**Design Concepts:** 1. **T-shirt (Top Left):** - Change the neckline to a subtle V-neck. - Add a small pocket on the left chest area. 2. **Long Sleeve Shirt (Top Right):** - Opt for a crew neck instead of a round neck. - Incorporate a button detail on the sleeves, highlighting a slight cuff. 3. **Hoodie (Bottom Left):** - Remove the kangaroo pocket, replacing it with side seam pockets. - Introduce a wider hood for a more relaxed fit. 4. **Polo Shirt (Bottom Right):** - Eliminate the collar and switch to a round neck for a more casual look. - Add a subtle pattern or texture detail to the fabric. **Color Palette:** - Use earthy tones like olive green, rust, soft beige, and navy for a more timeless appeal.