diff --git a/bettercf/core/renderer.js b/bettercf/core/renderer.js
index 00217e1..b437fc8 100644
--- a/bettercf/core/renderer.js
+++ b/bettercf/core/renderer.js
@@ -134,10 +134,12 @@
         const theme = this._themes.find(t => t.fileName === this._savedThemeFileName);
         if (theme) {
           this.applyTheme(theme, false);
+          document.documentElement.classList.add('bcf-client-theme-selected');
         } else {
           // Stored theme file not found
           this._savedThemeFileName = null;
           this._activeThemeFileName = null;
+          document.documentElement.classList.remove('bcf-client-theme-selected');
         }
       }
 
@@ -235,14 +237,20 @@
         }
 
         /* ═══ Mutual Exclusivity ═══ */
-        /* When a BetterCF client theme is active, hide active checkmark & active indicator on native theme cards */
-        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active .sprite-icon {
+        /* When a BetterCF client theme is active/selected, hide active checkmark & active indicator on native theme cards when not hovered */
+        html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon,
+        html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon,
+        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon {
           opacity: 0 !important;
         }
-        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active .thumb-icon {
+        html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon,
+        html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon,
+        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon {
           background-color: transparent !important;
         }
-        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active {
+        html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover),
+        html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover),
+        html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) {
           outline: none !important;
           border-color: transparent !important;
           box-shadow: none !important;
@@ -318,10 +326,13 @@
       if (save) {
         this._savedThemeFileName = theme.fileName;
         this._isPreviewing = false;
+        document.documentElement.classList.add('bcf-client-theme-selected');
         try {
           localStorage.setItem('bcf_active_custom_theme', theme.fileName);
           ipc?.invoke?.('bcf:settings:set', 'activeCustomTheme', theme.fileName);
         } catch {}
+      } else if (this._savedThemeFileName) {
+        document.documentElement.classList.add('bcf-client-theme-selected');
       }
 
       console.log(`[BetterCF] Applied custom theme: ${theme.name} (${theme.fileName}) [save=${save}]`);
@@ -338,10 +349,13 @@
       if (save) {
         this._savedThemeFileName = null;
         this._isPreviewing = false;
+        document.documentElement.classList.remove('bcf-client-theme-selected', 'bcf-native-preview-active');
         try {
           localStorage.removeItem('bcf_active_custom_theme');
           ipc?.invoke?.('bcf:settings:set', 'activeCustomTheme', null);
         } catch {}
+      } else if (!this._savedThemeFileName) {
+        document.documentElement.classList.remove('bcf-client-theme-selected', 'bcf-native-preview-active');
       }
 
       console.log(`[BetterCF] Reverted to native theme [save=${save}].`);
@@ -365,6 +379,7 @@
         }
       }
       this.removeTheme(false);
+      document.documentElement.classList.remove('bcf-client-theme-selected', 'bcf-native-preview-active');
     },
 
     suspendForNativePreview() {
@@ -375,17 +390,20 @@
           this._styleElement.disabled = true;
         }
         document.documentElement.classList.remove('bcf-custom-theme-active');
+        document.documentElement.classList.add('bcf-native-preview-active');
       }
     },
 
     resumeFromNativePreview() {
       if (!this._isSuspendedForNative) return;
       this._isSuspendedForNative = false;
+      document.documentElement.classList.remove('bcf-native-preview-active');
       if (this._savedThemeFileName) {
         if (this._styleElement) {
           this._styleElement.disabled = false;
         }
         document.documentElement.classList.add('bcf-custom-theme-active');
+        document.documentElement.classList.add('bcf-client-theme-selected');
       }
     },
 
@@ -415,6 +433,7 @@
       const nativeThumb = e.target.closest('.theme-thumb:not(.bcf-theme-thumb)');
       if (nativeThumb) {
         ThemeManager._isSuspendedForNative = false;
+        document.documentElement.classList.remove('bcf-native-preview-active');
         if (ThemeManager.getActiveThemeName()) {
           ThemeManager.removeTheme(true);
           const grid = document.querySelector('#bcf-custom-themes-grid');
diff --git a/patcher/patch_core.py b/patcher/patch_core.py
index 65b3898..88c76f2 100644
--- a/patcher/patch_core.py
+++ b/patcher/patch_core.py
@@ -559,13 +559,19 @@ owadview,
 }
 
 /* Mutual exclusivity: hide checkmark on native theme cards when a client theme is active */
-html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active .sprite-icon {
+html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon,
+html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon,
+html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .sprite-icon {
   opacity: 0 !important;
 }
-html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active .thumb-icon {
+html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon,
+html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon,
+html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) .thumb-icon {
   background-color: transparent !important;
 }
-html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active {
+html.bcf-client-theme-selected .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover),
+html.bcf-native-preview-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover),
+html.bcf-custom-theme-active .settings-themes-view .theme-thumb:not(.bcf-theme-thumb).is-active:not(:hover) {
   outline: none !important;
   border-color: transparent !important;
   box-shadow: none !important;
@@ -594,9 +600,11 @@ html.bcf-custom-theme-active .pixelforge-skin :not(.highlighted-project-containe
 }
 """
             css_text = desktop_css.read_text(encoding="utf-8")
-            if "/* ═══ BetterCurseForge Zero-Ad Rules ═══ */" not in css_text:
-                desktop_css.write_text(css_text + "\n" + css_rules, encoding="utf-8")
-                log_callback("[+] Injected zero-ad and theme CSS rules into desktop.css")
+            if "/* ═══ BetterCurseForge Zero-Ad Rules ═══ */" in css_text:
+                idx = css_text.find("/* ═══ BetterCurseForge Zero-Ad Rules ═══ */")
+                css_text = css_text[:idx].rstrip()
+            desktop_css.write_text(css_text + "\n" + css_rules, encoding="utf-8")
+            log_callback("[+] Injected zero-ad and theme CSS rules into desktop.css")
 
         # 3. Copy BetterCF runtime into asar
         bcf_src = find_bettercf_source()