body.dark-mode {
    background-color: #1f1f1f; /* Dark mode primary color */
}

/* For light mode, the primary color is white (FFFFFF).
   We assume the theme's default background is white, so we only need to specify dark mode changes.
   If specific elements within the theme also need their background adjusted to #1f1f1f in dark mode,
   those would need to be identified and targeted individually. */