Struggling to color a simple clipart in Designer - Glad for any suggestions

[woodgrim]

Hello! I'm very new to this kind of stuff so maybe this is a dumb question. I made a simple "at the beach" clipart and I'm struggling to color the sand at the bottom of the picture. 

First I tried to add an invisible vector area but it looked very bad. Is there a way to extend the small area under the sand curves or do I have to work with invisible vector areas to color the area below with sand color?

[GarryP]

The fill of a non-closed vector curve will only extend to a straight line between the ends of the curve.

Unless anyone has a better suggestion I would use a separate filled curve – without a stroke – behind the original curve, as you suggest.

I can think of one way to do it without a separate curve but it’s a bit of a nasty ‘trick’ which needs careful planning and manipulation, and doesn’t look particularly good anyway, under most circumstances, see attached image.