AngleSharp by Florian Rappl

<PackageReference Include="AngleSharp" Version="0.8.4.1" />

.NET API 1,229,312 bytes

 CssTransformStyleProperty

Information can be found on MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/transform-style Gets if the children of the element are lying in the plane of the element itself. Otherwise the children of the element should be positioned in the 3D-space.
using AngleSharp.Css; using AngleSharp.Extensions; namespace AngleSharp.Dom.Css { internal sealed class CssTransformStyleProperty : CssProperty { private static readonly IValueConverter<bool> Converter = Converters.Toggle(Keywords.Flat, Keywords.Preserve3d); internal CssTransformStyleProperty(CssStyleDeclaration rule) : base(PropertyNames.TransformStyle, rule, PropertyFlags.None) { } protected override object GetDefault(IElement element) { return true; } protected override object Compute(IElement element) { return Converter.Convert(base.Value); } protected override bool IsValid(CssValue value) { return Converter.Validate(value); } } }