diff --git a/web/index.php b/web/index.php
index cb645f142..efcd84dc1 100644
--- a/web/index.php
+++ b/web/index.php
@@ -58,7 +58,9 @@ if ( $_SERVER['REQUEST_METHOD'] == 'OPTIONS' ) {
   return;
 }
 
-if ( isset($_GET['skin']) ) {
+if ( defined('ZM_FORCE_SKIN_DEFAULT') ) {
+  $skin = ZM_FORCE_SKIN_DEFAULT;
+} else if ( isset($_GET['skin']) ) {
   $skin = $_GET['skin'];
 } else if ( isset($_COOKIE['zmSkin']) ) {
   $skin = $_COOKIE['zmSkin'];
@@ -76,7 +78,9 @@ if (!is_dir('skins/'.$skin) ) {
   }
 }
 global $css;
-if ( isset($_GET['css']) ) {
+if (defined('ZM_FORCE_CSS_DEFAULT')) {
+  $css = ZM_FORCE_CSS_DEFAULT;
+} else if ( isset($_GET['css']) ) {
   $css = $_GET['css'];
 } else if ( isset($_COOKIE['zmCSS']) ) {
   $css = $_COOKIE['zmCSS'];
diff --git a/web/skins/classic/includes/functions.php b/web/skins/classic/includes/functions.php
index 42cc868d0..eecdd58f4 100644
--- a/web/skins/classic/includes/functions.php
+++ b/web/skins/classic/includes/functions.php
@@ -91,7 +91,12 @@ function xhtmlHeaders($file, $title) {
   <meta name="viewport" content="width=device-width, initial-scale=1">
   <title><?php echo validHtmlStr(ZM_WEB_TITLE_PREFIX) . ' - ' . validHtmlStr($title) ?></title>
 <?php
-if ( file_exists("skins/$skin/css/$css/graphics/favicon.ico") ) {
+if (defined('ZM_WEB_FAVICON')) {
+  echo '
+  <link rel="icon" type="image/ico" href="'.ZM_WEB_FAVICON.'"/>
+  <link rel="shortcut icon" href="'.ZM_WEB_FAVICON.'"/>
+';
+} else if ( file_exists("skins/$skin/css/$css/graphics/favicon.ico") ) {
   echo "
   <link rel=\"icon\" type=\"image/ico\" href=\"skins/$skin/css/$css/graphics/favicon.ico\"/>
   <link rel=\"shortcut icon\" href=\"skins/$skin/css/$css/graphics/favicon.ico\"/>
diff --git a/web/skins/classic/views/options.php b/web/skins/classic/views/options.php
index ddfc84db1..246b06f57 100644
--- a/web/skins/classic/views/options.php
+++ b/web/skins/classic/views/options.php
@@ -26,6 +26,7 @@ if (!canView('System')) {
 $canEdit = canEdit('System');
 
 $tabs = array();
+if (!defined('ZM_FORCE_CSS_DEFAULT') or !defined('ZM_FORCE_SKIN_DEFAULT'))
 $tabs['skins'] = translate('Display');
 $tabs['system'] = translate('System');
 $tabs['config'] = translate('Config');
@@ -179,8 +180,14 @@ foreach (array_map('basename', glob('skins/'.$skin.'/css/*', GLOB_ONLYDIR)) as $
     ];
   } else if ($tab == 'system') {
 //    $configCats[$tab]['ZM_LANG_DEFAULT']['Hint'] = join('|', getLanguages());
-    $configCats[$tab]['ZM_SKIN_DEFAULT']['Hint'] = join('|', array_map('basename', glob('skins/*',GLOB_ONLYDIR)));
-    $configCats[$tab]['ZM_CSS_DEFAULT']['Hint'] = join('|', array_map ( 'basename', glob('skins/'.ZM_SKIN_DEFAULT.'/css/*',GLOB_ONLYDIR) ));
+    if (defined('ZM_FORCE_SKIN_DEFAULT'))
+      $configCats[$tab]['ZM_SKIN_DEFAULT']['Hint'] = ZM_FORCE_SKIN_DEFAULT;
+    else
+      $configCats[$tab]['ZM_SKIN_DEFAULT']['Hint'] = join('|', array_map('basename', glob('skins/*',GLOB_ONLYDIR)));
+    if (defined('ZM_FORCE_CSS_DEFAULT'))
+      $configCats[$tab]['ZM_CSS_DEFAULT']['Hint'] = ZM_FORCE_CSS_DEFAULT;
+    else
+      $configCats[$tab]['ZM_CSS_DEFAULT']['Hint'] = join('|', array_map ( 'basename', glob('skins/'.ZM_SKIN_DEFAULT.'/css/*',GLOB_ONLYDIR) ));
     $configCats[$tab]['ZM_BANDWIDTH_DEFAULT']['Hint'] = $bandwidth_options;
 
 // create new multidim array for languages (code1|translation)