chore: simplify globals.css

Remove duplicate body rules and unused CSS custom properties.
Consolidate to a single body rule with gray-950 background and light default text.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: JoeMatt

src/app/globals.css

@@ -1,30 +1,12 @@
 @import "tailwindcss";
 
-:root {
-  --background: #ffffff;
-  --foreground: #171717;
-}
-
 @theme inline {
-  --color-background: var(--background);
-  --color-foreground: var(--foreground);
   --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
   --font-mono: 'SF Mono', Consolas, 'Liberation Mono', Menlo, monospace;
 }
 
-@media (prefers-color-scheme: dark) {
-  :root {
-    --background: #0a0a0a;
-    --foreground: #ededed;
-  }
-}
-
 body {
-  background: var(--background);
-  color: var(--foreground);
+  background-color: #030712; /* gray-950 */
+  color: #ededed;
   font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
 }
-
-body {
-  background-color: #030712; /* gray-950 — matches page backgrounds */
-}