diff --git a/src/AngleSharp.Css/Values/Composites/CssBackgroundLayerValue.cs b/src/AngleSharp.Css/Values/Composites/CssBackgroundLayerValue.cs
index 699deb6..2b4aa78 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBackgroundLayerValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBackgroundLayerValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     sealed class CssBackgroundLayerValue : ICssCompositeValue, IEquatable<CssBackgroundLayerValue>
     {
@@ -139,11 +140,17 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssBackgroundLayerValue other)
         {
-            return _clip.Equals(other._clip) &&
-                _repeat.Equals(other._repeat) &&
-                _attachment.Equals(other._attachment) &&
-                _origin.Equals(other._origin) &&
-                _size.Equals(other._size);
+            if(other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_clip, other._clip) &&
+                       comparer.Equals(_repeat, other._repeat) &&
+                       comparer.Equals(_attachment, other._attachment) &&
+                       comparer.Equals(_origin, other._origin) &&
+                       comparer.Equals(_size, other._size);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBackgroundLayerValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssBackgroundSizeValue.cs b/src/AngleSharp.Css/Values/Composites/CssBackgroundSizeValue.cs
index 2a214c0..00b0a21 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBackgroundSizeValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBackgroundSizeValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS background size definition.
@@ -94,7 +95,16 @@ public String CssText
         /// </summary>
         /// <param name="other">The other background size.</param>
         /// <returns>True if both are equivalent, otherwise false.</returns>
-        public Boolean Equals(CssBackgroundSizeValue other) => _mode == other._mode && _height.Equals(other._height) && _width.Equals(other._width);
+        public Boolean Equals(CssBackgroundSizeValue other)
+        {
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return _mode == other._mode && comparer.Equals(_height, other._height) && comparer.Equals(_width, other._width);
+            }
+
+            return false;
+        }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBackgroundSizeValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Composites/CssBackgroundValue.cs b/src/AngleSharp.Css/Values/Composites/CssBackgroundValue.cs
index 3410371..237b451 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBackgroundValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBackgroundValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS background definition.
@@ -78,7 +79,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssBackgroundValue other)
         {
-            return _color.Equals(other._color) && _layers.Equals(other._layers);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_color, other._color) && comparer.Equals(_layers, other._layers);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBackgroundValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssBorderImageSliceValue.cs b/src/AngleSharp.Css/Values/Composites/CssBorderImageSliceValue.cs
index ad1316a..7089e80 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBorderImageSliceValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBorderImageSliceValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the CSS border image slice definition.
@@ -124,7 +125,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssBorderImageSliceValue other)
         {
-            return _filled == other._filled && _bottom.Equals(other._bottom) && _left.Equals(other._left) && _right.Equals(other._right) && _top.Equals(other._top);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return _filled == other._filled && comparer.Equals(_bottom, other._bottom) && comparer.Equals(_left, other._left) && comparer.Equals(_right, other._right) && comparer.Equals(_top, other._top);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBorderImageSliceValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssBorderImageValue.cs b/src/AngleSharp.Css/Values/Composites/CssBorderImageValue.cs
index b07f59f..2de35bb 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBorderImageValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBorderImageValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS border image definition.
@@ -111,7 +112,7 @@ public String CssText
 
         #endregion
 
-        #region
+        #region Methods
 
         /// <summary>
         /// Checks if the current value is equal to the provided one.
@@ -120,11 +121,17 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssBorderImageValue other)
         {
-            return _image.Equals(other._image) &&
-                _slice.Equals(other._slice) &&
-                _widths.Equals(other._widths) &&
-                _outsets.Equals(other._outsets) &&
-                _repeat.Equals(other._repeat);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_image, other._image) &&
+                    comparer.Equals(_slice, other._slice) &&
+                    comparer.Equals(_widths, other._widths) &&
+                    comparer.Equals(_outsets, other._outsets) &&
+                    comparer.Equals(_repeat, other._repeat);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBorderImageValue value && Equals(value);
@@ -137,7 +144,7 @@ ICssValue ICssValue.Compute(ICssComputeContext context)
             var offsets = _outsets.Compute(context);
             var repeat = _repeat.Compute(context);
             return new CssBorderImageValue(image, slice, widths, offsets, repeat);
-    }
+        }
 
         #endregion
     }
diff --git a/src/AngleSharp.Css/Values/Composites/CssBorderRadiusValue.cs b/src/AngleSharp.Css/Values/Composites/CssBorderRadiusValue.cs
index 54f2b18..c82f32d 100644
--- a/src/AngleSharp.Css/Values/Composites/CssBorderRadiusValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssBorderRadiusValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a border radius value.
@@ -74,7 +75,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssBorderRadiusValue other)
         {
-            return _horizontal.Equals(other._horizontal) && _vertical.Equals(other._vertical);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_horizontal, other._horizontal) && comparer.Equals(_vertical, other._vertical);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssBorderRadiusValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssCursorValue.cs b/src/AngleSharp.Css/Values/Composites/CssCursorValue.cs
index 7044b15..c46e660 100644
--- a/src/AngleSharp.Css/Values/Composites/CssCursorValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssCursorValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
     using System.Linq;
 
     /// <summary>
@@ -74,22 +75,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssCursorValue other)
         {
-            var l = _definitions.Length;
-
-            if (_cursor.Equals(other._cursor) && l == other._definitions.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < l; i++)
-                {
-                    var a = _definitions[i];
-                    var b = other._definitions[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var l = _definitions.Length;
 
-                    if (!a.Equals(b))
+                if (comparer.Equals(_cursor, other._cursor) && l == other._definitions.Length)
+                {
+                    for (var i = 0; i < l; i++)
                     {
-                        return false;
+                        var a = _definitions[i];
+                        var b = other._definitions[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Composites/CssCustomCursorValue.cs b/src/AngleSharp.Css/Values/Composites/CssCustomCursorValue.cs
index fd23ab0..cef5b3d 100644
--- a/src/AngleSharp.Css/Values/Composites/CssCustomCursorValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssCustomCursorValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     sealed class CssCustomCursorValue : ICssCompositeValue, IEquatable<CssCustomCursorValue>
     {
@@ -72,7 +73,14 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssCustomCursorValue other)
         {
-            return _position.Equals(other._position) && _source.Equals(other._source);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_position, other._position) &&
+                    comparer.Equals(_source, other._source);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssCustomCursorValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssFontValue.cs b/src/AngleSharp.Css/Values/Composites/CssFontValue.cs
index 607ecc1..9307a4e 100644
--- a/src/AngleSharp.Css/Values/Composites/CssFontValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssFontValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS font definition.
@@ -145,13 +146,19 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssFontValue other)
         {
-            return _lineHeight.Equals(other._lineHeight) &&
-                _size.Equals(other._size) &&
-                _weight.Equals(other._weight) &&
-                _stretch.Equals(other._stretch) &&
-                _variant.Equals(other._variant) &&
-                _style.Equals(other._style) &&
-                _fontFamilies.Equals(other._fontFamilies);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_lineHeight, other._lineHeight) &&
+                    comparer.Equals(_size, other._size) &&
+                    comparer.Equals(_weight, other._weight) &&
+                    comparer.Equals(_stretch, other._stretch) &&
+                    comparer.Equals(_variant, other._variant) &&
+                    comparer.Equals(_style, other._style) &&
+                    comparer.Equals(_fontFamilies, other._fontFamilies);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssFontValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssGradientStopValue.cs b/src/AngleSharp.Css/Values/Composites/CssGradientStopValue.cs
index a3e57a2..390205f 100644
--- a/src/AngleSharp.Css/Values/Composites/CssGradientStopValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssGradientStopValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// More information can be found at the W3C:
@@ -69,7 +70,13 @@ public CssGradientStopValue(CssColorValue color, ICssValue location = null)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssGradientStopValue other)
         {
-            return _color.Equals(other._color) && _location.Equals(other._location);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_color, other._color) && comparer.Equals(_location, other._location);
+            }
+
+            return false;
         }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
diff --git a/src/AngleSharp.Css/Values/Composites/CssGridTemplateValue.cs b/src/AngleSharp.Css/Values/Composites/CssGridTemplateValue.cs
index 154011e..3c2f50f 100644
--- a/src/AngleSharp.Css/Values/Composites/CssGridTemplateValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssGridTemplateValue.cs
@@ -114,7 +114,15 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssGridTemplateValue other)
         {
-            return _areas.Equals(other._areas) && _columns.Equals(other._columns) && _rows.Equals(other._rows);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_areas, other._areas) &&
+                    comparer.Equals(_columns, other._columns) &&
+                    comparer.Equals(_rows, other._rows);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssGridTemplateValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssGridValue.cs b/src/AngleSharp.Css/Values/Composites/CssGridValue.cs
index 369d919..3fda365 100644
--- a/src/AngleSharp.Css/Values/Composites/CssGridValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssGridValue.cs
@@ -99,24 +99,28 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssGridValue other)
         {
-            if (_rows.Equals(other._rows) && _columns.Equals(other._columns) && _dense == other._dense)
+            if (other is not null)
             {
-                var l = _sizes.Length;
-
-                if (l == other._sizes.Length)
+                var comparer = EqualityComparer<ICssValue>.Default;
+                if (comparer.Equals(_rows, other._rows) && comparer.Equals(_columns, other._columns) && _dense == other._dense)
                 {
-                    for (var i = 0; i < l; i++)
-                    {
-                        var a = _sizes[i];
-                        var b = other._sizes[i];
+                    var l = _sizes.Length;
 
-                        if (!a.Equals(b))
+                    if (l == other._sizes.Length)
+                    {
+                        for (var i = 0; i < l; i++)
                         {
-                            return false;
+                            var a = _sizes[i];
+                            var b = other._sizes[i];
+
+                            if (!comparer.Equals(a, b))
+                            {
+                                return false;
+                            }
                         }
-                    }
 
-                    return true;
+                        return true;
+                    }
                 }
             }
 
diff --git a/src/AngleSharp.Css/Values/Composites/CssImageRepeatsValue.cs b/src/AngleSharp.Css/Values/Composites/CssImageRepeatsValue.cs
index ca5cfbd..44070d2 100644
--- a/src/AngleSharp.Css/Values/Composites/CssImageRepeatsValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssImageRepeatsValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS image repeat definition.
@@ -81,7 +82,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssImageRepeatsValue other)
         {
-            return _horizontal.Equals(other._horizontal) && _vertical.Equals(other._vertical);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_horizontal, other._horizontal) && comparer.Equals(_vertical, other._vertical);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssImageRepeatsValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Composites/CssPoint2D.cs b/src/AngleSharp.Css/Values/Composites/CssPoint2D.cs
index 42eb945..59decaf 100644
--- a/src/AngleSharp.Css/Values/Composites/CssPoint2D.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssPoint2D.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a point value consisting of two distances.
@@ -154,7 +155,8 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssPoint2D other)
         {
-            return _x.Equals(other._x) && _y.Equals(other._y);
+            var comparer = EqualityComparer<ICssValue>.Default;
+            return comparer.Equals(_x, other._x) && comparer.Equals(_y, other._y);
         }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
diff --git a/src/AngleSharp.Css/Values/Composites/CssRatioValue.cs b/src/AngleSharp.Css/Values/Composites/CssRatioValue.cs
index a68e353..205aca8 100644
--- a/src/AngleSharp.Css/Values/Composites/CssRatioValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssRatioValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a ratio (top to bottom) value.
@@ -58,7 +59,8 @@ public CssRatioValue(ICssValue top, ICssValue bottom)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssRatioValue other)
         {
-            return _top.Equals(other._top) && _bottom.Equals(other._bottom);
+            var comparer = EqualityComparer<ICssValue>.Default;
+            return comparer.Equals(_top, other._top) && comparer.Equals(_bottom, other._bottom);
         }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
diff --git a/src/AngleSharp.Css/Values/Composites/CssShadowValue.cs b/src/AngleSharp.Css/Values/Composites/CssShadowValue.cs
index 6d5d9f6..d7b27c0 100644
--- a/src/AngleSharp.Css/Values/Composites/CssShadowValue.cs
+++ b/src/AngleSharp.Css/Values/Composites/CssShadowValue.cs
@@ -44,7 +44,7 @@ public CssShadowValue(Boolean inset, ICssValue offsetX, ICssValue offsetY, ICssV
         #endregion
 
         #region Properties
-        
+
         /// <summary>
         /// Gets the CSS text representation.
         /// </summary>
@@ -122,12 +122,18 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssShadowValue other)
         {
-            return _blurRadius.Equals(other._blurRadius) &&
-                _spreadRadius.Equals(other._spreadRadius) &&
-                _color.Equals(other._color) &&
-                _inset == other._inset &&
-                _offsetX.Equals(other._offsetX) &&
-                _offsetY.Equals(other._offsetY);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_blurRadius, other._blurRadius) &&
+                       comparer.Equals(_spreadRadius, other._spreadRadius) &&
+                       comparer.Equals(_color, other._color) &&
+                       _inset == other._inset &&
+                       comparer.Equals(_offsetX, other._offsetX) &&
+                       comparer.Equals(_offsetY, other._offsetY);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssShadowValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/CssChildValue.cs b/src/AngleSharp.Css/Values/CssChildValue.cs
index aad3bc6..df579fa 100644
--- a/src/AngleSharp.Css/Values/CssChildValue.cs
+++ b/src/AngleSharp.Css/Values/CssChildValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS value that was born from a shorthand.
@@ -58,7 +59,13 @@ public CssChildValue(ICssValue parent, ICssValue value = null)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssChildValue other)
         {
-            return _parent.Equals(other._parent) && _value.Equals(other._value);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_parent, other._parent) && comparer.Equals(_value, other._value);
+            }
+
+            return false;
         }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
diff --git a/src/AngleSharp.Css/Values/Functions/CssAttrValue.cs b/src/AngleSharp.Css/Values/Functions/CssAttrValue.cs
index 522d1cf..33fd2e7 100644
--- a/src/AngleSharp.Css/Values/Functions/CssAttrValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssAttrValue.cs
@@ -59,10 +59,7 @@ public CssAttrValue(String attribute)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssAttrValue other)
-        {
-            return _attribute.Equals(other._attribute);
-        }
+        public Boolean Equals(CssAttrValue other) => other is not null && _attribute == other._attribute;
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssAttrValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssConicGradientValue.cs b/src/AngleSharp.Css/Values/Functions/CssConicGradientValue.cs
index 2497ec6..80900a7 100644
--- a/src/AngleSharp.Css/Values/Functions/CssConicGradientValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssConicGradientValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
     using System.Linq;
 
     /// <summary>
@@ -131,22 +132,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssConicGradientValue other)
         {
-            var l = _stops.Length;
-
-            if (_angle.Equals(other._angle) && _center.Equals(other._center) && _repeating == other._repeating && l == other._stops.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < l; i++)
-                {
-                    var a = _stops[i];
-                    var b = other._stops[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var l = _stops.Length;
 
-                    if (!a.Equals(b))
+                if (comparer.Equals(_angle, other._angle) && comparer.Equals(_center, other._center) && _repeating == other._repeating && l == other._stops.Length)
+                {
+                    for (var i = 0; i < l; i++)
                     {
-                        return false;
+                        var a = _stops[i];
+                        var b = other._stops[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Functions/CssContentValue.cs b/src/AngleSharp.Css/Values/Functions/CssContentValue.cs
index 463e11d..6901d50 100644
--- a/src/AngleSharp.Css/Values/Functions/CssContentValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssContentValue.cs
@@ -59,7 +59,15 @@ public CssContentValue(String type)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssContentValue other) => _type.Equals(other._type);
+        public Boolean Equals(CssContentValue other)
+        {
+            if (other is not null)
+            {
+                return _type == other._type;
+            }
+
+            return false;
+        }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssContentValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssCubicBezierValue.cs b/src/AngleSharp.Css/Values/Functions/CssCubicBezierValue.cs
index 8c698af..1ba759e 100644
--- a/src/AngleSharp.Css/Values/Functions/CssCubicBezierValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssCubicBezierValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a cubic-bezier timing-function object.
@@ -159,8 +160,16 @@ public String CssText
         /// </summary>
         /// <param name="other">The cubic bezier to compare to.</param>
         /// <returns>True if both have the same parameters, otherwise false.</returns>
-        public Boolean Equals(CssCubicBezierValue other) =>
-            _x1.Equals(other._x1) && _x2.Equals(other._x2) && _y1.Equals(other._y1) && _y2.Equals(other._y2);
+        public Boolean Equals(CssCubicBezierValue other)
+        {
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_x1, other._x1) && comparer.Equals(_x2, other._x2) && comparer.Equals(_y1, other._y1) && comparer.Equals(_y2, other._y2);
+            }
+
+            return false;
+        }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
         {
diff --git a/src/AngleSharp.Css/Values/Functions/CssFitContentValue.cs b/src/AngleSharp.Css/Values/Functions/CssFitContentValue.cs
index 81b769e..b5e1d96 100644
--- a/src/AngleSharp.Css/Values/Functions/CssFitContentValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssFitContentValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS fit-content function call.
@@ -59,7 +60,16 @@ public CssFitContentValue(ICssValue dim)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssFitContentValue other) => _dim.Equals(other._dim);
+        public Boolean Equals(CssFitContentValue other)
+        {
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_dim, other._dim);
+            }
+
+            return false;
+        }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssFitContentValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssFontFormatValue.cs b/src/AngleSharp.Css/Values/Functions/CssFontFormatValue.cs
index d62946a..4e2c224 100644
--- a/src/AngleSharp.Css/Values/Functions/CssFontFormatValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssFontFormatValue.cs
@@ -39,7 +39,7 @@ public CssFontFormatValue(String fontFormat)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssFontFormatValue other) => _fontFormat.Equals(other._fontFormat);
+        public Boolean Equals(CssFontFormatValue other) => other is not null && _fontFormat == other._fontFormat;
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssFontFormatValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssLinearGradientValue.cs b/src/AngleSharp.Css/Values/Functions/CssLinearGradientValue.cs
index 6a1d470..b682266 100644
--- a/src/AngleSharp.Css/Values/Functions/CssLinearGradientValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssLinearGradientValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
     using System.Linq;
 
     /// <summary>
@@ -123,22 +124,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssLinearGradientValue other)
         {
-            var l = _stops.Length;
-
-            if (_angle.Equals(other._angle) && _repeating == other._repeating && l == other._stops.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < l; i++)
-                {
-                    var a = _stops[i];
-                    var b = other._stops[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var l = _stops.Length;
 
-                    if (!a.Equals(b))
+                if (comparer.Equals(_angle, other._angle) && _repeating == other._repeating && l == other._stops.Length)
+                {
+                    for (var i = 0; i < l; i++)
                     {
-                        return false;
+                        var a = _stops[i];
+                        var b = other._stops[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Functions/CssLocalFontValue.cs b/src/AngleSharp.Css/Values/Functions/CssLocalFontValue.cs
index 38cc33b..f6bdd1d 100644
--- a/src/AngleSharp.Css/Values/Functions/CssLocalFontValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssLocalFontValue.cs
@@ -39,7 +39,7 @@ public CssLocalFontValue(String fontName)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssLocalFontValue other) => _fontName.Equals(other._fontName);
+        public Boolean Equals(CssLocalFontValue other) => other is not null && _fontName == other._fontName;
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssLocalFontValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssMatrixValue.cs b/src/AngleSharp.Css/Values/Functions/CssMatrixValue.cs
index 6975cfe..ad3cfc5 100644
--- a/src/AngleSharp.Css/Values/Functions/CssMatrixValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssMatrixValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
     using System.Linq;
 
     /// <summary>
@@ -61,22 +62,26 @@ internal CssMatrixValue(ICssValue[] values)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssMatrixValue other)
         {
-            var count = _values.Length;
-
-            if (count == other._values.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _values[i];
-                    var b = other._values[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var count = _values.Length;
 
-                    if (!a.Equals(b))
+                if (count == other._values.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _values[i];
+                        var b = other._values[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Functions/CssMinMaxValue.cs b/src/AngleSharp.Css/Values/Functions/CssMinMaxValue.cs
index 9d7f9cf..a170245 100644
--- a/src/AngleSharp.Css/Values/Functions/CssMinMaxValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssMinMaxValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS minmax function call.
@@ -70,7 +71,13 @@ public CssMinMaxValue(ICssValue min, ICssValue max)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssMinMaxValue other)
         {
-            return _min.Equals(other._min) && _max.Equals(other._max);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_min, other._min) && comparer.Equals(_max, other._max);
+            }
+
+            return false;
         }
 
         ICssValue ICssValue.Compute(ICssComputeContext context)
diff --git a/src/AngleSharp.Css/Values/Functions/CssPerspectiveValue.cs b/src/AngleSharp.Css/Values/Functions/CssPerspectiveValue.cs
index 4b6ecf1..8df99ff 100644
--- a/src/AngleSharp.Css/Values/Functions/CssPerspectiveValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssPerspectiveValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the distance transformation.
@@ -57,7 +58,13 @@ internal CssPerspectiveValue(ICssValue distance)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssPerspectiveValue other)
         {
-            return _distance.Equals(other._distance);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_distance, other._distance);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssPerspectiveValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssRadialGradientValue.cs b/src/AngleSharp.Css/Values/Functions/CssRadialGradientValue.cs
index 133ced5..81959d9 100644
--- a/src/AngleSharp.Css/Values/Functions/CssRadialGradientValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssRadialGradientValue.cs
@@ -164,24 +164,28 @@ public ICssValue[] Arguments
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssRadialGradientValue other)
         {
-            if (_center.Equals(other._center) && _width.Equals(other._width) && _height.Equals(other._height) && _repeating == other._repeating && _sizeMode == other._sizeMode && _circle == other._circle)
+            if (other is not null)
             {
-                var count = _stops.Length;
-
-                if (count == other._stops.Length)
+                var comparer = EqualityComparer<ICssValue>.Default;
+                if (comparer.Equals(_center, other._center) && comparer.Equals(_width, other._width) && comparer.Equals(_height, other._height) && _repeating == other._repeating && _sizeMode == other._sizeMode && _circle == other._circle)
                 {
-                    for (var i = 0; i < count; i++)
-                    {
-                        var a = _stops[i];
-                        var b = other._stops[i];
+                    var count = _stops.Length;
 
-                        if (!a.Equals(b))
+                    if (count == other._stops.Length)
+                    {
+                        for (var i = 0; i < count; i++)
                         {
-                            return false;
+                            var a = _stops[i];
+                            var b = other._stops[i];
+
+                            if (!comparer.Equals(a, b))
+                            {
+                                return false;
+                            }
                         }
-                    }
 
-                    return true;
+                        return true;
+                    }
                 }
             }
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssRepeatValue.cs b/src/AngleSharp.Css/Values/Functions/CssRepeatValue.cs
index 07848f1..970068c 100644
--- a/src/AngleSharp.Css/Values/Functions/CssRepeatValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssRepeatValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS repeat function call.
@@ -70,7 +71,13 @@ public CssRepeatValue(ICssValue count, ICssValue value)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssRepeatValue other)
         {
-            return _count.Equals(other._count) && _value.Equals(other._value);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_count, other._count) && comparer.Equals(_value, other._value);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssRepeatValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssRotateValue.cs b/src/AngleSharp.Css/Values/Functions/CssRotateValue.cs
index 91f77a7..ccebf27 100644
--- a/src/AngleSharp.Css/Values/Functions/CssRotateValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssRotateValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the rotate3d transformation.
@@ -129,7 +130,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssRotateValue other)
         {
-            return _angle.Equals(other._angle) && _x.Equals(other._x) && _y.Equals(other._y) && _z.Equals(other._z);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_angle, other._angle) && comparer.Equals(_x, other._x) && comparer.Equals(_y, other._y) && comparer.Equals(_z, other._z);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssRotateValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssRunningValue.cs b/src/AngleSharp.Css/Values/Functions/CssRunningValue.cs
index a2aad04..3bb8b9f 100644
--- a/src/AngleSharp.Css/Values/Functions/CssRunningValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssRunningValue.cs
@@ -59,7 +59,7 @@ public CssRunningValue(String ident)
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssRunningValue other) => _ident.Equals(other._ident);
+        public Boolean Equals(CssRunningValue other) => other is not null && _ident == other._ident;
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssRunningValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssScaleValue.cs b/src/AngleSharp.Css/Values/Functions/CssScaleValue.cs
index e7b65a0..f9e3642 100644
--- a/src/AngleSharp.Css/Values/Functions/CssScaleValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssScaleValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the scale3d transformation.
@@ -136,7 +137,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssScaleValue other)
         {
-            return _sx.Equals(other._sx) && _sy.Equals(other._sy) && _sz.Equals(other._sz);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_sx, other._sx) && comparer.Equals(_sy, other._sy) && comparer.Equals(_sz, other._sz);
+            }
+
+            return false;
         }
 
         /// <summary>
diff --git a/src/AngleSharp.Css/Values/Functions/CssShapeValue.cs b/src/AngleSharp.Css/Values/Functions/CssShapeValue.cs
index 760fa41..af689ed 100644
--- a/src/AngleSharp.Css/Values/Functions/CssShapeValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssShapeValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS shape.
@@ -93,7 +94,13 @@ public CssShapeValue(ICssValue top, ICssValue right, ICssValue bottom, ICssValue
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssShapeValue other)
         {
-            return _top.Equals(other._top) && _right.Equals(other._right) && _bottom.Equals(other._bottom) && _left.Equals(other._left);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_top, other._top) && comparer.Equals(_right, other._right) && comparer.Equals(_bottom, other._bottom) && comparer.Equals(_left, other._left);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssShapeValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssSkewValue.cs b/src/AngleSharp.Css/Values/Functions/CssSkewValue.cs
index 46a7b22..1a8bd59 100644
--- a/src/AngleSharp.Css/Values/Functions/CssSkewValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssSkewValue.cs
@@ -3,6 +3,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the skew transformation.
@@ -107,7 +108,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssSkewValue other)
         {
-            return _alpha.Equals(other._alpha) && _beta.Equals(other._beta);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_alpha, other._alpha) && comparer.Equals(_beta, other._beta);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssSkewValue value && Equals(value);
@@ -118,7 +125,7 @@ public Boolean Equals(CssSkewValue other)
         /// <returns>The transformation matrix representation.</returns>
         public TransformMatrix ComputeMatrix(IRenderDimensions renderDimensions)
         {
-            var a = Math.Tan((_alpha as CssAngleValue ? ?? CssAngleValue.Zero).ToRadian());
+            var a = Math.Tan((_alpha as CssAngleValue? ?? CssAngleValue.Zero).ToRadian());
             var b = Math.Tan((_beta as CssAngleValue? ?? CssAngleValue.Zero).ToRadian());
             return new TransformMatrix(1.0, a, 0.0, b, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0);
         }
diff --git a/src/AngleSharp.Css/Values/Functions/CssStepsValue.cs b/src/AngleSharp.Css/Values/Functions/CssStepsValue.cs
index b416997..205b957 100644
--- a/src/AngleSharp.Css/Values/Functions/CssStepsValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssStepsValue.cs
@@ -105,7 +105,16 @@ public String CssText
         /// </summary>
         /// <param name="other">The value to check against.</param>
         /// <returns>True if both are equal, otherwise false.</returns>
-        public Boolean Equals(CssStepsValue other) => _start == other._start && _intervals.Equals(other._intervals);
+        public Boolean Equals(CssStepsValue other)
+        {
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return _start == other._start && comparer.Equals(_intervals, other._intervals);
+            }
+
+            return false;
+        }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssStepsValue value && Equals(value);
 
diff --git a/src/AngleSharp.Css/Values/Functions/CssSymbolsValue.cs b/src/AngleSharp.Css/Values/Functions/CssSymbolsValue.cs
index 7c13c7d..8f950e8 100644
--- a/src/AngleSharp.Css/Values/Functions/CssSymbolsValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssSymbolsValue.cs
@@ -53,7 +53,7 @@ public CssSymbolsValue(ICssValue type, List<String> entries)
         /// <summary>
         /// Gets the CSS text representation.
         /// </summary>
-        public String CssText =>Name.CssFunction(GetArgs());
+        public String CssText => Name.CssFunction(GetArgs());
 
         #endregion
 
@@ -66,22 +66,26 @@ public CssSymbolsValue(ICssValue type, List<String> entries)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssSymbolsValue other)
         {
-            var l = _entries.Count;
-
-            if (_type.Equals(other._type) && l == other._entries.Count)
+            if (other is not null)
             {
-                for (var i = 0; i < l; i++)
-                {
-                    var a = _entries[i];
-                    var b = other._entries[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var l = _entries.Count;
 
-                    if (!a.Equals(b))
+                if (comparer.Equals(_type, other._type) && l == other._entries.Count)
+                {
+                    for (var i = 0; i < l; i++)
                     {
-                        return false;
+                        var a = _entries[i];
+                        var b = other._entries[i];
+
+                        if (a != b)
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Functions/CssTranslateValue.cs b/src/AngleSharp.Css/Values/Functions/CssTranslateValue.cs
index 47c2df5..98ac81e 100644
--- a/src/AngleSharp.Css/Values/Functions/CssTranslateValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssTranslateValue.cs
@@ -4,6 +4,7 @@ namespace AngleSharp.Css.Values
     using AngleSharp.Css.Dom;
     using AngleSharp.Text;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the translate3d transformation.
@@ -106,7 +107,13 @@ public String Name
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssTranslateValue other)
         {
-            return _x.Equals(other._x) && _y.Equals(other._y) && _z.Equals(other._z);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_x, other._x) && comparer.Equals(_y, other._y) && comparer.Equals(_z, other._z);
+            }
+
+            return false;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssTranslateValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssUrlValue.cs b/src/AngleSharp.Css/Values/Functions/CssUrlValue.cs
index 14a1611..5f81555 100644
--- a/src/AngleSharp.Css/Values/Functions/CssUrlValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssUrlValue.cs
@@ -62,7 +62,7 @@ public CssUrlValue(String path)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssUrlValue other)
         {
-            return _path.Equals(other._path);
+            return other is not null && _path == other._path;
         }
 
         Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssUrlValue value && Equals(value);
diff --git a/src/AngleSharp.Css/Values/Functions/CssVarValue.cs b/src/AngleSharp.Css/Values/Functions/CssVarValue.cs
index 58723c8..04d9460 100644
--- a/src/AngleSharp.Css/Values/Functions/CssVarValue.cs
+++ b/src/AngleSharp.Css/Values/Functions/CssVarValue.cs
@@ -103,7 +103,13 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssVarValue other)
         {
-            return _defaultValue.Equals(other._defaultValue) && _variableName.Equals(other._variableName);
+            if (other is not null)
+            {
+                var comparer = EqualityComparer<ICssValue>.Default;
+                return comparer.Equals(_defaultValue, other._defaultValue) && _variableName == other._variableName;
+            }
+
+            return false;
         }
 
         /// <summary>
diff --git a/src/AngleSharp.Css/Values/Multiples/CssFlowRelativeValue.cs b/src/AngleSharp.Css/Values/Multiples/CssFlowRelativeValue.cs
index 804b17b..c436afa 100644
--- a/src/AngleSharp.Css/Values/Multiples/CssFlowRelativeValue.cs
+++ b/src/AngleSharp.Css/Values/Multiples/CssFlowRelativeValue.cs
@@ -91,22 +91,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssFlowRelativeValue<T> other)
         {
-            var count = _values.Length;
-
-            if (count == other._values.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _values[i];
-                    var b = other._values[i];
+                var comparer = EqualityComparer<T>.Default;
+                var count = _values.Length;
 
-                    if (!a.Equals(b))
+                if (count == other._values.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _values[i];
+                        var b = other._values[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Multiples/CssListValue.cs b/src/AngleSharp.Css/Values/Multiples/CssListValue.cs
index 8fcaef3..9c75eee 100644
--- a/src/AngleSharp.Css/Values/Multiples/CssListValue.cs
+++ b/src/AngleSharp.Css/Values/Multiples/CssListValue.cs
@@ -57,22 +57,26 @@ public CssListValue(T[] items = null)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssListValue<T> other)
         {
-            var count = _items.Length;
-
-            if (count == other._items.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _items[i];
-                    var b = other._items[i];
+                var comparer = EqualityComparer<T>.Default;
+                var count = _items.Length;
 
-                    if (!a.Equals(b))
+                if (count == other._items.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _items[i];
+                        var b = other._items[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Multiples/CssPeriodicValue.cs b/src/AngleSharp.Css/Values/Multiples/CssPeriodicValue.cs
index 600aae5..6502c19 100644
--- a/src/AngleSharp.Css/Values/Multiples/CssPeriodicValue.cs
+++ b/src/AngleSharp.Css/Values/Multiples/CssPeriodicValue.cs
@@ -111,22 +111,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssPeriodicValue<T> other)
         {
-            var count = _values.Length;
-
-            if (count == other._values.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _values[i];
-                    var b = other._values[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var count = _values.Length;
 
-                    if (!a.Equals(b))
+                if (count == other._values.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _values[i];
+                        var b = other._values[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Multiples/CssRadiusValue.cs b/src/AngleSharp.Css/Values/Multiples/CssRadiusValue.cs
index 5530bfb..1a15462 100644
--- a/src/AngleSharp.Css/Values/Multiples/CssRadiusValue.cs
+++ b/src/AngleSharp.Css/Values/Multiples/CssRadiusValue.cs
@@ -91,22 +91,26 @@ public String CssText
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssRadiusValue<T> other)
         {
-            var count = _values.Length;
-
-            if (count == other._values.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _values[i];
-                    var b = other._values[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var count = _values.Length;
 
-                    if (!a.Equals(b))
+                if (count == other._values.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _values[i];
+                        var b = other._values[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Multiples/CssTupleValue.cs b/src/AngleSharp.Css/Values/Multiples/CssTupleValue.cs
index c40b400..2653a3a 100644
--- a/src/AngleSharp.Css/Values/Multiples/CssTupleValue.cs
+++ b/src/AngleSharp.Css/Values/Multiples/CssTupleValue.cs
@@ -65,22 +65,26 @@ public CssTupleValue(T[] items = null, String separator = null)
         /// <returns>True if both are equal, otherwise false.</returns>
         public Boolean Equals(CssTupleValue<T> other)
         {
-            var count = _items.Length;
-
-            if (_separator.Equals(other._separator) && count == other._items.Length)
+            if (other is not null)
             {
-                for (var i = 0; i < count; i++)
-                {
-                    var a = _items[i];
-                    var b = other._items[i];
+                var comparer = EqualityComparer<ICssValue>.Default;
+                var count = _items.Length;
 
-                    if (!a.Equals(b))
+                if (_separator == other._separator && count == other._items.Length)
+                {
+                    for (var i = 0; i < count; i++)
                     {
-                        return false;
+                        var a = _items[i];
+                        var b = other._items[i];
+
+                        if (!comparer.Equals(a, b))
+                        {
+                            return false;
+                        }
                     }
-                }
 
-                return true;
+                    return true;
+                }
             }
 
             return false;
diff --git a/src/AngleSharp.Css/Values/Raws/CssAnyValue.cs b/src/AngleSharp.Css/Values/Raws/CssAnyValue.cs
index 7acbdb5..bf6c478 100644
--- a/src/AngleSharp.Css/Values/Raws/CssAnyValue.cs
+++ b/src/AngleSharp.Css/Values/Raws/CssAnyValue.cs
@@ -57,7 +57,7 @@ ICssValue ICssValue.Compute(ICssComputeContext context)
             return null;
         }
 
-        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssAnyValue o && _text.Equals(o.CssText);
+        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssAnyValue o && _text == o.CssText;
 
         #endregion
     }
diff --git a/src/AngleSharp.Css/Values/Raws/CssInitialValue.cs b/src/AngleSharp.Css/Values/Raws/CssInitialValue.cs
index c23e403..b01a184 100644
--- a/src/AngleSharp.Css/Values/Raws/CssInitialValue.cs
+++ b/src/AngleSharp.Css/Values/Raws/CssInitialValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents the CSS initial value.
@@ -45,7 +46,7 @@ public CssInitialValue(ICssValue value)
 
         ICssValue ICssValue.Compute(ICssComputeContext context) => this;
 
-        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssInitialValue o && _value.Equals(o.Value);
+        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssInitialValue o && EqualityComparer<ICssValue>.Default.Equals(_value, o.Value);
 
         #endregion
     }
diff --git a/src/AngleSharp.Css/Values/Raws/CssUnsetValue.cs b/src/AngleSharp.Css/Values/Raws/CssUnsetValue.cs
index 73a1f9e..74b9af9 100644
--- a/src/AngleSharp.Css/Values/Raws/CssUnsetValue.cs
+++ b/src/AngleSharp.Css/Values/Raws/CssUnsetValue.cs
@@ -2,6 +2,7 @@ namespace AngleSharp.Css.Values
 {
     using AngleSharp.Css.Dom;
     using System;
+    using System.Collections.Generic;
 
     /// <summary>
     /// Represents a CSS unset value.
@@ -48,7 +49,7 @@ ICssValue ICssValue.Compute(ICssComputeContext context)
             return this;
         }
 
-        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssUnsetValue o && _value.Equals(o.Value);
+        Boolean IEquatable<ICssValue>.Equals(ICssValue other) => other is CssUnsetValue o && EqualityComparer<ICssValue>.Default.Equals(_value, o.Value);
 
         #endregion
     }