Certainly! Here’s an adjusted color palette with muted tones and an off-white cream instead of pure white and deep black.

 <Muted Terracotta and Green Temples>
1. Muted Terracotta - 
                            
                            #C57B64
                         - A softer, earthy tone reminiscent of aged clay, providing warmth without being overpowering.
2. Muted Leafy Green - 
                            
                            #6E9A4A
                         - A subdued green that still reflects nature, offering a gentle touch.
3. Muted Sky Blue - 
                            
                            #A0C4D4
                         - A calm, muted blue that conveys the feeling of a clear sky without being too bright.
4. Off-White Cream - 
                            
                            #F5F0E1
                         - A warm, inviting cream that adds brightness and a soft contrast to the palette.
5. Charcoal Grey - 
                            
                            #3B3B3B
                         - A softer alternative to black, providing depth without harshness.

This palette maintains the nostalgic warm bright mood while incorporating the desired muted tones and off-white cream.

Would you like any further adjustments or suggestions for how to best utilize this palette in your photobook design?