Phase 1: Homepage seamless design - add gradient transitions

- Added gradient transitions between sections in global.css
- Portfolio section now has gradient-top (dark to white fade)
- Blog section now has gradient-bottom (white fade from dark)
- Reduced portfolio overlay opacity from 0.85 to 0.65
- Added border to blog cards for white-on-white visibility
- Blog cards now have primary color accent on hover

package.json

@@ -12,10 +12,11 @@
     "astro": "astro"
   },
   "dependencies": {
-    "@astrojs/node": "^10.0.6",
-    "@astrojs/react": "^5.0.4",
+    "@astrojs/mdx": "^5.0.6",
+    "@astrojs/node": "^10.1.1",
+    "@astrojs/react": "^5.0.5",
     "astro": "^6.2.2",
-    "emdash": "^0.9.0",
+    "emdash": "^0.12.0",
     "react": "^19.2.5",
     "react-dom": "^19.2.5"
   }