How to detect CSS inheritance source?

So far, I can only tell if a property is inherited or not, but I need to know the source of inheritance, (for ex, which CSS file caused the final value ?) is this possible ?

Is there a handy tool for this ?

EDIT

Here is what I get in chrome Computed Style (show inheritance) See the direction property, there is no info about its inheritance source

Sampath

You can do this job very easily by using Firebug in Firefox or Chrome's Developer Tools.

Chrome Developer Tools

Like image shows below.

For more information check Chrome Developer Tools: Element Styles Here

In Firebug

Like image shows below.

For more information check CSS Development Here

You can install Fire Bug From Here

Update 1:

You can find it by just clicking Show Inherited check box on Chrome's computed style panel likes below.

Update 2:

In Firebug, you just click inherited element what I showed below image.Then It will guide you to the relevant Inherited element's location.

P.S. - Same can do by using chrome Tool.

The cascading nature of CSS makes the Styles browser in the Elements Tab very useful, you can see the individual styles and where they come from, you can also see the final set of styles after it is computed and applied to the element.