Fix dark mode styling for About page (modelcontextprotocol#1438)

* Fix dark mode styling for About page

- Added comprehensive dark mode styles for all landing page elements
- Fixed background colors, text colors, and borders for dark mode
- Added filter to invert MCP logo in dark mode for visibility
- Ensured consistent dark mode experience across the About page

Fixes modelcontextprotocol#1431

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

* Switch to use light-dark, more targeted changes

* Final tweaks based on feedback

---------

Co-authored-by: Claude <[email protected]>

Author: pja-ant

docs/style.css

@@ -225,8 +225,7 @@ body:has(#schema-reference) {
     margin-top: 4rem;
   }
 
-  background: #ffffff;
-  color: #111827;
+  color: light-dark(#111827, #e5e7eb);
   --highlight-color: #6366f1;
 }
 
@@ -356,7 +355,7 @@ body:has(#schema-reference) {
   font-weight: 700;
   margin-bottom: 1.5rem;
   text-align: center;
-  color: #111827;
+  color: light-dark(#111827, #e5e7eb);
 }
 
 /* Intro video section */
@@ -377,7 +376,7 @@ body:has(#schema-reference) {
       font-size: 2.5rem;
       font-weight: 700;
       line-height: 1.2;
-      color: #111827;
+      color: light-dark(#111827, #e5e7eb);
     }
 
     .intro-description {
@@ -579,8 +578,7 @@ body:has(#schema-reference) {
     border-radius: 9999px;
 
     border: 6px solid var(--highlight-color);
-    background: #111827;
-    color: white;
+    color: white
 
     font-size: 1.5rem;
     font-weight: 700;
@@ -593,6 +591,10 @@ body:has(#schema-reference) {
   }
 }
 
+.dark .intro-logo img {
+  filter: invert(1);
+}
+
 @media (max-width: 768px) {
   .features-grid {
     grid-template-columns: 1fr;