Illustrator drop shadow around paths

Question

I have this icon with 2 paths how can I add shadow only to the outter of the balloon?

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Answer 1

You can achieve this using Expand Appearance and Opacity Mask feature. Create a solid shape using your existing balloon shapes (you can use Shape Builder tool).

Then move this solid shape layer behind your balloon group/layers. Apply the shadow effect using Appearance (fx) panel. You should see something like this:

Go to Object > Expand Appearance. Select just the solid shape layer again (not the expanded shadow) and copy it (to clipboard for later use in next step).

Then select the expanded shadow layer and make it an Opacity Mask using Transparency panel and paste the solid shape you had copied, so it will hide the inside shadow. You'll get a result like this.

I don't know why you're using this shadow, but you'll need to tweak the mask a bit at the top because it looks unnatural and a bit ugly right now. Maybe using additional softer shadow layer at top so it doesn't look very sharp on top of the balloon. But that's the trick I'd use for similar result.

Answer 2

You can just draw a path using pen tool around the outer balloon. Use like 5 to 10 px for the stroke option and the color is black. Then expand it. Expanding will make it a normal shape. Then using effects, use gaussian blur effect. Please use preview option on the gaussian blur panel. It'll show you how wider the shadow effect become. And then if you want, you can change the opacity to get how darker you want the shadow effect. Also if it is not darker like you expected you can copy and paste above on the same object. It's give a more darker drop shadow.