fix: center Two Ways to Evaluate grid for 2 columns

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 2 people

static/css/style.css

@@ -626,8 +626,10 @@ section {
 
 .interfaces-grid {
   display: grid;
-  grid-template-columns: repeat(3, 1fr);
+  grid-template-columns: repeat(2, 1fr);
   gap: 1.5rem;
+  max-width: 700px;
+  margin: 0 auto;
 }
 
 @media (max-width: 768px) {