style: Update color theme in styles.css file

frontend/src/styles.css

@@ -1,5 +1,22 @@
 @import 'tailwindcss';
-/* Color theme moved to tailwind.config.js */
+
+@theme {
+  --color-deep-blue: #0a1219;
+  --color-deep-blue-light: #121e27;
+  --color-deep-blue-contrast: #1a2835;
+
+  --color-emerald: #10b981;
+  --color-emerald-dark: #059669;
+  --color-emerald-light: #34d399;
+
+  --color-text-primary: #ffffff;
+  --color-text-secondary: #94a3b8;
+  --color-text-tertiary: #64748b;
+
+  --color-accent-yellow: #fbbf24;
+  --color-accent-red: #ef4444;
+  --color-accent-purple: #8b5cf6;
+}
 
 body {
   @apply bg-deep-blue text-text-primary h-full;