feat(ui): add warm newspaper background texture and adjust base color

web/src/index.css

@@ -2,7 +2,7 @@
 @import "tailwindcss";
 
 @theme {
-  --color-carbon: #FAFAF9;
+  --color-carbon: #F0F0EB;
   --color-carbon-light: #FFFFFF;
   --color-carbon-dark: #E7E5E4;
   --color-nature: #166534;
@@ -33,7 +33,10 @@
     @apply bg-carbon text-paper-white font-sans antialiased selection:bg-nature/20;
     margin: 0;
     min-height: 100vh;
-    border-top: 4px solid var(--color-nature); /* Editorial Touch */
+    border-top: 4px solid var(--color-nature);
+    /* Editorial Touch */
+    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.04'/%3E%3C/svg%3E");
+    background-blend-mode: multiply;
   }
 
   h1,