Chart Colors
The Colors page has the following options:
Palette: this option allows you to select one of several palettes of colors for your chart.
Theme: selecting a theme controls many aspects of the chart, including the colors of data items, background, and legend, the size and style of the border, and so on.
Grid bars: turn this option on to display alternating horizontal bands in the chart. Click the first colored button to specify the color of the first band and the second button for the color of the second.