diff --git a/Libraries/LibHTML/CSS/StyleProperties.cpp b/Libraries/LibHTML/CSS/StyleProperties.cpp
index e0386e63b0..ff3528f7d7 100644
--- a/Libraries/LibHTML/CSS/StyleProperties.cpp
+++ b/Libraries/LibHTML/CSS/StyleProperties.cpp
@@ -97,3 +97,23 @@ int StyleProperties::line_height() const
     // FIXME: Allow overriding the line-height. We currently default to 140% which seems to look nice.
     return (int)(font().glyph_height() * 1.4f);
 }
+
+bool StyleProperties::operator==(const StyleProperties& other) const
+{
+    if (m_property_values.size() != other.m_property_values.size())
+        return false;
+
+    for (auto& it : m_property_values) {
+        auto jt = other.m_property_values.find(it.key);
+        if (jt == other.m_property_values.end())
+            return false;
+        auto& my_value = *it.value;
+        auto& other_value = *jt->value;
+        if (my_value.type() != other_value.type())
+            return false;
+        if (my_value.to_string() != other_value.to_string())
+            return false;
+    }
+
+    return true;
+}
diff --git a/Libraries/LibHTML/CSS/StyleProperties.h b/Libraries/LibHTML/CSS/StyleProperties.h
index c18b87ef93..4f0221bd39 100644
--- a/Libraries/LibHTML/CSS/StyleProperties.h
+++ b/Libraries/LibHTML/CSS/StyleProperties.h
@@ -34,6 +34,9 @@ public:
 
     int line_height() const;
 
+    bool operator==(const StyleProperties&) const;
+    bool operator!=(const StyleProperties& other) const { return !(*this == other); }
+
 private:
     HashMap<unsigned, NonnullRefPtr<StyleValue>> m_property_values;
 
diff --git a/Libraries/LibHTML/DOM/Document.cpp b/Libraries/LibHTML/DOM/Document.cpp
index 48bbeec6e5..cd3c97715b 100644
--- a/Libraries/LibHTML/DOM/Document.cpp
+++ b/Libraries/LibHTML/DOM/Document.cpp
@@ -201,7 +201,12 @@ void Document::set_hovered_node(Node* node)
     if (m_hovered_node == node)
         return;
 
+    RefPtr<Node> old_hovered_node = move(m_hovered_node);
     m_hovered_node = node;
-    update_style();
+
+    if (old_hovered_node)
+        old_hovered_node->invalidate_style();
+    if (m_hovered_node)
+        m_hovered_node->invalidate_style();
 }
 
diff --git a/Libraries/LibHTML/DOM/Element.cpp b/Libraries/LibHTML/DOM/Element.cpp
index 2627e628f8..67b00abcb1 100644
--- a/Libraries/LibHTML/DOM/Element.cpp
+++ b/Libraries/LibHTML/DOM/Element.cpp
@@ -1,4 +1,5 @@
 #include <LibHTML/CSS/StyleResolver.h>
+#include <LibHTML/DOM/Document.h>
 #include <LibHTML/DOM/Element.h>
 #include <LibHTML/Layout/LayoutBlock.h>
 #include <LibHTML/Layout/LayoutInline.h>
@@ -92,3 +93,48 @@ RefPtr<LayoutNode> Element::create_layout_node(const StyleResolver& resolver, co
 void Element::parse_attribute(const String&, const String&)
 {
 }
+
+enum class StyleDifference {
+    None,
+    NeedsRepaint,
+    NeedsRelayout,
+};
+
+static StyleDifference compute_style_difference(const StyleProperties& old_style, const StyleProperties& new_style, const Document& document)
+{
+    if (old_style == new_style)
+        return StyleDifference::None;
+
+    bool needs_repaint = false;
+    bool needs_relayout = false;
+
+    if (new_style.color_or_fallback(CSS::PropertyID::Color, document, Color::Black) != old_style.color_or_fallback(CSS::PropertyID::Color, document, Color::Black))
+        needs_repaint = true;
+    else if (new_style.color_or_fallback(CSS::PropertyID::BackgroundColor, document, Color::Black) != old_style.color_or_fallback(CSS::PropertyID::BackgroundColor, document, Color::Black))
+        needs_repaint = true;
+
+    if (needs_relayout)
+        return StyleDifference::NeedsRelayout;
+    if (needs_repaint)
+        return StyleDifference::NeedsRepaint;
+    return StyleDifference::None;
+}
+
+void Element::recompute_style()
+{
+    ASSERT(parent());
+    auto* parent_layout_node = parent()->layout_node();
+    ASSERT(parent_layout_node);
+    auto style = document().style_resolver().resolve_style(*this, &parent_layout_node->style());
+    ASSERT(layout_node());
+    auto diff = compute_style_difference(layout_node()->style(), *style, document());
+    if (diff == StyleDifference::None)
+        return;
+    layout_node()->set_style(*style);
+    if (diff == StyleDifference::NeedsRelayout) {
+        ASSERT_NOT_REACHED();
+    }
+    if (diff == StyleDifference::NeedsRepaint) {
+        layout_node()->set_needs_display();
+    }
+}
diff --git a/Libraries/LibHTML/DOM/Element.h b/Libraries/LibHTML/DOM/Element.h
index db3e260ed8..1c354a6af0 100644
--- a/Libraries/LibHTML/DOM/Element.h
+++ b/Libraries/LibHTML/DOM/Element.h
@@ -2,6 +2,9 @@
 
 #include <AK/String.h>
 #include <LibHTML/DOM/ParentNode.h>
+#include <LibHTML/Layout/LayoutNode.h>
+
+class LayoutNodeWithStyle;
 
 class Attribute {
 public:
@@ -45,6 +48,11 @@ public:
     virtual void apply_presentational_hints(StyleProperties&) const {}
     virtual void parse_attribute(const String& name, const String& value);
 
+    void recompute_style();
+
+    LayoutNodeWithStyle* layout_node() { return static_cast<LayoutNodeWithStyle*>(Node::layout_node()); }
+    const LayoutNodeWithStyle* layout_node() const { return static_cast<const LayoutNodeWithStyle*>(Node::layout_node()); }
+
 private:
     RefPtr<LayoutNode> create_layout_node(const StyleResolver&, const StyleProperties* parent_style) const override;
 
diff --git a/Libraries/LibHTML/DOM/Node.cpp b/Libraries/LibHTML/DOM/Node.cpp
index 14c7a38a29..54857808eb 100644
--- a/Libraries/LibHTML/DOM/Node.cpp
+++ b/Libraries/LibHTML/DOM/Node.cpp
@@ -102,3 +102,11 @@ RefPtr<LayoutNode> Node::create_layout_node(const StyleResolver&, const StylePro
 {
     return nullptr;
 }
+
+void Node::invalidate_style()
+{
+    for (auto* node = this; node; node = node->parent()) {
+        if (is<Element>(*node))
+            to<Element>(*node).recompute_style();
+    }
+}
diff --git a/Libraries/LibHTML/DOM/Node.h b/Libraries/LibHTML/DOM/Node.h
index 9efd4bf962..1154d0466d 100644
--- a/Libraries/LibHTML/DOM/Node.h
+++ b/Libraries/LibHTML/DOM/Node.h
@@ -71,6 +71,8 @@ public:
 
     virtual bool is_child_allowed(const Node&) const { return true; }
 
+    void invalidate_style();
+
 protected:
     Node(Document&, NodeType);
 
diff --git a/Libraries/LibHTML/Layout/LayoutNode.h b/Libraries/LibHTML/Layout/LayoutNode.h
index b412e59370..19c4c50127 100644
--- a/Libraries/LibHTML/Layout/LayoutNode.h
+++ b/Libraries/LibHTML/Layout/LayoutNode.h
@@ -111,6 +111,7 @@ public:
     virtual ~LayoutNodeWithStyle() override {}
 
     const StyleProperties& style() const { return m_style; }
+    void set_style(const StyleProperties& style) { m_style = style; }
 
 protected:
     explicit LayoutNodeWithStyle(const Node* node, NonnullRefPtr<StyleProperties> style)