Colors can be considered warm or cool and this depends on how they make you feel, not by the fact they are dark or light colors.
- Warm colors tend to move forward, appear larger and are either related to the color red or have red mixed in its color base.
- Cool colors are recede and are related to or contain the color blue.
- Neutral colors such as grays and blacks can be either warm or cool and can be adapted to suit the design.
For example, natural objects work better with warm blacks and grays while man-made objects work well with cool blacks and grays. A balance of warm and cool colors will create a dynamic design and sense of depth. Proportions and surrounding warms and cools will change how your design feels and how each individual color feels when in direct relation to another color.
In terms of emotion, you may want to consider what your colors combinations are projecting to your audience. Black and white offer sharp contrast (large difference between dark to light) and are the most clear, producing the effect of precision, firmness, objectivity and alertness. Colors close in value (low contrast) produce the feeling of haziness, softness, quiet, rest, introspection while greater contrast between colors offers something similar to that of what black and white achieves, but with more interest, fun, movement, and depth. Dark colors can relate to the night, mystery and fear just as light colors create illumination, clarity, optimism.
What do your colors say about you, your branding and your website? Is your current color choice hindering conversions by eliciting the wrong emotions in your users?