feat(compare): fill the sticky bar's label rail with a comparison caption

'COMPARING / 3 primary schools' — 0.72rem uppercase eyebrow over a
0.95rem semibold count, sized to sit alongside the 0.92rem chip names
without dominating. Desktop only; mobile pills unchanged.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0146VHeLAWjDVE2B5uU67jCB

e2e/tests/journeys.spec.ts

@@ -204,6 +204,8 @@ test('comparing two schools shows the parent-first sections side by side', async
     .locator('[aria-label="Schools in this comparison"]')
     .evaluate((el) => getComputedStyle(el).gridTemplateColumns);
   expect(barTemplate).toMatch(/^200px /);
+  // ...and its label rail carries the comparison caption.
+  await expect(page.getByText(/^\d+ (primary|secondary) schools?$/)).toBeVisible();
 
   // Ofsted linkout goes to the school's provider page, never a report deep-link
   const ofstedLink = page.getByRole('link', { name: /Ofsted page/i }).first();

nextjs-app/__tests__/components/ComparisonView.phase.test.tsx

@@ -72,5 +72,7 @@ test('an all-secondary comparison renders the sections, not an empty primary tab
   });
   expect(screen.getAllByText('Gamma High').length).toBeGreaterThan(0);
   expect(screen.queryByText(/No primary schools in your comparison/)).toBeNull();
+  // The sticky bar's rail caption reflects the active phase and count.
+  expect(screen.getByText('2 secondary schools')).toBeInTheDocument();
   expect(fetchComparison).not.toHaveBeenCalled();
 });

nextjs-app/components/ComparisonView.module.css

@@ -148,10 +148,16 @@
   text-overflow: ellipsis;
 }
 
+/* Caption filling the label rail on desktop ("Comparing / 3 primary
+   schools"). Hidden on mobile, where the bar is a row of compact pills. */
+.barCaption {
+  display: none;
+}
+
 /* Desktop (matches the sections' 761px breakpoint): the bar adopts the same
    grid template as compareSections' .grid — a 200px row-label rail plus one
    column per school — so each chip sits exactly over the column it labels.
-   The first chip starts after the empty label rail. */
+   The caption occupies the rail; chips flow into the school columns. */
 @media (min-width: 761px) {
   .schoolBar {
     display: grid;
@@ -164,8 +170,29 @@
     min-width: 0;
   }
 
-  .schoolChip:first-child {
-    grid-column: 2;
+  .barCaption {
+    grid-column: 1;
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    gap: 0.1rem;
+    padding-right: 0.5rem;
+    min-width: 0;
+  }
+
+  .barCaptionEyebrow {
+    font-size: 0.72rem;
+    font-weight: 600;
+    letter-spacing: 0.06em;
+    text-transform: uppercase;
+    color: var(--text-muted, #6d685f);
+  }
+
+  .barCaptionCount {
+    font-size: 0.95rem;
+    font-weight: 600;
+    line-height: 1.3;
+    color: var(--text-primary, #1a1612);
   }
 }
 

nextjs-app/components/ComparisonView.tsx

@@ -350,6 +350,14 @@ export function ComparisonView({
             style={{ '--school-count': activeSchools.length } as CSSProperties}
             aria-label="Schools in this comparison"
           >
+            {/* Fills the 200px label rail on desktop (hidden on mobile). */}
+            <div className={styles.barCaption}>
+              <span className={styles.barCaptionEyebrow}>Comparing</span>
+              <span className={styles.barCaptionCount}>
+                {activeSchools.length} {comparePhase} school
+                {activeSchools.length === 1 ? '' : 's'}
+              </span>
+            </div>
             {activeSchools.map((school, index) => (
               <div
                 key={school.urn}