diff --git a/frontend/css/style.css b/frontend/css/style.css
index 0eb3c9cde..52ac4f6e1 100644
--- a/frontend/css/style.css
+++ b/frontend/css/style.css
@@ -2059,19 +2059,45 @@ display: grid;
 }
 
 .close-genre-modal {
-    background: none;
-    border: none;
+    width: 44px;
+    height: 44px;
+    background: transparent;
+    border: 1px solid transparent;
     font-size: 1.5rem;
-    color: var(--text-main);
+    color: var(--text-muted, rgba(0, 0, 0, 0.6));
     cursor: pointer;
-    padding: 0.5rem;
+    padding: 0;
+    line-height: 1;
     border-radius: 50%;
-    transition: all 0.2s ease;
+    flex-shrink: 0;
+    aspect-ratio: 1 / 1;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    transition: all 0.25s cubic-bezier(0.25, 0.46, 0.45, 0.94);
 }
 
 .close-genre-modal:hover {
-    background: rgba(0, 0, 0, 0.1);
-    transform: rotate(90deg);
+    background-color: rgba(220, 53, 69, 0.08);
+    color: #c9302c;
+    transform: scale(1.04);
+}
+
+.close-genre-modal:active {
+    transform: scale(0.96);
+}
+
+[data-theme="night"] .close-genre-modal {
+    background-color: transparent;
+    border: 1px solid transparent;
+    color: rgba(255, 255, 255, 0.7);
+}
+
+[data-theme="night"] .close-genre-modal:hover {
+    background-color: rgba(255, 99, 104, 0.12);
+    border-color: rgba(255, 99, 104, 0.25);
+    color: #ffb3b3;
+    transform: scale(1.04);
 }
 
 .genre-modal-body {
@@ -2641,28 +2667,48 @@ display: grid;
 
 .modal-close-btn {
     position: absolute;
-    top: 10px;
-    right: 10px;
+    top: 15px;
+    right: 15px;
     width: 36px;
     height: 36px;
-    font-size: 1rem;
     border-radius: 50%;
-    background: var(--glass-bg);
-    border: 1px solid var(--glass-border);
-    cursor: pointer;
+    flex-shrink: 0;
+    aspect-ratio: 1 / 1;
     display: flex;
     align-items: center;
     justify-content: center;
-    font-size: 1.5rem;
-    color: var(--text-muted);
-    transition: all 0.3s ease;
-    z-index: 10;
+    padding: 0;
+    font-size: 1.25rem;
+    line-height: 1;
+    cursor: pointer;
+    z-index: 100;
+    transition: all 0.25s cubic-bezier(0.25, 0.46, 0.45, 0.94);
+    background-color: transparent;
+    border: 1px solid transparent; 
+    color: var(--text-muted, rgba(0, 0, 0, 0.6));
 }
 
 .modal-close-btn:hover {
-    background: var(--accent-gold);
-    color: white;
-    transform: rotate(90deg);
+    background-color: rgba(220, 53, 69, 0.08);
+    color: #c9302c;
+    transform: scale(1.04);
+}
+
+.modal-close-btn:active {
+    transform: scale(0.96);
+}
+
+[data-theme="night"] .modal-close-btn {
+    background-color: transparent;
+    border: 1px solid transparent;
+    color: rgba(255, 255, 255, 0.7);
+}
+
+[data-theme="night"] .modal-close-btn:hover {
+    background-color: rgba(255, 99, 104, 0.12);
+    border-color: rgba(255, 99, 104, 0.25);
+    color: #ffb3b3;
+    transform: scale(1.04);
 }
 
 .book-detail-grid {
@@ -3763,30 +3809,7 @@ display: grid;
     pointer-events: auto;
 }
 
-#modal-close-btn {
-    position: absolute;
-    top: 10px;
-    right: 10px;
-    background: rgba(255, 255, 255, 0.1);
-    border: 1px solid rgba(255, 255, 255, 0.2);
-    color: #fff;
-    width: 32px;
-    height: 32px;
-    border-radius: 50%;
-    font-size: 0.9rem;
-    cursor: pointer;
-    z-index: 2005;
-    transition: all 0.3s ease;
-    pointer-events: auto;
-    display: flex;
-    align-items: center;
-    justify-content: center;
-}
 
-#modal-close-btn:hover {
-    background: rgba(255, 255, 255, 0.25);
-    transform: rotate(90deg);
-}
 
 .book-expanded-layout {
     display: flex;
@@ -4263,14 +4286,7 @@ display: grid;
         max-height: 300px;
     }
 
-    #modal-close-btn {
-        top: 15px;
-        right: 15px;
-        background: rgba(0, 0, 0, 0.5);
-        /* Contrast on white if scrolled */
-        position: fixed;
-        /* Keep it visible */
-    }
+
 }
 
 /* 404 Page Styles */
diff --git a/frontend/css/style_main.css b/frontend/css/style_main.css
index 2f6a1c8b6..2b8201b74 100644
Binary files a/frontend/css/style_main.css and b/frontend/css/style_main.css differ
diff --git a/frontend/pages/library.html b/frontend/pages/library.html
index 0f3b3642d..2c865f3e6 100644
--- a/frontend/pages/library.html
+++ b/frontend/pages/library.html
@@ -286,8 +286,8 @@ <h1 id="selected-collection-name" style="font-family: 'Playfair Display', serif;
 
         <!-- Book Detail Modal -->
         <div class="book-detail-modal" id="book-detail-modal">
-            <button class="modal-close-btn" id="modal-close-btn" title="Close details">
-                <i class="fa-solid fa-times"></i>
+            <button class="modal-close-btn" id="modal-close-btn" aria-label="Close details" title="Close details">
+                <i class="fa-solid fa-xmark"></i>
             </button>
             <div class="book-detail-content">
                 <div class="book-expanded-layout">