Act as a product designer with 5+ years of experience in kitchen gadgets. Design a portable salad spinner that includes a built-in freshness indicator to help users track the shelf life of their greens. The spinner should be [LIGHTWEIGHT], [COMPACT], and made from [ECO-FRIENDLY MATERIALS]. The freshness indicator should use [COLOR-CHANGING TECHNOLOGY] to visually signal when the greens are no longer fresh. Include features like [ONE-HAND OPERATION], [LEAK-PROOF LID], and [STACKABLE DESIGN] for easy storage. Render the product in a modern, minimalist style with a focus on functionality and aesthetics. Show it in a real-life kitchen setting with natural lighting to highlight its practicality.