design: rework for a better DA and light/dark mode

frontend/tailwind.config.ts

@@ -5,6 +5,9 @@ export default {
   content: ['./index.html', './src/**/*.{ts,tsx}'],
   theme: {
     extend: {
+      fontFamily: {
+        serif: ['Playfair Display', 'Georgia', 'serif'],
+      },
       colors: {
         border: 'hsl(var(--border))',
         input: 'hsl(var(--input))',
@@ -17,9 +20,9 @@ export default {
         muted: { DEFAULT: 'hsl(var(--muted))', foreground: 'hsl(var(--muted-foreground))' },
         accent: { DEFAULT: 'hsl(var(--accent))', foreground: 'hsl(var(--accent-foreground))' },
         card: { DEFAULT: 'hsl(var(--card))', foreground: 'hsl(var(--card-foreground))' },
-        bullish: '#22c55e',
-        bearish: '#ef4444',
-        neutral: '#94a3b8',
+        bullish: '#15803d',
+        bearish: '#b91c1c',
+        neutral: '#78716c',
       },
       borderRadius: {
         lg: 'var(--radius)',