One color is enough. Add up to two more if your brand has them; the page fills the rest of the palette to match.
Its colors and font fill the steps below, and its visual styles replace the built-in ones. What you change on this page is added on top. Or pick a PBIP report folder and the page finds the theme the report uses, and lists its visuals in Step 3.
Change any data color. Don’t like a suggested one? Other options under it lists colors that fit instead. Then choose the page and visual backgrounds, text, good and bad colors and the font. Everything else in the theme follows from these.
The ratio on each color is its contrast with the background it sits on: how much it stands out, from 1:1 (invisible) to 21:1 (black on white). 4.5:1 or more is readable as text, such as titles and labels. 3:1 to 4.5:1 is fine for bars, lines and slices, but too light for text. Under 3:1 is hard to see; keep it for big shapes or less important series.
Used for waterfall increases and decreases, KPI status, and conditional formatting. The default is the dark green, dark yellow and dark red text colors from Excel’s conditional formatting.
For a line and clustered column chart that shows a bubble with a label over each column. Power BI’s default marker is too small for that, so the theme sets it. Only markers you turn on change, and only in that chart type.
How visuals look when you add them. Start with the common settings for all visuals or one kind of visual. For more, copy the formatting of a visual from your own report, or set any property the theme file takes. Leave a setting as it is to keep the theme’s default.
Format a visual the way you want in a sample report saved as a PBIP project. Read it here and its formatting becomes the theme’s default for that kind of visual, so every report with the theme gets it. Styles for hover and selected come too. Title text, and colors set for one series or by a field, stay behind; each visual says what was left out and why.
Every formatting option a theme file can set, for every visual, from Microsoft’s theme schema. What you set here wins over everything above. Leave a box empty to keep the theme’s value, shown in grey.
A sketch of a report page with the theme applied, to judge the colors together. Power BI’s own rendering will differ in detail.
The theme file includes your colors, font, text styles, icons and formatting for 27 visual types and the page, with your visual settings from Step 3.