}
.ref li::before{content:counter(r,decimal-leading-zero);position:absolute;left:0;top:calc(var(--s3) + 4px);font-size:var(--t1);color:var(--faint)}
.ref p{margin-top:var(--s1);color:var(--ink-2)}

/* status chips in the outcomes table */
.chip{display:inline-block;font-size:var(--t1);font-weight:500;border-radius:999px;padding:1px 10px}
.chip.up{background:rgba(7,148,85,.12);color:#067647}
.chip.hold{background:var(--panel);color:var(--ink-2)}
.chip.watch{background:rgba(220,104,3,.12);color:#b54708}
:root[data-sky="night"] .chip.up{color:#5ee0a0}
:root[data-sky="night"] .chip.watch{color:#fdb022}

/* feature card: a point on the left, a UI fragment bleeding off the bottom right */
.feature{position:relative;margin-top:var(--s4);max-width:980px;min-height:280px;border:1px solid var(--line);border-radius:var(--r3);overflow:hidden;display:grid;grid-template-columns:minmax(0,1.4fr) minmax(0,.9fr);gap:var(--s4)}
.feature-t{position:relative;padding:var(--s5) 0 var(--s5) var(--s5)}
.feature-t::before{content:"";position:absolute;left:-1px;top:calc(var(--s5) + 4px);width:4px;height:52px;border-radius:0 2px 2px 0;background:var(--brand)}
.feature-t h3{font-size:var(--t4)}
.feature-t p{margin-top:var(--s2);max-width:60ch;color:var(--muted)}
.frag{zoom:.85;align-self:end;margin:var(--s5) calc(-1 * var(--s3)) -1px 0;background:var(--bg);border:1px solid var(--line);border-bottom:0;border-radius:var(--r2) var(--r2) 0 0;box-shadow:0 24px 48px -32px rgba(16,20,27,.35);padding-bottom:var(--s3)}
.frag-bar{display:flex;align-items:center;gap:6px;padding:12px var(--s2);border-bottom:1px solid var(--line);font-size:var(--t1);color:var(--muted)}
.frag-bar i{width:9px;height:9px;border-radius:50%;background:var(--line)}
.frag-bar span{margin-left:var(--s1)}
.frag-row{display:flex;align-items:center;gap:12px;margin:var(--s2) var(--s2) 0;padding:12px;border:1px solid var(--line);border-radius:12px}
.frag-row img{width:40px;height:40px;border-radius:var(--r1);object-fit:cover;flex:none}
.frag-row>div{flex:1;min-width:0}
.frag-row b{display:block;font-size:var(--t2);font-weight:600}
.frag-row span{font-size:var(--t1);color:var(--muted)}
.frag-row em{font-style:normal;font-size:var(--t1);font-weight:500;border-radius:999px;padding:2px 10px;white-space:nowrap}
.frag-row em.ok{background:rgba(7,148,85,.12);color:#067647}
.frag-row em.wait{background:var(--brand-tint);color:var(--ink)}
.frag-prog{display:block;height:4px;margin-top:6px;border-radius:2px;background:var(--line);max-width:140px}
.frag-prog s{display:block;width:50%;height:100%;border-radius:2px;background:var(--brand)}
:root[data-sky="night"] .frag-row em.ok{color:#5ee0a0}

/* storyboard: sketch panels, three in view, more scroll sideways; captions in the sketch's ink */
.story{margin-top:var(--s4)}
.story-nav{display:flex;justify-content:flex-end;gap:var(--s1);margin-bottom:var(--s2);max-width:980px}
.story-nav button{width:36px;height:36px;border-radius:50%;border:1px solid var(--line);background:var(--bg);color:var(--ink);display:grid;place-items:center;cursor:pointer}
.story-nav button:hover{background:var(--panel)}
.story-nav button:disabled{opacity:.35;cursor:default}
/* the strip runs to the screen's right edge with fixed-width panels, so the last visible one is always cut: a built-in scroll cue */
.pics{display:flex;gap:var(--s3);overflow-x:auto;scroll-snap-type:x mandatory;scrollbar-width:none;padding-bottom:var(--s1);margin-right:calc(-1 * var(--pad));padding-right:var(--pad)}
.pics::-webkit-scrollbar{display:none}
.pics figure{flex:0 0 clamp(250px,23vw,330px);scroll-snap-align:start}
.pics figure img{display:block;width:100%;height:auto;aspect-ratio:487/418;object-fit:fill;border-radius:var(--r1);background:#fff}
/* panels are cut inside the sketch frame and padded to one size; the frame is drawn here so all six match */
.pics.wide figure{flex-basis:clamp(300px,30vw,400px)}
.pics.wide figure img{aspect-ratio:596/409;object-fit:cover;border:2px solid #3a51b8;border-radius:3px;background:#fff}
/* decision cards in the same strip */
.pics.decks{gap:var(--s2);align-items:stretch}
.pics.decks .feature{flex:0 0 min(860px,82vw);margin-top:0;scroll-snap-align:start}
.pics.decks .feature-t{padding:var(--s4) 0 var(--s4) var(--s4)}
.pics.decks .feature-t::before{top:calc(var(--s4) + 4px)}
.pics.decks .frag{margin-top:var(--s4)}
.frag-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin:var(--s2) var(--s2) 0}
.frag-grid span{display:grid;place-items:end center;height:58px;padding-bottom:6px;border:1px solid var(--line);border-radius:10px;font-size:11px;color:var(--muted);background:linear-gradient(var(--panel) 0 50%,transparent 50%)}
.pics figcaption{margin-top:12px;font:400 var(--t2)/1.45 "Shantell Sans",var(--sans);color:var(--sketch)}
.pics figcaption b{display:block;font-weight:500;margin-bottom:2px}

/* ---------- research & process (accordion list) ---------- */
.acc{margin-top:var(--s4);max-width:1060px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:var(--s2);align-items:start}
.acc details{border:1px solid var(--line);border-radius:var(--r3);padding:0 var(--s3);transition:border-color .2s}
.acc details:hover{border-color:var(--faint)}
.acc details[open]{grid-column:1/-1;background:var(--panel);border-color:transparent}
summary{list-style:none;cursor:pointer;display:grid;grid-template-columns:40px 1fr 20px;gap:var(--s2);align-items:baseline;padding:var(--s3) 0}
summary::-webkit-details-marker{display:none}
summary .num{font-size:var(--t1);color:var(--faint);font-variant-numeric:tabular-nums}
summary .tt{font-size:var(--t3);font-weight:500}
summary .ts{display:block;font-size:var(--t2);color:var(--muted)}
summary svg{color:var(--faint);transition:transform .3s var(--ease)}
details[open] summary svg{transform:rotate(45deg)}
summary:hover .tt{color:var(--accent)}
.dc{padding:0 0 var(--s3) 56px;font-size:var(--t2);color:var(--ink-2)}
.dc>p{max-width:62ch}
.dc h4{font-size:var(--t1);font-weight:500;color:var(--faint);margin:var(--s3) 0 var(--s1)}
.dc h4:first-child{margin-top:0}
.dc .tbl{margin-top:0}
.dc table{width:100%;border-collapse:collapse}
.dc td,.dc th{text-align:left;padding:10px var(--s2) 10px 0;border-bottom:1px solid var(--line);vertical-align:top;font-weight:400}
.dc th{font-size:var(--t1);color:var(--faint);border-bottom-color:var(--ink)}
.dc td:last-child{white-space:normal;color:var(--ink-2)}
.acc details{min-width:0}
.dc td:first-child{color:var(--ink);font-weight:500;white-space:nowrap}
.dc .tbl{border:0}
.dir{color:var(--muted)}
.qbox{font-size:var(--t3);font-weight:500;color:var(--ink);max-width:62ch;padding-left:var(--s2);border-left:4px solid var(--brand);border-radius:0}
.people,.clusters,.jt,.cpt,.split{display:grid;gap:var(--s3) var(--s4)}
.people{grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:var(--s2)}
.clusters,.split{grid-template-columns:1fr 1fr}
.jt,.cpt{grid-template-columns:repeat(3,minmax(0,1fr))}
.pp,.cl,.jt>div,.cpt>div,.split>div{background:var(--bg);border-radius:var(--r2);padding:var(--s2)}
.pp .top{display:flex;align-items:center;gap:var(--s1)}
.pp .av{width:28px;height:28px;border-radius:50%;display:grid;place-items:center;font-size:var(--t1);font-weight:600;color:#fff;flex:none}
.pp .n{font-weight:500;color:var(--ink)}
.pp .r,.pp .app{font-size:var(--t1);color:var(--muted)}
.pp .app{display:block;margin-top:var(--s1)}
.pp p{margin-top:4px}
.cl h5,.cpt h5{font-size:var(--t2);font-weight:500;color:var(--ink)}
.cl ul{list-style:none;margin-top:var(--s1)}
.cl li{padding:4px 0;color:var(--ink-2)}
.cl .so{margin-top:var(--s1);color:var(--muted)}
.jt b,.split b,.cpt .st{display:block;font-size:var(--t1);font-weight:500;color:var(--muted)}
.jt p,.cpt p{margin-top:4px}
.pchips{display:flex;flex-wrap:wrap;gap:var(--s1)}
.pchips span{border:1px solid var(--line);border-radius:var(--r1);padding:4px 10px;font-size:var(--t1);color:var(--ink-2)}
.qs{padding-left:var(--s3);max-width:62ch}
.qs li{padding:4px 0}

footer.pfoot{display:flex;justify-content:space-between;gap:var(--s2);flex-wrap:wrap;padding:var(--s4) var(--pad) var(--s5);border-top:1px solid var(--line);font-size:var(--t1);color:var(--muted)}

/* day / night switch, top right */
.pdock{position:fixed;top:calc(env(safe-area-inset-top,0px) + var(--s2));right:max(var(--s2),env(safe-area-inset-right,0px));z-index:40;display:flex}
.pdock .glass{height:44px;padding:0 var(--s1);border-radius:var(--r2);background:var(--glass);border:1px solid var(--glass-bd);box-shadow:var(--glass-sh);-webkit-backdrop-filter:blur(24px) saturate(170%);backdrop-filter:blur(24px) saturate(170%);display:flex;align-items:center}
.pdn{position:relative;width:52px;height:28px;border:0;border-radius:999px;cursor:pointer;padding:0;overflow:hidden;background:linear-gradient(180deg,#6cc4f7,#2f8fe0);box-shadow:inset 0 1px 3px rgba(0,0,0,.3);transition:background .8s}
.pdn i{position:absolute;top:3px;left:3px;width:22px;height:22px;border-radius:50%;transition:transform .8s cubic-bezier(.22,.8,.24,1);background:radial-gradient(circle at 40% 35%,#fffbe0,#ffd23f 60%,#ffae1a);box-shadow:0 0 12px rgba(255,214,90,.9)}
.pdn[aria-checked="false"]{background:linear-gradient(180deg,#141a3a,#28305f)}
.pdn[aria-checked="false"] i{transform:translateX(24px);background:radial-gradient(circle at 40% 35%,#fff,#d6dae8 70%);box-shadow:0 0 12px rgba(200,210,255,.6)}

/* ---------- hero phone (Paytm UI mock-up, own sizes) ---------- */
.hero-stage{position:relative;display:flex;justify-content:center;padding:24px 0}

.ph{position:relative;width:300px;height:614px;border-radius:52px;padding:4px;flex:none;
  background:linear-gradient(145deg,#f4f5f7 0%,#c9ccd2 18%,#eef0f2 40%,#a9adb4 62%,#e7e9ec 82%,#bfc3c9 100%);
  box-shadow:0 0 0 1px #9ea2a8 inset,0 40px 70px -26px rgba(20,28,46,.45),0 12px 26px -14px rgba(20,28,46,.3)}
.ph .sb{position:absolute;width:4px;border-radius:2px;background:linear-gradient(90deg,#8d9197,#e2e4e7 60%,#a3a7ad)}
.ph .l1{left:-3px;top:112px;height:28px}.ph .l2{left:-3px;top:160px;height:52px}.ph .l3{left:-3px;top:224px;height:52px}.ph .r1{right:-3px;top:178px;height:84px}
.ph .bz{height:100%;border-radius:48px;background:#050505;padding:10px}
.ph .sc{position:relative;height:100%;border-radius:39px;overflow:hidden;background:radial-gradient(120% 60% at 50% 40%,#232c42 0%,#0f1523 70%);color:#fff;font-family:Inter,sans-serif;isolation:isolate}
.ph .sc::before{content:"";position:absolute;inset:0;background:radial-gradient(70% 45% at 50% 30%,#2b6cf0 0%,transparent 70%),linear-gradient(180deg,#0b47c8,#082f8a);opacity:0;transition:opacity .6s var(--ease);z-index:-1}
.ph .rays{position:absolute;left:50%;top:26%;width:860px;height:860px;margin:-430px 0 0 -430px;border-radius:50%;z-index:-1;opacity:0;transition:opacity .8s;
  background:repeating-conic-gradient(from 0deg,rgba(255,255,255,.08) 0 6deg,transparent 6deg 15deg);
  -webkit-mask:radial-gradient(circle,#000 0 28%,transparent 60%);mask:radial-gradient(circle,#000 0 28%,transparent 60%);animation:rot 50s linear infinite}
@keyframes rot{to{transform:rotate(360deg)}}
.ph .isl{position:absolute;top:10px;left:50%;transform:translateX(-50%);width:92px;height:27px;border-radius:18px;background:#000;z-index:8}
.ph .st{position:absolute;top:0;left:0;right:0;height:44px;display:flex;align-items:center;justify-content:space-between;padding:4px 24px 0 28px;font-weight:600;font-size:13px;z-index:7}
.ph .st svg{fill:currentColor}
.ph .hd{position:absolute;top:74px;left:0;right:0;text-align:center;padding:0 24px;transition:opacity .4s,transform .5s var(--ease)}
.ph .hd b{display:block;font-size:18px;font-weight:700;letter-spacing:-.015em}
.ph .hd span{display:block;font-size:10.5px;color:#b9c1d3;margin-top:5px}
.fan{position:absolute;left:50%;top:146px;width:0;height:300px}
.fc{position:absolute;left:-62px;top:20px;width:124px;background:#fff;border-radius:12px;padding:5px;color:#141a26;transform-origin:50% 140%;
  transition:transform .8s var(--ease),opacity .5s,box-shadow .35s,filter .4s;box-shadow:0 14px 28px -12px rgba(0,0,0,.6);opacity:0;transform:translateY(320px) rotate(0)}
.fc .im{height:86px;border-radius:8px;overflow:hidden;background:#fbfbfb;position:relative}
.fc .im img{width:100%;height:100%;object-fit:cover;display:block}
.fc .im img.ct{object-fit:contain}
.fc .im img.lg{position:absolute;top:5px;left:5px;width:20px;height:20px;border-radius:50%;object-fit:cover}
.fc .b{font-size:8px;color:#475467;margin-top:6px;padding:0 2px}
.fc .o{font-size:10px;font-weight:600;line-height:1.25;margin-top:2px;padding:0 2px 4px}
.fc .btn{background:#0c0c0c;color:#fff;font-size:8.5px;font-weight:700;text-align:center;border-radius:999px;padding:6px;margin-top:2px;transition:background .25s,color .25s}
.in .fc{opacity:1}
.in .fc:nth-child(1){transform:rotate(-12deg) translate(-70px,20px);transition-delay:.05s}
.in .fc:nth-child(2){transform:rotate(12deg) translate(70px,20px);transition-delay:.15s}
.in .fc:nth-child(3){transform:translateY(-6px);z-index:3;transition-delay:.25s}
.sel .fc:nth-child(3){transform:translateY(-16px) scale(1.06);box-shadow:0 0 0 2.5px var(--gold),0 20px 36px -12px rgba(0,0,0,.75);transition-delay:0s}
.sel .fc:nth-child(3) .btn{background:var(--gold);color:#3a2a00}
.sel .fc:nth-child(1),.sel .fc:nth-child(2){opacity:.4;filter:saturate(.5);transition-delay:0s}
.ph .cta{position:absolute;left:14px;right:14px;bottom:26px;border-radius:12px;background:#2a3245;color:#8e97ab;text-align:center;font-size:12.5px;font-weight:700;padding:12px;transition:background .3s,color .3s,transform .15s}
.sel .cta,.won .cta{background:var(--gold);color:#3a2a00}
.ph .cta.press,.fc .btn.press{transform:scale(.95)}
.ph .sc.won::before,.won .rays{opacity:1}
.won .hd{opacity:0;transform:translateY(-12px)}
.won .fc:nth-child(1),.won .fc:nth-child(2){opacity:0;transform:translateY(340px)}
.won .fc:nth-child(3){transform:translateY(-82px) scale(.96);box-shadow:0 22px 40px -14px rgba(0,0,0,.55)}
.wtx{position:absolute;top:330px;left:0;right:0;text-align:center;padding:0 20px;opacity:0;transform:translateY(14px);transition:opacity .5s .25s,transform .7s .25s var(--ease)}
.won .wtx{opacity:1;transform:none}
.wtx .l{font-size:9.5px;font-weight:700;letter-spacing:.12em;color:var(--gold)}
.wtx .a{font-size:40px;font-weight:900;letter-spacing:-.03em;font-variant-numeric:tabular-nums;margin-top:2px}
.wtx .w{font-size:11px;color:#d7e3ff}
.wtx .f{font-size:9px;color:#a9bff0;margin-top:8px}
.tap{position:absolute;width:30px;height:30px;margin:-15px 0 0 -15px;border-radius:50%;background:rgba(255,255,255,.55);border:2px solid #fff;z-index:9;opacity:0;pointer-events:none}
.tap.go{animation:tap .55s var(--ease)}
@keyframes tap{0%{opacity:0;transform:scale(1.6)}35%{opacity:1;transform:scale(1)}100%{opacity:0;transform:scale(.8)}}
.ph .fx{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;z-index:8}
.ph .hb{position:absolute;bottom:7px;left:50%;transform:translateX(-50%);width:104px;height:4px;border-radius:3px;background:#fff;z-index:8}
.ph .sc.out{opacity:.0;transition:opacity .4s}
.ph .sc{transition:opacity .4s}
.paid-l{position:absolute;inset:0;z-index:6;background:linear-gradient(180deg,#d8f1fb 0%,#E3F6FD 55%,#fff 100%);color:#141a26;display:flex;flex-direction:column;align-items:center;text-align:center;padding:58px 22px 0;opacity:0;transition:opacity .45s;pointer-events:none}
.paid .paid-l{opacity:1}
.paid-l .wm{font:900 21px Inter,sans-serif;letter-spacing:-.03em;color:#002E6E}.paid-l .wm i{font-style:normal;color:#00BAF2}
.paid-l .pt{margin-top:58px;width:66px;height:66px;border-radius:50%;background:#21C17A;display:grid;place-items:center;box-shadow:0 12px 26px -10px rgba(33,193,122,.7)}
.paid .pt{animation:pop .55s var(--ease) .1s both}
@keyframes pop{from{transform:scale(.4);opacity:0}to{transform:none;opacity:1}}
.paid-l .pa{font-size:36px;font-weight:800;letter-spacing:-.02em;margin-top:16px}
.paid-l .pn{font-size:12.5px;font-weight:600;margin-top:2px}
.paid-l .pm{font-size:10px;color:#475467;margin-top:6px}
.paid-l .gw{margin-top:34px;display:flex;align-items:center;gap:8px;background:#fff6cf;border:1px solid #f3e3a1;color:#6b5200;font-size:12px;font-weight:700;border-radius:999px;padding:9px 14px}
.paid .gw{animation:up .5s var(--ease) .75s both}
@keyframes up{from{transform:translateY(10px);opacity:0}to{transform:none;opacity:1}}
.paid .st{color:#000}.paid .hb{background:#111}

/* ---------- flows: the chrome around the phones ----------
   Each step is a grey panel: screen, annotation beside it, caption under it. */
.flow-wrap{margin:var(--s3) calc(-1 * var(--pad)) 0 0}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4).rg-flow{background:transparent;padding:0 0 var(--s3);overflow:visible}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-head{justify-content:flex-end;padding:0 96px 0 0;margin:0;max-width:1272px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-track{gap:var(--s2);align-items:stretch;padding:var(--s3) 64px var(--s3) 2px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-step{zoom:.85;background:var(--panel);border-radius:var(--r3);padding:56px 64px 32px;justify-content:space-between;gap:36px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-step:has(.note){padding-right:244px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-cap{align-self:stretch;text-align:left;max-width:320px;font:400 var(--t2)/1.5 var(--sans);color:var(--pg-muted)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-cap b{display:block;font-size:var(--t3);font-weight:600;color:var(--pg-ink);margin-bottom:2px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-rail{padding:0 64px 0 0;max-width:1240px}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) :is(.rg-btn,.rg-arrow){background:var(--pg-bg);border-color:var(--pg-line);color:var(--pg-ink);font-family:var(--sans)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-btn{border-radius:var(--r1)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-stops::before{background:var(--pg-line)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) :is(.rg-fill,.rg-stop.done i,.rg-stop.cur i){background:var(--pg-ink);border-color:var(--pg-ink)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-stop i{background:var(--pg-bg);border-color:var(--pg-faint)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-stop span{font:400 var(--t1) var(--sans);color:var(--pg-faint)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-stop.cur span{color:var(--pg-ink);font-weight:500}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .anchor{position:relative}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-step>:is(.anchor,.card){margin-block:auto}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .anchor>.card{display:block}

/* annotation: dashed box on the decision, dotted leader to a label right of the phone.
   --r (set by page.js) is the box's distance from the phone's right edge, so every label lines up. */
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note{position:absolute;z-index:75;border:1.5px dashed var(--ann);border-radius:10px;background:none;pointer-events:none;opacity:0;transition:opacity .3s}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4).notes .note{opacity:1}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4).notes .phone{overflow:visible}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note b{position:absolute;left:calc(100% + var(--r,0px) + 44px);top:50%;transform:translateY(-50%);width:156px;
  font:400 var(--t2)/1.4 var(--sans);color:var(--ann-dim);background:none;border:0;border-radius:0;padding:0;box-shadow:none}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note b em{display:block;font-style:normal;font-weight:600;color:var(--ann-ink)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note b::before{content:"";position:absolute;right:calc(100% + 8px);top:50%;width:calc(var(--r,0px) + 30px);border-top:1.5px dotted var(--ann)}
:is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note b::after{content:"";position:absolute;right:calc(100% + 4px);top:50%;margin-top:-4px;border:4px solid transparent;border-left:6px solid var(--ann);border-right:0}
.rg-ann i{position:relative;width:26px;height:16px;border-radius:999px;background:var(--pg-faint);transition:background .2s}
.rg-ann i::after{content:"";position:absolute;top:2px;left:2px;width:12px;height:12px;border-radius:50%;background:#fff;transition:transform .2s var(--ease)}
.rg-ann[aria-checked="true"] i{background:var(--ann)}
.rg-ann[aria-checked="true"] i::after{transform:translateX(10px)}

/* ---------- previous / next case study ---------- */
.cs-nav{display:grid;grid-template-columns:1fr 1fr;gap:var(--s2);padding:var(--s5) var(--pad) var(--s4);border-top:1px solid var(--line)}
.cs-nav a{display:flex;flex-direction:column;gap:6px;padding:var(--s3);border:1px solid var(--line);border-radius:var(--r3);text-decoration:none;color:var(--ink);transition:border-color .2s,background .2s}
.cs-nav a:hover{border-color:var(--faint);background:var(--panel)}
.cs-nav a.next{text-align:right;align-items:flex-end}
.cs-nav small{font-size:var(--t1);letter-spacing:.08em;text-transform:uppercase;color:var(--faint)}
.cs-nav b{font:400 var(--t5)/1.15 var(--serif)}
.cs-nav span{font-size:var(--t2);color:var(--muted)}
@media (max-width:640px){.cs-nav{grid-template-columns:1fr;padding:var(--s4) var(--s2)}.cs-nav a.next{text-align:left;align-items:flex-start}}
/* ---------- responsive ---------- */
@media (max-width:1180px){.hero{grid-template-columns:1fr}}
@media (max-width:980px){
  :root{--side-w:0px}
  .side{width:260px;transform:translateX(-100%)}
  body.side-on .side{transform:none;box-shadow:0 0 60px rgba(0,0,0,.2)}
  .reopen{opacity:1;pointer-events:auto}
  body.side-on .reopen{opacity:0}
  .stages,.jt,.cpt,.feature,.qa,.acc{grid-template-columns:1fr}
  .feature-t{padding:var(--s4) var(--s4) 0}
  .feature-t::before{top:calc(var(--s4) + 4px)}
  .frag{margin:0 var(--s4) 0 var(--s4)}
  .prog li+li::before{content:"↓";left:50%;margin:0 0 0 -8px;top:calc(-1 * var(--s4) / 2 - 12px)}
}
@media (max-width:640px){
  :root{--t4:19px;--t5:24px}
  .frag{margin:0 var(--s2)}
  .feature-t{padding:var(--s4) var(--s3) 0}
  .frag-row{flex-wrap:wrap}
  .frag-row em{margin-left:52px}
  .sec{padding:88px var(--s2) var(--s4)}
  .flow-wrap{margin-right:calc(-1 * var(--s2))}
  .cols,.clusters,.split,.qa{grid-template-columns:1fr}
  .pics figure,.pics.wide figure{flex-basis:78%}
  .pics.decks .feature{flex-basis:88%}
  .pics{margin-right:calc(-1 * var(--s2));padding-right:var(--s2)}
  .loop{flex-direction:column;gap:var(--s2)}
  .loop li+li{margin-left:0}
  .loop li+li::before{position:static;margin:0 0 4px;content:"↓"}
  .loop li:last-child::after{display:none}
  .dc{padding-left:0}
  .dc td:first-child{white-space:normal}
  .dc .tbl{overflow-x:auto}
  .tbl{font-size:var(--t1)}
  :is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-head{padding-right:var(--s2)}
  :is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-step,
  :is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .rg-step:has(.note){padding:36px 24px 24px}
  /* no room beside the phone: keep the dashed boxes, drop the side labels */
  :is(#rgFlow1,#rgFlow2,#rgFlow3,#rgFlow4) .note b{display:none}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}html{scroll-behavior:auto}}