diff --git a/tests/unit/vyndrParityQA.test.js b/tests/unit/vyndrParityQA.test.js
index 33574e1..4a2e25e 100644
--- a/tests/unit/vyndrParityQA.test.js
+++ b/tests/unit/vyndrParityQA.test.js
@@ -265,3 +265,19 @@ describe('P0-4 — mobile app bar is one line (ticker + heartbeat hidden)', () =
     expect(css).toMatch(/\.slate-sticky-head\s*\{\s*top:\s*60px/);
   });
 });
+
+// ── P1-5 lock — 390px containment (strengthened: content, not just doc scroll) ─
+describe('P1-5 — dense rows CONTAIN at 390px (not just html overflow-x:hidden)', () => {
+  const css = read('app/globals.css');
+  it('consensus rows stack at <430px so they never bleed off the right edge', () => {
+    expect(css).toMatch(/@media\s*\(max-width:\s*430px\)\s*\{[^]*?\.breadth-row\s*\{[^}]*flex-direction:\s*column/);
+    expect(css).toMatch(/\.breadth-row\s*>\s*span\s*\{[^}]*overflow-wrap:\s*anywhere/);
+    expect(read('components/vyndr/MarketBreadth.tsx')).toMatch(/breadth-row/);
+  });
+  it('the starting-pitcher line wraps its name/ERA inside the card (no truncation)', () => {
+    const gc = read('components/vyndr/GameCard.tsx');
+    // the inner pitcher spans allow wrap + shrink so "2.64 ERA" never gets cut
+    expect(gc).toMatch(/g\.pitchers\.away\.era/);
+    expect((gc.match(/flexWrap: 'wrap', minWidth: 0/g) || []).length).toBeGreaterThanOrEqual(2);
+  });
+});
diff --git a/web/src/app/globals.css b/web/src/app/globals.css
index 160661e..c507a3e 100644
--- a/web/src/app/globals.css
+++ b/web/src/app/globals.css
@@ -1372,6 +1372,20 @@ html[data-font="readable"] .wm::after { opacity: 0.45 !important; }
 }
 
 
+
+/* P1-5 — 390px CONTAINMENT: dense data rows must WRAP/STACK inside their card,
+   never bleed off the right edge (the M4 no-overflow lock only hid the document
+   scroll; content still clipped). */
+@media (max-width: 430px) {
+  /* CONSENSUS VS MODEL rows stack — player / consensus / model each own line. */
+  .breadth-row { flex-direction: column; align-items: flex-start; gap: 3px; }
+  .breadth-row > span { min-width: 0 !important; max-width: 100%; overflow-wrap: anywhere; }
+}
+@media (max-width: 767px) {
+  /* opt-in scroll-within-card for wide tables (pitcher lines / pill rows). */
+  .mobile-scroll-x { overflow-x: auto; -webkit-overflow-scrolling: touch; max-width: 100%; }
+}
+
 /* P0-4 — MOBILE APP BAR: collapse the 3-row header (nav + ticker + heartbeat)
    to ONE line <768px. The ticker row + the whole heartbeat bar are hidden; the
    nav's right cluster shows the app-bar clock (nav-mobile-clock). main's top
diff --git a/web/src/components/vyndr/GameCard.tsx b/web/src/components/vyndr/GameCard.tsx
index 2c8d4b8..698c7e7 100644
--- a/web/src/components/vyndr/GameCard.tsx
+++ b/web/src/components/vyndr/GameCard.tsx
@@ -263,12 +263,12 @@ export default function GameCard({ game: g, onAddParlay, onOpen, preferredBooks
       {g.pitchers && (
         <div className="mono" style={{ padding: '0 16px 11px', fontSize: 11, color: 'var(--text-1)', display: 'flex', alignItems: 'center', gap: 8, flexWrap: 'wrap' }}>
           <span style={{ color: 'var(--text-2)', letterSpacing: '0.04em' }}>STARTING</span>
-          <span style={{ display: 'inline-flex', alignItems: 'center', gap: 6, color: '#C8CCD6' }}>
+          <span style={{ display: 'inline-flex', alignItems: 'center', gap: 6, color: '#C8CCD6', flexWrap: 'wrap', minWidth: 0 }}>
             {g.pitchers.away.name} <span style={{ color: 'var(--text-1)' }}>{g.pitchers.away.era} ERA</span>
             {g.pitchers.away.archetype && <ArchetypeBadge archetype={g.pitchers.away.archetype} size="sm" />}
           </span>
           <span style={{ color: 'var(--text-2)' }}>vs</span>
-          <span style={{ display: 'inline-flex', alignItems: 'center', gap: 6, color: '#C8CCD6' }}>
+          <span style={{ display: 'inline-flex', alignItems: 'center', gap: 6, color: '#C8CCD6', flexWrap: 'wrap', minWidth: 0 }}>
             {g.pitchers.home.name} <span style={{ color: 'var(--text-1)' }}>{g.pitchers.home.era} ERA</span>
             {g.pitchers.home.archetype && <ArchetypeBadge archetype={g.pitchers.home.archetype} size="sm" />}
           </span>
diff --git a/web/src/components/vyndr/MarketBreadth.tsx b/web/src/components/vyndr/MarketBreadth.tsx
index 598b47f..0240789 100644
--- a/web/src/components/vyndr/MarketBreadth.tsx
+++ b/web/src/components/vyndr/MarketBreadth.tsx
@@ -87,8 +87,8 @@ export default function MarketBreadth({
           return (
             <div
               key={`${r.player}-${r.stat}-${i}`}
-              className="mono"
-              style={{ display: 'flex', alignItems: 'baseline', gap: 10, fontSize: 12, flexWrap: 'wrap', fontVariantNumeric: 'tabular-nums' }}
+              className="mono breadth-row"
+              style={{ display: 'flex', alignItems: 'baseline', gap: 10, fontSize: 12, flexWrap: 'wrap', fontVariantNumeric: 'tabular-nums', minWidth: 0 }}
             >
               {r.player && <span style={{ color: 'var(--text-0)', fontWeight: 700, minWidth: 96 }}>{r.player}</span>}
               <span style={{ color: 'var(--text-1)' }}>