gnome-shell-dark-theme/gnome-shell-sass/_colors.scss

// When color definition differs for dark and light variant,
// it gets @if-ed depending on $variant

@import '_palette.scss';

$is_highcontrast:false;

// base color for light theme
$_dark_base_color: desaturate($dark_4, 100%);

$base_color: if($variant == 'light', $light_1, $_dark_base_color);
$bg_color: if($variant == 'light', $light_2, lighten($base_color, 5%));
$fg_color: if($variant == 'light', $_dark_base_color, white);

$selected_fg_color: $light_1;
$selected_bg_color: $blue_3;
$selected_borders_color: if($variant== 'light', darken($selected_bg_color, 15%), darken($selected_bg_color, 20%));

$borders_color: if($variant == 'light', transparentize($fg_color, .85), transparentize($fg_color, .9));
$outer_borders_color: if($variant == 'light', darken($bg_color, 7%), lighten($bg_color, 5%));

$link_color: if($variant == 'light', darken($selected_bg_color, 10%), lighten($selected_bg_color, 20%));
$link_visited_color: if($variant == 'light', darken($selected_bg_color, 20%), lighten($selected_bg_color, 10%));

$warning_color: if($variant == 'light', $yellow_4, $yellow_3);
$error_color: if($variant == 'light', $red_4, $red_3);
$success_color: if($variant == 'light', $green_4, $green_5);
$destructive_color: $error_color;

// color definitions for OSD elements
$osd_fg_color: $light_1;
$osd_bg_color: lighten($_dark_base_color, 5%);

// derived osd colors
$osd_insensitive_bg_color: transparentize(mix($osd_fg_color, opacify($osd_bg_color, 1), 10%), 0.5);
$osd_insensitive_fg_color: mix($osd_fg_color, $osd_bg_color, 70%);
$osd_borders_color: transparentize($osd_fg_color, 0.9);
$osd_outer_borders_color: transparentize($osd_fg_color, 0.98);

$shadow_color: if($variant == 'light', rgba(0,0,0,.05), rgba(0,0,0,0.2));

// buttons
$button_mix_factor: if($variant == 'light', 12%, 9%);

// notifications
$bubble_buttons_color: if($variant == 'light', darken($bg_color, 7%), lighten($bg_color, 5%));

// color definitions for system elements (e.g. the overview)
$system_base_color: $_dark_base_color; // always dark
$system_fg_color: $light_2;

// derived system colors
$system_bg_color: lighten($system_base_color, 5%);
$system_borders_color: transparentize($system_fg_color, .9);
$system_insensitive_fg_color: mix($system_fg_color, $system_bg_color, 50%);
$system_overlay_bg_color: mix($system_base_color, $system_fg_color, 90%); // for non-transparent items, e.g. dash

// derived global colors
// insensitive state
$insensitive_fg_color: if($variant == 'light', mix($fg_color, $bg_color, 60%),  mix($fg_color, $bg_color, 50%));
$insensitive_bg_color: mix($bg_color, $base_color, 60%);
$insensitive_borders_color: mix($borders_color, $base_color, 60%);

// checked state
$checked_bg_color: if($variant=='light', darken($bg_color, 7%), lighten($bg_color, 7%));
$checked_fg_color: if($variant=='light', darken($fg_color, 7%), lighten($fg_color, 7%));

// hover state
$hover_bg_color: if($variant=='light', darken($bg_color,9%), lighten($bg_color, 10%));
$hover_fg_color: if($variant=='light', darken($fg_color,9%), lighten($fg_color, 10%));

// active state
$active_bg_color: if($variant=='light', darken($bg_color, 11%), lighten($bg_color, 12%));
$active_fg_color: if($variant=='light', darken($fg_color, 11%), lighten($fg_color, 12%));