fix: Restore CSS matching old site design

- Tailwind v4 syntax (@layer base/components)
- Restored all component classes (.btn-primary, .card, etc.)
- Industrial theme colors preserved
- Typography matching old site

src/styles/globals.css

@@ -1,9 +1,70 @@
 @import "tailwindcss";
 
-/* Custom industrial theme colors */
+/* Base styles */
+@layer base {
+  html {
+    scroll-behavior: smooth;
+  }
+  
+  body {
+    @apply bg-white text-secondary-900 antialiased;
+  }
+  
+  h1, h2, h3, h4, h5, h6 {
+    @apply font-bold tracking-tight;
+  }
+}
+
+/* Component classes - matching old site */
+@layer components {
+  .btn-primary {
+    @apply inline-flex items-center justify-center px-6 py-3 bg-primary-600 text-white font-semibold rounded-lg
+           hover:bg-primary-700 transition-all duration-200 shadow-bold hover:shadow-industrial
+           active:translate-y-0.5;
+  }
+  
+  .btn-secondary {
+    @apply inline-flex items-center justify-center px-6 py-3 bg-secondary-800 text-white font-semibold rounded-lg
+           hover:bg-secondary-900 transition-all duration-200;
+  }
+  
+  .btn-outline {
+    @apply inline-flex items-center justify-center px-6 py-3 border-2 border-primary-600 text-primary-600 font-semibold rounded-lg
+           hover:bg-primary-600 hover:text-white transition-all duration-200;
+  }
+  
+  .section-title {
+    @apply text-3xl md:text-4xl lg:text-5xl font-bold text-secondary-900;
+  }
+  
+  .section-subtitle {
+    @apply text-lg md:text-xl text-secondary-600 mt-4;
+  }
+  
+  .card {
+    @apply bg-white rounded-xl shadow-card overflow-hidden transition-all duration-300 
+           hover:shadow-industrial hover:-translate-y-1;
+  }
+  
+  .card-industrial {
+    @apply bg-secondary-800 text-white rounded-xl p-6 border-l-4 border-primary-500;
+  }
+  
+  .gradient-overlay {
+    @apply absolute inset-0 bg-gradient-to-r from-industrial-dark/90 to-industrial-dark/70;
+  }
+  
+  .industrial-badge {
+    @apply inline-flex items-center px-3 py-1 bg-primary-600 text-white text-sm font-semibold rounded;
+  }
+}
+
+/* Custom theme colors - Industrial theme */
 :root {
-  --color-primary-600: #22c55e;
-  --color-primary-700: #16a34a;
+  --color-primary-500: #22c55e;
+  --color-primary-600: #16a34a;
+  --color-primary-700: #15803d;
+  
   --color-secondary-50: #f8fafc;
   --color-secondary-100: #f1f5f9;
   --color-secondary-200: #e2e8f0;
@@ -13,6 +74,7 @@
   --color-secondary-700: #334155;
   --color-secondary-800: #1e293b;
   --color-secondary-900: #0f172a;
+  
   --color-accent-500: #eab308;
 }