Very well done. Great use of color and varying up the tones in the distance and in the shadows it creates really good depth and keeps it very fun to look at, especially in portions of the clouds.
I think the foreground can be brought out a bit more, especially the plants on the right corner the top of the stalks sort of blend into the hillside a bit and the tall grass's yellow is very close the hillside as well.
The biggest issue I have with this is that its so small, I think in general a good size for submissions like this is a width between 700 pixels and 1500 pixels definitely no less than 700. That way it keeps all the detail and lets users fill their screens to really look at the drawing. Also a smaller personal issue for me is the visible spiral at the top, little things like that do have slight effects on the way drawings are viewed and judged, so just bit of cropping will help if you had the time, or to keep in mind for the future.
Keep up the great work!
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