Add landing pages library with comprehensive components and demos

🤖 Generated with [Claude Code](https://claude.ai/code)

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

projects/ui-landing-pages/src/lib/components/templates/saas-template.component.scss

@@ -0,0 +1,45 @@
+@use '../../../../../ui-design-system/src/styles/semantic/index' as *;
+
+.ui-lp-saas-template {
+  min-height: 100vh;
+  display: flex;
+  flex-direction: column;
+  
+  &__main {
+    flex: 1;
+    
+    // Alternating background colors for sections
+    > *:nth-child(odd) {
+      background: $semantic-color-surface-primary;
+    }
+    
+    > *:nth-child(even) {
+      background: $semantic-color-surface-secondary;
+    }
+    
+    // Override for hero to maintain gradient/special background
+    > ui-lp-hero {
+      background: unset;
+    }
+  }
+  
+  // Ensure proper spacing between sections
+  section + section {
+    border-top: 1px solid $semantic-color-border-subtle;
+  }
+  
+  // Responsive adjustments
+  @media (max-width: $semantic-breakpoint-sm - 1) {
+    &__main {
+      // Reduce alternating backgrounds on mobile for better readability
+      > * {
+        background: $semantic-color-surface-primary !important;
+      }
+      
+      section + section {
+        border-top: none;
+        margin-top: $semantic-spacing-layout-section-sm;
+      }
+    }
+  }
+}