Color Palette:
1. Light Blue: 
          
          #ADD8E6
        - A soft and calming blue for background
2. Dark Blue: 
          
          #4169E1
        - A rich and deep blue for highlighting
3. Light Green: 
          
          #90EE90
        - A fresh and vibrant green for positive data
4. Dark Green: 
          
          #008000
        - A bold and strong green for contrast
5. Light Yellow: 
          
          #FFFFE0
        - A gentle and warm yellow for emphasis
6. Dark Yellow: 
          
          #FFD700
        - A bright and vivid yellow for visibility
7. Light Purple: 
          
          #E6E6FA
        - A delicate and soothing purple for variety
8. Dark Purple: 
          
          #800080
        - A royal and elegant purple for sophistication
9. Light Orange: 
          
          #FFDAB9
        - A cheerful and energetic orange for attention
10. Dark Orange: 
          
          #FFA500
        - A fiery and bold orange for impact
11. Light Gray: 
          
          #D3D3D3
        - A neutral and versatile gray for balance
12. Dark Gray: 
          
          #A9A9A9
        - A sleek and modern gray for contrast

Description: This color palette provides a range of accessible light and dark variants for line chart data visualization. The colors are carefully selected to ensure clarity, contrast, and visual appeal in presenting data effectively.