/* Pulse Pod promo. Dark, quiet, product-first (exolabs.net / affectui.com feel). */
:root {
  --bg: #060607; --bg2: #111113; --line: rgba(255,255,255,.08); --line2: rgba(255,255,255,.14);
  --tx: #f4f3ee; --mut: #b4b4bb; --mut2: #85858d;
  --acc: #3dff8a; --acc2: #b8ffd6; --gold: #e9c27a;
  --r: 18px; --maxw: 1180px;
  --sans: "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --disp: "Inter Tight", var(--sans); --mono: "JetBrains Mono", ui-monospace, monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--tx); font: 18px/1.6 var(--sans); -webkit-font-smoothing: antialiased; overflow-x: hidden; }
a { color: inherit; text-decoration: none; }
h1, h2 { font-family: var(--disp); font-weight: 600; letter-spacing: -0.035em; line-height: 1.02; margin: 0; }
h1 { font-size: clamp(42px, 5.6vw, 84px); }
h2 { font-size: clamp(32px, 3.8vw, 56px); }
p { margin: 0; }
.center { text-align: center; }
.eyebrow { font: 500 12px/1 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--acc); margin-bottom: 18px; }
.fine { color: var(--mut2); font-size: 15px; }
.grad { background: linear-gradient(92deg, #fff 0%, #cfeedd 45%, var(--acc) 100%); -webkit-background-clip: text; background-clip: text; color: transparent; }

/* nav */
.nav { position: fixed; top: 0; left: 0; right: 0; z-index: 20; display: flex; align-items: center; gap: 28px; padding: 18px max(24px, calc((100vw - var(--maxw)) / 2));
  background: linear-gradient(180deg, rgba(10,10,11,.86), rgba(10,10,11,0)); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border-bottom: 1px solid transparent; transition: border-color .3s, background .3s; }
.nav.scrolled { background: rgba(10,10,11,.72); border-bottom-color: var(--line); }
.brand { display: flex; align-items: center; gap: 10px; font: 600 16px var(--disp); letter-spacing: -.01em; }
.mark { display: inline-block; width: 32px; height: 32px; flex-shrink: 0; vertical-align: middle; }
.nav nav { display: flex; gap: 26px; margin-left: auto; font-size: 15.5px; color: var(--mut); }
.nav nav a:hover { color: var(--tx); }

/* buttons */
.btn { display: inline-flex; align-items: center; gap: 8px; height: 48px; padding: 0 22px; border-radius: 999px; font: 500 15px var(--sans); border: 1px solid var(--line2); cursor: pointer; transition: transform .2s, background .2s, border-color .2s; white-space: nowrap; }
.btn:hover { transform: translateY(-1px); }
.btn-light { background: #f4f3ee; color: #0a0a0b; border-color: #f4f3ee; }
.btn-light:hover { background: #fff; }
.btn-ghost { background: rgba(255,255,255,.04); color: var(--tx); }
.btn-ghost:hover { background: rgba(255,255,255,.08); border-color: rgba(255,255,255,.24); }
.btn-sm { height: 36px; padding: 0 16px; font-size: 13.5px; }
.arr { transition: transform .2s; } .btn:hover .arr { transform: translateX(3px); }

main { position: relative; z-index: 2; }
section { position: relative; }

/* hero */
.hero { position: relative; min-height: 100svh; display: flex; align-items: center; padding: 120px max(24px, calc((100vw - var(--maxw)) / 2)) 80px; overflow: hidden; }
.hero-img { position: absolute; inset: 0; z-index: 0; pointer-events: none; }
.hero-img img { position: absolute; right: -6vw; top: 50%; width: min(72vw, 1300px); translate: 0 -50%; will-change: transform; mask-image: radial-gradient(closest-side, #000 72%, transparent); -webkit-mask-image: radial-gradient(closest-side, #000 72%, transparent); }
.hero-img::after { content: ""; position: absolute; inset: 0; background: linear-gradient(90deg, var(--bg) 0%, rgba(6,6,7,.85) 30%, rgba(6,6,7,0) 58%), linear-gradient(0deg, var(--bg), rgba(6,6,7,0) 22%); }
.hero-copy { position: relative; z-index: 1; }
.hero-copy { max-width: 600px; }
.pill { display: inline-flex; align-items: center; gap: 10px; padding: 7px 14px 7px 12px; border-radius: 999px; border: 1px solid var(--line2); background: rgba(255,255,255,.03); font-size: 13px; color: #cfcfd4; margin-bottom: 28px; backdrop-filter: blur(6px); }
.dot { width: 7px; height: 7px; border-radius: 50%; background: var(--acc); }
.dot.live { animation: live 1.4s ease-in-out infinite; box-shadow: 0 0 0 0 rgba(61,255,138,.6); }
@keyframes live { 0% { box-shadow: 0 0 0 0 rgba(61,255,138,.55); } 70% { box-shadow: 0 0 0 8px rgba(61,255,138,0); } 100% { box-shadow: 0 0 0 0 rgba(61,255,138,0); } }
.lede { margin-top: 26px; font-size: clamp(19px, 1.5vw, 22px); color: #d0d0d6; max-width: 520px; }
.cta-row { margin-top: 34px; display: flex; gap: 12px; flex-wrap: wrap; }
.scroll-hint-unused { position: absolute; left: 50%; bottom: 28px; transform: translateX(-50%); display: flex; flex-direction: column; align-items: center; gap: 8px; font: 500 11px var(--mono); letter-spacing: .2em; text-transform: uppercase; color: var(--mut2); }
.scroll-hint span { width: 1px; height: 36px; background: linear-gradient(var(--mut2), transparent); animation: drip 2s ease-in-out infinite; }
@keyframes drip { 0% { transform: scaleY(0); transform-origin: top; } 50% { transform: scaleY(1); transform-origin: top; } 51% { transform-origin: bottom; } 100% { transform: scaleY(0); transform-origin: bottom; } }

/* stats band */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); max-width: var(--maxw); margin: 0 auto; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: rgba(10,10,11,.6); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); }
.stat { padding: 34px 28px; border-left: 1px solid var(--line); }
.stat:first-child { border-left: 0; }
.stat b { display: block; font: 600 clamp(34px, 3.6vw, 52px)/1 var(--disp); letter-spacing: -.03em; }
.stat b small { font-size: .45em; font-weight: 500; color: var(--mut); margin-left: 4px; letter-spacing: 0; }
.stat span { display: block; margin-top: 10px; color: var(--mut); font-size: 16px; }

.ecg { margin-top: 28px; display: flex; align-items: center; gap: 18px; padding: 14px 18px; border: 1px solid var(--line); border-radius: 14px; background: rgba(10,10,11,.55); backdrop-filter: blur(10px); }
.ecg svg { flex: 1; height: 40px; }
.ecg path { fill: none; stroke: var(--acc); stroke-width: 2; filter: drop-shadow(0 0 6px rgba(61,255,138,.6)); }
.bpm { font: 500 13px var(--mono); color: var(--mut); white-space: nowrap; }
.bpm b { font: 600 26px var(--disp); color: var(--tx); }

/* why: one wrist, not two */
.block { position: relative; padding: 150px max(24px, calc((100vw - var(--maxw)) / 2)); }
.sub { max-width: 640px; margin: 22px auto 0; color: var(--mut); font-size: 20px; }
.vs { margin: 64px auto 0; max-width: 920px; display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.vs-card { border: 1px solid var(--line2); border-radius: var(--r); padding: 30px 30px 34px; background: rgba(255,255,255,.02); }
.vs-card.after { border-color: rgba(61,255,138,.35); background: radial-gradient(500px 220px at 30% 0%, rgba(61,255,138,.08), transparent 70%), rgba(255,255,255,.02); }
.vs-card .tag { font: 500 12.5px var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--mut2); }
.vs-card.after .tag { color: var(--acc); }
.vs-card ul { list-style: none; margin: 18px 0 0; padding: 0; display: grid; gap: 14px; }
.vs-card li { display: flex; gap: 14px; align-items: flex-start; font-size: 18.5px; color: #dcdce0; }
.vs-card li i { flex: none; width: 22px; height: 22px; margin-top: 3px; border-radius: 50%; position: relative; }
.vs-card li i.x { border: 1px solid var(--line2); }
.vs-card li i.x::before, .vs-card li i.x::after { content: ""; position: absolute; left: 6px; top: 10px; width: 9px; height: 1.5px; background: var(--mut2); transform: rotate(45deg); }
.vs-card li i.x::after { transform: rotate(-45deg); }
.vs-card li i.ok { background: rgba(61,255,138,.15); }
.vs-card li i.ok::before { content: ""; position: absolute; left: 7px; top: 5px; width: 5px; height: 9px; border: solid var(--acc); border-width: 0 2px 2px 0; transform: rotate(45deg); }

/* faq */
.qa { max-width: 760px; margin: 56px auto 0; border-top: 1px solid var(--line); }
.qa details { border-bottom: 1px solid var(--line); padding: 4px 0; }
.qa summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 20px; padding: 22px 4px; font: 600 21px var(--disp); letter-spacing: -.01em; }
.qa summary::-webkit-details-marker { display: none; }
.qa summary::after { content: "+"; font: 400 26px var(--sans); color: var(--mut); transition: transform .25s; }
.qa details[open] summary::after { transform: rotate(45deg); color: var(--acc); }
.qa details p { padding: 0 4px 24px; color: var(--mut); font-size: 18px; max-width: 640px; }

/* specs */
.grid { margin-top: 64px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; }
.card { background: var(--bg); padding: 30px 26px 32px; transition: background .25s; }
.card:hover { background: #0f1011; }
.card .k { font: 500 12.5px var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--mut2); }
.card b { display: block; margin-top: 18px; font: 600 24px/1.15 var(--disp); letter-spacing: -.02em; }
.card p { margin-top: 10px; color: var(--mut); font-size: 16px; line-height: 1.5; }

/* progress */
.timeline { list-style: none; margin: 64px auto 0; padding: 0; max-width: 760px; position: relative; }
.timeline::before { content: ""; position: absolute; left: 7px; top: 8px; bottom: 8px; width: 1px; background: var(--line2); }
.timeline li { position: relative; padding: 0 0 38px 44px; }
.timeline li::before { content: ""; position: absolute; left: 0; top: 6px; width: 15px; height: 15px; border-radius: 50%; border: 1px solid var(--line2); background: var(--bg); }
.timeline li.done::before { background: var(--acc); border-color: var(--acc); box-shadow: 0 0 14px rgba(61,255,138,.45); }
.timeline li.now::before { border-color: var(--acc); animation: live 1.6s infinite; }
.timeline .when { font: 500 11.5px var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--mut2); }
.timeline li.done .when, .timeline li.now .when { color: var(--acc); }
.timeline b { display: block; margin-top: 6px; font: 600 21px var(--disp); letter-spacing: -.015em; }
.timeline p { margin-top: 6px; color: var(--mut); }

/* cta */
.cta { text-align: center; border-top: 1px solid var(--line); background: radial-gradient(700px 360px at 50% 0%, rgba(61,255,138,.10), transparent 70%), var(--bg); }
.cta > p { margin: 18px auto 0; color: var(--mut); max-width: 460px; font-size: 17px; }
.join { margin: 36px auto 0; display: flex; gap: 10px; max-width: 460px; padding: 6px; border: 1px solid var(--line2); border-radius: 999px; background: rgba(255,255,255,.03); }
.join input { flex: 1; min-width: 0; background: transparent; border: 0; outline: 0; color: var(--tx); font: 15px var(--sans); padding: 0 16px; }
.join .btn { height: 44px; }
#joinMsg { margin-top: 16px; min-height: 1.4em; }

footer { position: relative; z-index: 2; background: var(--bg); display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; padding: 30px max(24px, calc((100vw - var(--maxw)) / 2)) 40px; border-top: 1px solid var(--line); color: var(--mut); font-size: 14px; }
footer a { color: var(--tx); }
footer .mark { margin-right: 8px; }


/* entrance */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .9s cubic-bezier(.2,.7,.2,1), transform .9s cubic-bezier(.2,.7,.2,1); }
.reveal.in { opacity: 1; transform: none; }

@media (max-width: 900px) {
  .nav nav { display: none; }
  .nav .btn { margin-left: auto; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(3) { border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--line); }
  .grid { grid-template-columns: repeat(2, 1fr); }
  .vs { grid-template-columns: 1fr; }
  .block { padding: 100px 22px; }
  .hero { align-items: flex-end; padding-bottom: 14vh; }
}
@media (max-width: 520px) { .grid { grid-template-columns: 1fr; } .join { flex-direction: column; border-radius: 18px; } .join input { height: 46px; } }
@media (prefers-reduced-motion: reduce) { * { animation: none !important; transition: none !important; } html { scroll-behavior: auto; } }

/* feature rows: big render + copy */
.feature { display: grid; grid-template-columns: 1.25fr 1fr; align-items: center; gap: 56px; max-width: calc(var(--maxw) + 120px); margin: 0 auto; padding: 80px max(24px, calc((100vw - var(--maxw) - 120px) / 2)); }
.feature.flip { grid-template-columns: 1fr 1.25fr; }
.feature.flip .shot { order: 2; }
.feature .copy { max-width: 470px; }
.feature .copy p:not(.eyebrow):not(.fine) { margin-top: 22px; color: #cfcfd5; font-size: 20px; line-height: 1.55; }
.feature .copy .fine { margin-top: 16px; }
.shot { position: relative; margin: 0; border-radius: 28px; overflow: hidden; background: radial-gradient(120% 90% at 50% 40%, #121214, #060607 70%); aspect-ratio: 16 / 10; }
.shot img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform 1.6s cubic-bezier(.2,.7,.2,1); }
.shot.in img { transform: scale(1.0); }
.shot.reveal img { transform: scale(1.06); }
.shot figcaption { position: absolute; left: 0; right: 0; bottom: 18%; display: flex; justify-content: center; }
.dim { font: 500 15px var(--mono); color: #e8e8e8; padding: 6px 14px; border-top: 1px solid rgba(255,255,255,.4); letter-spacing: .08em; }

.scrub { position: relative; height: 320vh; }
.scrub-sticky { position: sticky; top: 0; height: 100vh; display: grid; grid-template-columns: 1.3fr 1fr; align-items: center; gap: 40px; padding: 0 max(24px, calc((100vw - var(--maxw) - 120px) / 2)); max-width: calc(var(--maxw) + 240px); margin: 0 auto; }
#explode { width: 100%; height: auto; max-height: 86vh; object-fit: contain; }
.scrub-copy p:not(.eyebrow) { margin-top: 22px; color: #cfcfd5; font-size: 20px; }
.layers { list-style: none; counter-reset: l; margin: 30px 0 0; padding: 0; display: grid; gap: 4px; }
.layers li { counter-increment: l; display: flex; gap: 14px; align-items: center; padding: 10px 0; font-size: 18px; color: var(--mut2); border-bottom: 1px solid var(--line); transition: color .4s; }
.layers li::before { content: counter(l, decimal-leading-zero); font: 500 13px var(--mono); color: var(--mut2); transition: color .4s; }
.layers li.on { color: var(--tx); }
.layers li.on::before { color: var(--acc); }

.cta { text-align: center; overflow: hidden; }
.cta-img { margin: 0 auto -40px; max-width: 760px; opacity: .9; mask-image: radial-gradient(closest-side, #000 60%, transparent); -webkit-mask-image: radial-gradient(closest-side, #000 60%, transparent); }
.cta-img img { width: 100%; display: block; }
.cta h2, .cta > p, .cta form { position: relative; }

@media (max-width: 900px) {
  .hero { align-items: flex-end; padding-bottom: 60px; }
  .hero-img img { width: 140vw; right: -40vw; top: 34%; }
  .hero-img::after { background: linear-gradient(0deg, var(--bg) 30%, rgba(6,6,7,.6) 55%, rgba(6,6,7,0) 75%); }
  .feature, .feature.flip { grid-template-columns: 1fr; gap: 28px; padding: 50px 22px; }
  .feature.flip .shot { order: 0; }
  .scrub { height: 260vh; }
  .scrub-sticky { grid-template-columns: 1fr; align-content: center; gap: 10px; padding: 70px 22px 0; }
  .layers li { padding: 6px 0; font-size: 16px; }
  .scrub-copy p:not(.eyebrow) { font-size: 17px; margin-top: 12px; }
  .scrub-copy h2 { font-size: 30px; }
}

/* vertical thickness callout, right of the pod in profile.jpg (pod spans y 44.9%..55.2%, x ..83.2%) */
.vdim { position: absolute; left: 85.5%; top: 44.9%; height: 10.3%; display: flex; align-items: center; gap: 14px; pointer-events: none; }
.vdim i { position: relative; width: 1px; height: 100%; background: rgba(255,255,255,.55); }
.vdim i::before, .vdim i::after { content: ""; position: absolute; left: -6px; width: 13px; height: 1px; background: rgba(255,255,255,.55); }
.vdim i::before { top: 0; } .vdim i::after { bottom: 0; }
.vdim b { font: 500 15px var(--mono); color: #e8e8e8; letter-spacing: .06em; white-space: nowrap; }

/* app section: phone mockup */
.feature.flip .phone-wrap { order: 2; }
.phone-wrap { margin: 0; display: grid; place-items: center; padding: 30px 0; position: relative; }
.phone-wrap::before { content: ""; position: absolute; width: 70%; aspect-ratio: 1; border-radius: 50%; background: radial-gradient(closest-side, rgba(61,255,138,.13), transparent); filter: blur(20px); }
.phone { position: relative; width: min(330px, 78vw); aspect-ratio: 9 / 19.5; border-radius: 52px; padding: 11px;
  background: linear-gradient(145deg, #3a3a3e, #121214 40%, #26262a 70%, #0c0c0d);
  box-shadow: 0 0 0 1px rgba(255,255,255,.08) inset, 0 40px 80px -20px rgba(0,0,0,.9), 0 0 0 2px #050505;
  transform: perspective(1400px) rotateY(-14deg) rotateX(4deg); transition: transform 1.2s cubic-bezier(.2,.7,.2,1); }
.app.in .phone { transform: perspective(1400px) rotateY(-8deg) rotateX(2deg); }
.screen { position: relative; height: 100%; border-radius: 42px; overflow: hidden; background: radial-gradient(120% 60% at 50% 0%, #10261a, #070708 60%); padding: 54px 20px 0; display: flex; flex-direction: column; font-family: var(--sans); }
.island { position: absolute; top: 12px; left: 50%; transform: translateX(-50%); width: 96px; height: 28px; border-radius: 20px; background: #000; }
.status { position: absolute; top: 16px; left: 30px; right: 30px; display: flex; justify-content: space-between; font: 600 13px var(--sans); color: #fff; }
.status .sig { width: 22px; height: 11px; border-radius: 3px; border: 1px solid #fff; position: relative; }
.status .sig::after { content: ""; position: absolute; inset: 1.5px; right: 5px; background: #fff; border-radius: 1px; }
.app-day { font-size: 13px; color: var(--mut2); margin: 4px 0 0; }
.ring-wrap { position: relative; width: 62%; margin: 14px auto 0; aspect-ratio: 1; }
.ring { width: 100%; height: 100%; transform: rotate(-90deg); }
.ring circle { fill: none; stroke-width: 9; stroke-linecap: round; }
.ring .track { stroke: rgba(255,255,255,.07); }
.ring .fill { stroke: var(--acc); stroke-dasharray: 0 100; transition: stroke-dasharray 1.8s cubic-bezier(.2,.7,.2,1) .3s; filter: drop-shadow(0 0 6px rgba(61,255,138,.5)); }
.app.in .ring .fill { stroke-dasharray: 86 100; }
.ring-num { position: absolute; inset: 0; display: grid; place-content: center; text-align: center; }
.ring-num b { font: 600 46px/1 var(--disp); color: #fff; letter-spacing: -.03em; }
.ring-num span { font: 500 10px var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--acc); margin-top: 6px; }
.ring-note { text-align: center; font-size: 13px; color: #cfcfd5; margin: 10px 0 14px; }
.tiles { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.tile { background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.06); border-radius: 14px; padding: 10px 12px; }
.tile span { display: block; font-size: 10.5px; color: var(--mut2); }
.tile b { font: 600 19px/1.2 var(--disp); color: #fff; }
.tile small { font-size: 11px; color: var(--mut2); font-weight: 500; }
.alert { margin-top: 8px; display: flex; gap: 10px; align-items: flex-start; background: rgba(61,255,138,.07); border: 1px solid rgba(61,255,138,.18); border-radius: 14px; padding: 10px 12px; }
.alert i { flex: none; width: 8px; height: 8px; margin-top: 4px; border-radius: 50%; background: var(--acc); box-shadow: 0 0 8px var(--acc); }
.alert b { display: block; font-size: 12px; color: #fff; }
.alert span { font-size: 11px; line-height: 1.35; color: #b4b4bb; }
.tabbar { margin-top: auto; display: flex; justify-content: space-around; padding: 14px 10px 22px; border-top: 1px solid rgba(255,255,255,.06); }
.tabbar i { width: 20px; height: 20px; border-radius: 6px; background: rgba(255,255,255,.14); }
.tabbar i.on { background: var(--acc); }
.import { margin-top: 30px; padding: 22px 24px; border: 1px solid var(--line2); border-radius: var(--r); background: var(--bg2); }
.import .k { font: 500 12px var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--gold); }
.feature .copy .import p { margin-top: 10px; font-size: 17px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.chips span { font-size: 14px; padding: 6px 12px; border-radius: 999px; border: 1px solid var(--line2); color: #e8e8e8; }
@media (max-width: 900px) {
  .feature.flip .phone-wrap { order: 0; }
  .vdim { left: auto; right: 3%; gap: 8px; } .vdim b { font-size: 12px; }
}
.ring { overflow: visible; }
.ring .fill { filter: none; }
.ring-wrap::before { content: ""; position: absolute; inset: 12%; border-radius: 50%; box-shadow: 0 0 40px rgba(61,255,138,.18); }
.alert span { display: block; margin-top: 2px; }
.app .copy h2 { font-size: clamp(36px, 4.4vw, 60px); }
.week { margin-top: 10px; padding: 10px 12px; border-radius: 14px; background: rgba(255,255,255,.04); }
.week span { font-size: 10.5px; color: var(--mut2); }
.bars { height: 54px; margin-top: 8px; display: flex; align-items: flex-end; gap: 6px; }
.bars i { flex: 1; height: var(--h); border-radius: 4px; background: rgba(255,255,255,.16); }
.bars i.on { background: var(--acc); }
/* explode frames are square; keep the stack centred and contained */
#explode { justify-self: center; width: auto; max-width: 100%; height: min(86vh, 760px); aspect-ratio: 1; }
@media (max-width: 900px) { #explode { height: min(52vh, 92vw); } }

/* custom scrollbar: thin dark track, glowing green thumb */
html { scrollbar-width: thin; scrollbar-color: #2f6b48 var(--bg); }
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: linear-gradient(180deg, #1e3a2a, #2f6b48); border-radius: 10px; border: 3px solid var(--bg); }
::-webkit-scrollbar-thumb:hover { background: linear-gradient(180deg, #2f6b48, var(--acc)); }
/* reading progress: hairline green bar along the top edge */
.progress-bar { position: fixed; top: 0; left: 0; height: 2px; width: 100%; z-index: 30; transform-origin: 0 50%; transform: scaleX(0);
  background: linear-gradient(90deg, rgba(61,255,138,.2), var(--acc)); box-shadow: 0 0 12px rgba(61,255,138,.6); pointer-events: none; }