/* ===================================================================
   Intelligent RAG · scrollytelling demo (v2)
   Dark cinematic narrative with alternating light panels.
   Chapters: 00 basics(light) → 01 problem(dark) → 02 fix(light) →
   03 proof(dark) → 04 live(stage) → 05 savings(light) → 06 hardware(dark)
   =================================================================== */

:root {
  --bg: #050D16;
  --bg-2: #081625;
  --panel: rgba(255,255,255,0.045);
  --panel-2: rgba(255,255,255,0.07);
  --line: rgba(255,255,255,0.10);
  --line-soft: rgba(255,255,255,0.06);
  --text: #E8F1F8;
  --muted: #9DB1C4;
  --muted-2: #7FA8C4;
  --blue: #009BD7;
  --blue-bright: #35C2F2;
  --blue-ice: #9DEBFF;
  --ok: #3DD68C;
  --ok-deep: #1FB67A;
  --bad: #FF6B7A;
  --bad-deep: #E64B5C;
  --gold: #FFD66B;
  --gold-soft: #FFE49A;
  --t1: #1FB67A; --t2: #11A8C4; --t3: #F2A93B;
  /* light-panel palette */
  --ink: #102539;
  --ink-muted: #4E6276;
  --paper: #F3F8FC;
  --paper-line: #DCE6EF;
  --radius: 10px; --radius-lg: 16px;
  color-scheme: dark;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Inter", "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
  background: var(--bg); color: var(--text); line-height: 1.55;
  -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
.container { max-width: 1240px; margin: 0 auto; padding: 0 28px; }
.mono { font-family: ui-monospace, "SF Mono", Menlo, monospace; }
:focus-visible { outline: 2px solid var(--blue-bright); outline-offset: 2px; border-radius: 4px; }
.skip-link { position:absolute; left:-9999px; top:0; z-index:100; background:var(--blue); color:#fff; padding:10px 16px; border-radius:0 0 8px 0; font-weight:700; }
.skip-link:focus { left:0; }

/* gradient text helpers */
.grad-gold  { background:linear-gradient(120deg,#FFD66B,#FFB347); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.grad-red   { background:linear-gradient(120deg,#FF8A95,#E64B5C); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.grad-green { background:linear-gradient(120deg,#6EE7B7,#1FB67A); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.grad-blue  { background:linear-gradient(120deg,#9DEBFF,#35C2F2); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.grad-amber { background:linear-gradient(120deg,#E8960C,#C2410C); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.gold-inline { color:var(--gold); font-weight:700; white-space:nowrap; }
.num-red { color:#FF8A95; font-variant-numeric:tabular-nums; }

/* =================== reveal-on-scroll =================== */
[data-reveal] {
  opacity: 0; transform: translateY(26px);
  transition: opacity 0.7s cubic-bezier(0.16,1,0.3,1), transform 0.7s cubic-bezier(0.16,1,0.3,1);
  transition-delay: var(--d, 0s);
  will-change: opacity, transform;
}
[data-reveal].revealed { opacity: 1; transform: none; }

/* =================== header (light) =================== */
.site-header {
  position: sticky; top: 0; z-index: 60;
  background: rgba(248,251,253,0.90); backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--paper-line);
}
.scroll-progress {
  position:absolute; top:0; left:0; height:2.5px; width:0%;
  background:linear-gradient(90deg,var(--blue),var(--blue-bright),var(--gold));
  transition:width 0.1s linear;
}
.header-inner { display:flex; align-items:center; justify-content:space-between; gap:16px; padding:12px 0; }
.brand { display:flex; align-items:center; gap:12px; font-weight:700; font-size:15.5px; color:var(--ink); }
.brand-sub { color:var(--ink-muted); font-weight:500; font-size:13px; }
.logo-chip { background:#fff; border:1px solid var(--paper-line); border-radius:7px; padding:3px 8px; display:inline-flex; align-items:center; }
.logo-chip img { height:22px; width:auto; display:block; }
.logo-chip-vp img { height:18px; }
.logo-chip-lg { padding:8px 16px; border-radius:10px; }
.logo-chip-lg img { height:36px; }
.by-vp { color:var(--ink-muted); font-size:12.5px; display:flex; align-items:center; gap:8px; }

.chapter-nav { display:flex; gap:2px; }
.chapter-nav a {
  color:var(--ink-muted); text-decoration:none; font-size:13px; font-weight:600;
  padding:7px 11px; border-radius:999px; transition:color 0.2s, background 0.2s;
}
.chapter-nav a:hover { color:var(--ink); background:rgba(16,37,57,0.07); }
.chapter-nav a.active { color:#fff; background:var(--blue); }
@media (max-width: 1080px) { .chapter-nav { display:none; } }
@media (max-width: 640px) { .by-vp { display:none; } }

/* =================== hero =================== */
.hero { position:relative; padding:108px 0 96px; overflow:hidden; }
.hero-bg { position:absolute; inset:0; pointer-events:none; }
.hero-grid {
  position:absolute; inset:-2px;
  background-image:
    linear-gradient(rgba(0,155,215,0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,155,215,0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 80% at 50% 0%, black 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 50% 0%, black 30%, transparent 78%);
}
.orb { position:absolute; border-radius:50%; filter:blur(70px); opacity:0.5; }
.orb-a { width:560px; height:560px; left:-180px; top:-220px; background:radial-gradient(circle, rgba(0,155,215,0.45), transparent 65%); animation:orbDrift 17s ease-in-out infinite alternate; }
.orb-b { width:480px; height:480px; right:-160px; top:60px;  background:radial-gradient(circle, rgba(255,196,61,0.20), transparent 65%); animation:orbDrift 23s ease-in-out infinite alternate-reverse; }
@keyframes orbDrift { from { transform:translate(0,0) scale(1); } to { transform:translate(70px,50px) scale(1.12); } }
.float-cube {
  position:absolute; width:14px; height:14px; border-radius:3px;
  background:rgba(53,194,242,0.35); border:1px solid rgba(53,194,242,0.5);
  animation:cubeFloat 9s ease-in-out infinite;
}
.fc1 { left:12%; top:64%; animation-delay:0s; }
.fc2 { left:78%; top:30%; animation-delay:-2.5s; width:10px; height:10px; }
.fc3 { left:64%; top:74%; animation-delay:-5s; width:18px; height:18px; opacity:0.6; }
.fc4 { left:30%; top:22%; animation-delay:-7s; width:9px; height:9px; }
.fc-gold {
  left:86%; top:60%; width:16px; height:16px; animation-delay:-3.6s;
  background:rgba(255,214,107,0.5); border-color:rgba(255,214,107,0.9);
  box-shadow:0 0 14px rgba(255,214,107,0.55);
}
@keyframes cubeFloat {
  0%,100% { transform:translateY(0) rotate(0deg); }
  50%     { transform:translateY(-26px) rotate(10deg); }
}

.hero-inner { position:relative; z-index:1; text-align:center; }
.hero-eyebrow {
  display:inline-block; font-size:12.5px; font-weight:700; letter-spacing:0.14em; text-transform:uppercase;
  color:var(--blue-ice); border:1px solid rgba(53,194,242,0.35); background:rgba(0,155,215,0.10);
  padding:8px 18px; border-radius:999px; margin-bottom:28px;
}
.hero h1 {
  font-size:clamp(40px,6.4vw,84px); line-height:1.04; letter-spacing:-0.03em; font-weight:800;
  margin-bottom:24px; text-wrap:balance;
}
.hero .lede { font-size:clamp(16px,1.6vw,19.5px); color:var(--muted); max-width:760px; margin:0 auto 48px; }
.hero .lede strong { color:#fff; }
.hero .lede em { color:var(--gold-soft); font-style:normal; font-weight:600; }

.hero-stats { display:grid; grid-template-columns:repeat(3,1fr); gap:16px; max-width:920px; margin:0 auto 56px; }
@media (max-width:820px){ .hero-stats { grid-template-columns:1fr; max-width:420px; } }
.hstat {
  background:var(--panel); border:1px solid var(--line); border-radius:var(--radius-lg);
  padding:26px 20px 22px; backdrop-filter:blur(6px);
  transition:transform 0.3s ease, border-color 0.3s ease;
}
.hstat:hover { transform:translateY(-4px); border-color:rgba(53,194,242,0.45); }
.hstat-gold:hover { border-color:rgba(255,214,107,0.55); }
.hstat-num { font-size:clamp(36px,3.6vw,50px); font-weight:800; letter-spacing:-0.03em; line-height:1; color:#fff; font-variant-numeric:tabular-nums; }
.hstat-unit { font-size:0.6em; font-weight:700; color:var(--muted); margin-left:2px; }
.hstat-gold .hstat-num { background:linear-gradient(120deg,#FFD66B,#FFB347); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.hstat-gold .hstat-unit { color:rgba(255,214,107,0.7); }
.hstat-label { font-size:13.5px; color:var(--text); font-weight:600; margin-top:10px; }
.hstat-sub { font-size:12px; color:var(--muted); margin-top:4px; }
.hstat-sub strong { color:#CFE3F5; }

.scroll-cue {
  display:inline-flex; flex-direction:column; align-items:center; gap:6px;
  color:var(--muted-2); text-decoration:none; font-size:12.5px; font-weight:700;
  letter-spacing:0.1em; text-transform:uppercase;
}
.scroll-cue svg { animation:cueBob 1.8s ease-in-out infinite; }
.scroll-cue:hover { color:var(--blue-ice); }
@keyframes cueBob { 0%,100% { transform:translateY(0); opacity:0.7; } 50% { transform:translateY(6px); opacity:1; } }

/* =================== chapters (shared) =================== */
.chapter { padding:104px 0; position:relative; }
.ch-eyebrow {
  display:flex; align-items:center; gap:12px;
  font-size:12.5px; font-weight:800; letter-spacing:0.16em; text-transform:uppercase;
  color:var(--blue-ice); margin-bottom:18px;
}
.ch-num {
  display:inline-grid; place-items:center; width:34px; height:34px; border-radius:50%;
  border:1.5px solid rgba(53,194,242,0.5); color:var(--blue-bright);
  font-size:13px; font-weight:800; letter-spacing:0;
}
.chapter h2, .ch-title { font-size:clamp(28px,3.8vw,46px); font-weight:800; letter-spacing:-0.025em; line-height:1.12; margin-bottom:16px; text-wrap:balance; }
.ch-lede { font-size:17px; color:var(--muted); max-width:780px; margin-bottom:44px; }
.ch-lede strong { color:#fff; }

/* =================== light panel theme =================== */
.chapter-light {
  background:linear-gradient(180deg, #F6FAFD 0%, var(--paper) 60%, #EAF2F9 100%);
  color:var(--ink);
  border-top:1px solid rgba(9,40,70,0.06);
  border-bottom:1px solid rgba(9,40,70,0.06);
  color-scheme: light;
}
.chapter-light .ch-title, .chapter-light h2 { color:var(--ink); }
.chapter-light .ch-lede { color:var(--ink-muted); }
.chapter-light .ch-lede strong { color:var(--ink); }
.chapter-light .ch-lede em { color:#B45309; font-style:normal; font-weight:600; }
.chapter-light .ch-eyebrow { color:#0077B6; }
.chapter-light .ch-num { border-color:rgba(0,119,182,0.45); color:#0077B6; }

/* =================== ch0 · basics (light) =================== */
.basics-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:18px; margin-bottom:30px; }
@media (max-width:1060px){ .basics-grid { grid-template-columns:repeat(2,1fr); } }
@media (max-width:620px){ .basics-grid { grid-template-columns:1fr; } }
.basics-card {
  background:#fff; border:1px solid var(--paper-line); border-radius:var(--radius-lg);
  padding:26px 22px 22px; position:relative;
  box-shadow:0 10px 30px rgba(15,40,70,0.06);
  transition:transform 0.3s ease, box-shadow 0.3s ease;
}
.basics-card:hover { transform:translateY(-4px); box-shadow:0 18px 44px rgba(15,40,70,0.10); }
.basics-card h3 { font-size:16.5px; font-weight:800; letter-spacing:-0.01em; color:var(--ink); margin:14px 0 8px; }
.basics-card p { font-size:13.5px; color:#52677B; }
.basics-card p strong { color:var(--ink); }
.basics-card p em { color:#B45309; font-style:normal; font-weight:700; }
.basics-fig { height:124px; display:grid; place-items:center; background:#F7FAFD; border:1px solid #E8F0F7; border-radius:10px; overflow:hidden; }
.basics-fig svg { width:100%; height:100%; display:block; }
.b-dot { animation:bTwinkle 3s ease-in-out infinite; }
@keyframes bTwinkle { 0%,100% { opacity:0.75; } 50% { opacity:1; } }
.b-ring { animation:bRing 9s linear infinite; transform-box:fill-box; transform-origin:center; }
@keyframes bRing { to { transform:rotate(360deg); } }

.basics-note {
  display:flex; align-items:center; gap:14px;
  background:linear-gradient(135deg,#FFF8E4,#FFF3D1);
  border:1px solid #EFD9A0; border-radius:var(--radius-lg);
  padding:16px 22px; font-size:15px; line-height:1.55; color:#6B4E0E;
}
.basics-note strong { color:#4F3A07; }
.basics-note-star { font-size:26px; line-height:1; color:#E8A516; flex:0 0 auto; filter:drop-shadow(0 0 6px rgba(232,165,22,0.4)); }

/* =================== ch1 · problem =================== */
.split { display:grid; grid-template-columns:1fr 1fr; gap:56px; align-items:center; }
@media (max-width:920px){ .split { grid-template-columns:1fr; gap:32px; } }
.split-copy h2 { margin-bottom:20px; }
.split-copy p { font-size:16px; color:var(--muted); margin-bottom:16px; max-width:560px; }
.split-copy p strong { color:#fff; }

.problem-readout { display:flex; gap:36px; margin-top:28px; padding-top:24px; border-top:1px solid var(--line-soft); }
.pr-item { display:flex; flex-direction:column; gap:4px; }
.pr-num { font-size:34px; font-weight:800; letter-spacing:-0.02em; color:#FF8A95; font-variant-numeric:tabular-nums; }
.pr-num.pr-gold { color:var(--gold); }
.pr-label { font-size:12px; color:var(--muted); text-transform:uppercase; letter-spacing:0.07em; font-weight:700; }

.chunkwall-card {
  background:var(--panel); border:1px solid var(--line); border-radius:var(--radius-lg);
  padding:18px 20px 14px; box-shadow:0 24px 60px rgba(0,0,0,0.35);
}
.chunkwall-head { display:flex; justify-content:space-between; align-items:center; font-size:12px; font-weight:700; letter-spacing:0.08em; text-transform:uppercase; color:var(--muted-2); margin-bottom:12px; }
.chunkwall-tag { color:var(--gold); letter-spacing:0.04em; transition:color 0.4s; }
#chunkWall { width:100%; height:auto; display:block; }
.chunkwall-foot { font-size:12px; color:var(--muted-2); text-align:center; margin-top:10px; }

.wall-cube { transition: opacity 0.5s ease, filter 0.5s ease; }
.wall-cube.dimmed { opacity:0.13; filter:saturate(0.3); }
.wall-gold { filter:drop-shadow(0 0 10px rgba(255,214,107,0.95)); animation:goldPulse 2s ease-in-out infinite; }
.wall-gold-label { font-size:13px; font-weight:800; letter-spacing:0.08em; fill:var(--gold); text-transform:uppercase;
  paint-order:stroke; stroke:rgba(5,13,22,0.9); stroke-width:4px; stroke-linejoin:round; opacity:0; transition:opacity 0.5s; }
.wall-gold-label.show { opacity:1; }

/* =================== ch2 · idea / steps (light) =================== */
.steps { display:grid; grid-template-columns:1fr auto 1.15fr auto 1fr; gap:18px; align-items:stretch; }
@media (max-width:980px){ .steps { grid-template-columns:1fr; } .step-arrow { transform:rotate(90deg); justify-self:center; } }
.step {
  background:#fff; border:1px solid var(--paper-line); border-radius:var(--radius-lg);
  padding:28px 26px; position:relative;
  box-shadow:0 10px 30px rgba(15,40,70,0.06);
  transition:transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}
.step:hover { transform:translateY(-5px); border-color:#7CC4E8; box-shadow:0 18px 44px rgba(15,40,70,0.12); }
.step-hero { border-color:#9AD4F0; background:linear-gradient(180deg, #EAF6FD, #fff); }
.step-badge {
  position:absolute; top:-15px; left:24px; width:30px; height:30px; border-radius:50%;
  display:grid; place-items:center; font-weight:800; font-size:14px; color:#fff;
  background:#7A8FA3; box-shadow:0 4px 12px rgba(15,40,70,0.25);
}
.step-badge-blue { background:#0099D8; }
.step-badge-green { background:#15A86B; }
.step h3 { font-size:19px; font-weight:800; letter-spacing:-0.01em; margin:18px 0 8px; color:var(--ink); }
.step p { font-size:14px; color:#52677B; }
.step p strong { color:var(--ink); }
.step-arrow { align-self:center; font-size:26px; color:#8AA3B8; font-weight:300; }

.step-visual { height:96px; display:grid; place-items:center; position:relative; }
.step-chassis { width:88%; max-width:280px; position:relative; z-index:1; filter:drop-shadow(0 4px 14px rgba(0,120,180,0.35)); animation:hwPulse 3.2s ease-in-out infinite; border-radius:4px; }
.step-chassis-glow { position:absolute; inset:10% 6%; background:radial-gradient(ellipse, rgba(53,194,242,0.22), transparent 70%); }
.mini-grid { display:grid; grid-template-columns:repeat(20,1fr); gap:2px; width:100%; max-width:260px; }
.mini-grid-ten { grid-template-columns:repeat(10,1fr); max-width:150px; }
.mini-cell { aspect-ratio:1; border-radius:1.5px; background:rgba(0,153,216,0.35); animation:miniTwinkle 3s ease-in-out infinite; }
.mini-grid-ten .mini-cell { background:rgba(21,168,107,0.5); }
.mini-cell.gold { background:#E8A516; box-shadow:0 0 8px rgba(232,165,22,0.7); animation:goldPulse 2s ease-in-out infinite; }
@keyframes miniTwinkle { 0%,100% { opacity:0.55; } 50% { opacity:1; } }

/* =================== ch3 · proof (dark) =================== */
.proof-grid { display:grid; grid-template-columns:1.5fr 1fr; gap:24px; align-items:stretch; }
@media (max-width:980px){ .proof-grid { grid-template-columns:1fr; } }
.curve-card, .kx-card {
  background:var(--panel); border:1px solid var(--line); border-radius:var(--radius-lg);
  padding:22px 24px;
}
.curve-head { display:flex; justify-content:space-between; align-items:center; gap:14px; flex-wrap:wrap; margin-bottom:8px; }
.curve-title { font-size:12px; font-weight:800; letter-spacing:0.1em; text-transform:uppercase; color:var(--muted-2); }
.curve-legend { display:flex; gap:16px; font-size:12px; color:var(--muted); }
.curve-legend span { display:inline-flex; align-items:center; gap:6px; }
.sw { width:11px; height:11px; border-radius:3px; display:inline-block; }
.sw-green { background:var(--ok); } .sw-red { background:var(--bad-deep); } .sw-gold { background:#FFC53D; }
#recallChart { width:100%; height:auto; display:block; }

#recallChart text { font-family:inherit; }
.axis-label { font-size:11px; fill:var(--muted-2); }
.axis-tick  { font-size:11px; fill:var(--muted); font-variant-numeric:tabular-nums; }
.curve-path { fill:none; stroke-width:3.5; stroke-linecap:round; stroke-linejoin:round; }
.curve-dense { stroke:var(--bad-deep); }
.curve-hybrid { stroke:var(--ok); filter:drop-shadow(0 0 6px rgba(61,214,140,0.45)); }
.curve-dot { stroke-width:2.5; }
.anno-line { stroke:var(--gold); stroke-width:1.6; stroke-dasharray:5 5; opacity:0; transition:opacity 0.7s ease 0.2s; }
.anno-on .anno-line { opacity:1; }
.endpoint-label { font-size:12.5px; font-weight:800; font-variant-numeric:tabular-nums;
  paint-order:stroke; stroke:rgba(5,13,22,0.9); stroke-width:4px; stroke-linejoin:round; }
.kmarker { transition:transform 0.45s cubic-bezier(0.22,0.61,0.36,1); }
.kmarker circle { filter:drop-shadow(0 0 6px rgba(255,255,255,0.35)); }
.kmarker-line { stroke:rgba(255,255,255,0.22); stroke-width:1.2; stroke-dasharray:3 4; transition:transform 0.45s cubic-bezier(0.22,0.61,0.36,1); }

/* gold takeaway moved OUT of the chart so it can never overlap data */
.proof-caption {
  margin-top:14px; padding:13px 16px;
  background:linear-gradient(135deg, rgba(255,214,107,0.10), rgba(255,214,107,0.03));
  border:1px solid rgba(255,214,107,0.3); border-radius:10px;
  font-size:14px; line-height:1.5; color:var(--gold-soft);
  opacity:0; transform:translateY(8px);
  transition:opacity 0.6s ease, transform 0.6s ease;
}
.proof-caption.show { opacity:1; transform:none; }
.proof-caption strong { color:var(--gold); }

.kx-card { display:flex; flex-direction:column; gap:16px; }
.kx-head { font-size:12px; font-weight:800; letter-spacing:0.1em; text-transform:uppercase; color:var(--muted-2); }
.kx-kline { font-size:14px; color:var(--muted); }
.kx-k { font-size:26px; font-weight:800; color:#fff; font-variant-numeric:tabular-nums; padding:0 2px; }
.kx-rows { display:flex; flex-direction:column; gap:12px; }
.kx-row { display:grid; grid-template-columns:84px 1fr 58px; gap:12px; align-items:center; }
.kx-name { font-size:12.5px; font-weight:700; color:var(--muted); }
.kx-bar { height:14px; border-radius:7px; background:rgba(255,255,255,0.07); overflow:hidden; }
.kx-bar span { display:block; height:100%; border-radius:7px; width:0%; transition:width 0.5s cubic-bezier(0.22,0.61,0.36,1); }
.kx-row-green .kx-bar span { background:linear-gradient(90deg,var(--ok-deep),var(--ok)); box-shadow:0 0 10px rgba(61,214,140,0.4); }
.kx-row-red .kx-bar span { background:linear-gradient(90deg,#B23A48,var(--bad-deep)); }
.kx-val { font-size:15px; font-weight:800; text-align:right; font-variant-numeric:tabular-nums; }
.kx-row-green .kx-val { color:var(--ok); }
.kx-row-red .kx-val { color:#FF8A95; }
.kx-tokens { background:rgba(0,0,0,0.25); border:1px solid var(--line-soft); border-radius:10px; padding:14px 16px; display:flex; flex-direction:column; gap:2px; }
.kx-tokens-label { font-size:10.5px; font-weight:800; letter-spacing:0.1em; text-transform:uppercase; color:var(--muted-2); }
.kx-tokens-val { font-size:30px; font-weight:800; letter-spacing:-0.02em; font-variant-numeric:tabular-nums; color:#fff; }
.kx-tokens-note { font-size:12px; color:var(--muted); line-height:1.45; }
.kx-verdict {
  margin-top:auto; font-size:13.5px; line-height:1.5; color:var(--gold-soft);
  background:linear-gradient(135deg, rgba(255,214,107,0.10), rgba(255,214,107,0.03));
  border:1px solid rgba(255,214,107,0.3); border-radius:10px; padding:13px 16px;
  min-height:74px;
}
.kx-verdict strong { color:var(--gold); }

/* =================== ch4 · live stage =================== */
.chapter-stage {
  background:
    radial-gradient(circle at 16% 22%, rgba(0,155,215,0.13), transparent 44%),
    radial-gradient(circle at 84% 75%, rgba(91,63,160,0.13), transparent 44%),
    linear-gradient(180deg,#04101B 0%, #0A1C2D 100%);
  border-top:1px solid var(--line-soft); border-bottom:1px solid var(--line-soft);
}
.loading { padding:80px 0; text-align:center; color:var(--muted); }
.errbox { background:rgba(230,75,92,0.12); border:1px solid rgba(230,75,92,0.4); color:#ffd9dd; border-radius:10px; padding:18px 22px; margin:20px 0; font-size:14px; }
.errbox code { background:rgba(0,0,0,0.3); padding:2px 6px; border-radius:4px; }

.phase-track { display:flex; gap:8px; flex-wrap:wrap; margin-bottom:16px; }
.phase {
  display:inline-flex; align-items:center; gap:8px;
  font-size:12px; font-weight:700; letter-spacing:0.06em; text-transform:uppercase;
  color:var(--muted-2); background:var(--panel); border:1px solid var(--line-soft);
  border-radius:999px; padding:7px 16px 7px 8px; transition:all 0.3s ease;
}
.phase i {
  font-style:normal; display:inline-grid; place-items:center; width:20px; height:20px;
  border-radius:50%; background:rgba(255,255,255,0.08); font-size:11px; font-weight:800;
}
.phase.active { color:#06121E; background:var(--blue-bright); border-color:var(--blue-bright); box-shadow:0 0 18px rgba(53,194,242,0.4); }
.phase.active i { background:rgba(0,0,0,0.18); color:#06121E; }
.phase.done { color:var(--blue-ice); border-color:rgba(53,194,242,0.3); }

/* the question being replayed — types in per query */
.question-card {
  background:rgba(0,155,215,0.07); border:1px solid rgba(53,194,242,0.3);
  border-radius:12px; padding:14px 18px 16px; margin-bottom:16px;
}
.qc-head { display:flex; justify-content:space-between; align-items:baseline; gap:12px; margin-bottom:6px; }
.qc-eyebrow { font-size:10.5px; font-weight:800; letter-spacing:0.12em; text-transform:uppercase; color:var(--blue-ice); }
.qc-count { font-size:11px; font-weight:700; color:var(--muted-2); font-variant-numeric:tabular-nums; font-family:ui-monospace,Menlo,monospace; }
.qc-text { font-size:17px; font-weight:600; color:#fff; line-height:1.45; min-height:25px; }
.qc-text::after { content:''; display:inline-block; width:9px; height:18px; margin-left:3px; vertical-align:-3px; background:var(--blue-bright); animation:caretBlink 0.9s steps(1) infinite; }
@keyframes caretBlink { 50% { opacity:0; } }

.stats-bar { display:grid; grid-template-columns:repeat(5,1fr); gap:1px; background:rgba(255,255,255,0.08); border:1px solid var(--line); border-radius:var(--radius-lg); overflow:hidden; margin-bottom:18px; }
@media (max-width:760px){ .stats-bar{ grid-template-columns:repeat(2,1fr); } }
.stat { background:rgba(7,20,33,0.75); padding:16px 18px; }
.stat .label { font-size:11px; letter-spacing:0.08em; text-transform:uppercase; color:var(--muted); font-weight:700; margin-bottom:8px; }
.stat .value { font-size:24px; font-weight:800; color:#fff; letter-spacing:-0.02em; font-variant-numeric:tabular-nums; transition:text-shadow 0.4s ease; }
.stat .value.accent { color:var(--ok); }
.stat.savings .value { background:linear-gradient(135deg,#1FB67A,#6EE7B7); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.stat.savings .value.flash { text-shadow:0 0 20px rgba(31,182,122,0.55); }
.stat .sub { font-size:11px; color:var(--muted); margin-top:2px; font-variant-numeric:tabular-nums; }

.stage-dual { display:flex; flex-direction:column; gap:16px; margin-bottom:14px; }
.lane {
  background:rgba(255,255,255,0.04); border:1px solid var(--line);
  border-radius:var(--radius-lg); padding:14px 16px 12px;
  display:flex; flex-direction:column; min-width:0;
}
.lane.lane-standard    { border-top:3px solid var(--bad-deep); }
.lane.lane-intelligent { border-top:3px solid var(--ok-deep); box-shadow:0 0 38px rgba(31,182,122,0.07); }
.lane-head { display:flex; justify-content:space-between; align-items:flex-start; gap:10px; margin-bottom:8px; flex-wrap:wrap; }
.lane-title { display:flex; flex-direction:column; gap:1px; }
.lane-eyebrow { font-size:11px; font-weight:800; letter-spacing:0.12em; text-transform:uppercase; color:var(--muted); }
.lane-eyebrow.accent { color:#6EE7B7; }
.lane-sub { font-size:12.5px; color:#fff; font-weight:600; }
.lane-stat { text-align:right; }
.lane-stat-num { font-size:21px; font-weight:800; color:#fff; font-variant-numeric:tabular-nums; letter-spacing:-0.01em; display:block; line-height:1; }
.lane-stat-num.accent { background:linear-gradient(135deg,#1FB67A,#6EE7B7); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent; }
.lane-stat-unit { font-size:10.5px; color:var(--muted); letter-spacing:0.06em; text-transform:uppercase; }

.lane-svg { width:100%; height:auto; display:block; flex:0 0 auto; }
.lane-svg text { fill:var(--text); font-family:inherit; }
.lane-svg .lane-label { font-size:10.5px; fill:var(--muted); letter-spacing:0.08em; text-transform:uppercase; }
.lane-svg .lane-zone-label { font-size:9.5px; fill:var(--muted-2); letter-spacing:0.1em; text-transform:uppercase; }

/* lane SVG components */
.db-box { fill:rgba(0,155,215,0.10); stroke:rgba(0,155,215,0.5); stroke-width:1.4; rx:10; ry:10; }
.db-title { font-size:11px; font-weight:800; fill:var(--blue-ice); letter-spacing:0.08em; }
.db-sub { font-size:9.5px; fill:var(--muted-2); }
.flow-line { stroke:rgba(127,168,196,0.28); stroke-width:1.5; stroke-dasharray:5 5; fill:none; animation:queryFlow 1.4s linear infinite; }
@keyframes queryFlow { to { stroke-dashoffset:-20; } }
.ghost-box { fill:rgba(230,75,92,0.04); stroke:rgba(230,75,92,0.45); stroke-width:1.6; stroke-dasharray:7 6; rx:10; ry:10; }
.ghost-title { font-size:11px; font-weight:800; fill:#FF8A95; letter-spacing:0.08em; }
.ghost-sub { font-size:9.5px; fill:#C98A93; }
.rank-text { font-size:13px; font-weight:700; paint-order:stroke; stroke:rgba(5,13,22,0.85); stroke-width:3px; stroke-linejoin:round; }
.tokens-billed-val { font-size:14px; font-weight:800; fill:#fff; font-variant-numeric:tabular-nums; }

.src-pulse { fill-opacity:0; animation:srcPulse 0.7s ease-out 1; }
@keyframes srcPulse { 0% { fill-opacity:0.7; } 100% { fill-opacity:0; } }

/* cubes */
.cube { transition:fill 0.25s ease, opacity 0.25s ease; }
.cube-rfc       { fill:#1FB67A; }
.cube-k8s       { fill:#11A8C4; }
.cube-wikipedia { fill:#F2A93B; }
.cube-other     { fill:#9DB1C4; }
.cube-gold {
  fill:var(--gold); stroke:var(--gold-soft); stroke-width:2.2;
  filter:drop-shadow(0 0 8px rgba(255,214,107,0.95));
  animation:goldPulse 2s ease-in-out infinite;
}
@keyframes goldPulse {
  0%,100% { filter:drop-shadow(0 0 6px  rgba(255,214,107,0.75)); }
  50%     { filter:drop-shadow(0 0 14px rgba(255,214,107,1.0));  }
}
.cube-faded { opacity:0.16; }
.gold-label-text {
  font-size:11px; font-weight:800; letter-spacing:0.08em; fill:var(--gold); text-transform:uppercase;
  paint-order:stroke; stroke:rgba(6,18,30,0.85); stroke-width:3px; stroke-linejoin:round; pointer-events:none;
}
.gold-label-star { fill:var(--gold-soft); }

.llm-box { rx:8; ry:8; fill:rgba(255,255,255,0.06); stroke:rgba(255,255,255,0.28); stroke-width:1; transition:fill 0.3s ease, stroke 0.3s ease; }
.llm-box.recv { fill:rgba(0,155,215,0.18); stroke:var(--blue); }

.verdict-strip {
  display:flex; justify-content:space-between; align-items:center; gap:18px; flex-wrap:wrap;
  margin-top:8px; padding:9px 14px;
  background:rgba(0,0,0,0.25); border:1px solid var(--line-soft); border-radius:8px;
  font-size:13.5px; color:var(--text);
}
.verdict-msg { font-weight:600; transition:color 0.3s; }
.verdict-msg.hit  { color:#6EE7B7; }
.verdict-msg.miss { color:#FF8A95; }
.verdict-recall { display:inline-flex; align-items:baseline; gap:8px; font-family:ui-monospace,Menlo,monospace; }
.verdict-recall-label { font-size:10.5px; color:var(--muted); letter-spacing:0.06em; text-transform:uppercase; }
.verdict-recall-val { font-size:18px; font-weight:800; color:#fff; font-variant-numeric:tabular-nums; min-width:54px; text-align:right; }
.verdict-recall-val.accent { color:#6EE7B7; }
.verdict-recall-val.tick { animation:recallTick 0.4s ease-out; }
@keyframes recallTick { 0% { transform:scale(1.07); color:var(--gold); } 100% { transform:scale(1); } }
.verdict-recall-n { font-size:11px; color:var(--muted-2); }

/* head-to-head outcome banner */
.cycle-outcome {
  display:flex; gap:14px; align-items:flex-start;
  padding:15px 18px; border-radius:12px; margin-bottom:18px;
  font-size:14.5px; line-height:1.5;
  background:var(--panel); border:1px solid var(--line); color:var(--muted);
  transition:border-color 0.35s ease, background 0.35s ease, opacity 0.35s ease;
}
.cycle-outcome.stale { opacity:0.5; }
.cycle-outcome .co-ico { font-size:20px; line-height:1.2; flex:0 0 auto; }
.cycle-outcome .co-text strong { color:#fff; }
.cycle-outcome.good { border-color:rgba(61,214,140,0.45); background:rgba(31,182,122,0.08); color:#CFF5E3; }
.cycle-outcome.gold { border-color:rgba(255,214,107,0.5); background:rgba(255,214,107,0.07); color:var(--gold-soft); }
.cycle-outcome.gold .co-text strong { color:var(--gold); }
.cycle-outcome.bad  { border-color:rgba(230,75,92,0.45); background:rgba(230,75,92,0.07); color:#FFD9DD; }
.cycle-outcome.mixed{ border-color:rgba(255,196,61,0.4); background:rgba(255,196,61,0.05); color:#F4E2B6; }

/* replay cumulative chart */
.chart-wrap { background:rgba(0,0,0,0.2); border-radius:10px; padding:10px 14px; border:1px solid var(--line-soft); margin-bottom:20px; }
.chart-svg { width:100%; height:130px; display:block; }
.chart-header { display:flex; justify-content:space-between; padding:4px 6px 8px; flex-wrap:wrap; gap:8px; }
.chart-title { font-size:11px; font-weight:700; color:var(--muted); letter-spacing:0.1em; text-transform:uppercase; }
.chart-legend { display:flex; gap:12px; font-size:11px; color:var(--muted); }
.chart-legend span { display:inline-flex; align-items:center; gap:5px; }
.chart-svg #savingsLabel { fill:var(--gold); font-weight:800; font-size:13px; font-family:ui-monospace,Menlo,monospace; paint-order:stroke; stroke:rgba(6,18,30,0.9); stroke-width:3px; stroke-linejoin:round; }

/* controls */
.controls { display:flex; gap:12px; flex-wrap:wrap; align-items:center; justify-content:space-between; margin-bottom:8px; }
.control-group { display:flex; gap:10px; align-items:center; flex-wrap:wrap; }
.ctrl-btn {
  background:rgba(255,255,255,0.08); color:#fff; border:1px solid rgba(255,255,255,0.15);
  padding:10px 18px; border-radius:8px; font-size:14px; font-weight:600; cursor:pointer;
  font-family:inherit; transition:all 0.15s;
}
.ctrl-btn:hover { background:rgba(255,255,255,0.14); }
.ctrl-btn.active { background:var(--blue); border-color:var(--blue); color:#06121e; }
.speed-group { display:inline-flex; border-radius:8px; overflow:hidden; border:1px solid rgba(255,255,255,0.15); }
.speed-group .ctrl-btn { border:none; border-radius:0; padding:10px 14px; }
.speed-group .ctrl-btn + .ctrl-btn { border-left:1px solid rgba(255,255,255,0.12); }
.next-countdown-row { display:flex; justify-content:flex-end; margin:0 0 4px; }
.next-countdown { font-size:12px; color:var(--muted); font-variant-numeric:tabular-nums; min-width:64px; font-family:ui-monospace,Menlo,monospace; }

/* pickers */
.qpicker-group { gap:12px; margin-left:auto; }
.qpicker { position:relative; min-width:180px; max-width:240px; flex:0 1 auto; }
.qpicker.qpicker-wide { min-width:280px; max-width:380px; }
.qpicker-field {
  width:100%; display:flex; align-items:center; gap:10px;
  background:rgba(255,255,255,0.06); border:1px solid rgba(255,255,255,0.14);
  color:#EAF5FF; padding:8px 12px; border-radius:10px;
  font-family:inherit; font-size:13px; font-weight:600; cursor:pointer; text-align:left;
  transition:background 0.15s, border-color 0.15s, box-shadow 0.15s;
}
.qpicker-field:hover { background:rgba(255,255,255,0.10); border-color:rgba(255,255,255,0.22); }
.qpicker.open .qpicker-field { background:rgba(0,155,215,0.14); border-color:var(--blue); box-shadow:0 0 0 3px rgba(0,155,215,0.18); }
.qpicker-eyebrow { font-size:10px; font-weight:800; letter-spacing:0.1em; text-transform:uppercase; color:#8FBEDD; flex:0 0 auto; }
.qpicker-value { display:block; color:#fff; font-size:13.5px; font-weight:600; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; max-width:100%; flex:1 1 auto; min-width:0; }
.qpicker-caret { flex:0 0 auto; color:#8FBEDD; transition:transform 0.25s cubic-bezier(0.16,1,0.3,1); }
.qpicker.open .qpicker-caret { transform:rotate(180deg); color:var(--blue); }
.qpicker-menu {
  position:absolute; top:calc(100% + 8px); right:0; left:0; z-index:30;
  background:#0c1e2e; border:1px solid rgba(255,255,255,0.16); border-radius:12px;
  box-shadow:0 16px 40px rgba(0,0,0,0.45), 0 2px 6px rgba(0,0,0,0.3);
  padding:6px; opacity:0; transform:translateY(-8px) scale(0.985);
  transform-origin:top center; pointer-events:none;
  transition:opacity 0.18s ease, transform 0.22s cubic-bezier(0.16,1,0.3,1);
  max-height:0; overflow:hidden;
}
.qpicker.open .qpicker-menu { opacity:1; transform:translateY(0) scale(1); pointer-events:auto; max-height:420px; overflow:visible; }
.qpicker-menu-q { padding:8px; }
.qpicker-search-wrap { padding:2px 2px 8px; }
.qpicker-search {
  width:100%; background:#06121e; color:#EAF5FF; border:1px solid rgba(255,255,255,0.14);
  border-radius:8px; padding:8px 12px; font-family:inherit; font-size:13px; outline:none;
  transition:border-color 0.15s, box-shadow 0.15s;
}
.qpicker-search:focus { border-color:var(--blue); box-shadow:0 0 0 3px rgba(0,155,215,0.22); }
.qpicker-list { max-height:340px; overflow-y:auto; scrollbar-width:thin; scrollbar-color:rgba(255,255,255,0.25) transparent; }
.qpicker-list::-webkit-scrollbar { width:8px; }
.qpicker-list::-webkit-scrollbar-thumb { background:rgba(255,255,255,0.18); border-radius:8px; }
.qpicker-option {
  display:flex; align-items:center; gap:10px; width:100%;
  padding:9px 12px; border-radius:8px; background:transparent;
  color:var(--text); font-family:inherit; font-size:13px; text-align:left; cursor:pointer;
  border:none; transition:background 0.12s, color 0.12s, transform 0.12s;
}
.qpicker-option:hover { background:rgba(0,155,215,0.14); }
.qpicker-option.selected { background:rgba(0,155,215,0.22); color:#fff; }
.qpicker-option:active { transform:scale(0.99); }
.qpicker-option .opt-meta { color:#8FBEDD; font-size:11px; font-weight:700; margin-left:auto; padding-left:8px; white-space:nowrap; }
.qpicker-option .opt-tier { display:inline-flex; align-items:center; gap:5px; padding:2px 8px; border-radius:999px; font-size:10.5px; font-weight:800; letter-spacing:0.04em; }
.qpicker-option .opt-tier-dot { width:7px; height:7px; border-radius:50%; }
.qpicker-empty { padding:14px 12px; color:#8FBEDD; font-size:13px; text-align:center; }

/* =================== ch5 · calculator (light) =================== */
.calc-card {
  background:#fff; border:1px solid var(--paper-line); border-radius:var(--radius-lg);
  padding:36px; display:grid; grid-template-columns:1fr 1.05fr; gap:48px; align-items:center;
  box-shadow:0 18px 50px rgba(15,40,70,0.09);
}
@media (max-width:820px){ .calc-card { grid-template-columns:1fr; gap:28px; } }
.calc-input label { display:block; font-size:12px; font-weight:700; color:#5A6B7A; text-transform:uppercase; letter-spacing:0.08em; margin-bottom:10px; }
.calc-value { font-size:30px; font-weight:700; margin-bottom:18px; font-variant-numeric:tabular-nums; color:var(--ink); }
.calc-value span { color:#7A8B9A; font-size:16px; font-weight:500; }
.slider { -webkit-appearance:none; appearance:none; width:100%; height:6px; background:rgba(255,255,255,0.12); border-radius:3px; outline:none; }
.chapter-light .slider { background:#D8E3EC; }
.slider::-webkit-slider-thumb {
  -webkit-appearance:none; width:24px; height:24px; background:var(--blue-bright);
  border-radius:50%; cursor:pointer; border:3px solid #fff; box-shadow:0 2px 12px rgba(53,194,242,0.6);
}
.chapter-light .slider::-webkit-slider-thumb { background:#0099D8; box-shadow:0 2px 10px rgba(0,120,180,0.45); }
.slider::-moz-range-thumb { width:20px; height:20px; background:var(--blue-bright); border-radius:50%; cursor:pointer; border:3px solid #fff; }
.chapter-light .slider::-moz-range-thumb { background:#0099D8; }
.slider-range { display:flex; justify-content:space-between; font-size:12px; color:#7A8B9A; margin-top:10px; }
.model-row { margin-top:24px; display:flex; flex-direction:column; gap:6px; }
.model-label { font-size:11px; font-weight:700; color:#5A6B7A; text-transform:uppercase; letter-spacing:0.08em; }
.model-select {
  width:100%; padding:11px 14px; font-size:14px; font-weight:600; font-family:inherit;
  color:var(--ink); background:#fff; border:1px solid #C9D7E3; border-radius:8px; cursor:pointer;
}
.model-select:focus { border-color:#0099D8; box-shadow:0 0 0 3px rgba(0,153,216,0.16); outline:none; }

.calc-output { border-left:1px solid #E4EBF2; padding-left:48px; }
@media (max-width:820px){ .calc-output { border-left:none; border-top:1px solid #E4EBF2; padding-left:0; padding-top:26px; } }
.savings-amount {
  font-size:clamp(48px,6.5vw,70px); font-weight:800; letter-spacing:-0.035em; line-height:1; margin-bottom:8px;
  background:linear-gradient(120deg,#E8960C,#C2410C); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent;
  font-variant-numeric:tabular-nums;
}
.savings-label { font-size:15px; color:#5A6B7A; margin-bottom:20px; }
.cost-bars { display:flex; flex-direction:column; gap:10px; margin-bottom:18px; }
.cb-row { display:grid; grid-template-columns:88px 1fr 92px; gap:12px; align-items:center; }
.cb-name { font-size:12.5px; font-weight:700; color:#5A6B7A; }
.cb-track { height:16px; border-radius:8px; background:#E7EEF4; overflow:hidden; }
.cb-fill { display:block; height:100%; border-radius:8px; width:0%; transition:width 0.5s cubic-bezier(0.22,0.61,0.36,1); }
.cb-red { background:linear-gradient(90deg,#D45563,#B23A48); }
.cb-green { background:linear-gradient(90deg,#15A86B,#3DD68C); }
.cb-val { font-size:14px; font-weight:800; text-align:right; font-variant-numeric:tabular-nums; color:var(--ink); }
.savings-vs { font-size:13px; color:#7A8B9A; }

.methodology { margin-top:24px; font-size:13.5px; color:#5A6B7A; }
.methodology summary { cursor:pointer; font-weight:700; color:#0077B6; width:fit-content; }
.methodology-body { margin-top:12px; max-width:760px; line-height:1.65; }
.methodology-body p { margin-bottom:8px; }
.methodology-body strong { color:var(--ink); }
.methodology code { background:#EFF5FA; border:1px solid #D7E3ED; padding:1px 6px; border-radius:4px; font-size:12px; color:#075985; }

/* =================== ch6 · hardware (dark hero) =================== */
.chapter-hw {
  background:
    radial-gradient(circle at 50% 0%, rgba(0,155,215,0.12), transparent 52%),
    linear-gradient(180deg, var(--bg-2) 0%, var(--bg) 100%);
  border-top:1px solid var(--line-soft);
}
.hw-flow-card {
  background:var(--panel); border:1px solid var(--line); border-radius:var(--radius-lg);
  padding:26px 24px 16px; margin-bottom:24px;
  box-shadow:0 24px 70px rgba(0,0,0,0.35);
}
.hw-flow-card svg { width:100%; height:auto; display:block; overflow:visible; }
.hwn-box { fill:rgba(255,255,255,0.06); stroke:rgba(255,255,255,0.26); stroke-width:1.2; }
.hwn-box-llm { stroke:rgba(61,214,140,0.5); fill:rgba(61,214,140,0.05); }
.hwn-title { font-size:13px; font-weight:800; fill:var(--blue-ice); letter-spacing:0.08em; }
.hwn-sub { font-size:10.5px; fill:var(--muted-2); }
.hw-band-label { font-size:13px; font-weight:800; letter-spacing:0.02em;
  paint-order:stroke; stroke:rgba(5,13,22,0.85); stroke-width:4px; stroke-linejoin:round; }
.hw-band-red { fill:#FF8A95; }
.hw-band-green { fill:#6EE7B7; }
.hw-drop-label { font-size:11.5px; font-weight:700; fill:#8A9BAB; letter-spacing:0.04em; }
.hw-r470-title { font-size:14px; font-weight:800; fill:#fff; letter-spacing:0.14em; }
.hw-dash { fill:none; stroke-width:2; stroke-dasharray:7 7; animation:hwFlow 1.1s linear infinite; }
.hw-dash-red { stroke:rgba(255,138,149,0.7); }
.hw-dash-green { stroke:rgba(61,214,140,0.8); }
.hw-star { filter:drop-shadow(0 0 6px rgba(255,214,107,0.9)); }
.hw-chassis { filter:drop-shadow(0 0 14px rgba(91,214,255,0.65)); animation:hwPulse 3.2s ease-in-out infinite; }
.hw-halo { animation:hwHaloPulse 3.2s ease-in-out infinite; transform-box:fill-box; transform-origin:center; }
@keyframes hwPulse { 0%,100%{ filter:drop-shadow(0 0 9px rgba(91,214,255,0.45)); } 50%{ filter:drop-shadow(0 0 18px rgba(91,214,255,0.85)); } }
@keyframes hwHaloPulse { 0%,100%{ opacity:0.75; transform:scale(0.96); } 50%{ opacity:1; transform:scale(1.04); } }
@keyframes hwFlow { to { stroke-dashoffset:-14; } }

.hw-chips { display:flex; gap:12px; flex-wrap:wrap; margin-bottom:28px; }
.hw-chip {
  font-size:13px; font-weight:600; color:var(--muted);
  background:var(--panel); border:1px solid var(--line); border-radius:999px;
  padding:9px 18px;
}
.hw-chip strong { color:#fff; font-weight:800; }
.hw-chip-gold { border-color:rgba(255,214,107,0.4); background:rgba(255,214,107,0.06); color:var(--gold-soft); }
.hw-chip-gold strong { color:var(--gold); }

.hw-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:14px; margin-bottom:36px; }
@media (max-width:1060px){ .hw-grid { grid-template-columns:repeat(2,1fr); } }
@media (max-width:620px){ .hw-grid { grid-template-columns:1fr; } }
.hw-benefit { display:grid; grid-template-columns:auto 1fr; gap:14px; align-items:start;
  background:var(--panel); border:1px solid var(--line); border-radius:12px; padding:16px; }
.hw-benefit .hw-ico { width:38px; height:38px; border-radius:9px; display:grid; place-items:center; background:rgba(255,255,255,0.10); color:#9DEBFF; flex:0 0 auto; }
.hw-benefit .hw-ico-xeon { background:transparent; padding:0; }
.hw-benefit .hw-ico-xeon img { width:38px; height:38px; border-radius:8px; display:block; }
.hw-benefit h4 { font-size:14.5px; font-weight:800; color:#fff; margin-bottom:3px; }
.hw-benefit p { font-size:13px; line-height:1.5; color:var(--muted); }
.hw-benefit-xeon { border-color:rgba(127,224,255,0.4); background:rgba(0,155,215,0.10); }

.brand-strip { display:flex; align-items:center; justify-content:center; gap:24px; flex-wrap:wrap; }
.brand-strip-label { font-size:12px; font-weight:700; letter-spacing:0.1em; text-transform:uppercase; color:var(--muted); }

/* =================== CTA / footer =================== */
.cta { background:linear-gradient(135deg,#00447C,#0078B4); color:#fff; padding:88px 0; text-align:center; }
.cta h2 { font-size:clamp(28px,4vw,46px); letter-spacing:-0.025em; margin-bottom:14px; font-weight:800; }
.cta p { font-size:17px; opacity:0.92; max-width:620px; margin:0 auto 32px; }
.cta-actions { display:flex; gap:16px; justify-content:center; flex-wrap:wrap; }
.cta-btn {
  display:inline-block; background:rgba(255,255,255,0.12); color:#fff; border:1px solid rgba(255,255,255,0.4);
  font-weight:800; font-size:16px; padding:14px 28px; border-radius:10px; text-decoration:none;
  transition:transform 0.15s ease, background 0.2s ease;
}
.cta-btn:hover { transform:translateY(-2px); background:rgba(255,255,255,0.2); }
.cta-btn-solid { background:#fff; color:#00447C; border-color:#fff; box-shadow:0 8px 24px rgba(0,0,0,0.18); }
.cta-btn-solid:hover { background:#fff; }
footer { padding:28px 0; color:var(--muted); font-size:13px; border-top:1px solid var(--line-soft); }
.footer-inner { display:flex; justify-content:space-between; align-items:center; gap:16px; flex-wrap:wrap; }
.footer-vp { display:flex; align-items:center; gap:8px; }

/* =================== responsive / reduced motion =================== */
@media (max-width:760px) {
  .container { padding:0 18px; }
  .chapter { padding:64px 0; }
  .hero { padding:72px 0 64px; }
  .ch-lede { font-size:15px; }
  .btn-group { width:100%; gap:8px; }
  .btn-group .ctrl-btn { flex:1 1 0; min-width:0; padding:12px 4px; font-size:13px; text-align:center; }
  .speed-group { flex:1 1 100%; }
  .speed-group .ctrl-btn { flex:1; }
  .qpicker-group { width:100%; margin-left:0; }
  .qpicker, .qpicker.qpicker-wide { min-width:0; flex:1; }
  .stats-bar .stat.savings { grid-column:1 / -1; }
  .cta-actions { flex-direction:column; align-items:stretch; }
  .cta-btn { width:100%; text-align:center; padding:15px 20px; }
  .problem-readout { gap:22px; flex-wrap:wrap; }
  .qc-text { font-size:15px; }
}
@media (max-width:420px) { .stats-bar { grid-template-columns:1fr; } .hero h1 { font-size:36px; } }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior:auto; }
  [data-reveal] { transition:none; opacity:1; transform:none; }
  .orb-a, .orb-b, .float-cube, .scroll-cue svg, .mini-cell, .b-dot, .b-ring,
  .hw-chassis, .hw-halo, .hw-dash, .step-chassis, .flow-line,
  .cube, .cube-gold, .wall-gold, .qc-text::after,
  .qpicker-menu, .qpicker-caret { animation:none !important; transition:none !important; }
  .kx-bar span, .cb-fill, .proof-caption { transition:none !important; }
}