fix(about): differentiate medium-card eyebrows; co-locate orphaned media query

Studio/Live/DJ Set eyebrows mirror Home's established vocabulary.
Orphaned @media (max-width: 960px) for .section-dark-standfirst
merged into the sibling dark-section block.

DeepDrftPublic.Client/Pages/About.razor.css

@@ -332,6 +332,7 @@
     .features-grid { grid-template-columns: repeat(2, 1fr); }
     .feature-card { border-right: none; border-bottom: 1px solid rgba(250, 250, 248, 0.08); }
     .feature-card:last-child { border-bottom: none; }
+    .section-dark-standfirst { font-size: 0.88rem; }
 }
 
 @media (max-width: 599px) {
@@ -635,7 +636,3 @@
     color: var(--deepdrft-navy);
     opacity: 0.7;
 }
-
-@media (max-width: 960px) {
-    .section-dark-standfirst { font-size: 0.88rem; }
-}