diff --git a/packages/fcl-css/src/fpcssresolver.pas b/packages/fcl-css/src/fpcssresolver.pas
index 4600f9725b..3937dfb3f1 100644
--- a/packages/fcl-css/src/fpcssresolver.pas
+++ b/packages/fcl-css/src/fpcssresolver.pas
@@ -135,14 +135,14 @@ const
   CSSPseudoID_FirstOfType = CSSPseudoID_OnlyChild+1; // :first-of-type
   CSSPseudoID_LastOfType = CSSPseudoID_FirstOfType+1; // :last-of-type
   CSSPseudoID_OnlyOfType = CSSPseudoID_LastOfType+1; // :only-of-type
-  CSSCallID_Not = CSSPseudoID_OnlyOfType+1; // :nth-child
-  CSSCallID_Is = CSSCallID_Not+1; // :nth-child
-  CSSCallID_Where = CSSCallID_Is+1; // :nth-child
-  CSSCallID_Has = CSSCallID_Where+1; // :nth-child
-  CSSCallID_NthChild = CSSCallID_Has+1; // :nth-child
-  CSSCallID_NthLastChild = CSSCallID_NthChild+1; // :nth-child
-  CSSCallID_NthOfType = CSSCallID_NthLastChild+1; // :nth-child
-  CSSCallID_NthLastOfType = CSSCallID_NthOfType+1; // :nth-child
+  CSSCallID_Not = CSSPseudoID_OnlyOfType+1; // :not()
+  CSSCallID_Is = CSSCallID_Not+1; // :is()
+  CSSCallID_Where = CSSCallID_Is+1; // :where()
+  CSSCallID_Has = CSSCallID_Where+1; // :has()
+  CSSCallID_NthChild = CSSCallID_Has+1; // :nth-child(n)
+  CSSCallID_NthLastChild = CSSCallID_NthChild+1; // :nth-last-child(n)
+  CSSCallID_NthOfType = CSSCallID_NthLastChild+1; // :nth-of-type(n)
+  CSSCallID_NthLastOfType = CSSCallID_NthOfType+1; // :nth-last-of-type(n)
   CSSLastPseudoID = CSSCallID_NthLastOfType;
 
 const
@@ -201,8 +201,7 @@ type
     function GetCSSPreviousOfType: ICSSNode;
     function HasCSSAttribute(const AttrID: TCSSNumericalID): boolean;
     function GetCSSAttribute(const AttrID: TCSSNumericalID): TCSSString;
-    function HasCSSPseudo(const AttrID: TCSSNumericalID): boolean;
-    function GetCSSPseudo(const AttrID: TCSSNumericalID): TCSSString;
+    function HasCSSPseudoClass(const AttrID: TCSSNumericalID): boolean;
     function GetCSSEmpty: boolean;
     function GetCSSDepth: integer;
     procedure SetCSSValue(AttrID: TCSSNumericalID; Value: TCSSElement);
@@ -213,7 +212,7 @@ type
   TCSSNumericalIDKind = (
     nikType,
     nikAttribute,
-    nikPseudoAttribute
+    nikPseudoClass
     );
   TCSSNumericalIDKinds = set of TCSSNumericalIDKind;
 
@@ -221,7 +220,7 @@ const
   CSSNumericalIDKindNames: array[TCSSNumericalIDKind] of TCSSString = (
     'Type',
     'Attribute',
-    'PseudoAttribute'
+    'PseudoClass'
     );
 
 type
@@ -732,7 +731,7 @@ begin
   if OnlySpecifity then
     exit(CSSSpecifityClass);
   Result:=CSSSpecifityNoMatch;
-  PseudoID:=ResolveIdentifier(aPseudoClass,nikPseudoAttribute);
+  PseudoID:=ResolveIdentifier(aPseudoClass,nikPseudoClass);
   case PseudoID of
   CSSIDNone:
     LogWarning(croErrorOnUnknownName in Options,20220911205605,'Unknown CSS selector pseudo attribute name "'+aPseudoClass.Name+'"',aPseudoClass);
@@ -763,7 +762,7 @@ begin
         and (TestNode.GetCSSPreviousOfType=nil) then
       Result:=CSSSpecifityClass;
   else
-    if TestNode.GetCSSPseudo(PseudoID)<>'' then
+    if TestNode.HasCSSPseudoClass(PseudoID) then
       Result:=CSSSpecifityClass;
   end;
 end;
@@ -1763,7 +1762,7 @@ begin
       'class': Result:=CSSAttributeID_Class;
       'all': Result:=CSSAttributeID_All;
       end;
-    nikPseudoAttribute:
+    nikPseudoClass:
       begin
       aName:=lowercase(aName); // pseudo attributes are ASCII case insensitive
       case aName of
diff --git a/packages/fcl-css/tests/tccssresolver.pp b/packages/fcl-css/tests/tccssresolver.pp
index 1326ba8842..198f0ee71b 100644
--- a/packages/fcl-css/tests/tccssresolver.pp
+++ b/packages/fcl-css/tests/tccssresolver.pp
@@ -47,6 +47,7 @@ const
     );
 
   DemoAttrIDBase = 100;
+  DemoPseudoClassIDBase = 100;
 
 type
   TDemoPseudoClass = (
@@ -55,6 +56,13 @@ type
     );
   TDemoPseudoClasses = set of TDemoPseudoClass;
 
+const
+  DemoPseudoClassNames: array[TDemoPseudoClass] of string = (
+    // case sensitive!
+    ':active',
+    ':hover'
+    );
+
 type
 
   { TDemoNode }
@@ -63,7 +71,9 @@ type
   private
     class var FAttributeInitialValues: array[TDemoNodeAttribute] of string;
   private
+    FActive: boolean;
     FAttributeValues: array[TDemoNodeAttribute] of string;
+    FHover: boolean;
     FNodes: TFPObjectList; // list of TDemoNode
     FCSSClasses: TStrings;
     FParent: TDemoNode;
@@ -72,7 +82,9 @@ type
     function GetAttribute(AIndex: TDemoNodeAttribute): string;
     function GetNodeCount: integer;
     function GetNodes(Index: integer): TDemoNode;
+    procedure SetActive(const AValue: boolean);
     procedure SetAttribute(AIndex: TDemoNodeAttribute; const AValue: string);
+    procedure SetHover(const AValue: boolean);
     procedure SetParent(const AValue: TDemoNode);
     procedure SetStyleElements(const AValue: TCSSElement);
     procedure SetStyle(const AValue: string);
@@ -104,8 +116,7 @@ type
     function GetCSSAttributeClass: TCSSString; virtual;
     function HasCSSAttribute(const AttrID: TCSSNumericalID): boolean; virtual;
     function GetCSSAttribute(const AttrID: TCSSNumericalID): TCSSString; virtual;
-    function HasCSSPseudo(const {%H-}AttrID: TCSSNumericalID): boolean; virtual;
-    function GetCSSPseudo(const {%H-}AttrID: TCSSNumericalID): TCSSString; virtual;
+    function HasCSSPseudoClass(const {%H-}AttrID: TCSSNumericalID): boolean; virtual;
     function GetCSSEmpty: boolean; virtual;
     function GetCSSDepth: integer; virtual;
     property Parent: TDemoNode read FParent write SetParent;
@@ -123,6 +134,10 @@ type
     property Display: string index naDisplay read GetAttribute write SetAttribute;
     property Color: string index naColor read GetAttribute write SetAttribute;
     property Attribute[Attr: TDemoNodeAttribute]: string read GetAttribute write SetAttribute;
+    // CSS pseudo classes
+    property Active: boolean read FActive write SetActive;
+    property Hover: boolean read FHover write SetHover;
+    function HasPseudoClass(PseudoClass: TDemoPseudoClass): boolean;
   end;
   TDemoNodeClass = class of TDemoNode;
 
@@ -208,9 +223,9 @@ type
     // Test list spaces "div, button ,span {}"
     procedure Test_Selector_Id;
     procedure Test_Selector_Class;
-    procedure Test_Selector_ClassClass; // ToDo and combinator
-    procedure Test_Selector_ClassSpaceClass; // ToDo descendant combinator
-    procedure Test_Selector_TypeCommaType; // or combinator
+    procedure Test_Selector_ClassClass; // AND combinator
+    procedure Test_Selector_ClassSpaceClass; // Descendant combinator
+    procedure Test_Selector_TypeCommaType; // OR combinator
     procedure Test_Selector_ClassGTClass; // child combinator
     procedure Test_Selector_TypePlusType; // adjacent sibling combinator
     procedure Test_Selector_TypeTildeType; // general sibling combinator
@@ -224,7 +239,7 @@ type
     procedure Test_Selector_AttributeContainsSubstring;
     // ToDo: "all"
 
-    // pseudo attributes
+    // pseudo classes
     procedure Test_Selector_Root;
     procedure Test_Selector_Empty;
     procedure Test_Selector_FirstChild;
@@ -243,8 +258,12 @@ type
     procedure Test_Selector_Where;
     // ToDo: div:has(>img)
     // ToDo: div:has(+img)
+    // ToDo: :dir()
     // ToDo: :lang()
 
+    // custom pseudo classes
+    procedure Test_Selector_Hover;
+
     // inline style
     procedure Test_InlineStyle;
 
@@ -1232,6 +1251,39 @@ begin
   AssertEquals('Div2.Left','2px',Div2.Left);
 end;
 
+procedure TTestCSSResolver.Test_Selector_Hover;
+var
+  Div1, Div11: TDemoDiv;
+  Button1: TDemoButton;
+begin
+  Doc.Root:=TDemoNode.Create(nil);
+
+  Div1:=TDemoDiv.Create(Doc);
+  Div1.Parent:=Doc.Root;
+  Div1.Hover:=true;
+
+  Button1:=TDemoButton.Create(Doc);
+  Button1.Parent:=Div1;
+  Button1.Hover:=true;
+
+  Div11:=TDemoDiv.Create(Doc);
+  Div11.Parent:=Div1;
+
+  Doc.Style:=LinesToStr([
+  ':hover { left: 1px; }',
+  'button:hover { top: 2px; }',
+  '']);
+  Doc.ApplyStyle;
+  AssertEquals('Root.Left','',Doc.Root.Left);
+  AssertEquals('Root.Top','',Doc.Root.Top);
+  AssertEquals('Div1.Left','1px',Div1.Left);
+  AssertEquals('Div1.Top','',Div1.Top);
+  AssertEquals('Button1.Left','1px',Button1.Left);
+  AssertEquals('Button1.Top','2px',Button1.Top);
+  AssertEquals('Div11.Left','',Div11.Left);
+  AssertEquals('Div11.Top','',Div11.Top);
+end;
+
 procedure TTestCSSResolver.Test_InlineStyle;
 var
   Div1: TDemoDiv;
@@ -1356,14 +1408,17 @@ end;
 constructor TDemoDocument.Create(AOwner: TComponent);
 var
   Attr: TDemoNodeAttribute;
-  TypeIDs, AttributeIDs: TCSSNumericalIDs;
+  TypeIDs, AttributeIDs, PseudoClassIDs: TCSSNumericalIDs;
   NumKind: TCSSNumericalIDKind;
   AttrID: TCSSNumericalID;
+  PseudoClass: TDemoPseudoClass;
 begin
   inherited Create(AOwner);
 
   for NumKind in TCSSNumericalIDKind do
     FNumericalIDs[NumKind]:=TCSSNumericalIDs.Create(NumKind);
+
+  // register all css types
   TypeIDs:=FNumericalIDs[nikType];
   TypeIDs['*']:=CSSTypeID_Universal;
   if TypeIDs['*']<>CSSTypeID_Universal then
@@ -1373,22 +1428,38 @@ begin
   TypeIDs[TDemoDiv.CSSTypeName]:=TDemoDiv.CSSTypeID;
   TypeIDs[TDemoButton.CSSTypeName]:=TDemoButton.CSSTypeID;
 
+  // register all css attribute
   AttributeIDs:=FNumericalIDs[nikAttribute];
   AttributeIDs['all']:=CSSAttributeID_All;
+  // add basic element attributes
   AttrID:=DemoAttrIDBase;
   for Attr in TDemoNodeAttribute do
   begin
     AttributeIDs[DemoAttributeNames[Attr]]:=AttrID;
     inc(AttrID);
   end;
+  // add button caption attribute
   TDemoButton.CSSCaptionID:=AttrID;
   AttributeIDs['caption']:=AttrID;
   inc(AttrID);
 
+  // register css pseudo attributes
+  PseudoClassIDs:=FNumericalIDs[nikPseudoClass];
+  AttrID:=DemoPseudoClassIDBase;
+  for PseudoClass in TDemoPseudoClass do
+  begin
+    PseudoClassIDs[DemoPseudoClassNames[PseudoClass]]:=AttrID;
+    inc(AttrID);
+  end;
+  if PseudoClassIDs[DemoPseudoClassNames[pcHover]]<>DemoPseudoClassIDBase+ord(pcHover) then
+    raise Exception.Create('20231008232201');
+
+  // create the css resolver
   FCSSResolver:=TCSSResolver.Create(nil);
   for NumKind in TCSSNumericalIDKind do
     CSSResolver.NumericalIDs[NumKind]:=FNumericalIDs[NumKind];
 
+  // create a demo root node
   Root:=TDemoNode.Create(Self);
   Root.Name:='Root';
 end;
@@ -1453,6 +1524,12 @@ begin
   FAttributeValues[AIndex]:=AValue;
 end;
 
+procedure TDemoNode.SetHover(const AValue: boolean);
+begin
+  if FHover=AValue then Exit;
+  FHover:=AValue;
+end;
+
 procedure TDemoNode.SetParent(const AValue: TDemoNode);
 begin
   if FParent=AValue then Exit;
@@ -1471,6 +1548,12 @@ begin
   end;
 end;
 
+procedure TDemoNode.SetActive(const AValue: boolean);
+begin
+  if FActive=AValue then Exit;
+  FActive:=AValue;
+end;
+
 procedure TDemoNode.SetStyleElements(const AValue: TCSSElement);
 begin
   if FStyleElements=AValue then Exit;
@@ -1701,16 +1784,12 @@ begin
   Result:=Attribute[Attr];
 end;
 
-function TDemoNode.HasCSSPseudo(const AttrID: TCSSNumericalID
-  ): boolean;
+function TDemoNode.HasCSSPseudoClass(const AttrID: TCSSNumericalID): boolean;
 begin
-  Result:=false;
-end;
-
-function TDemoNode.GetCSSPseudo(const AttrID: TCSSNumericalID
-  ): TCSSString;
-begin
-  Result:='';
+  if (AttrID>=DemoPseudoClassIDBase) and (AttrID<=DemoPseudoClassIDBase+ord(High(TDemoPseudoClass))) then
+    Result:=HasPseudoClass(TDemoPseudoClass(AttrID-DemoPseudoClassIDBase))
+  else
+    Result:=false;
 end;
 
 function TDemoNode.GetCSSEmpty: boolean;
@@ -1731,6 +1810,14 @@ begin
   end;
 end;
 
+function TDemoNode.HasPseudoClass(PseudoClass: TDemoPseudoClass): boolean;
+begin
+  case PseudoClass of
+    pcActive: Result:=Active;
+    pcHover: Result:=Hover;
+  end;
+end;
+
 function TDemoNode.GetCSSTypeName: TCSSString;
 begin
   Result:=CSSTypeName;
diff --git a/packages/fcl-css/tests/testcss.lpi b/packages/fcl-css/tests/testcss.lpi
index 5ef264d31a..f988ba558f 100644
--- a/packages/fcl-css/tests/testcss.lpi
+++ b/packages/fcl-css/tests/testcss.lpi
@@ -45,9 +45,6 @@
       <OtherUnitFiles Value="../src"/>
       <UnitOutputDirectory Value="lib/$(TargetCPU)-$(TargetOS)"/>
     </SearchPaths>
-    <Other>
-      <CustomOptions Value="-tunicodertl"/>
-    </Other>
   </CompilerOptions>
   <Debugging>
     <Exceptions>