Version: 2023.1
Language : English
Introduction to USS built-in variables
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USS built-in variable references

The following tables list all the USS built-in variables.

metrics

Group Role/Control Name Description Professional Personal Runtime
metrics
--unity-metrics-default-border_radius The default border radius for controls 3px 3px 0px
--unity-metrics-default-font_big_size The big font size 14px 14px 15px
--unity-metrics-default-font_normal_size The normal font size 12px 12px 14px
--unity-metrics-default-font_semi_small_size The semi small font size 11px 11px 13px
--unity-metrics-default-font_small_size The small font size 10px 10px 12px
--unity-metrics-default-font_tiny_size The tiny font size 9px 9px 11px
--unity-metrics-default-font_very_big_size The very big font size 19px 19px 21px
--unity-metrics-inspector_titlebar-height The height of a title bar in an InspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
See in Glossary
view
22px 22px Undefined
--unity-metrics-single_line-height The usual height for a single-line Editor control, for example, a one-line text field.
See EditorGUIUtility.singleLineHeight
18px 18px Undefined
--unity-metrics-single_line_large-height The usual height for a large single-line Editor control, for example, an Inspector title bar label 20px 20px Undefined
--unity-metrics-single_line_small-height The usual height for a small single-line Editor control, for example, a mini toggle or a mini text field 16px 16px Undefined
--unity-metrics-toolbar-height The height of a toolbarA row of buttons and basic controls at the top of the Unity Editor that allows you to interact with the Editor in various ways (e.g. scaling, translation). More info
See in Glossary
control
21px 21px Undefined
--unity-metrics-toolbar_button-height The height of a toolbar button control 20px 20px Undefined
****
--current-font UIPackageResources/Fonts/Inter/Inter-Regular SDF.asset UIPackageResources/Fonts/Inter/Inter-Regular SDF.asset Undefined
colors
alternated_rows
--unity-colors-alternated_rows-background The alternate background color for views with alternating row colors #3F3F3F #CACACA Undefined
app_toolbar
--unity-colors-app_toolbar-background The background color for the main toolbar #191919 #8A8A8A Undefined
app_toolbar_button
--unity-colors-app_toolbar_button-background The background color for a button in the main toolbar #383838 #C8C8C8 Undefined
--unity-colors-app_toolbar_button-background-checked The background color for a button in the main toolbar when it is checked #6A6A6A #656565 Undefined
--unity-colors-app_toolbar_button-background-hover The background color for a button in the main toolbar when the mouse pointer hovers over them #424242 #BBBBBB Undefined
--unity-colors-app_toolbar_button-background-pressed The background color for a button in the main toolbar when it is pressed #6A6A6A #656565 Undefined
--unity-colors-app_toolbar_button-border The border color for a button in the main toolbar #191919 #6B6B6B Undefined
--unity-colors-app_toolbar_button-border_accent The accent border color for a button in the main toolbar #222222 #6B6B6B Undefined
box
--unity-colors-box-background The background color for a box control rgba(40, 40, 40, 0.3019608) rgba(185, 185, 185, 0.9019608) #DEDEDE
--unity-colors-box-border The border color for a box control transparent transparent #555555
button
--unity-colors-button-background The background color for a button control #585858 #E4E4E4 #BCBCBC
--unity-colors-button-background-disabled Undefined Undefined #959595
--unity-colors-button-background-focus The background color for a button control when it has focus #6E6E6E #BEBEBE Undefined
--unity-colors-button-background-hover The background color for a button control when the mouse pointer hovers over it #676767 #ECECEC #D1D1D1
--unity-colors-button-background-hover_pressed The background color for a button control when it is hoverd and pressed #4F657F #B0D2FC Undefined
--unity-colors-button-background-pressed The background color for a button control when it is pressed #46607C #96C3FB #959595
--unity-colors-button-border The border color for a button control #303030 #B2B2B2 #959595
--unity-colors-button-border_accent The border accent color for a button control #242424 #939393 Undefined
--unity-colors-button-border_accent-focus The border accent color used for a button control when focused #7BAEFA #018CFF Undefined
--unity-colors-button-border-disabled Undefined Undefined #7E7E7E
--unity-colors-button-border-focus Undefined Undefined #006AA6
--unity-colors-button-border-hover Undefined Undefined #808080
--unity-colors-button-border-pressed The border color for a button control when it is pressed #0D0D0D #707070 #646464
--unity-colors-button-text The text color for a button control #EEEEEE #090909 #1B1B1B
--unity-colors-button-text-disabled Undefined Undefined #2D2D2D
default
--unity-colors-default-background The default background color for controls #282828 #A5A5A5 Undefined
--unity-colors-default-border The default border color for controls #232323 #999999 #959595
--unity-colors-default-text The default text color #D2D2D2 #090909 #1B1B1B
--unity-colors-default-text-hover The default text color when the mouse pointer hovers over the text #BDBDBD #090909 Undefined
dropdown
--unity-colors-dropdown-background The background color for a dropdown control #515151 #DFDFDF #DFDFDF
--unity-colors-dropdown-background-hover The background color for a dropdown control when the mouse pointer hovers over it #585858 #E4E4E4 #E8E8E8
--unity-colors-dropdown-border The border color for a dropdown control #303030 #B2B2B2 #999999
--unity-colors-dropdown-border_accent The border accent color for a dropdown control #242424 #939393 #939393
--unity-colors-dropdown-text The text color for a dropdown control #E4E4E4 #090909 #1B1B1B
error
--unity-colors-error-text The text color for error messages #D32222 #5A0000 Undefined
headerbar
--unity-colors-headerbar-background The background color for a header bar control #3C3C3C #CBCBCB #BCBCBC
headerbar_column
--unity-colors-headerbar_column-background The background color used for a column control in a header bar #3C3C3C #CBCBCB #BCBCBC
--unity-colors-headerbar_column-background-hover The background color used for a button control when hovered over #464646 #C1C1C1 #D1D1D1
--unity-colors-headerbar_column-background-pressed The background color used for a button control when pressed #505050 #EFEFEF #959595
helpbox
--unity-colors-helpbox-background The background color for a helpbox control rgba(96, 96, 96, 0.2039216) rgba(235, 235, 235, 0.2039216) Undefined
--unity-colors-helpbox-border The border color for a helpbox control #232323 #A9A9A9 Undefined
--unity-colors-helpbox-text The text color for a helpbox control #BDBDBD #161616 Undefined
highlight
--unity-colors-highlight-background The background color for selected items or selected text #2C5D87 #3A72B0 Undefined
--unity-colors-highlight-background-hover The background color for items when the mouse pointer hovers over them rgba(256, 256, 256, 0.0627451) rgba(0, 0, 0, 0.0627451) Undefined
--unity-colors-highlight-background-hover-lighter #5F5F5F #9A9A9A Undefined
--unity-colors-highlight-background-inactive The background color for selected items or selected text when the control does not have focus #4D4D4D #AEAEAE Undefined
--unity-colors-highlight-text The text color for selected items or selected text #4C7EFF #0032E6 Undefined
--unity-colors-highlight-text-inactive The text color for selected items or selected text when the control does not have focus #FFFFFF #FFFFFF Undefined
input_field
--unity-colors-input_field-background The background color for an input field control #2A2A2A #F0F0F0 #F0F0F0
--unity-colors-input_field-background-disabled Undefined Undefined #D1D1D1
--unity-colors-input_field-border The border color for an input field control #212121 #B7B7B7 #646464
--unity-colors-input_field-border_accent The border accent color for an input field control #0D0D0D #A0A0A0 Undefined
--unity-colors-input_field-border-focus The border color for an input field control when it has focus #3A79BB #1D5087 #006AA6
--unity-colors-input_field-border-hover The border color for an input field control when the mouse pointer hovers over it #656565 #6C6C6C #323232
--unity-colors-input_field-text-disabled Undefined Undefined #585858
inspector_titlebar
--unity-colors-inspector_titlebar-background The background color for a title bar in an Inspector view #3E3E3E #CBCBCB Undefined
--unity-colors-inspector_titlebar-background-hover The background color for a title bar in an Inspector view when the mouse pointer hovers over it #474747 #D6D6D6 Undefined
--unity-colors-inspector_titlebar-border The border color for a title bar in an Inspector view #1A1A1A #7F7F7F Undefined
--unity-colors-inspector_titlebar-border_accent The border accent color for a title bar in an Inspector view #303030 #BABABA Undefined
label
--unity-colors-label-text The text color for a label control #C4C4C4 #090909 #1B1B1B
--unity-colors-label-text-disabled Undefined Undefined #585858
--unity-colors-label-text-focus The text color for a label when it has focus #81B4FF #003C88 #00526A
link
--unity-colors-link-text The text color for unvisited links #4C7EFF #4C7EFF Undefined
minmax_slider_thumb
--unity-colors-minmax_slider_thumb-background Undefined Undefined #BCBCBC
object_field
--unity-colors-object_field-background The background color for an object field control #282828 #EDEDED Undefined
--unity-colors-object_field-border The border color for an object field control #202020 #B0B0B0 Undefined
--unity-colors-object_field-border-focus The border color for an object field control when it has focus #3A79BB #1D5087 Undefined
--unity-colors-object_field-border-hover The border color for an object field control when the mouse pointer hovers over it #656565 #6C6C6C Undefined
object_field_button
--unity-colors-object_field_button-background The background color for the button in an object field control #373737 #DEDEDE Undefined
--unity-colors-object_field_button-background-hover The background color for the button in an object field control when the mouse pointer hovers over it #4C4C4C #CCCCCC Undefined
play_mode
--unity-colors-play_mode-background The color used to tint the UI(User Interface) Allows a user to interact with your application. Unity currently supports three UI systems. More info
See in Glossary
in Play Mode
#606060 #ECECEC Undefined
popup
--unity-colors-popup-background The background color for a popup window #313131 #C1C1C1 Undefined
preview
--unity-colors-preview-background The background color for a preview control #313131 #C1C1C1 Undefined
--unity-colors-preview-border The border color for a preview control #232323 #999999 Undefined
--unity-colors-preview-text The text color for a preview control #BDBDBD #090909 Undefined
preview_overlay
--unity-colors-preview_overlay-text The text color for a preview control overlay #DEDEDE #FFFFFF Undefined
progress
--unity-colors-progress-background #303030 #606060 Undefined
progress_bar
--unity-colors-progress_bar-background Undefined Undefined #BCBCBC
--unity-colors-progress_bar-border Undefined Undefined #808080
--unity-colors-progress_bar-text Undefined Undefined #1B1B1B
progress_bar_progress
--unity-colors-progress_bar_progress-background Undefined Undefined #E7E7E7
scrollbar_button
--unity-colors-scrollbar_button-background The background color for a scrollbar’s scroll buttons rgba(0, 0, 0, 0.05098039) rgba(0, 0, 0, 0.05098039) #F0F0F0
--unity-colors-scrollbar_button-background-hover The background color for a scrollbar’s scroll buttons when the mouse pointer hovers over them #494949 #A7A7A7 #E7E7E7
--unity-colors-scrollbar_button-border Undefined Undefined #959595
--unity-colors-scrollbar_button-border-focus Undefined Undefined #006AA6
--unity-colors-scrollbar_button-border-hover Undefined Undefined #959595
scrollbar_groove
--unity-colors-scrollbar_groove-background The background color for a scrollbar’s groove (background) rgba(0, 0, 0, 0.05098039) rgba(0, 0, 0, 0.05098039) #BCBCBC
--unity-colors-scrollbar_groove-border The border color for a scrollbar’s groove rgba(0, 0, 0, 0.1019608) rgba(0, 0, 0, 0.1019608) #959595
scrollbar_thumb
--unity-colors-scrollbar_thumb-background The background color for a scrollbar’s thumb/handle #5F5F5F #9A9A9A #E7E7E7
--unity-colors-scrollbar_thumb-background-hover The background color for a scrollbar’s thumb/handle when the mouse pointer hovers over it #686868 #8E8E8E #F0F0F0
--unity-colors-scrollbar_thumb-background-pressed Undefined Undefined #F0F0F0
--unity-colors-scrollbar_thumb-border The border color for a scrollbar’s thumb/handle #323232 #B9B9B9 transparent
--unity-colors-scrollbar_thumb-border-focus Undefined Undefined #00516A
--unity-colors-scrollbar_thumb-border-hover The border color for a scrollbar’s thumb/handle when the mouse pointer hovers over it #686868 #8E8E8E transparent
--unity-colors-scrollbar_thumb-border-pressed Undefined Undefined transparent
slider_groove
--unity-colors-slider_groove-background The background color for a slider’s groove (background) #5E5E5E #8F8F8F #7E7E7E
--unity-colors-slider_groove-background-disabled The background color for a slider’s groove when it is disabled #575757 #A4A4A4 #7E7E7E
--unity-colors-slider_groove-background-focus Undefined Undefined #7E7E7E
--unity-colors-slider_groove-background-hover Undefined Undefined #7E7E7E
--unity-colors-slider_groove-border Undefined Undefined #646464
slider_thumb
--unity-colors-slider_thumb-background The background color for a slider’s thumb/handle #999999 #616161 #F0F0F0
--unity-colors-slider_thumb-background-disabled The background color for a slider’s thumb/handle when it is disabled #666666 #9B9B9B #808080
--unity-colors-slider_thumb-background-focus Undefined Undefined #F0F0F0
--unity-colors-slider_thumb-background-hover The background color for a slider’s thumb/handle when the mouse pointer hovers over it #EAEAEA #4F4F4F #F0F0F0
--unity-colors-slider_thumb-border The border color for a slider’s thumb #999999 #616161 #646464
--unity-colors-slider_thumb-border-disabled The border color for a slider’s thumb when it is disabled #666666 #666666 #7E7E7E
--unity-colors-slider_thumb-border-focus Undefined Undefined #006AA6
--unity-colors-slider_thumb-border-hover Undefined Undefined #323232
slider_thumb_halo
--unity-colors-slider_thumb_halo-background The background color for a slider’s thumb halo rgba(16, 111, 205, 0.5019608) rgba(12, 108, 203, 0.5019608) rgba(12, 108, 203, 0.5019608)
tab
--unity-colors-tab-background The background color for an Editor window tab #353535 #B6B6B6 Undefined
--unity-colors-tab-background-checked The background color for an Editor window tab when it is selected #3C3C3C #CBCBCB Undefined
--unity-colors-tab-background-hover The background color for an Editor window tab when the mouse pointer hovers over it #303030 #B0B0B0 Undefined
--unity-colors-tab-text The text color for an Editor window tab #BDBDBD #090909 Undefined
toggle
--unity-colors-toggle-text-disabled Undefined Undefined #585858
toggle_checkmark
--unity-colors-toggle_checkmark-background Undefined Undefined #F0F0F0
--unity-colors-toggle_checkmark-background-disabled Undefined Undefined #959595
--unity-colors-toggle_checkmark-border Undefined Undefined #646464
--unity-colors-toggle_checkmark-border-disabled Undefined Undefined #7E7E7E
--unity-colors-toggle_checkmark-border-focus Undefined Undefined #006AA6
--unity-colors-toggle_checkmark-border-hover Undefined Undefined #323232
--unity-colors-toggle_checkmark-border-pressed Undefined Undefined #323232
toolbar
--unity-colors-toolbar-background The background color for a toolbar control #3C3C3C #CBCBCB Undefined
--unity-colors-toolbar-border The border color for a toolbar control #232323 #999999 Undefined
toolbar_button
--unity-colors-toolbar_button-background The background color for a toolbar button control #3C3C3C #CBCBCB Undefined
--unity-colors-toolbar_button-background-checked The background color for a toolbar button control when it is checked #505050 #EFEFEF Undefined
--unity-colors-toolbar_button-background-focus The background color for a toolbar button control when it has focus #464646 #C1C1C1 Undefined
--unity-colors-toolbar_button-background-hover The background color for a toolbar button control when the mouse pointer hovers over it #464646 #C1C1C1 Undefined
--unity-colors-toolbar_button-border The border color for a toolbar button control #232323 #999999 Undefined
--unity-colors-toolbar_button-text The text color for a toolbar button control #C4C4C4 #090909 Undefined
--unity-colors-toolbar_button-text-checked The text color for a toolbar button control when it is checked #C4C4C4 #090909 Undefined
--unity-colors-toolbar_button-text-hover The text color for a toolbar button control #BDBDBD #090909 Undefined
tooltip
--unity-colors-tooltip-background #373737 #DEDEDE Undefined
--unity-colors-tooltip-border #191919 #8A8A8A Undefined
visited_link
--unity-colors-visited_link-text The text color for visited links #FF00FF #AA00AA Undefined
warning
--unity-colors-warning-text The text color for warning messages #F4BC02 #333308 Undefined
window
--unity-colors-window-background The background color for a window #383838 #C8C8C8 Undefined
--unity-colors-window-border The border color for a window #242424 #939393 Undefined
--unity-colors-window-text The text color for a window #BDBDBD #090909 #1B1B1B
font
--unity-font-button-padding-bottom 1px 1px Undefined
--unity-font-button-padding-top 1px 1px Undefined
--unity-font-popup-padding-bottom 1px 1px Undefined
--unity-font-popup-padding-top 0 0 Undefined
--unity-font-standard-padding-bottom 0 0 Undefined
--unity-font-standard-padding-bottom-with-border 0 0 Undefined
icons
--unity-icons-arrow_left Builtin Skins/DarkSkin/Images/ArrowNavigationLeft.png Builtin Skins/LightSkin/Images/ArrowNavigationLeft.png Undefined
--unity-icons-arrow_right Builtin Skins/DarkSkin/Images/ArrowNavigationRight.png Builtin Skins/LightSkin/Images/ArrowNavigationRight.png Undefined
--unity-icons-clear UIPackageResources/Images/d_clear.png UIPackageResources/Images/clear.png Undefined
--unity-icons-color_picker UIPackageResources/Images/d_color_picker.png UIPackageResources/Images/color_picker.png Undefined
--unity-icons-console_entry_error Icons/d_console.erroricon.png Icons/console.erroricon.png Undefined
--unity-icons-console_entry_error_small Icons/d_console.erroricon.sml.png Icons/console.erroricon.sml.png Undefined
--unity-icons-console_entry_info Icons/d_console.infoicon.png Icons/console.infoicon.png Undefined
--unity-icons-console_entry_info_small Icons/d_console.infoicon.sml.png Icons/console.infoicon.sml.png Undefined
--unity-icons-console_entry_warn Icons/d_console.warnicon.png Icons/console.warnicon.png Undefined
--unity-icons-console_entry_warn_small Icons/d_console.warnicon.sml.png Icons/console.warnicon.sml.png Undefined
--unity-icons-dropdown UIPackageResources/Images/d_dropdown.png UIPackageResources/Images/dropdown.png Undefined
--unity-icons-dropdown_toggle UIPackageResources/Images/d_dropdown_toggle.png UIPackageResources/Images/dropdown_toggle.png Undefined
--unity-icons-foldout UIPackageResources/Images/d_IN_foldout.png UIPackageResources/Images/IN_foldout.png Undefined
--unity-icons-foldout-checked UIPackageResources/Images/d_IN_foldout_on.png UIPackageResources/Images/IN_foldout_on.png Undefined
--unity-icons-foldout-checked_focus UIPackageResources/Images/d_IN_foldout_focus_on.png UIPackageResources/Images/IN_foldout_focus_on.png Undefined
--unity-icons-foldout-checked_pressed UIPackageResources/Images/d_IN_foldout_act_on.png UIPackageResources/Images/IN_foldout_act_on.png Undefined
--unity-icons-foldout-focus UIPackageResources/Images/d_IN_foldout_focus.png UIPackageResources/Images/IN_foldout_focus.png Undefined
--unity-icons-foldout-pressed UIPackageResources/Images/d_IN_foldout_act.png UIPackageResources/Images/IN_foldout_act.png Undefined
--unity-icons-link Icons/d_UnLinked.png Icons/UnLinked.png Undefined
--unity-icons-link-checked Icons/d_Linked.png Icons/Linked.png Undefined
--unity-icons-lock Builtin Skins/DarkSkin/Images/IN LockButton.png Builtin Skins/LightSkin/Images/IN LockButton.png Undefined
--unity-icons-lock-checked Builtin Skins/DarkSkin/Images/IN LockButton on.png Builtin Skins/LightSkin/Images/IN LockButton on.png Undefined
--unity-icons-lock-checked_pressed Builtin Skins/DarkSkin/Images/IN LockButton on act.png Builtin Skins/LightSkin/Images/IN LockButton on act.png Undefined
--unity-icons-lock-pressed Builtin Skins/DarkSkin/Images/IN LockButton act.png Builtin Skins/LightSkin/Images/IN LockButton act.png Undefined
--unity-icons-minus UIPackageResources/Images/d_ol_minus.png UIPackageResources/Images/ol_minus.png Undefined
--unity-icons-minus-hover UIPackageResources/Images/d_ol_minus_act.png UIPackageResources/Images/ol_minus_act.png Undefined
--unity-icons-pane_options Builtin Skins/DarkSkin/Images/pane options.png Builtin Skins/LightSkin/Images/pane options.png Undefined
--unity-icons-picker UIPackageResources/Images/d_pick.png UIPackageResources/Images/pick.png Undefined
--unity-icons-plus UIPackageResources/Images/d_ol_plus.png UIPackageResources/Images/ol_plus.png Undefined
--unity-icons-plus-hover UIPackageResources/Images/d_ol_plus_act.png UIPackageResources/Images/ol_plus_act.png Undefined
--unity-icons-profiler_timeline_digdown_arrow Profiler/d_ProfilerTimelineDigDownArrow.png Profiler/ProfilerTimelineDigDownArrow.png Undefined
--unity-icons-profiler_timeline_rollup_arrow Profiler/d_ProfilerTimelineRollUpArrow.png Profiler/ProfilerTimelineRollUpArrow.png Undefined
--unity-icons-pulldown UIPackageResources/Images/d_dropdown.png UIPackageResources/Images/dropdown.png Undefined
--unity-icons-scroll_down UIPackageResources/Images/d_scrolldown.png UIPackageResources/Images/scrolldown.png Undefined
--unity-icons-scroll_left UIPackageResources/Images/d_scrollleft.png UIPackageResources/Images/scrollleft.png Undefined
--unity-icons-scroll_right UIPackageResources/Images/d_scrollright.png UIPackageResources/Images/scrollright.png Undefined
--unity-icons-scroll_up UIPackageResources/Images/d_scrollup.png UIPackageResources/Images/scrollup.png Undefined
--unity-icons-search UIPackageResources/Images/d_search_icon.png UIPackageResources/Images/search_icon.png Undefined
--unity-icons-search_menu UIPackageResources/Images/d_search_menu.png UIPackageResources/Images/search_menu.png Undefined
--unity-icons-shuriken_toggle-checked Builtin Skins/DarkSkin/Images/ShurikenToggleNormalOn.png Builtin Skins/LightSkin/Images/ShurikenToggleNormalOn.png Undefined
--unity-icons-shuriken_toggle-checked_focus Builtin Skins/DarkSkin/Images/ShurikenToggleFocusedOn.png Builtin Skins/LightSkin/Images/ShurikenToggleFocusedOn.png Undefined
--unity-icons-shuriken_toggle-checked_hover Builtin Skins/DarkSkin/Images/ShurikenToggleHoverOn.png Builtin Skins/LightSkin/Images/ShurikenToggleHoverOn.png Undefined
--unity-icons-shuriken_toggle_bg Builtin Skins/DarkSkin/Images/ShurikenToggleNormal.png Builtin Skins/LightSkin/Images/ShurikenToggleNormal.png Undefined
--unity-icons-shuriken_toggle_bg-focus Builtin Skins/DarkSkin/Images/ShurikenToggleFocused.png Builtin Skins/LightSkin/Images/ShurikenToggleFocused.png Undefined
--unity-icons-shuriken_toggle_bg-focus_mixed Builtin Skins/DarkSkin/Images/ShurikenToggleFocusedMixed.png Builtin Skins/LightSkin/Images/ShurikenToggleFocusedMixed.png Undefined
--unity-icons-shuriken_toggle_bg-hover Builtin Skins/DarkSkin/Images/ShurikenToggleHover.png Builtin Skins/LightSkin/Images/ShurikenToggleHover.png Undefined
--unity-icons-shuriken_toggle_bg-hover_mixed Builtin Skins/DarkSkin/Images/ShurikenToggleHoverMixed.png Builtin Skins/LightSkin/Images/ShurikenToggleHoverMixed.png Undefined
--unity-icons-shuriken_toggle_bg-mixed Builtin Skins/DarkSkin/Images/ShurikenToggleNormalMixed.png Builtin Skins/LightSkin/Images/ShurikenToggleNormalMixed.png Undefined
--unity-icons-toggle-checked UIPackageResources/Images/d_toggle_on.png UIPackageResources/Images/toggle_on.png Undefined
--unity-icons-toggle-checked_focus UIPackageResources/Images/d_toggle_on_focus.png UIPackageResources/Images/toggle_on_focus.png Undefined
--unity-icons-toggle-checked_hover UIPackageResources/Images/d_toggle_on_hover.png UIPackageResources/Images/toggle_on_hover.png Undefined
--unity-icons-toggle-focus_mixed UIPackageResources/Images/d_toggle_on_focus.png UIPackageResources/Images/toggle_on_focus.png Undefined
--unity-icons-toggle-hover_mixed UIPackageResources/Images/d_toggle_on_hover.png UIPackageResources/Images/toggle_on_hover.png Undefined
--unity-icons-toggle-mixed UIPackageResources/Images/d_toggle_on.png UIPackageResources/Images/toggle_on.png Undefined
--unity-icons-toggle_bg UIPackageResources/Images/d_toggle_bg.png UIPackageResources/Images/toggle_bg.png Undefined
--unity-icons-toggle_bg-focus UIPackageResources/Images/d_toggle_bg_focus.png UIPackageResources/Images/toggle_bg_focus.png Undefined
--unity-icons-toggle_bg-focus_mixed UIPackageResources/Images/d_toggle_mixed_bg_focus.png UIPackageResources/Images/toggle_mixed_bg_focus.png Undefined
--unity-icons-toggle_bg-hover UIPackageResources/Images/d_toggle_bg_hover.png UIPackageResources/Images/toggle_bg_hover.png Undefined
--unity-icons-toggle_bg-hover_mixed UIPackageResources/Images/d_toggle_mixed_bg_hover.png UIPackageResources/Images/toggle_mixed_bg_hover.png Undefined
--unity-icons-toggle_bg-mixed UIPackageResources/Images/d_toggle_mixed_bg.png UIPackageResources/Images/toggle_mixed_bg.png Undefined
--unity-icons-window_button_close Icons/d_winbtn_win_close.png Icons/winbtn_win_close.png Undefined
--unity-icons-window_button_max Icons/d_winbtn_win_max.png Icons/winbtn_win_max.png Undefined
--unity-icons-window_button_restore Icons/d_winbtn_win_restore.png Icons/winbtn_win_restore.png Undefined

Additional resources

Introduction to USS built-in variables
Apply styles in C# scripts