Hex Editor allows you to set colors of almost every editor window's element. Select an element in a list and then select a color using color picker control. You can also set the color to "automatic". The sample window layout below immediately reflects changes you make. Pressing Apply button also immediately applies your current coloring scheme to all opened editor windows. The color of the following elements may be customized:

Text - the color of text in data and text panes.
Background - the color of window background. If interlacing is used, rows or columns use "Even column/row" and "Odd column/row" colors instead. Background color is still used for the rest of the window.
Address - address area text color.
Address background - address area background color.
ASCII/UNICODE text - color of the text in text pane.
ASCII/UNICODE background - text pane background color.
Even column/row (for interlaced modes) - background color for even columns or rows. Used in interlaced modes.
Odd column/row (for interlaced modes) - background color for odd columns or rows. Used in interlaced modes.
"No data" text - text color for the "empty" file data.
Cursor fill - cursor fill color.
Cursor outline - cursor outline color.
Active row & column highlight text - row/column text highlight color.
Active row & column highlight background - row/column background highlight color.
Changed text - text color for changed cells.
Changed background - background color for changed cells.
Changed outline - outline color for changed cells.
Selection - color of selection. Selection color's alpha must allow proper color mixing, so selected data is clearly visible.