diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index a27d131ff5d..5efc844bb1c 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -64,6 +64,7 @@ set(SOURCES
     CSS/Size.cpp
     CSS/StyleComputer.cpp
     CSS/StyleProperties.cpp
+    CSS/StyleProperty.cpp
     CSS/StyleSheet.cpp
     CSS/StyleSheetList.cpp
     CSS/StyleValue.cpp
diff --git a/Userland/Libraries/LibWeb/CSS/Length.cpp b/Userland/Libraries/LibWeb/CSS/Length.cpp
index 61637b4e662..509ad1ec0e3 100644
--- a/Userland/Libraries/LibWeb/CSS/Length.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Length.cpp
@@ -15,6 +15,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/BrowsingContext.h>
 #include <LibWeb/HTML/HTMLHtmlElement.h>
+#include <LibWeb/Layout/Node.h>
 
 namespace Web::CSS {
 
diff --git a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
index 02e065cd49d..ca0112ee5ff 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
@@ -54,6 +54,7 @@
 #include <LibWeb/DOM/Element.h>
 #include <LibWeb/FontCache.h>
 #include <LibWeb/HTML/HTMLHtmlElement.h>
+#include <LibWeb/Layout/Node.h>
 #include <LibWeb/Loader/ResourceLoader.h>
 #include <LibWeb/Platform/FontPlugin.h>
 #include <stdio.h>
diff --git a/Userland/Libraries/LibWeb/CSS/StyleProperty.cpp b/Userland/Libraries/LibWeb/CSS/StyleProperty.cpp
new file mode 100644
index 00000000000..736007f01b3
--- /dev/null
+++ b/Userland/Libraries/LibWeb/CSS/StyleProperty.cpp
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2023, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/CSS/StyleProperty.h>
+#include <LibWeb/CSS/StyleValue.h>
+
+namespace Web::CSS {
+
+StyleProperty::~StyleProperty() = default;
+
+}
diff --git a/Userland/Libraries/LibWeb/CSS/StyleProperty.h b/Userland/Libraries/LibWeb/CSS/StyleProperty.h
index 8adfc386f03..83723251041 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleProperty.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleProperty.h
@@ -6,6 +6,9 @@
 
 #pragma once
 
+#include <AK/DeprecatedString.h>
+#include <LibWeb/CSS/PropertyID.h>
+
 namespace Web::CSS {
 
 enum class Important {
@@ -14,6 +17,8 @@ enum class Important {
 };
 
 struct StyleProperty {
+    ~StyleProperty();
+
     Important important { Important::No };
     CSS::PropertyID property_id;
     NonnullRefPtr<StyleValue const> value;
diff --git a/Userland/Libraries/LibWeb/CSS/StyleValues/ImageStyleValue.cpp b/Userland/Libraries/LibWeb/CSS/StyleValues/ImageStyleValue.cpp
index 0039031c0a0..77f20c19c30 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValues/ImageStyleValue.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleValues/ImageStyleValue.cpp
@@ -8,9 +8,11 @@
  */
 
 #include "ImageStyleValue.h"
+#include <LibWeb/CSS/ComputedValues.h>
 #include <LibWeb/CSS/Serialize.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/Loader/ResourceLoader.h>
+#include <LibWeb/Painting/PaintContext.h>
 #include <LibWeb/Platform/Timer.h>
 
 namespace Web::CSS {
diff --git a/Userland/Libraries/LibWeb/DOM/Element.cpp b/Userland/Libraries/LibWeb/DOM/Element.cpp
index 3cdaca22f93..5a032c3ce07 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Element.cpp
@@ -1703,4 +1703,9 @@ size_t Element::attribute_list_size() const
     return m_attributes->length();
 }
 
+void Element::set_computed_css_values(RefPtr<CSS::StyleProperties> style)
+{
+    m_computed_css_values = move(style);
+}
+
 }
diff --git a/Userland/Libraries/LibWeb/DOM/Element.h b/Userland/Libraries/LibWeb/DOM/Element.h
index 86fe0fc816d..b34efa081ef 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.h
+++ b/Userland/Libraries/LibWeb/DOM/Element.h
@@ -21,7 +21,6 @@
 #include <LibWeb/HTML/EventLoop/Task.h>
 #include <LibWeb/HTML/ScrollOptions.h>
 #include <LibWeb/HTML/TagNames.h>
-#include <LibWeb/Layout/Node.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::DOM {
@@ -137,7 +136,7 @@ public:
 
     CSS::StyleProperties* computed_css_values() { return m_computed_css_values.ptr(); }
     CSS::StyleProperties const* computed_css_values() const { return m_computed_css_values.ptr(); }
-    void set_computed_css_values(RefPtr<CSS::StyleProperties> style) { m_computed_css_values = move(style); }
+    void set_computed_css_values(RefPtr<CSS::StyleProperties>);
     NonnullRefPtr<CSS::StyleProperties> resolved_css_values();
 
     CSS::CSSStyleDeclaration const* inline_style() const;
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index e5bf9e62da5..8cec154ee1c 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -163,6 +163,8 @@ class URLStyleValue;
 enum class MediaFeatureID;
 enum class PropertyID;
 enum class ValueID;
+
+struct BackgroundLayerData;
 }
 
 namespace Web::CSS::Parser {
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLBlinkElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLBlinkElement.cpp
index 6bfa7806fd8..011d5763640 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLBlinkElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLBlinkElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/HTML/HTMLBlinkElement.h>
+#include <LibWeb/Layout/Node.h>
 #include <LibWeb/Platform/Timer.h>
 
 namespace Web::HTML {
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLBodyElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLBodyElement.cpp
index af3878235f9..e206ee08fe8 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLBodyElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLBodyElement.cpp
@@ -10,6 +10,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/HTMLBodyElement.h>
 #include <LibWeb/HTML/Window.h>
+#include <LibWeb/Layout/Node.h>
 
 namespace Web::HTML {
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLHeadingElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLHeadingElement.cpp
index ce132ae7c9e..f7577cd74db 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLHeadingElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLHeadingElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/IdentifierStyleValue.h>
 #include <LibWeb/HTML/HTMLHeadingElement.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLHtmlElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLHtmlElement.cpp
index 606519ac026..db4ef5ecc2e 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLHtmlElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLHtmlElement.cpp
@@ -6,6 +6,7 @@
 
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/HTML/HTMLHtmlElement.h>
+#include <LibWeb/Layout/Node.h>
 
 namespace Web::HTML {
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLMarqueeElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLMarqueeElement.cpp
index 6c7ff94696a..573bf8b6371 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLMarqueeElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLMarqueeElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/ColorStyleValue.h>
 #include <LibWeb/HTML/HTMLMarqueeElement.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLMediaElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLMediaElement.cpp
index fd9a4cf34db..635de9e564a 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLMediaElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLMediaElement.cpp
@@ -28,6 +28,7 @@
 #include <LibWeb/HTML/TrackEvent.h>
 #include <LibWeb/HTML/VideoTrack.h>
 #include <LibWeb/HTML/VideoTrackList.h>
+#include <LibWeb/Layout/Node.h>
 #include <LibWeb/MimeSniff/MimeType.h>
 #include <LibWeb/WebIDL/Promise.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLParagraphElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLParagraphElement.cpp
index 3c1e3ae52af..554938b888f 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLParagraphElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLParagraphElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/IdentifierStyleValue.h>
 #include <LibWeb/HTML/HTMLParagraphElement.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLPreElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLPreElement.cpp
index 89770cb3bdf..7adea79fae3 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLPreElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLPreElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/IdentifierStyleValue.h>
 #include <LibWeb/HTML/HTMLPreElement.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLTableCaptionElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLTableCaptionElement.cpp
index 022e22089af..555b7108b9c 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLTableCaptionElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLTableCaptionElement.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/IdentifierStyleValue.h>
 #include <LibWeb/HTML/HTMLTableCaptionElement.h>
 
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
index bf7529034e2..762843569f4 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
@@ -6,6 +6,7 @@
 
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/CSS/Parser/Parser.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/ColorStyleValue.h>
 #include <LibWeb/CSS/StyleValues/IdentifierStyleValue.h>
 #include <LibWeb/HTML/HTMLTableCellElement.h>
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
index f26458ccfc9..8f8a3281c30 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
@@ -7,6 +7,7 @@
 
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/CSS/Parser/Parser.h>
+#include <LibWeb/CSS/StyleProperties.h>
 #include <LibWeb/CSS/StyleValues/ColorStyleValue.h>
 #include <LibWeb/DOM/ElementFactory.h>
 #include <LibWeb/DOM/HTMLCollection.h>
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLVideoElement.h b/Userland/Libraries/LibWeb/HTML/HTMLVideoElement.h
index 1c2d3e59e19..3b06af60015 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLVideoElement.h
+++ b/Userland/Libraries/LibWeb/HTML/HTMLVideoElement.h
@@ -8,9 +8,11 @@
 
 #include <AK/Optional.h>
 #include <LibGfx/Forward.h>
+#include <LibGfx/Rect.h>
 #include <LibWeb/DOM/DocumentLoadEventDelayer.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/HTMLMediaElement.h>
+#include <LibWeb/PixelUnits.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::HTML {
diff --git a/Userland/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.cpp b/Userland/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.cpp
index f661ee6f808..aa6681f575d 100644
--- a/Userland/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.cpp
@@ -7,6 +7,7 @@
 
 #include <AK/CharacterTypes.h>
 #include <AK/Debug.h>
+#include <AK/GenericShorthands.h>
 #include <AK/SourceLocation.h>
 #include <LibTextCodec/Decoder.h>
 #include <LibWeb/HTML/Parser/Entities.h>
diff --git a/Userland/Libraries/LibWeb/SVG/SVGGraphicsElement.h b/Userland/Libraries/LibWeb/SVG/SVGGraphicsElement.h
index 3bcb380ec7d..1016ee8dc19 100644
--- a/Userland/Libraries/LibWeb/SVG/SVGGraphicsElement.h
+++ b/Userland/Libraries/LibWeb/SVG/SVGGraphicsElement.h
@@ -8,6 +8,7 @@
 #pragma once
 
 #include <LibGfx/PaintStyle.h>
+#include <LibGfx/Painter.h>
 #include <LibGfx/Path.h>
 #include <LibWeb/DOM/Node.h>
 #include <LibWeb/SVG/AttributeParser.h>
diff --git a/Userland/Libraries/LibWeb/SVG/SVGStopElement.h b/Userland/Libraries/LibWeb/SVG/SVGStopElement.h
index a1167397b5e..49b2cb20d6c 100644
--- a/Userland/Libraries/LibWeb/SVG/SVGStopElement.h
+++ b/Userland/Libraries/LibWeb/SVG/SVGStopElement.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibGfx/Color.h>
 #include <LibWeb/SVG/AttributeParser.h>
 #include <LibWeb/SVG/SVGAnimatedNumber.h>
 #include <LibWeb/SVG/SVGElement.h>
diff --git a/Userland/Libraries/LibWeb/WebGL/WebGLRenderingContextBase.cpp b/Userland/Libraries/LibWeb/WebGL/WebGLRenderingContextBase.cpp
index b501b04084d..e01a21ef31a 100644
--- a/Userland/Libraries/LibWeb/WebGL/WebGLRenderingContextBase.cpp
+++ b/Userland/Libraries/LibWeb/WebGL/WebGLRenderingContextBase.cpp
@@ -7,6 +7,7 @@
 #include <AK/Debug.h>
 #include <LibGL/GLContext.h>
 #include <LibWeb/HTML/HTMLCanvasElement.h>
+#include <LibWeb/Layout/Node.h>
 #include <LibWeb/WebGL/WebGLRenderingContextBase.h>
 
 namespace Web::WebGL {