fix(ui): implement comprehensive CSS layout audit remediations (Antigravity)

src/app/globals.css

@@ -123,6 +123,10 @@
 
 /* Theme tokens */
 :root {
+  /* Layout constraints */
+  --content-max-width: 1440px;
+  --rail-width: 480px;
+
   /* Clinical White: true-neutral graphite-to-ash ramp (de-blued). */
   --neutral-0: #ffffff;
   --neutral-50: #f7f8fa;
@@ -1809,7 +1813,7 @@ summary::-webkit-details-marker {
      beside the main column. */
   .document-viewer-composer.floating-composer-edge {
     left: max(2rem, var(--safe-area-left));
-    right: calc(max(0px, (100vw - 1440px) / 2) + 480px + 3.5rem + var(--safe-area-right));
+    right: calc(max(0px, (100vw - var(--content-max-width)) / 2) + var(--rail-width) + 3.5rem + var(--safe-area-right));
   }
 }
 
@@ -2948,7 +2952,10 @@ html.theme-transitioning *:after {
   }
 }
 
-/* Windows High Contrast / Forced Colors Compatibility (Improvement 2.3) */
+/* Windows High Contrast / Forced Colors Compatibility (Improvement 2.3).
+   Token remap only — glass-header Canvas fills live in the earlier
+   forced-colors block; do not blanket-reset [aria-selected="true"] or
+   invent unused .surface-raised selectors with !important. */
 @media (forced-colors: active) {
   :root,
   .dark {

src/components/AccessibleTable.tsx

@@ -98,7 +98,7 @@ function AccessibleTableMarkup({
   return (
     <div
       className={cn(
-        "overflow-hidden rounded-lg border border-[color:var(--border)] bg-[color:var(--surface)]",
+        "@container overflow-hidden rounded-lg border border-[color:var(--border)] bg-[color:var(--surface)]",
         expanded && "max-h-[calc(100dvh-8.5rem)] flex flex-col rounded-none border-0 sm:rounded-lg sm:border",
       )}
     >

src/components/DocumentManagementActions.tsx

@@ -254,7 +254,7 @@ export function DocumentManagementActions({
                 disabled={pending}
               />
             </label>
-            <p className={cn("truncate text-xs", textMuted)}>Original file: {document.file_name}</p>
+            <p className={cn("truncate text-xs min-w-0", textMuted)}>Original file: {document.file_name}</p>
             <div className="flex flex-wrap justify-end gap-2">
               <button type="button" className={floatingControl} onClick={closeDialog} disabled={pending}>
                 Cancel

src/components/clinical-dashboard/document-search-results.tsx

@@ -631,6 +631,7 @@ function SearchRecordResults({
               data-testid={`${copy.testIdPrefix}-result-${service.slug}`}
               className={cn(
                 sourceCard,
+                "content-auto",
                 "grid gap-3 p-3 shadow-[var(--shadow-tight)] transition hover:border-[color:var(--clinical-accent-border)] sm:p-4",
                 index === 0 && "ring-1 ring-[color:var(--clinical-accent)]/15",
               )}
@@ -1011,6 +1012,7 @@ function DocumentSearchResultsPanelImpl({
                     key={document.document_id}
                     className={cn(
                       sourceCard,
+                      "content-auto",
                       "relative overflow-visible p-0 shadow-[var(--shadow-tight)] transition hover:border-[color:var(--clinical-accent-border)] hover:shadow-[var(--shadow-hover)]",
                       selected &&
                         "border-[color:var(--clinical-accent-border)] ring-1 ring-[color:var(--clinical-accent)]/20",

src/components/settings-search-mockups/settings-search-mockup-page.tsx

@@ -647,7 +647,7 @@ function BoardShell({ children, concept }: { children: ReactNode; concept: Conce
       <main
         className={cn(
           appBackdrop,
-          "fixed inset-0 z-[2147483647] overflow-auto px-4 py-7 text-[color:var(--text-heading)] sm:px-8",
+          "fixed inset-0 z-[100] overflow-auto px-4 py-7 text-[color:var(--text-heading)] sm:px-8",
         )}
       >
         <div className="mx-auto max-w-[1320px]">