diff --git a/backend/workers/thumbnails.go b/backend/workers/thumbnails.go
index d26ca4b..9cee374 100644
--- a/backend/workers/thumbnails.go
+++ b/backend/workers/thumbnails.go
@@ -148,7 +148,7 @@ func (m *ThumbnailManager) worker(id int) {
 			err = generateVideoThumbnail(fullSourcePath, destPath)
 		} else if strings.HasPrefix(job.MimeType, "audio/") {
 			err = generateAudioThumbnail(fullSourcePath, destPath)
-		} else if strings.HasSuffix(job.FilePath, ".docx") || strings.HasSuffix(job.FilePath, ".pptx") || strings.HasSuffix(job.FilePath, ".xlsx") {
+		} else if strings.HasSuffix(strings.ToLower(job.FilePath), ".pdf") || strings.HasSuffix(strings.ToLower(job.FilePath), ".docx") || strings.HasSuffix(strings.ToLower(job.FilePath), ".pptx") || strings.HasSuffix(strings.ToLower(job.FilePath), ".xlsx") {
 			err = generateOfficeThumbnail(job.FilePath, destPath, m.Config)
 		} else {
 			continue
diff --git a/frontend/src/components/FileExplorer.tsx b/frontend/src/components/FileExplorer.tsx
index 40dde0c..3dc1678 100644
--- a/frontend/src/components/FileExplorer.tsx
+++ b/frontend/src/components/FileExplorer.tsx
@@ -1240,7 +1240,7 @@ export default function FileExplorer({ onLogout }: FileExplorerProps) {
     })();
 
     if (isMedia && file.checksum && viewMode === 'grid') {
-      const docType = file.name.endsWith('.docx') ? 'docs' : file.name.endsWith('.pptx') ? 'slides' : (file.name.endsWith('.xlsx') || file.name.endsWith('.xls')) ? 'sheets' : file.name.endsWith('.pdf') ? 'pdf' : null;
+      const docType = file.name.endsWith('.docx') ? 'docs' : file.name.endsWith('.pptx') ? 'slides' : (file.name.endsWith('.xlsx') || file.name.endsWith('.xls')) ? 'sheets' : ext === 'pdf' ? 'pdf' : null;
       // Use fallbackIcon for PDF too so it shows "PDF" text while loading
       const currentFallback = ext === 'pdf' ? (
         <div className={`${large ? 'w-20 h-20 rounded-2xl text-2xl' : 'w-5 h-5 rounded text-[6px] flex-shrink-0 aspect-square'} flex items-center justify-center font-black tracking-tighter shadow-sm text-white bg-[#ea4335]`}>
diff --git a/frontend/src/components/ThumbnailImage.tsx b/frontend/src/components/ThumbnailImage.tsx
index b2782fb..ae97ec8 100644
--- a/frontend/src/components/ThumbnailImage.tsx
+++ b/frontend/src/components/ThumbnailImage.tsx
@@ -34,10 +34,10 @@ export default function ThumbnailImage({ checksum, fallbackIcon, downloadToken,
       key={key}
       src={downloadToken ? `${api.getThumbnailUrl(checksum, downloadToken)}${errorCount > 0 ? `&t=${key}` : ''}` : ''}
       alt=""
-      className={`object-contain ${
+      className={`${
         docType === 'pdf' ? 'w-full h-full object-cover object-top' : 
         docType ? 'w-full h-full object-cover mix-blend-multiply' : 
-        'w-full h-full'
+        'object-contain w-full h-full'
       }`}
       style={{ display: showFallback ? 'none' : 'block' }}
       onError={(e) => {