Adjust spacing for categories in the video grid display

Modify the bottom margin of category rows in `netflix-grid.tsx` from `mb-3` to `mb-2` for the second category onwards.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 074b0e4c-6171-43bd-aa98-f9e04623ca14
Replit-Commit-Checkpoint-Type: full_checkpoint
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client/src/components/netflix-grid.tsx

@@ -107,7 +107,7 @@ export default function NetflixGrid({ videos, isLoading }: NetflixGridProps) {
     <>
       <div>
         {categories.map((category, categoryIndex) => (
-          <div key={categoryIndex} className={`${categoryIndex === 0 ? 'mt-2 mb-4' : 'mb-3'}`}>
+          <div key={categoryIndex} className={`${categoryIndex === 0 ? 'mt-2 mb-4' : 'mb-2'}`}>
             <CategoryRow
               category={category}
               onVideoClick={handleVideoClick}