/**
 * Intaglio — stylesheet.
 *
 * Two layouts live here and they are deliberately unlike each other:
 *
 *  1. THE PLANE (front page). No page scroll, no header band, no stack of
 *     sections. A fixed viewport, regions placed in world coordinates, and a
 *     magnification rail down one edge. Everything is positioned by JS.
 *
 *  2. THE DOCUMENT (every other template). A normal, quiet, readable page —
 *     because a security printer still has to publish specifications that
 *     people print out and read. It borrows the plane's ink and rules, not
 *     its navigation.
 *
 * The plane styles are all scoped under `.is-plane`, a class this theme's
 * JavaScript adds. Without JS the same markup stays in normal flow and the
 * front page reads as an ordinary document — which is also what a crawler
 * sees.
 */

/* ---- Reset ---------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; }
img, svg, canvas, video { max-width: 100%; height: auto; display: block; }
button, input, select, textarea { font: inherit; color: inherit; }
a { color: inherit; }

/* ---- Tokens ---------------------------------------------------------- */

:root {
	/* One type scale, base 16 x 1.25, reused everywhere. */
	--itg-t-xs: 0.7rem;
	--itg-t-s: 0.8125rem;
	--itg-t-m: 1rem;
	--itg-t-l: 1.25rem;
	--itg-t-xl: 1.5625rem;
	--itg-t-2xl: 1.953rem;
	--itg-t-3xl: 2.441rem;
	--itg-t-4xl: 3.05rem;

	/* 4px base. */
	--itg-sp-1: 0.25rem;
	--itg-sp-2: 0.5rem;
	--itg-sp-3: 1rem;
	--itg-sp-4: 1.5rem;
	--itg-sp-5: 2.5rem;
	--itg-sp-6: 4rem;
	--itg-sp-7: 6rem;

	--itg-ff-text: "Spectral", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
	--itg-ff-ui: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
	--itg-ff-data: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

	--itg-ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

body {
	background: var( --itg-paper );
	color: var( --itg-ink );
	font-family: var( --itg-ff-text );
	font-size: var( --itg-t-m );
	line-height: 1.55;
	/* Security paper is sized and faintly speckled, never optically white. */
	background-image:
		radial-gradient( circle at 20% 30%, rgba( 19,26,23,0.020 ) 0 1px, transparent 1px ),
		radial-gradient( circle at 70% 65%, rgba( 19,26,23,0.016 ) 0 1px, transparent 1px );
	background-size: 7px 7px, 11px 11px;
}

.label {
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.14em;
	text-transform: uppercase;
	color: var( --itg-ink-faint );
}
.figure { font-family: var( --itg-ff-data ); font-variant-numeric: tabular-nums; }
.muted { color: var( --itg-ink-soft ); }

.skip-link {
	position: absolute; left: -9999px; top: 0; z-index: 100;
	background: var( --itg-ink ); color: var( --itg-paper );
	padding: var( --itg-sp-2 ) var( --itg-sp-3 );
}
.skip-link:focus { left: 0; }

:where( a, button, input, textarea, select, [tabindex] ):focus-visible {
	outline: 2px solid var( --itg-green );
	outline-offset: 2px;
}

/* ---- 1. THE SPECIMEN PANEL ------------------------------------------- */

/*
 * The plane is a SECTION, not the site. It lives in a bounded, fixed-height
 * panel and the page scrolls normally around it. An earlier version made it
 * `position: fixed; inset: 0` and took over the whole viewport: striking, and
 * unsellable — no navigation, no route to an enquiry, and nothing a buyer
 * could add a section to.
 */

.plane {
	position: relative;
	height: clamp( 30rem, 66vh, 42rem );
	border: 1px solid var( --itg-rule );
	background: var( --itg-paper-2 );
	overflow: hidden;
}

.plane.is-plane .plane-viewport {
	position: absolute;
	inset: 0;
	cursor: grab;
	touch-action: pan-y;
}
.plane.is-plane.is-engaged .plane-viewport { touch-action: none; }
.plane.is-plane .plane-viewport.is-dragging { cursor: grabbing; }

.plane.is-plane .region {
	position: absolute;
	left: 0;
	top: 0;
	transform-origin: 50% 50%;
	will-change: transform, opacity;
	visibility: hidden;
	opacity: 0;
}

/* Without JS the panel stops being a panel: it releases its height and the
   regions read as an ordinary stack, so content is never trapped inside a
   box that cannot scroll. */
.plane:not(.is-plane) {
	height: auto;
	border: 0;
	background: none;
	overflow: visible;
}
.plane:not(.is-plane) .plane-viewport { max-width: 46rem; margin: 0 auto; }
.plane:not(.is-plane) .region + .region {
	margin-top: var( --itg-sp-5 );
	padding-top: var( --itg-sp-4 );
	border-top: 1px solid var( --itg-rule );
}
.plane:not(.is-plane) .plane-rail,
.plane:not(.is-plane) .plane-hint,
.plane:not(.is-plane) .plane-readout { display: none; }

.plane-field { position: absolute; inset: 0; pointer-events: none; z-index: 0; }
.plane-field canvas { width: 100%; height: 100%; display: block; }
.plane.is-plane .plane-viewport > * { z-index: 1; }

/* --- the instrument chrome, scoped to the panel --- */

.plane-rail {
	position: absolute;
	background: color-mix( in srgb, var( --itg-paper-2 ) 93%, transparent );
	backdrop-filter: blur( 5px );
	left: var( --itg-sp-3 );
	top: 50%;
	transform: translateY( -50% );
	z-index: 12;
	display: flex;
	flex-direction: column;
	gap: var( --itg-sp-2 );
	align-items: flex-start;
	padding: var( --itg-sp-3 ) var( --itg-sp-3 ) var( --itg-sp-3 ) 0;
}
.plane-rail::before {
	content: "";
	position: absolute;
	left: 0.42rem; top: 0; bottom: 0;
	width: 1px;
	background: var( --itg-rule );
}
.plane-rail button {
	appearance: none;
	background: none;
	border: 0;
	padding: 0.2rem 0 0.2rem 1.35rem;
	position: relative;
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.1em;
	color: var( --itg-ink-faint );
	cursor: pointer;
	text-align: left;
	transition: color 180ms var( --itg-ease );
}
.plane-rail .rail-label { margin-left: 0.9rem; }
.plane-rail button::before {
	content: "";
	position: absolute;
	left: 0; top: 50%;
	width: 0.85rem; height: 1px;
	background: var( --itg-rule );
	transform: translateY( -50% );
	transition: width 200ms var( --itg-ease ), background 200ms var( --itg-ease );
}
.plane-rail button:hover { color: var( --itg-ink ); }
.plane-rail button[aria-current="true"] { color: var( --itg-green ); }
.plane-rail button[aria-current="true"]::before { width: 1.5rem; background: var( --itg-green ); }

.plane-readout {
	position: absolute;
	right: var( --itg-sp-3 );
	top: var( --itg-sp-3 );
	z-index: 12;
	background: color-mix( in srgb, var( --itg-paper-2 ) 93%, transparent );
	backdrop-filter: blur( 5px );
	padding: 0 0 0 var( --itg-sp-2 );
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-l );
	font-variant-numeric: tabular-nums;
	color: var( --itg-ink );
	text-align: right;
}
.plane-readout small {
	display: block;
	font-size: var( --itg-t-xs );
	letter-spacing: 0.14em;
	text-transform: uppercase;
	color: var( --itg-ink-faint );
}

/* Until the panel is engaged it says so, so nobody wonders why the wheel
   scrolls the page instead of magnifying. */
.plane-hint {
	position: absolute;
	left: 50%;
	bottom: var( --itg-sp-3 );
	transform: translateX( -50% );
	z-index: 12;
	margin: 0;
	padding: 0.45em 0.9em;
	background: var( --itg-ink );
	color: var( --itg-paper );
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.12em;
	text-transform: uppercase;
	transition: opacity 200ms var( --itg-ease );
}
.plane.is-engaged .plane-hint { opacity: 0; }

/* --- region content --- */

.region { width: 30rem; max-width: 86%; }
.region--wide { width: 38rem; }
.region--narrow { width: 19rem; }

.region h1, .region h2, .region h3 {
	font-family: var( --itg-ff-text );
	font-weight: 400;
	line-height: 1.14;
	margin: 0 0 var( --itg-sp-3 );
	text-wrap: balance;
}
.region h1 { font-size: var( --itg-t-2xl ); }
.region h2 { font-size: var( --itg-t-xl ); }
.region h3 { font-size: var( --itg-t-l ); }
.region p { margin: 0 0 var( --itg-sp-3 ); max-width: 58ch; }
.region p:last-child { margin-bottom: 0; }

.doc-frame {
	border: 1px solid var( --itg-rule );
	padding: var( --itg-sp-4 );
	background: var( --itg-paper );
	position: relative;
}
/* The plate mark: the debossed rectangle an intaglio plate leaves in paper. */
.doc-frame::before {
	content: "";
	position: absolute;
	inset: 0.5rem;
	border: 1px solid color-mix( in srgb, var( --itg-rule ) 60%, transparent );
	pointer-events: none;
}

.feature-panel {
	border-top: 2px solid var( --itg-ink );
	padding: var( --itg-sp-3 );
	background: var( --itg-paper );
	border-right: 1px solid var( --itg-rule );
	border-bottom: 1px solid var( --itg-rule );
	border-left: 1px solid var( --itg-rule );
}
.feature-panel .label { color: var( --itg-green ); }

.spec-row {
	display: grid;
	grid-template-columns: 9rem 1fr;
	gap: var( --itg-sp-3 );
	padding-block: 0.55em;
	border-bottom: 1px solid var( --itg-rule );
	font-size: var( --itg-t-s );
}
.spec-row dt { margin: 0; }
.spec-row dd { margin: 0; }

.btn {
	display: inline-block;
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.14em;
	text-transform: uppercase;
	padding: 0.72em 1.3em;
	border: 1px solid var( --itg-ink );
	text-decoration: none;
	transition: background 180ms var( --itg-ease ), color 180ms var( --itg-ease );
}
.btn--solid { background: var( --itg-ink ); color: var( --itg-paper ); }
.btn--solid:hover { background: var( --itg-green ); border-color: var( --itg-green ); }
.btn--quiet:hover { background: var( --itg-ink ); color: var( --itg-paper ); }

.two-plates {
	display: grid;
	grid-template-columns: 1fr 1fr;
	gap: var( --itg-sp-4 );
	margin-top: var( --itg-sp-3 );
}
.two-plates figure { margin: 0; }

.plate-canvas {
	width: 100%;
	aspect-ratio: 3 / 2;
	border: 1px solid var( --itg-rule );
	background: color-mix( in srgb, var( --itg-paper ) 70%, #fff );
}
.plate-caption {
	display: flex;
	justify-content: space-between;
	gap: var( --itg-sp-3 );
	margin-top: var( --itg-sp-2 );
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	color: var( --itg-ink-faint );
}

/* ---- 2. THE DOCUMENT ------------------------------------------------- */

.doc-header {
	border-bottom: 1px solid var( --itg-rule );
	position: sticky;
	top: 0;
	z-index: 20;
	background: color-mix( in srgb, var( --itg-paper ) 94%, transparent );
	backdrop-filter: blur( 6px );
}
.doc-header .inner {
	max-width: 76rem;
	margin: 0 auto;
	padding: var( --itg-sp-3 ) var( --itg-sp-4 );
	display: flex;
	align-items: baseline;
	justify-content: space-between;
	gap: var( --itg-sp-4 );
}
.doc-header .brand { text-decoration: none; display: flex; align-items: baseline; gap: 0.55rem; }
.doc-header .brand .name { font-size: var( --itg-t-l ); }
.doc-header .brand .sub {
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.16em;
	text-transform: uppercase;
	color: var( --itg-ink-faint );
}
.doc-nav ul { list-style: none; display: flex; gap: var( --itg-sp-4 ); margin: 0; padding: 0; }
.doc-nav a {
	text-decoration: none;
	font-family: var( --itg-ff-data );
	font-size: var( --itg-t-xs );
	letter-spacing: 0.13em;
	text-transform: uppercase;
	color: var( --itg-ink-soft );
}
.doc-nav a:hover { color: var( --itg-ink ); }

.wrap { max-width: 76rem; margin: 0 auto; padding: 0 var( --itg-sp-4 ); }
.measure { max-width: 40rem; }

.section { padding-block: var( --itg-sp-7 ); }
.section--tight { padding-block: var( --itg-sp-6 ); }

.crumbs { margin-bottom: var( --itg-sp-4 ); }
.crumbs ul { list-style: none; display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0; padding: 0;
	font-family: var( --itg-ff-data ); font-size: var( --itg-t-xs ); letter-spacing: 0.1em;
	text-transform: uppercase; color: var( --itg-ink-faint ); }
.crumbs li + li::before { content: "/"; margin-right: 0.4rem; color: var( --itg-rule ); }
.crumbs a { text-decoration: none; }
.crumbs a:hover { color: var( --itg-ink ); }

.page-title { font-family: var( --itg-ff-text ); font-weight: 400; font-size: var( --itg-t-3xl );
	line-height: 1.12; margin: 0 0 var( --itg-sp-3 ); text-wrap: balance; }
.lede { font-size: var( --itg-t-l ); color: var( --itg-ink-soft ); max-width: 50ch; }

.prose { max-width: 40rem; }
.prose h2 { font-size: var( --itg-t-xl ); font-weight: 400; margin: var( --itg-sp-5 ) 0 var( --itg-sp-2 ); }
.prose h3 { font-size: var( --itg-t-l ); font-weight: 400; margin: var( --itg-sp-4 ) 0 var( --itg-sp-2 ); }
.prose p { margin: 0 0 var( --itg-sp-3 ); }
.prose blockquote { margin: var( --itg-sp-4 ) 0; padding-left: var( --itg-sp-3 );
	border-left: 2px solid var( --itg-green ); color: var( --itg-ink-soft ); }
.prose img { margin-block: var( --itg-sp-4 ); }

.rows { border-top: 1px solid var( --itg-rule ); }
.row {
	display: grid;
	grid-template-columns: 7rem 1fr auto;
	gap: var( --itg-sp-4 );
	align-items: baseline;
	padding: var( --itg-sp-4 ) 0;
	border-bottom: 1px solid var( --itg-rule );
	text-decoration: none;
	transition: background 160ms var( --itg-ease );
}
.row:hover { background: var( --itg-paper-2 ); }
.row .idx { font-family: var( --itg-ff-data ); font-size: var( --itg-t-xs );
	letter-spacing: 0.1em; color: var( --itg-ink-faint ); }
.row .title { font-size: var( --itg-t-xl ); line-height: 1.16; }
.row .meta { font-family: var( --itg-ff-data ); font-size: var( --itg-t-xs );
	letter-spacing: 0.1em; text-transform: uppercase; color: var( --itg-ink-faint );
	white-space: nowrap; }

/* Commission rows get a thumbnail of the actual piece; the security-features
   register stays plain text — it is read as a specification sheet, not
   browsed as a gallery, so a thumbnail there would be decoration. */
.row--photo { grid-template-columns: 4.5rem 7rem 1fr auto; }
.row-media { width: 4.5rem; height: 3.4rem; overflow: hidden; align-self: center; background: var( --itg-paper-2 ); }
.row-media img { width: 100%; height: 100%; object-fit: cover; display: block; }
@media ( max-width: 640px ) {
	.row--photo { grid-template-columns: 3.4rem 1fr; }
	.row--photo .idx { display: none; }
}

.doc-footer {
	border-top: 1px solid var( --itg-rule );
	margin-top: var( --itg-sp-7 );
	padding-block: var( --itg-sp-6 ) var( --itg-sp-5 );
	background: var( --itg-paper-2 );
}
.doc-footer .cols {
	display: grid;
	grid-template-columns: 1.4fr repeat( 3, 1fr );
	gap: var( --itg-sp-5 );
}
.doc-footer ul { list-style: none; margin: 0; padding: 0; }
.doc-footer li { margin-bottom: 0.45rem; }
.doc-footer a { text-decoration: none; font-size: var( --itg-t-s ); }
.doc-footer a:hover { text-decoration: underline; }
.doc-footer .colophon {
	margin-top: var( --itg-sp-5 );
	padding-top: var( --itg-sp-3 );
	border-top: 1px solid var( --itg-rule );
	display: flex; justify-content: space-between; flex-wrap: wrap; gap: var( --itg-sp-3 );
	font-family: var( --itg-ff-data ); font-size: var( --itg-t-xs ); color: var( --itg-ink-faint );
}

.pagination { margin-top: var( --itg-sp-5 ); font-family: var( --itg-ff-data ); font-size: var( --itg-t-s ); }
.pagination .page-numbers { padding: 0.3em 0.6em; text-decoration: none; }
.pagination .current { background: var( --itg-ink ); color: var( --itg-paper ); }


/* ---- 3. THE HOMEPAGE SECTIONS ---------------------------------------- */

.section-title {
	font-family: var( --itg-ff-text );
	font-weight: 400;
	font-size: var( --itg-t-2xl );
	line-height: 1.14;
	margin: 0 0 var( --itg-sp-3 );
	padding-bottom: var( --itg-sp-2 );
	border-bottom: 1px solid var( --itg-rule );
}

/* Hero: the claim on the left, the facts a buyer scans on the right. */
.hero {
	display: grid;
	grid-template-columns: 1.6fr 1fr;
	gap: var( --itg-sp-6 );
	align-items: start;
}
.hero .page-title { margin-top: var( --itg-sp-3 ); max-width: 18ch; }
.hero-cta {
	display: flex;
	flex-wrap: wrap;
	gap: var( --itg-sp-3 );
	margin-top: var( --itg-sp-4 );
}
.hero-facts {
	margin: 0;
	display: grid;
	grid-template-columns: 1fr 1fr;
	gap: 0;
	border-top: 1px solid var( --itg-rule );
}
.hero-facts > div {
	padding: var( --itg-sp-3 ) 0;
	border-bottom: 1px solid var( --itg-rule );
}
.hero-facts > div:nth-child(odd) { padding-right: var( --itg-sp-3 ); }
.hero-facts dt { margin: 0 0 0.3rem; }
.hero-facts dd { margin: 0; font-size: var( --itg-t-l ); }

/* A full-bleed photograph between the hero and the catalogue — the one place
   on the page that shows the house rather than describes it. Everything
   else stays typographic on purpose; one photo band reads as considered,
   a photo behind every section reads as stock-photo filler. */
.photo-band {
	position: relative;
	height: clamp( 16rem, 34vw, 26rem );
	overflow: hidden;
	margin: 0 0 var( --itg-sp-6 );
}
.photo-band img {
	width: 100%; height: 100%;
	object-fit: cover;
	display: block;
}
.photo-band figcaption {
	position: absolute;
	left: 0; right: 0; bottom: 0;
	padding: var( --itg-sp-4 ) var( --itg-sp-4 ) var( --itg-sp-3 );
	background: linear-gradient( to top, rgba(19,26,23,0.72), rgba(19,26,23,0) );
	color: #f3efe6;
}
.photo-band figcaption .label { color: rgba(243,239,230,0.72); }
.photo-band figcaption p { margin: 0.3rem 0 0; max-width: 46ch; font-family: var( --itg-ff-text ); }

/* A plain, honest card grid. Hairlines rather than boxes, because the whole
   house style is engraved rule work rather than drop shadows. */
.tiles {
	display: grid;
	grid-template-columns: repeat( 3, 1fr );
	gap: var( --itg-sp-5 ) var( --itg-sp-5 );
}
.tile { border-top: 1px solid var( --itg-ink ); padding-top: var( --itg-sp-3 ); }
.tile-media {
	display: block;
	aspect-ratio: 4 / 3;
	overflow: hidden;
	margin-bottom: var( --itg-sp-3 );
	background: var( --itg-paper-2 );
}
.tile-media img { width: 100%; height: 100%; object-fit: cover; display: block; }
.tile h3 {
	font-family: var( --itg-ff-text );
	font-weight: 400;
	font-size: var( --itg-t-l );
	line-height: 1.2;
	margin: var( --itg-sp-2 ) 0 var( --itg-sp-2 );
}
.tile p { margin: 0; font-size: var( --itg-t-s ); color: var( --itg-ink-soft ); }

/* Tiles without a photo (the process steps) keep the original plain rule —
   .tile-media is simply absent, nothing to adapt. */

.cta-band {
	position: relative;
	display: flex;
	flex-wrap: wrap;
	gap: var( --itg-sp-4 );
	align-items: center;
	justify-content: space-between;
	padding: var( --itg-sp-5 );
	background: var( --itg-ink );
	border-top: 2px solid var( --itg-ink );
	overflow: hidden;
	isolation: isolate;
}
.cta-band::before {
	content: "";
	position: absolute; inset: 0;
	background-image: var( --itg-cta-photo );
	background-size: cover;
	background-position: center;
	opacity: 0.34;
	z-index: -2;
}
.cta-band::after {
	content: "";
	position: absolute; inset: 0;
	background: linear-gradient( 100deg, rgba(19,26,23,0.92) 0%, rgba(19,26,23,0.72) 60%, rgba(19,26,23,0.5) 100% );
	z-index: -1;
}
.cta-band .cta-title,
.cta-band p { color: #f3efe6; }
.cta-band .muted { color: rgba(243,239,230,0.78) !important; }
.cta-band .btn--quiet { color: #f3efe6; border-color: rgba(243,239,230,0.5); }
.cta-title {
	margin: 0 0 var( --itg-sp-2 );
	font-family: var( --itg-ff-text );
	font-weight: 400;
	font-size: var( --itg-t-2xl );
	line-height: 1.16;
}
.cta-band .btn + .btn { margin-left: var( --itg-sp-2 ); }

@media ( max-width: 900px ) {
	.hero { grid-template-columns: 1fr; gap: var( --itg-sp-5 ); }
	.tiles { grid-template-columns: 1fr 1fr; }
}
@media ( max-width: 640px ) {
	.tiles { grid-template-columns: 1fr; }
	.hero-facts { grid-template-columns: 1fr; }
	.cta-band { padding: var( --itg-sp-4 ); }
	.cta-band .btn + .btn { margin-left: 0; margin-top: var( --itg-sp-2 ); }
	.photo-band { height: 14rem; }
}

/* ---- Forms ----------------------------------------------------------- */

.field { display: block; margin-bottom: var( --itg-sp-3 ); }
.field span { display: block; margin-bottom: 0.3rem; }
.field input, .field textarea, .field select {
	width: 100%;
	padding: 0.65em 0.75em;
	background: color-mix( in srgb, var( --itg-paper ) 60%, #fff );
	border: 1px solid var( --itg-rule );
	border-radius: 0;
	font-family: var( --itg-ff-ui );
	font-size: var( --itg-t-s );
}
.field input:focus, .field textarea:focus, .field select:focus { border-color: var( --itg-green ); outline: none; }
.field--hp { position: absolute; left: -9999px; }
.form-note { font-family: var( --itg-ff-data ); font-size: var( --itg-t-xs ); margin-top: var( --itg-sp-2 ); }

/* ---- Responsive ------------------------------------------------------ */

@media ( max-width: 900px ) {
	.doc-footer .cols { grid-template-columns: 1fr 1fr; }
	.region { width: 24rem; }
	.region--wide { width: 26rem; }
	

	/* A rail down the left edge cannot work on a narrow screen: there is no
	   margin to put it in, so it lands straight across the content. Below
	   900px it becomes a bar along the bottom instead, which also frees the
	   whole width for the plane. */
	.plane.is-plane .plane-rail {
		left: 0; right: 0; top: auto; bottom: 0;
		background: color-mix( in srgb, var( --itg-paper-2 ) 96%, transparent );
		transform: none;
		flex-direction: row;
		justify-content: space-between;
		align-items: center;
		gap: var( --itg-sp-2 );
		padding: var( --itg-sp-2 ) var( --itg-sp-3 );
		border-top: 1px solid var( --itg-rule );
	}
	.plane-rail::before { display: none; }
	.plane-rail button { padding: 0.35rem 0.2rem; }
	/* The tick marks belong to the vertical rule; without it they are noise. */
	.plane-rail button::before { display: none; }
	.plane-rail button[aria-current="true"] { text-decoration: underline; text-underline-offset: 0.35em; }
	/* Five labels will not fit across a phone. The figures alone are the
	   navigation; the labels are a desktop luxury. */
	.plane-rail .rail-label { display: none; }
	/* The bar is its own affordance, so the written hint is redundant. */
	.plane-hint { display: none; }
	.doc-frame { padding: var( --itg-sp-4 ) var( --itg-sp-3 ); }
	.feature-panel { padding: var( --itg-sp-3 ); }
}

@media ( max-width: 640px ) {
	:root { --itg-t-4xl: 2.2rem; --itg-t-3xl: 1.85rem; }
	.doc-header .inner { flex-direction: column; align-items: flex-start; gap: var( --itg-sp-2 ); }
	.doc-nav ul { flex-wrap: wrap; gap: var( --itg-sp-3 ); }
	.doc-footer .cols { grid-template-columns: 1fr; }
	.row { grid-template-columns: 1fr; gap: var( --itg-sp-2 ); }
	.region { width: 18rem; }
	.region--wide { width: 19rem; }
	
}

/* ---- Reduced motion --------------------------------------------------- */

@media ( prefers-reduced-motion: reduce ) {
	*, *::before, *::after {
		animation-duration: 0.001ms !important;
		transition-duration: 0.001ms !important;
	}
}