/* Academy & Exam OS microsite — OsDot website family presentation.
   Token sources are recorded in docs/STEP_9B_MICROSITE_LOCAL_REVIEW.md §4.
   CONFIRMED = read from the live osdots.com theme CSS / logo pixels on 2026-09-26.
   DERIVED   = provisional values chosen for this review build (accessibility or layout). */

:root {
  /* CONFIRMED — osdots.com */
  --osd-charcoal: #2D2D2D;   /* --wd-primary-color; hero slider background; logo "Os" */
  --osd-bar: #2E2E2E;        /* header menu bar */
  --osd-green: #7AA754;      /* --btn-accented-bgcolor; header rule; logo "Dot" */
  --osd-lime: #A3CF3E;       /* hero headline emphasis and slider bullets */
  --osd-title: #242424;      /* --wd-title-color */
  --osd-text: #767676;       /* --wd-text-color */
  --osd-hover: #424242;      /* --btn-accented-bgcolor-hover */
  --osd-footer: #17172F;     /* .wd-footer background */
  --osd-radius-btn: 5px;     /* --btn-accented-brd-radius */
  --osd-container: 1222px;   /* --wd-container-w */
  --osd-font: "Outfit", "Segoe UI", system-ui, -apple-system, sans-serif; /* theme font for text, titles and header */

  /* DERIVED — provisional */
  --ink: var(--osd-title);
  --body: #484848;           /* body copy, 9.3:1 on white */
  --muted: #636363;          /* captions, 6.0:1 on white, 5.6:1 on --tint */
  --green-ink: #4E7A32;      /* green text/links on light surfaces, 5.1:1 on white */
  --tint: #F3F7EE;           /* pale-green section wash */
  --tint-2: #E8F0DF;         /* card wash */
  --line: #E1E6DC;           /* hairlines */
  --dark: var(--osd-charcoal);
  --dark-2: #232323;         /* exam-hall chapter */
  --on-dark: #FFFFFF;
  --on-dark-muted: #CFCFCF;  /* 8.9:1 on --dark */
  --line-dark: rgba(255, 255, 255, .14);
  --focus: var(--green-ink);
  --focus-on-dark: var(--osd-lime);
  --radius: 10px;
  --radius-lg: 16px;
  --shadow: 0 1px 2px rgba(0, 0, 0, .05), 0 10px 28px rgba(0, 0, 0, .07);
  --shadow-lg: 0 2px 6px rgba(0, 0, 0, .10), 0 28px 60px rgba(0, 0, 0, .22);
  --gutter: 24px;
}

/* ------------------------------------------------------------------ font: Outfit, self-hosted
   Upstream Outfitio/Outfit-Fonts @ 902773808eb3 fonts/variable/Outfit[wght].woff2 — SIL Open Font License 1.1 (assets/fonts/OFL.txt). */
@font-face {
  font-family: "Outfit";
  src: url("../fonts/Outfit-VariableFont_wght.woff2") format("woff2");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

/* ------------------------------------------------------------------ base */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 88px; }
body {
  margin: 0;
  background: #fff;
  color: var(--body);
  font-family: var(--osd-font);
  font-size: 17px;
  line-height: 1.65;
  font-weight: 400;
  overflow-x: clip;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--green-ink); text-underline-offset: .18em; }
a:hover { color: var(--osd-charcoal); }
h1, h2, h3, h4 { color: var(--ink); font-weight: 600; line-height: 1.15; margin: 0 0 .5em; letter-spacing: -.01em; }
h1 { font-size: clamp(2.1rem, 1.3rem + 3vw, 3.25rem); line-height: 1.08; }
h2 { font-size: clamp(1.75rem, 1.2rem + 1.9vw, 2.45rem); }
h3 { font-size: 1.3rem; line-height: 1.3; }
p { margin: 0 0 1em; }
ul, ol { padding-left: 1.2em; }
strong { color: var(--ink); font-weight: 600; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; border-radius: 4px; }
.band--dark :focus-visible, .hero :focus-visible, .site-footer :focus-visible, .storynav :focus-visible { outline-color: var(--focus-on-dark); }
.visually-hidden {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: 16px; top: -60px; z-index: 100; padding: 10px 16px;
  background: var(--osd-charcoal); color: #fff; border-radius: var(--osd-radius-btn); font-weight: 600;
}
.skip-link:focus { top: 12px; color: #fff; }
.container { width: 100%; max-width: var(--osd-container); margin: 0 auto; padding: 0 var(--gutter); }
.narrow { max-width: 780px; }

/* ------------------------------------------------------------------ type helpers */
.eyebrow {
  display: inline-block; margin: 0 0 14px; font-size: 13px; font-weight: 600;
  letter-spacing: .16em; text-transform: uppercase; color: var(--green-ink);
}
.band--dark .eyebrow, .hero .eyebrow { color: var(--osd-lime); }
.lead { font-size: 1.16rem; line-height: 1.6; color: var(--body); max-width: 60ch; }
.accent { color: var(--green-ink); }
.hero .accent, .band--dark .accent { color: var(--osd-lime); }
.muted { color: var(--muted); }
.small { font-size: .9rem; }

/* ------------------------------------------------------------------ buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 48px; padding: 12px 24px; border-radius: var(--osd-radius-btn);
  font: 600 16px/1.2 var(--osd-font); text-decoration: none; cursor: pointer;
  border: 2px solid transparent; transition: background-color .2s ease, color .2s ease, border-color .2s ease;
}
.btn .icon { width: 18px; height: 18px; }
/* Brand fill #7AA754 with the brand charcoal label (4.9:1). The live site's white label measures 2.8:1. */
.btn--primary { background: var(--osd-green); color: var(--osd-charcoal); }
.btn--primary:hover { background: var(--osd-hover); color: #fff; }
.btn--outline { border-color: var(--osd-charcoal); color: var(--osd-charcoal); background: transparent; }
.btn--outline:hover { background: var(--osd-charcoal); color: #fff; }
.btn--outline-light { border-color: #fff; color: #fff; background: transparent; }
.btn--outline-light:hover { background: #fff; color: var(--osd-charcoal); }
.btn--small { min-height: 40px; padding: 8px 18px; font-size: 15px; }
.btn-row { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.textlink { display: inline-flex; align-items: center; gap: 6px; font-weight: 600; text-decoration: none; color: var(--green-ink); }
.textlink:hover { text-decoration: underline; }
.textlink .icon { width: 18px; height: 18px; }
.hero .textlink, .band--dark .textlink { color: var(--osd-lime); }

/* ------------------------------------------------------------------ header */
.site-header { position: relative; z-index: 30; background: #fff; border-bottom: 4px solid var(--osd-green); }
.site-header__inner { display: flex; align-items: center; gap: 24px; min-height: 76px; }
.brand { display: flex; align-items: center; gap: 14px; flex: 0 0 auto; }
/* Two links: the OsDot logo opens osdots.com, the product name opens this site's home page.
   The block padding enlarges each touch target; the matching negative margin keeps the header layout unchanged. */
.brand a { display: flex; align-items: center; padding-block: 8px; margin-block: -8px; text-decoration: none; color: var(--ink); }
.brand img { width: 116px; height: auto; }
.brand__divider { width: 1px; height: 28px; background: var(--line); }
.brand__product { font-weight: 600; font-size: 17px; letter-spacing: -.005em; white-space: nowrap; }
.primary-nav { margin-left: auto; display: flex; align-items: center; }
.primary-nav ul { display: flex; align-items: center; gap: 6px; list-style: none; margin: 0; padding: 0; }
.primary-nav a {
  display: inline-flex; align-items: center; min-height: 44px; padding: 0 12px; border-radius: 4px;
  font-size: 13px; font-weight: 500; letter-spacing: .06em; text-transform: uppercase;
  color: var(--osd-charcoal); text-decoration: none;
}
.primary-nav a:hover { color: var(--green-ink); }
.primary-nav a[aria-current="page"] { color: var(--green-ink); box-shadow: inset 0 -2px 0 var(--osd-green); }
.primary-nav .nav-cta { margin-left: 10px; }
.primary-nav .nav-cta a { text-transform: none; letter-spacing: 0; font-size: 15px; font-weight: 600; padding: 0 20px; background: var(--osd-green); color: var(--osd-charcoal); border-radius: var(--osd-radius-btn); }
.primary-nav .nav-cta a:hover { background: var(--osd-hover); color: #fff; }
.primary-nav .nav-cta a[aria-current="page"] { box-shadow: none; }
/* OsDot social profiles: header row from 1100 px (after the Editions button), the menu drawer up to 900 px, and the footer. */
.nav-social, .footer-social { display: flex; align-items: center; gap: 2px; list-style: none; margin: 0; padding: 0; }
.social-link { display: inline-flex; align-items: center; justify-content: center; width: 36px; height: 36px; border-radius: 50%; color: var(--osd-charcoal); text-decoration: none; }
.social-link__icon { width: 18px; height: 18px; }
.primary-nav .nav-social { gap: 2px; margin-left: 16px; padding-left: 12px; border-left: 1px solid var(--line); }
.primary-nav .social-link { min-height: 36px; padding: 0; }
.primary-nav .social-link:hover { color: var(--green-ink); background: rgba(122, 167, 84, .14); }
@media (max-width: 1099px) { .primary-nav .nav-social { display: none; } }
.menu-toggle {
  display: none; margin-left: auto; align-items: center; gap: 8px; min-height: 44px; padding: 0 14px;
  border: 1px solid var(--line); border-radius: var(--osd-radius-btn); background: #fff; color: var(--osd-charcoal);
  font: 600 15px var(--osd-font); cursor: pointer;
}
.menu-toggle .icon { width: 20px; height: 20px; }

@media (max-width: 900px) {
  .js .menu-toggle { display: inline-flex; }
  .js .primary-nav { display: none; position: absolute; left: 0; right: 0; top: 100%; background: #fff; border-bottom: 4px solid var(--osd-green); box-shadow: var(--shadow); }
  .js .primary-nav.is-open { display: block; }
  .primary-nav ul { flex-direction: column; align-items: stretch; gap: 0; padding: 8px var(--gutter) 16px; }
  .primary-nav a { min-height: 48px; font-size: 14px; }
  .primary-nav .nav-cta { margin: 8px 0 0; }
  .primary-nav .nav-cta a { justify-content: center; min-height: 48px; }
  .js .primary-nav .nav-social { display: flex; flex-direction: row; gap: 8px; margin: 0 var(--gutter) 16px; padding: 12px 0 0; border-left: 0; border-top: 1px solid var(--line); }
  .js .primary-nav .social-link { width: 44px; height: 44px; min-height: 44px; }
  html:not(.js) .site-header__inner { flex-wrap: wrap; padding-bottom: 8px; }
  html:not(.js) .primary-nav { width: 100%; }
  html:not(.js) .primary-nav ul { flex-direction: row; flex-wrap: wrap; padding: 0; }
}
@media (max-width: 520px) {
  .site-header__inner { gap: 12px; }
  .brand { gap: 10px; }
  .brand img { width: 84px; }
  .brand__product { font-size: 14px; }
  .brand__divider { height: 22px; }
  .menu-toggle { padding: 0 10px; }
}
@media (max-width: 420px) {
  .menu-toggle__text { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
}

/* ------------------------------------------------------------------ bands */
.band { padding: clamp(64px, 5vw + 32px, 112px) 0; }
.band--tint { background: var(--tint); }
.band--dark { background: var(--dark); color: var(--on-dark-muted); }
.band--dark h2, .band--dark h3, .band--dark strong { color: #fff; }
.band--dark a:not(.btn) { color: var(--osd-lime); }
.band--tight { padding: 48px 0; }
.section-head { max-width: 760px; margin-bottom: 44px; }
.section-head--center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head--center .lead { margin-left: auto; margin-right: auto; }

/* ------------------------------------------------------------------ hero */
.hero { position: relative; overflow: hidden; background: var(--osd-charcoal); color: var(--on-dark-muted); padding: clamp(48px, 4vw + 24px, 88px) 0 clamp(56px, 5vw + 24px, 96px); }
.hero::before { /* the OsDot orb, drawn as a quiet ring and dot behind the devices */
  content: ""; position: absolute; width: min(78vw, 980px); aspect-ratio: 1; right: -18%; top: 50%; transform: translateY(-50%);
  border-radius: 50%; border: 2px solid rgba(255, 255, 255, .055); pointer-events: none;
}
.hero::after {
  content: ""; position: absolute; width: 22px; height: 22px; border-radius: 50%; background: var(--osd-green);
  right: calc(-18% + min(78vw, 980px) / 2 - 11px); top: calc(50% - min(78vw, 980px) / 2 - 11px); opacity: .55; pointer-events: none;
}
.hero__grid { position: relative; z-index: 1; display: grid; grid-template-columns: minmax(0, 5.3fr) minmax(0, 6fr); gap: clamp(28px, 4vw, 64px); align-items: center; }
.hero h1 { color: #fff; margin-bottom: 22px; font-size: clamp(2.05rem, 1.2rem + 2.5vw, 3rem); }
.hero .lead { color: var(--on-dark-muted); margin-bottom: 30px; }
.hero__more { margin-top: 22px; }
@media (max-width: 1023px) {
  .hero__grid { grid-template-columns: minmax(0, 1fr); }
  .hero::before { right: -45%; top: 72%; width: 150vw; }
  .hero::after { display: none; }
}

/* Device composition (neutral frames; the screens inside are unedited captures) */
.devices { position: relative; width: 100%; aspect-ratio: 1 / .86; margin: 0; }
.device { position: absolute; margin: 0; }
.device img { width: 100%; height: auto; }
.device--laptop { right: 0; top: 0; width: 80%; }
.device--laptop .device__screen { background: #151515; border-radius: 14px 14px 0 0; padding: 2.1% 2.1% 2.6%; box-shadow: var(--shadow-lg); }
.device--laptop .device__screen img { border-radius: 3px; }
.device--laptop .device__base { height: 0; padding-top: 3.4%; margin: 0 -6.5%; background: linear-gradient(#d9dbde, #a9adb3); border-radius: 0 0 14px 14px / 0 0 60% 60%; position: relative; }
.device--laptop .device__base::after { content: ""; position: absolute; left: 42%; right: 42%; top: 0; height: 35%; background: #8e9298; border-radius: 0 0 8px 8px; }
.device--tablet { left: 0; bottom: 2.5%; width: 58%; z-index: 2; }
.device--tablet .device__screen { background: #121212; border-radius: 22px; padding: 3.2%; box-shadow: var(--shadow-lg); }
.device--tablet .device__screen img { border-radius: 6px; }
.device--phone { right: 3%; bottom: 0; width: 19.5%; z-index: 3; }
.device--phone .device__screen { background: #121212; border-radius: 26px; padding: 5.5% 5%; box-shadow: var(--shadow-lg); }
.device--phone .device__screen img { border-radius: 14px; }
/* decoration only: a few pixels of depth on fine pointers (set by site.js; never under reduced motion) */
.device { transition: transform .35s ease-out; }
.device--laptop { transform: translate(calc(var(--tx, 0px) * -.6), calc(var(--ty, 0px) * -.6)); }
.device--tablet { transform: translate(var(--tx, 0px), var(--ty, 0px)); }
.device--phone { transform: translate(calc(var(--tx, 0px) * 1.6), calc(var(--ty, 0px) * 1.6)); }
.phone--center .phone__frame { margin: 0 auto; }
.devices__caption { margin-top: 18px; font-size: .88rem; color: var(--on-dark-muted); max-width: 62ch; }
@media (max-width: 640px) {
  .devices { aspect-ratio: 1 / .8; }
  .device--laptop { display: none; }
  .device--tablet { width: 84%; top: 0; bottom: auto; }
  .device--phone { width: 27%; right: 0; }
}

/* ------------------------------------------------------------------ capability strip */
.capstrip { background: #fff; border-bottom: 1px solid var(--line); }
.capstrip ul { list-style: none; margin: 0; padding: 18px 0; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px 28px; }
.capstrip li { display: flex; align-items: center; gap: 10px; font-size: 15px; font-weight: 500; color: var(--ink); }
.capstrip .icon { width: 22px; height: 22px; color: var(--green-ink); flex: 0 0 auto; }
@media (max-width: 900px) { .capstrip ul { justify-content: flex-start; } .capstrip li { width: calc(50% - 14px); } }
@media (max-width: 520px) { .capstrip li { width: 100%; } }

/* ------------------------------------------------------------------ cards and grids */
.grid { display: grid; gap: 24px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
@media (max-width: 1023px) { .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 640px) { .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); } }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; box-shadow: 0 1px 2px rgba(0, 0, 0, .04); }
.card h3 { margin-bottom: .4em; }
.card p:last-child, .card ul:last-child { margin-bottom: 0; }
.card__icon { display: inline-flex; align-items: center; justify-content: center; width: 44px; height: 44px; border-radius: 8px; background: var(--tint-2); color: var(--green-ink); margin-bottom: 16px; }
.card__icon .icon { width: 24px; height: 24px; }
.band--tint .card { border-color: #dfe7d6; }
.ticks { list-style: none; padding: 0; margin: 0 0 1em; }
.ticks li { position: relative; padding-left: 30px; margin-bottom: 10px; }
.ticks li::before { content: ""; position: absolute; left: 2px; top: .45em; width: 16px; height: 9px; border-left: 2.5px solid var(--green-ink); border-bottom: 2.5px solid var(--green-ink); transform: rotate(-45deg); }
.band--dark .ticks li::before { border-color: var(--osd-lime); }
.note {
  display: flex; gap: 12px; align-items: flex-start; padding: 14px 18px; border-radius: 8px;
  background: #fff; border: 1px solid var(--line); border-left: 4px solid var(--osd-green); font-size: .95rem; color: var(--body);
}
.note .icon { width: 20px; height: 20px; color: var(--green-ink); flex: 0 0 auto; margin-top: 3px; }
.band--dark .note { background: rgba(255, 255, 255, .04); border-color: var(--line-dark); border-left-color: var(--osd-lime); color: var(--on-dark-muted); }
.band--dark .note .icon { color: var(--osd-lime); }
.pending { color: var(--muted); }
.pending__label { font-weight: 600; color: var(--ink); }
.band--dark .pending, .site-footer .pending { color: var(--on-dark-muted); }
.band--dark .pending__label, .site-footer .pending__label { color: #fff; }

/* ------------------------------------------------------------------ product screens */
.shot { margin: 0; }
.shot__frame { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); background: #fff; box-shadow: var(--shadow); }
.band--dark .shot__frame { border-color: #3a3a3a; box-shadow: 0 24px 60px rgba(0, 0, 0, .45); }
.shot figcaption, .phone figcaption { margin-top: 12px; font-size: .9rem; line-height: 1.5; color: var(--muted); }
.band--dark .shot figcaption, .band--dark .phone figcaption { color: var(--on-dark-muted); }
.phone { margin: 0; }
.phone__frame { background: #121212; border-radius: 30px; padding: 11px 10px; box-shadow: var(--shadow); max-width: 280px; }
.phone__frame img { border-radius: 20px; }
.phones { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 28px 24px; align-items: start; }
.phones .phone__frame { max-width: 240px; }
.surface { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--green-ink); }
.band--dark .surface { color: var(--osd-lime); }

/* ------------------------------------------------------------------ story chapters */
.chapter { position: relative; }
.chapter__num {
  display: inline-flex; align-items: center; justify-content: center; min-width: 46px; height: 40px; padding: 0 10px; margin-bottom: 18px;
  border-radius: 6px; background: var(--osd-green); color: var(--osd-charcoal); font-weight: 600; font-size: 16px; letter-spacing: .02em;
}
.band--dark .chapter__num { background: var(--osd-lime); }
.split { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: clamp(28px, 4vw, 64px); align-items: start; }
.split--flip { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.split--flip > :first-child { order: 2; }
.split__text { position: sticky; top: 110px; }
@media (max-width: 1023px) {
  .split, .split--flip { grid-template-columns: minmax(0, 1fr); }
  .split--flip > :first-child { order: 0; }
  .split__text { position: static; }
}
.stack { display: grid; gap: 32px; }
.shot-pair { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
@media (max-width: 640px) { .shot-pair { grid-template-columns: 1fr; } }
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin: 28px 0 0; padding: 0; list-style: none; }
.facts li { padding: 16px 18px; border-radius: 8px; background: #fff; border: 1px solid var(--line); font-size: .95rem; }
.band--tint .facts li { border-color: #dfe7d6; }
.facts strong { display: block; margin-bottom: 2px; }
.chapter-end { margin-top: 36px; display: flex; flex-wrap: wrap; gap: 12px 28px; align-items: center; }

/* ------------------------------------------------------------------ story navigation (palette rail + clock) */
.storynav { margin: 0 0 40px; }
.storynav__clock { display: none; }
.storynav ol { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 8px 20px; }
.storynav a { display: flex; align-items: center; gap: 12px; min-height: 44px; text-decoration: none; color: var(--ink); font-weight: 500; }
.storynav__cell {
  display: inline-flex; align-items: center; justify-content: center; flex: 0 0 auto; width: 38px; height: 34px; border-radius: 6px;
  border: 1.5px dashed #b9c2b0; background: #fff; color: var(--ink); font-size: 14px; font-weight: 600;
}
.storynav__title { font-size: 15px; }
.storynav .is-visited .storynav__cell { border-style: solid; border-color: var(--osd-green); background: var(--osd-green); color: var(--osd-charcoal); }
.storynav .is-current .storynav__cell { box-shadow: 0 0 0 2px #fff, 0 0 0 4px var(--osd-charcoal); border-style: solid; }

@media (min-width: 1400px) {
  .js .storynav {
    position: fixed; z-index: 20; right: 18px; top: 50%; transform: translateY(-50%); margin: 0; padding: 12px 10px;
    background: rgba(45, 45, 45, .96); border-radius: 12px; box-shadow: var(--shadow-lg); width: 70px;
    opacity: 0; visibility: hidden; transition: opacity .25s ease, visibility .25s ease;
  }
  .js .storynav.is-visible { opacity: 1; visibility: visible; }
  .js .storynav__clock { display: block; text-align: center; color: #fff; margin-bottom: 10px; }
  .js .storynav__clock .icon { width: 18px; height: 18px; color: var(--osd-lime); margin: 0 auto 2px; display: block; }
  .js .storynav__time { display: block; font-size: 14px; font-weight: 600; font-variant-numeric: tabular-nums; line-height: 1.2; }
  .js .storynav__time.is-done { font-size: 11px; color: var(--osd-lime); letter-spacing: .02em; }
  .js .storynav ol { grid-template-columns: 1fr; gap: 6px; justify-items: center; }
  .js .storynav a { min-height: 0; position: relative; }
  .js .storynav__cell { width: 44px; height: 34px; border-color: rgba(255, 255, 255, .35); background: transparent; color: #fff; }
  .js .storynav .is-visited .storynav__cell { background: var(--osd-green); border-color: var(--osd-green); color: var(--osd-charcoal); }
  .js .storynav .is-current .storynav__cell { box-shadow: 0 0 0 2px var(--osd-charcoal), 0 0 0 4px var(--osd-lime); }
  .js .storynav__title {
    position: absolute; right: calc(100% + 14px); top: 50%; transform: translateY(-50%); white-space: nowrap;
    background: var(--osd-charcoal); color: #fff; padding: 6px 12px; border-radius: 6px; font-size: 14px;
    opacity: 0; pointer-events: none; transition: opacity .15s ease;
  }
  .js .storynav a:hover .storynav__title, .js .storynav a:focus-visible .storynav__title { opacity: 1; }
}
@media (max-width: 1399px) {
  .js .storynav { display: none; }
}
.storybar { display: none; }
@media (max-width: 1399px) {
  .js .storybar {
    display: flex; position: sticky; top: 0; z-index: 25; align-items: center; gap: 12px; min-height: 52px; padding: 6px var(--gutter);
    background: var(--osd-charcoal); color: #fff; border-bottom: 3px solid var(--osd-green);
  }
  .js .storybar[hidden] { display: none; }
}
.storybar__label { flex: 1 1 auto; min-width: 0; font-weight: 600; font-size: 15px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.storybar__num { color: var(--osd-lime); margin-right: 8px; }
.storybar__time { font-variant-numeric: tabular-nums; font-size: 14px; color: var(--on-dark-muted); display: inline-flex; align-items: center; gap: 6px; }
.storybar__time .icon { width: 16px; height: 16px; color: var(--osd-lime); }
.storybar details { position: relative; }
.storybar summary {
  list-style: none; cursor: pointer; display: inline-flex; align-items: center; min-height: 40px; padding: 0 14px;
  border: 1.5px solid rgba(255, 255, 255, .5); border-radius: var(--osd-radius-btn); font-weight: 600; font-size: 14px;
}
.storybar summary::-webkit-details-marker { display: none; }
.storybar details ol {
  position: absolute; right: 0; top: calc(100% + 8px); width: min(320px, 86vw); max-height: 70vh; overflow: auto;
  list-style: none; margin: 0; padding: 8px; background: #fff; border-radius: 10px; box-shadow: var(--shadow-lg);
}
.storybar details a { display: flex; gap: 10px; align-items: center; min-height: 44px; padding: 0 10px; border-radius: 6px; color: var(--ink); text-decoration: none; }
.storybar details a:hover { background: var(--tint); }
.storybar details a span:first-child { font-weight: 600; color: var(--green-ink); min-width: 28px; }

/* ------------------------------------------------------------------ exam stage (chapter 04) */
.band--exam { background: var(--dark-2); }
.stage { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 4fr); gap: clamp(28px, 4vw, 60px); margin-top: 20px; }
.stage__visual { display: none; }
.stage__steps { list-style: none; margin: 0; padding: 0; display: grid; gap: 48px; }
.step h3 { color: #fff; }
.step__time { display: inline-flex; align-items: center; gap: 8px; margin-bottom: 10px; font-size: 14px; font-weight: 600; color: var(--osd-lime); font-variant-numeric: tabular-nums; }
.step__time .icon { width: 16px; height: 16px; }
.step .shot { margin-top: 18px; }
.stage { grid-template-columns: 1fr; }
.stage.is-enhanced { grid-template-columns: minmax(0, 7fr) minmax(0, 4fr); }
.stage.is-enhanced .stage__visual { display: block; }
.stage.is-enhanced .stage__sticky { position: sticky; top: 90px; }
.stage.is-enhanced .step { min-height: 48vh; display: flex; flex-direction: column; justify-content: center; opacity: .45; transition: opacity .3s ease; }
.stage.is-enhanced .step.is-active { opacity: 1; }
.stage.is-enhanced .step .shot { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); margin: 0; }
.step__more { font-size: .95rem; color: var(--on-dark-muted); border-left: 3px solid var(--osd-lime); padding-left: 12px; }
/* two-screen stage: without pinning the screens stay a readable size and the chapter stays short */
.stage:not(.is-enhanced) .step .shot { max-width: 920px; }
.stage__sticky .shot__frame img { transition: opacity .25s ease; }
.stage__sticky .shot__frame.is-swapping img { opacity: .15; }
.stage__progress { display: flex; gap: 6px; margin-top: 16px; }
.stage__progress span { flex: 1 1 0; height: 4px; border-radius: 2px; background: rgba(255, 255, 255, .16); }
.stage__progress span.is-done { background: var(--osd-lime); }

/* ------------------------------------------------------------------ brand swap comparator */
.swap { margin: 0; }
.swap__stage { position: relative; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); box-shadow: var(--shadow); background: #fff; }
.swap__stage img { width: 100%; }
.swap__after { position: absolute; inset: 0; clip-path: inset(0 0 0 var(--pos, 50%)); }
.swap__after img { width: 100%; height: 100%; object-fit: cover; }
.swap__line { position: absolute; top: 0; bottom: 0; left: var(--pos, 50%); width: 0; border-left: 3px solid #fff; box-shadow: 0 0 0 1px rgba(0, 0, 0, .25); pointer-events: none; }
.swap__line::after { content: ""; position: absolute; top: 50%; left: -19px; width: 34px; height: 34px; border-radius: 50%; background: #fff; box-shadow: 0 2px 8px rgba(0, 0, 0, .35); transform: translateY(-50%); }
.swap__tag { position: absolute; bottom: 12px; padding: 4px 10px; border-radius: 4px; background: rgba(45, 45, 45, .88); color: #fff; font-size: 13px; font-weight: 600; pointer-events: none; }
.swap__tag--before { left: 12px; }
.swap__tag--after { right: 12px; }
.swap__controls { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 18px; margin-top: 18px; }
.swap__controls label { font-weight: 600; color: var(--ink); }
.swap__range { flex: 1 1 260px; accent-color: var(--osd-green); min-height: 44px; }
.swap__static { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.swap.is-enhanced .swap__static { display: none; }
.swap:not(.is-enhanced) .swap__interactive { display: none; }
@media (max-width: 640px) { .swap__static { grid-template-columns: 1fr; } }
.swap-phones { display: grid; grid-template-columns: repeat(2, minmax(0, 220px)); gap: 24px; justify-content: start; margin-top: 36px; }

/* ------------------------------------------------------------------ editions shelf */
.shelf { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
@media (max-width: 1023px) {
  /* without JavaScript the cards stack; the horizontal shelf with its prev/next buttons is an enhancement */
  .shelf { grid-template-columns: minmax(0, 1fr); }
  .js .shelf { grid-auto-flow: column; grid-template-columns: none; grid-auto-columns: min(84%, 380px); overflow-x: auto; scroll-snap-type: x mandatory; padding-bottom: 12px; }
  .js .shelf > * { scroll-snap-align: start; }
}
.edition { display: flex; flex-direction: column; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; box-shadow: var(--shadow); }
.edition--dark { background: var(--osd-charcoal); border-color: var(--osd-charcoal); color: var(--on-dark-muted); }
.edition--dark h3, .edition--dark strong { color: #fff; }
.edition--dark .ticks li::before { border-color: var(--osd-lime); }
.edition__kicker { font-size: 13px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--green-ink); margin: 0 0 8px; }
.edition--dark .edition__kicker { color: var(--osd-lime); }
.edition__meta { display: flex; flex-wrap: wrap; gap: 8px; margin: 6px 0 18px; }
.chip { display: inline-flex; align-items: center; min-height: 28px; padding: 2px 12px; border-radius: 999px; font-size: 13px; font-weight: 600; background: var(--tint-2); color: var(--ink); }
.edition--dark .chip { background: rgba(255, 255, 255, .1); color: #fff; }
.shelf-nav { display: none; gap: 10px; margin-top: 14px; }
@media (max-width: 1023px) { .js .shelf-nav { display: flex; } }
.shelf-nav button { min-width: 44px; min-height: 44px; border-radius: var(--osd-radius-btn); border: 1.5px solid var(--osd-charcoal); background: #fff; cursor: pointer; font: 600 15px var(--osd-font); color: var(--osd-charcoal); }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
table { width: 100%; border-collapse: collapse; font-size: .95rem; }
th, td { text-align: left; vertical-align: top; padding: 14px 16px; border-bottom: 1px solid var(--line); }
thead th { background: var(--tint); color: var(--ink); font-weight: 600; }
tbody th { color: var(--ink); font-weight: 600; }
tr:last-child th, tr:last-child td { border-bottom: 0; }
.tree {
  margin: 0; padding: 22px 24px; border-radius: var(--radius); background: var(--osd-charcoal); color: #e6e6e6;
  font: 14px/1.75 ui-monospace, "Cascadia Mono", Consolas, monospace; overflow-x: auto; white-space: pre;
}
.tree b { color: var(--osd-lime); font-weight: 600; }
.tree i { color: #a9a9a9; font-style: normal; }

/* price, contents and terms of a licence card (commercial model, owner decision 2026-09-26) */
.edition__price { margin: 4px 0 16px; display: flex; align-items: baseline; gap: 8px; }
.edition__amount { font-size: 2.6rem; font-weight: 600; line-height: 1; color: var(--ink); letter-spacing: -.02em; }
.edition--dark .edition__amount { color: #fff; }
.edition__term { font-size: 15px; color: var(--muted); }
.edition--dark .edition__term { color: var(--on-dark-muted); }
.included { list-style: none; margin: 0 0 18px; padding: 14px 0 0; border-top: 1px solid var(--line); display: grid; gap: 8px; }
.edition--dark .included { border-top-color: var(--line-dark); }
.included li { position: relative; padding-left: 30px; }
.included li::before { content: ""; position: absolute; left: 0; top: .2em; width: 20px; height: 20px; border-radius: 50%; background: var(--osd-green); }
.included li::after { content: ""; position: absolute; left: 6px; top: .52em; width: 8px; height: 5px; border-left: 2px solid var(--osd-charcoal); border-bottom: 2px solid var(--osd-charcoal); transform: rotate(-45deg); }
.edition--dark .included li::before { background: var(--osd-lime); }
.edition__terms { margin-top: auto; padding-top: 14px; border-top: 1px solid var(--line); }
.edition--dark .edition__terms { border-top-color: var(--line-dark); }
.edition__terms-title { font-size: 13px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); margin: 0 0 8px; }
.edition--dark .edition__terms-title { color: var(--on-dark-muted); }
.chip--optional { background: var(--osd-charcoal); color: #fff; letter-spacing: .06em; }
.support-option { display: flex; flex-direction: column; }
.support-option .edition__buy { margin-top: auto; }
/* purchase button at the foot of each licence card */
.edition__buy { margin: 18px 0 0; }
.edition__buy .btn { width: 100%; }

/* ------------------------------------------------------------------ demo logins */
.demo-cards { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
@media (max-width: 1023px) { .demo-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 640px) { .demo-cards { grid-template-columns: minmax(0, 1fr); } }
.demo-card { display: flex; flex-direction: column; background: #fff; border: 1px solid #dfe7d6; border-top: 4px solid var(--osd-green); border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); }
.demo-card h3 { margin-bottom: .3em; }
.demo-card__creds { margin: 8px 0 20px; display: grid; gap: 10px; }
.demo-card__creds div { display: grid; gap: 2px; }
.demo-card__creds dt { font-size: 13px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.demo-card__creds dd { margin: 0; }
.demo-card__value { display: block; padding: 8px 12px; border-radius: 6px; background: var(--tint); border: 1px solid var(--line); color: var(--ink); font: 500 15px/1.4 ui-monospace, "Cascadia Mono", Consolas, monospace; overflow-wrap: anywhere; user-select: all; }
.demo-card__button { margin-top: auto; }
.demo-card__pending { display: flex; gap: 10px; align-items: flex-start; margin: auto 0 0; padding: 10px 12px; border-radius: 6px; background: var(--tint); border: 1px dashed #c9d4be; color: var(--muted); font-size: 15px; }
.demo-card__pending .icon { width: 18px; height: 18px; flex: 0 0 auto; margin-top: 2px; color: var(--green-ink); }

/* ------------------------------------------------------------------ FAQ */
.faq { display: grid; gap: 12px; }
.faq details { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.faq summary {
  cursor: pointer; list-style: none; display: flex; justify-content: space-between; gap: 16px; align-items: center;
  padding: 18px 22px; min-height: 44px; font-weight: 600; color: var(--ink); font-size: 1.05rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-size: 24px; line-height: 1; color: var(--green-ink); flex: 0 0 auto; }
.faq details[open] summary::after { content: "−"; }
.faq .faq__answer { padding: 0 22px 20px; }
.faq .faq__answer p:last-child { margin-bottom: 0; }
.faq-group { margin-top: 48px; }
.faq-group:first-child { margin-top: 0; }

/* ------------------------------------------------------------------ final CTA + page heads */
.submit { text-align: center; }
.submit .btn-row { justify-content: center; }
.submit__clock { display: inline-flex; align-items: center; gap: 10px; padding: 8px 16px; border-radius: 999px; border: 1.5px solid var(--osd-lime); color: var(--osd-lime); font-weight: 600; margin-bottom: 22px; }
.submit__clock .icon { width: 18px; height: 18px; }
.page-head { background: var(--osd-charcoal); color: var(--on-dark-muted); padding: clamp(48px, 4vw + 20px, 80px) 0; position: relative; overflow: hidden; }
.page-head h1 { color: #fff; font-size: clamp(2rem, 1.3rem + 2.4vw, 2.9rem); }
.page-head .lead { color: var(--on-dark-muted); }
.page-head::before { content: ""; position: absolute; width: 620px; aspect-ratio: 1; right: -180px; top: -260px; border-radius: 50%; border: 2px solid rgba(255, 255, 255, .055); }
.breadcrumb { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; padding: 0; margin: 0 0 18px; font-size: 14px; }
.breadcrumb li + li::before { content: "/"; margin-right: 6px; color: #8d8d8d; }
.breadcrumb a { color: var(--osd-lime); }
.breadcrumb [aria-current] { color: var(--on-dark-muted); }
.toc { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; list-style: none; padding: 0; }
.toc a { display: inline-flex; align-items: center; min-height: 40px; padding: 0 14px; border-radius: 999px; border: 1.5px solid rgba(255, 255, 255, .35); color: #fff; text-decoration: none; font-size: 14px; font-weight: 500; }
.toc a:hover { border-color: var(--osd-lime); color: var(--osd-lime); }
.status-table td:first-child { font-weight: 600; color: var(--ink); white-space: nowrap; }
.state { display: inline-flex; align-items: center; gap: 6px; font-weight: 600; }
.state::before { content: ""; width: 10px; height: 10px; border-radius: 50%; background: currentColor; }
.state--yes { color: var(--green-ink); }
.state--no { color: #8a5a00; }
.state--na { color: var(--muted); }

/* ------------------------------------------------------------------ footer */
.site-footer { background: var(--osd-footer); color: #c8c8d6; padding: 64px 0 0; font-size: 15px; }
.site-footer a { color: #fff; text-decoration: none; }
.site-footer a:hover { color: var(--osd-lime); text-decoration: underline; }
.site-footer__grid { display: grid; grid-template-columns: minmax(0, 1.5fr) repeat(3, minmax(0, 1fr)); gap: 40px; }
.site-footer img { width: 150px; margin-bottom: 18px; }
.site-footer h2 { font-size: 14px; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; color: #fff; margin-bottom: 14px; }
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer li { margin-bottom: 10px; }
.footer-social__label { margin: 22px 0 10px; font-size: 14px; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; color: #fff; }
.footer-social { gap: 10px; flex-wrap: wrap; }
.site-footer .footer-social li { margin: 0; }
.site-footer .social-link { width: 40px; height: 40px; color: #fff; border: 1px solid rgba(255, 255, 255, .28); }
.site-footer .social-link:hover { color: var(--osd-charcoal); background: var(--osd-lime); border-color: var(--osd-lime); text-decoration: none; }
.site-footer__legal { margin-top: 48px; padding: 20px 0 24px; border-top: 1px solid rgba(255, 255, 255, .12); display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; font-size: 14px; color: #a9a9bd; }
@media (max-width: 900px) { .site-footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 520px) { .site-footer__grid { grid-template-columns: 1fr; } }

/* ------------------------------------------------------------------ motion preferences */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; scroll-behavior: auto !important; }
}
@media print {
  .storynav, .storybar, .site-header nav, .menu-toggle { display: none !important; }
}