diff --git a/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor b/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
index 9f5a7293..8253d971 100644
--- a/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
+++ b/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
@@ -131,14 +131,6 @@
                     @if (_pdfLoaded && _showThumbnails) {
                         <!-- PDF Thumbnail Sidebar -->
                         <div class="pdf-thumbnails">
-                            <div class="pdf-thumbnails__header">
-                                <span class="pdf-thumbnails__title">Seiten</span>
-                                <button class="pdf-thumbnails__close" @onclick="ToggleThumbnails" title="Seitenleiste schließen">
-                                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" viewBox="0 0 16 16">
-                                        <path d="M4.646 4.646a.5.5 0 0 1 .708 0L8 7.293l2.646-2.647a.5.5 0 0 1 .708.708L8.707 8l2.647 2.646a.5.5 0 0 1-.708.708L8 8.707l-2.646 2.647a.5.5 0 0 1-.708-.708L7.293 8 4.646 5.354a.5.5 0 0 1 0-.708z"/>
-                                    </svg>
-                                </button>
-                            </div>
                             <div class="pdf-thumbnails__content">
                                 @for (int i = 1; i <= _totalPages; i++) {
                                     var pageNum = i;
diff --git a/EnvelopeGenerator.ReceiverUI/wwwroot/css/envelope-viewer.css b/EnvelopeGenerator.ReceiverUI/wwwroot/css/envelope-viewer.css
index 82913155..1b532cfb 100644
--- a/EnvelopeGenerator.ReceiverUI/wwwroot/css/envelope-viewer.css
+++ b/EnvelopeGenerator.ReceiverUI/wwwroot/css/envelope-viewer.css
@@ -76,45 +76,6 @@
     flex-shrink: 0;
 }
 
-.pdf-thumbnails--visible {
-    /* No longer needed - visibility controlled by @if in Razor */
-}
-
-.pdf-thumbnails__header {
-    display: flex;
-    align-items: center;
-    justify-content: space-between;
-    padding: 1rem 1.25rem;
-    border-bottom: 2px solid rgba(126, 34, 206, 0.1);
-    flex-shrink: 0;
-}
-
-.pdf-thumbnails__title {
-    font-size: 0.875rem;
-    font-weight: 700;
-    color: #1e293b;
-    letter-spacing: 0.025em;
-    text-transform: uppercase;
-}
-
-.pdf-thumbnails__close {
-    background: transparent;
-    border: none;
-    cursor: pointer;
-    padding: 0.375rem;
-    border-radius: 6px;
-    color: #64748b;
-    transition: all 0.2s ease;
-    display: flex;
-    align-items: center;
-    justify-content: center;
-}
-
-.pdf-thumbnails__close:hover {
-    background: rgba(126, 34, 206, 0.1);
-    color: #7e22ce;
-}
-
 .pdf-thumbnails__content {
     flex: 1;
     overflow-y: auto;