Tham khảo tài liệu 'html & css: the complete reference- p17', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 776 Part III Appendixes Color Format Description Examples RGB CSS colors can also be defined using the keyword rgb followed by three numbers between 0 and 255 contained in parentheses and separated by commas with no spaces between them. RGB color values can also be defined using percentages. The format is the same except that the numbers are replaced by percentage values between 0 and 100 . p1 color rgb 204 0 51 p color rgb 0 10 50 RGBa Color Like RBG color but this adds an alpha channel value to specify the opacity of the color. An RGBa is specified via a function style rgba r g b a value where colors r g and b are specified as decimal values from 0 to 255 or a percentage from 0 to 100 and the alpha channel value for defining opacity is a number between 0 fully transparent and 1 fully opaque . Values outside this range will be rounded up or down to fit the closest value. redtrans color rgba 255 0 0 Table C-4 CSS Color Values continued NOTE Testing reveals that depending on operating system color changes some browsers may not map these UI color names correctly and often default to black. CSS Color-Related Properties Numerous CSS properties allow for color values. Table C-6 lists each property a brief example of its use and an indication in which CSS version the property first appeared. Readers looking for more information about the usage of these properties should see Chapters 5 and 6 which provide a reference for standard and emerging or nonstandard CSS properties respectively. NOTE Some details about browser and version support particularly in regard to the CSS 3 related properties are omitted from Table C-6. The purpose here is to provide a simple cross-reference. See Chapters 5 and 6 for a complete discussion of each property. r- r-s r i i n a__ _ir X _ Xl_ __X _ _ Appendix C Colors 777 UI Color Name Description ActiveBorder Active window border color ActiveCaption Active window caption color AppWorkspace Background
