In addition to the calming attributes of cool blue, this darker shade of blue may also carry some of the symbolism of green such as balance, harmony, and stability. It gets a little warmth and energy when paired with brownish or reddish shades of orange. Brown is a natural, down-to-earth neutral color. Red and cyan are opposites on the color wheel with high contrast, but they aren't necessarily a great combination. Moving from red to orange and to darker blues provide a more pleasing palette.
From darkest to lightest, the red-orange shown with each blue swatch in the above image are:
- Deep Orange Red Hex #CD3700 | RGB 205,55,0
- Cadmium Orange Hex #FF6103 | RGB 255,97,3
- Numbers: Red Hex #FF0000 | RGB 255,0,0 (SVG/CSS color keyword red)
- Dark Royal Blue Hex #27408B | RGB 39,64,139
- Deep Sky Blue Hex #00688B | RGB 0,104,139 (not color keyword deepskyblue)
- Dark Slate Blue Hex #2F4F4F RGB 47,79,79 (not color keyword darkslateblue)
- Dark Cyan Hex #008B8B | RGB 0,139,139 (the greener side of blue)
- Manganese Blue Hex #03A89E | RGB 3,168,158 (a blue turquoise color)
- Cyan (Aqua) Hex #00FFFF | RGB 0,255,255 (SVG color keyword cyan or aqua; a blue-green color)
You don't have to use these exact shades. Go a touch lighter or darker, or step one spot to the left or the right on the color wheel. These color combinations are just to help you find a suitable color palette using dark blue as the main component.