diff --git a/Userland/Libraries/LibWeb/CSS/StyleValue.cpp b/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
index 7e339fc15e..3f2ac18ec0 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
@@ -150,6 +150,12 @@ LengthStyleValue const& StyleValue::as_length() const
     return static_cast<LengthStyleValue const&>(*this);
 }
 
+GridTrackSizeStyleValue const& StyleValue::as_grid_track_size() const
+{
+    VERIFY(is_grid_track_size());
+    return static_cast<GridTrackSizeStyleValue const&>(*this);
+}
+
 LinearGradientStyleValue const& StyleValue::as_linear_gradient() const
 {
     VERIFY(is_linear_gradient());
@@ -1198,6 +1204,25 @@ bool FrequencyStyleValue::equals(StyleValue const& other) const
     return m_frequency == other.as_frequency().m_frequency;
 }
 
+String GridTrackSizeStyleValue::to_string() const
+{
+    StringBuilder builder;
+    for (size_t i = 0; i < m_grid_track.size(); i++) {
+        builder.append(m_grid_track[i].to_string());
+        if (i != m_grid_track.size() - 1)
+            builder.append(" "sv);
+    }
+    return builder.to_string();
+}
+
+bool GridTrackSizeStyleValue::equals(StyleValue const& other) const
+{
+    if (type() != other.type())
+        return false;
+    auto const& typed_other = other.as_grid_track_size();
+    return m_grid_track == typed_other.grid_track_size();
+}
+
 String IdentifierStyleValue::to_string() const
 {
     return CSS::string_from_value_id(m_id);
@@ -1906,6 +1931,11 @@ NonnullRefPtr<ColorStyleValue> ColorStyleValue::create(Color color)
     return adopt_ref(*new ColorStyleValue(color));
 }
 
+NonnullRefPtr<GridTrackSizeStyleValue> GridTrackSizeStyleValue::create(Vector<CSS::GridTrackSize> grid_track_size)
+{
+    return adopt_ref(*new GridTrackSizeStyleValue(grid_track_size));
+}
+
 NonnullRefPtr<RectStyleValue> RectStyleValue::create(EdgeRect rect)
 {
     return adopt_ref(*new RectStyleValue(rect));
diff --git a/Userland/Libraries/LibWeb/CSS/StyleValue.h b/Userland/Libraries/LibWeb/CSS/StyleValue.h
index 0024d272ff..4e61321db2 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValue.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleValue.h
@@ -28,6 +28,7 @@
 #include <LibWeb/CSS/Display.h>
 #include <LibWeb/CSS/Enums.h>
 #include <LibWeb/CSS/Frequency.h>
+#include <LibWeb/CSS/GridTrackSize.h>
 #include <LibWeb/CSS/Length.h>
 #include <LibWeb/CSS/Number.h>
 #include <LibWeb/CSS/Parser/ComponentValue.h>
@@ -130,6 +131,7 @@ public:
         FlexFlow,
         Font,
         Frequency,
+        GridTrackSize,
         Identifier,
         Image,
         Inherit,
@@ -171,6 +173,7 @@ public:
     bool is_flex_flow() const { return type() == Type::FlexFlow; }
     bool is_font() const { return type() == Type::Font; }
     bool is_frequency() const { return type() == Type::Frequency; }
+    bool is_grid_track_size() const { return type() == Type::GridTrackSize; }
     bool is_identifier() const { return type() == Type::Identifier; }
     bool is_image() const { return type() == Type::Image; }
     bool is_inherit() const { return type() == Type::Inherit; }
@@ -210,6 +213,7 @@ public:
     FlexStyleValue const& as_flex() const;
     FontStyleValue const& as_font() const;
     FrequencyStyleValue const& as_frequency() const;
+    GridTrackSizeStyleValue const& as_grid_track_size() const;
     IdentifierStyleValue const& as_identifier() const;
     ImageStyleValue const& as_image() const;
     InheritStyleValue const& as_inherit() const;
@@ -247,6 +251,7 @@ public:
     FlexStyleValue& as_flex() { return const_cast<FlexStyleValue&>(const_cast<StyleValue const&>(*this).as_flex()); }
     FontStyleValue& as_font() { return const_cast<FontStyleValue&>(const_cast<StyleValue const&>(*this).as_font()); }
     FrequencyStyleValue& as_frequency() { return const_cast<FrequencyStyleValue&>(const_cast<StyleValue const&>(*this).as_frequency()); }
+    GridTrackSizeStyleValue& as_grid_track_size() { return const_cast<GridTrackSizeStyleValue&>(const_cast<StyleValue const&>(*this).as_grid_track_size()); }
     IdentifierStyleValue& as_identifier() { return const_cast<IdentifierStyleValue&>(const_cast<StyleValue const&>(*this).as_identifier()); }
     ImageStyleValue& as_image() { return const_cast<ImageStyleValue&>(const_cast<StyleValue const&>(*this).as_image()); }
     InheritStyleValue& as_inherit() { return const_cast<InheritStyleValue&>(const_cast<StyleValue const&>(*this).as_inherit()); }
@@ -897,6 +902,25 @@ private:
     Frequency m_frequency;
 };
 
+class GridTrackSizeStyleValue final : public StyleValue {
+public:
+    static NonnullRefPtr<GridTrackSizeStyleValue> create(Vector<CSS::GridTrackSize> grid_track_size);
+    virtual ~GridTrackSizeStyleValue() override = default;
+
+    Vector<CSS::GridTrackSize> grid_track_size() const { return m_grid_track; }
+    virtual String to_string() const override;
+    virtual bool equals(StyleValue const& other) const override;
+
+private:
+    explicit GridTrackSizeStyleValue(Vector<CSS::GridTrackSize> grid_track_size)
+        : StyleValue(Type::GridTrackSize)
+        , m_grid_track(grid_track_size)
+    {
+    }
+
+    Vector<CSS::GridTrackSize> m_grid_track;
+};
+
 class IdentifierStyleValue final : public StyleValue {
 public:
     static NonnullRefPtr<IdentifierStyleValue> create(CSS::ValueID id)
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index 0904e65f94..28f04dbd79 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -59,6 +59,7 @@ class FrequencyPercentage;
 class FrequencyStyleValue;
 class GridTrackPlacement;
 class GridTrackSize;
+class GridTrackSizeStyleValue;
 class IdentifierStyleValue;
 class ImageStyleValue;
 class InheritStyleValue;