[css-box-3] Fix computed value, add animation type line.

Author: fantasai

css-box-3/Overview.bs

@@ -223,7 +223,8 @@ Page-relative (Physical) Margin Properties: the 'margin-top', 'margin-right', 'm
 		Applies to: all elements except <a>internal table elements</a>
 		Inherited: no
 		Percentages: refer to <a>logical width</a> of containing block
-		Computed value: absolute length
+		Computed value: the keyword ''auto'' or an absolute length and/or percentage combination
+		Animation type: per computed value
 	</pre>
 
 	These properties set the top, right, bottom, and left
@@ -242,7 +243,8 @@ Margin Shorthand: the 'margin' property {#margin-shorthand}
 		Applies to: all elements except <a>internal table elements</a>
 		Inherited: no
 		Percentages: refer to <a>logical width</a> of containing block
-		Computed value: absolute length
+		Computed value: see individual properties
+		Animation type: per computed value
 	</pre>
 
 	The 'margin' property is a shorthand property for setting
@@ -314,7 +316,8 @@ Page-relative (Physical) Padding Properties: the 'padding-top', 'padding-right',
 		Applies to: all elements except <a>internal table elements</a>
 		Inherited: no
 		Percentages: refer to <a>logical width</a> of containing block
-		Computed value: absolute length
+		Computed value: an absolute length and/or percentage combination
+		Animation type: per computed value
 	</pre>
 
 	These properties set the top, right, bottom, and left
@@ -332,7 +335,8 @@ Padding Shorthand: the 'padding' property {#padding-shorthand}
 		Applies to: all elements except <a>internal table elements</a>
 		Inherited: no
 		Percentages: refer to <a>logical width</a> of containing block
-		Computed value: absolute length
+		Computed value: see individual properties
+		Animation type: per computed value
 	</pre>
 
 	The 'padding' property is a shorthand property for setting