Nail the exact color periwinkle in your design by using the code from any one of these systems for color identification.
|RGB||r: 204, g: 204, b: 255|
|HSL||h: 240°, s: 100%, l: 90%|
|HSV||h: 240°, s: 20%, v: 100%|
|CMYK||c: 20%, m: 20%, y: 0%, k: 0%|
If you're identifying color for pretty much anything digital, you're working in an RGB colorspace. If the project you're working on requires percentage representation, periwinkle is made of 80% red, 80% green, and 100% blue.
If you're identifying color for a print project, you're most likely using a CMYK colorspace—the percentages are 20% cyan, 20% magenta, 0% yellow, 0% black.