diff --git a/src/components/PageContent/PageContent.astro b/src/components/PageContent/PageContent.astro
index 07be96ec6e..0753458490 100644
--- a/src/components/PageContent/PageContent.astro
+++ b/src/components/PageContent/PageContent.astro
@@ -36,6 +36,7 @@ const agentSetupHref =
 		? undefined
 		: await getPageHref('documentation_agent_setup', lang as Lang);
 const t = useTranslations(Astro);
+const COLUMN = 'layout-column-content layout-boundary-inline';
 const headerLabels = {
 	lastUpdated: t('pageHeader.lastUpdated'),
 	copy: t('pageHeader.copy'),
@@ -79,7 +80,7 @@ const headerLabels = {
 				/>
 			)
 		}
-		<section class="layout-boundary-inline">
+		<section class={COLUMN}>
 			<ReadableContent client:load>
 				{
 					isFallback && (
@@ -100,7 +101,7 @@ const headerLabels = {
 					next={next && { title: next.text, href: next.link }}
 					previousLabel={t('articleNav.prevPage')}
 					nextLabel={t('articleNav.nextPage')}
-					class="px-container pt-12"
+					class={`${COLUMN} pt-12`}
 				/>
 			)
 		}
@@ -108,29 +109,7 @@ const headerLabels = {
 </div>
 
 <style is:global>
-	/*
-	 * THE BANNER IS FULL BLEED, ITS CONTENT IS CONTAINED. The masthead keeps the
-	 * whole column's width — its `border-b` is the page's horizon and has to reach
-	 * both edges — so the alignment is paid for in padding rather than by wrapping
-	 * it in `px-container`, which would pull the rule in with the words.
-	 *
-	 * The padding is `px-container`'s own math: the centering margin a 4xl column
-	 * would have taken, `(100% - 4xl) / 2`, and never negative — `min(100%, …)`
-	 * folds it to zero while the column is narrower than the measure — plus that
-	 * utility's gutter at the same breakpoint. Change one and change the other, or
-	 * the title stops sitting over the first paragraph.
-	 *
-	 * Unlayered on purpose: a plain declaration outranks Tailwind's layered
-	 * utilities, so this needs no `!important` — and, because Tailwind is imported
-	 * in `important` mode here, an `!important` override would have lost anyway.
-	 */
 	.doc-page-banner {
-		padding-inline: calc((100% - min(100%, var(--container-4xl))) / 2 + 1rem);
-	}
-
-	@media (min-width: 768px) {
-		.doc-page-banner {
-			padding-inline: calc((100% - min(100%, var(--container-4xl))) / 2 + 2rem);
-		}
+		padding-inline: max(var(--layout-boundary-inline), (100% - var(--layout-measure-content)) / 2);
 	}
 </style>
diff --git a/src/layouts/DocsDirectoryLayout.astro b/src/layouts/DocsDirectoryLayout.astro
index 7cceb1c4c0..8604ba38ee 100644
--- a/src/layouts/DocsDirectoryLayout.astro
+++ b/src/layouts/DocsDirectoryLayout.astro
@@ -3,7 +3,7 @@
 // Three pieces of the reading shell are wrong for one, and each is dropped here: the docs
 // rail (`primarySidebar={false}` — the page's own filter column is the navigation), the
 // "On this page" outline (no `secondary-sidebar` slot, so no third track is reserved), and
-// `PageContent`'s prose measure (4xl, the one width a card grid must not take). The docs
+// `PageContent`'s prose measure (3xl, the one width a card grid must not take). The docs
 // container stays, so the shell holds under the first link out. The closing prev/next pair
 // does not: it walks a reading SEQUENCE, and a catalog is the thing you pick from, not a
 // page in one — "Next page" under 351 cards names a neighbour nobody was reading toward.
diff --git a/src/styles/main.css b/src/styles/main.css
index 9f80ee805d..f35b613aa4 100644
--- a/src/styles/main.css
+++ b/src/styles/main.css
@@ -19,19 +19,6 @@
 	}
 }
 
-@utility px-container {
-	max-width: var(--container-4xl);
-	margin-left: auto;
-	margin-right: auto;
-	padding-left: 1rem;
-	padding-right: 1rem;
-
-	@media (min-width: 768px) {
-		padding-left: 2rem;
-		padding-right: 2rem;
-	}
-}
-
 /* THE DOCS HOME OPENS ITS SECTIONS ONE RUNG WIDER THAN THE PROSE LADDER. DocProse pins
    its section step to a flat 56, a rung fitted to FLOWING COPY; every section here is a
    heading, one sentence and a bordered grid, so at 56 the grids read as one stack with