I don’t know why, but there are heaps of colors available in Word for formatting text and lines but only a small subset of colors are available in Excel. Does Microsoft think we don’t like color in Excel?
Unfortunately we can’t specify additional colours for use in Excel workbooks either but we can change the colours that are displayed in the color palette to a mix of what we do like. So, if pink isn’t your thing, you can replace all the pinks with colors you do like and will use.
To do this, in Excel, choose Tools, Options, Color tab and select a color to change. Click Modify to choose a new color in its place. Repeat as desired.