More properties, cleanup

src/commonMain/kotlin/nl/astraeus/css/properties/Caption.kt

@@ -0,0 +1,14 @@
+package nl.astraeus.css.properties
+
+class CaptionSide(
+    value: String
+): CssProperty(value) {
+
+    companion object {
+        fun top() = BoxSizing("top")
+        fun bottom() = BoxSizing("bottom")
+        fun initial() = BoxShadow("initial")
+        fun inherit() = BoxShadow("inherit")
+    }
+
+}