diff --git a/cli/engine/engines/regex/detect-text.mjs b/cli/engine/engines/regex/detect-text.mjs
index ff4db4228..02d63eac3 100644
--- a/cli/engine/engines/regex/detect-text.mjs
+++ b/cli/engine/engines/regex/detect-text.mjs
@@ -425,11 +425,15 @@ function scanInsetStripeCss(rawContent, filePath, lineOffset = 0) {
       // an unchanged layer had no inset keyword and is not our shape.
       const body = layer.replace(/(^|\s)inset(?=\s|$)/i, '$1').trim();
       if (body === layer) continue;
-      const shadow = body.match(/^(-?\d*\.?\d+)(px)?\s+(-?\d*\.?\d+)(px)?\s+(-?\d*\.?\d+)(px)?(?:\s+(-?\d*\.?\d+)(px)?)?\s+(.+)$/i);
+      // box-shadow takes <length>{2,4}: only the two offsets are required, so
+      // `inset 4px 0 red` is valid and paints the same stripe as
+      // `inset 4px 0 0 red`. Demanding a third length missed the short form.
+      const shadow = body.match(/^(-?\d*\.?\d+)(px)?\s+(-?\d*\.?\d+)(px)?(?:\s+(-?\d*\.?\d+)(px)?)?(?:\s+(-?\d*\.?\d+)(px)?)?\s+(.+)$/i);
       if (!shadow) continue;
       const x = Number(shadow[1]);
       const y = Number(shadow[3]);
-      const blur = Number(shadow[5]);
+      // Omitted blur and spread default to 0, which is exactly the stripe shape.
+      const blur = shadow[5] == null ? 0 : Number(shadow[5]);
       const spread = shadow[7] == null ? 0 : Number(shadow[7]);
       if ((x !== 0 && !shadow[2]) || (y !== 0 && !shadow[4]) || blur !== 0 || spread !== 0) continue;
       const ax = Math.abs(x);
diff --git a/tests/detect-antipatterns-fixtures.test.mjs b/tests/detect-antipatterns-fixtures.test.mjs
index a6d9f9892..8b268d5df 100644
--- a/tests/detect-antipatterns-fixtures.test.mjs
+++ b/tests/detect-antipatterns-fixtures.test.mjs
@@ -33,6 +33,9 @@ describe('detectText - Astro structural CSS fixtures', () => {
     'Trailing Inset Edge',
     'Trailing Inset Token Edge',
     'Inset Named Token Edge',
+    // Only the two offsets are required; blur/spread default to 0.
+    'Two Length Edge',
+    'Two Length Trailing Inset Edge',
   ];
   const SHOULD_PASS = [
     'Neutral Shadow Token',
@@ -56,6 +59,9 @@ describe('detectText - Astro structural CSS fixtures', () => {
     'Commented Out Edge',
     // Trailing `inset` still respects the neutral-color exemption.
     'Trailing Inset Neutral Edge',
+    // The short form still respects the neutral and blur exclusions.
+    'Two Length Neutral Edge',
+    'Two Length Blurred Edge',
   ];
 
   it('Astro style blocks flag unresolved chromatic inset stripes only', () => {
diff --git a/tests/fixtures/antipatterns/astro-inset-shadow-stripe.astro b/tests/fixtures/antipatterns/astro-inset-shadow-stripe.astro
index a93c6e396..d836e66d4 100644
--- a/tests/fixtures/antipatterns/astro-inset-shadow-stripe.astro
+++ b/tests/fixtures/antipatterns/astro-inset-shadow-stripe.astro
@@ -17,6 +17,8 @@ const title = 'Astro inset shadow stripe regression';
     <article data-case="Trailing Inset Edge"><h3>Trailing Inset Edge</h3></article>
     <article data-case="Trailing Inset Token Edge"><h3>Trailing Inset Token Edge</h3></article>
     <article data-case="Inset Named Token Edge"><h3>Inset Named Token Edge</h3></article>
+    <article data-case="Two Length Edge"><h3>Two Length Edge</h3></article>
+    <article data-case="Two Length Trailing Inset Edge"><h3>Two Length Trailing Inset Edge</h3></article>
   </section>
   <section aria-labelledby="should-pass">
     <h2 id="should-pass">Should pass</h2>
@@ -35,6 +37,8 @@ const title = 'Astro inset shadow stripe regression';
     <article data-case="Shorthand Neutral Hex Edge"><h3>Shorthand Neutral Hex Edge</h3></article>
     <article data-case="Commented Out Edge"><h3>Commented Out Edge</h3></article>
     <article data-case="Trailing Inset Neutral Edge"><h3>Trailing Inset Neutral Edge</h3></article>
+    <article data-case="Two Length Neutral Edge"><h3>Two Length Neutral Edge</h3></article>
+    <article data-case="Two Length Blurred Edge"><h3>Two Length Blurred Edge</h3></article>
   </section>
 </main>
 
@@ -71,6 +75,13 @@ const title = 'Astro inset shadow stripe regression';
   [data-case="Inset Named Token Edge"] { box-shadow: inset 4px 0 0 var(--inset-accent); }
   [data-case="Trailing Inset Neutral Edge"] { box-shadow: 4px 0 0 #000 inset; }
 
+  /* box-shadow takes <length>{2,4}: blur and spread are optional and default to
+     0, so these paint the same stripe as the four-length forms above. */
+  [data-case="Two Length Edge"] { box-shadow: inset 4px 0 var(--brand-accent); }
+  [data-case="Two Length Trailing Inset Edge"] { box-shadow: 0 5px #6366f1 inset; }
+  [data-case="Two Length Neutral Edge"] { box-shadow: inset 4px 0 #000; }
+  [data-case="Two Length Blurred Edge"] { box-shadow: inset 4px 0 5px var(--brand-accent); }
+
   /* Commented-out rules are not live CSS.
   [data-case="Commented Out Edge"] { box-shadow: inset 4px 0 0 var(--brand-accent); }
   */