userChrome.css

/* Custom min-max-close Buttons */
.titlebar-button {
	transition: all 0.3s ease !important;
	padding: 8px 10px !important;
    
}
.titlebar-button > .toolbarbutton-icon {
	transition: all 0.3s ease !important;
	list-style-image: none;
  border: 1px solid;
	border-radius: 10px;
}
.titlebar-button.titlebar-min > .toolbarbutton-icon {
	background: #27c840 !important;
  border-color: #27c83f7a !important;
}

.titlebar-button.titlebar-max > .toolbarbutton-icon,
.titlebar-button.titlebar-restore > .toolbarbutton-icon {
	background: #febb2e !important;
  border-color: #febc2e7c !important;
}

.titlebar-button.titlebar-close > .toolbarbutton-icon {
	background: #ff5f57 !important;
	stroke: #ff5f57 !important;
  border-color: #ff5f5777 !important;
  
}
.titlebar-button.titlebar-close:hover > .toolbarbutton-icon {
	background: #ff5f5742 !important;
  border: 1px solid;
  border-color: #ff5f57 !important;
}
.titlebar-button.titlebar-close:hover {
	background: #fdfdfd00 !important;
}
.titlebar-button.titlebar-max:hover > .toolbarbutton-icon,
.titlebar-button.titlebar-restore:hover > .toolbarbutton-icon {
	background: #febc2e44 !important;
  border: 1px solid;
  border-color: #febb2e !important;
}
.titlebar-button.titlebar-max:hover, .titlebar-button.titlebar-restore:hover {
	background: #fdfdfd00 !important;
}
.titlebar-button.titlebar-min:hover > .toolbarbutton-icon {
	background: #27c83f38 !important;
  border: 1px solid;
  border-color: #27c840 !important;
}
.titlebar-button.titlebar-min:hover {
	background: #1d1d1d00 !important;
}

/* Custom tab active color */
.tab-background[selected="true"] {
  background: #424df1 !important;
} 

/* rework of container line
.tab-context-line{margin-top: 1px !important; max-height: 1px !important; }
.tab-context-line{-moz-box-ordinal-group: 1 !important; opacity: 1 !important;transition: none !important;}
*/

/* Glowing line at top. */
.tabbrowser-tab > .tab-stack > .tab-background > .tab-context-line
{
	background-color: var(--identity-icon-color) !important;
	height: 1px !important;
	border-radius: 1px !important;
	margin: var(--tab-border-radius) var(--tab-border-radius) 0px !important;
	box-shadow: 0px 3px 9px 0px var(--identity-icon-color) !important;
  
}
.tabbrowser-tab > .tab-stack > .tab-background
{
    border-width: 0px !important;
}
/* URLBar*/
#urlbar:not([focused="true"]) > #urlbar-background {
  border-radius: 5px;
	background: #ffffff15 !important;
  box-shadow: 0px 0px 4px 0px hsla(240,5%,5%,0.3) !important;
}
#urlbar[open] > #urlbar-background{
  border: none !important;
  box-shadow: 0px 0px 4px 0px rgb(12, 12, 13) !important;
}

#urlbar {
	text-align: center !important;
}
/* Source below from https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/autohide_bookmarks_and_main_toolbars.css */
/* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/autohide_bookmarks_and_main_toolbars.css made available under Mozilla Public License v. 2.0
See the above repository for updates as well as full license text. */

#navigator-toolbox{
  --uc-bm-padding: 4px; /* Vertical padding to be applied to bookmarks */
  --uc-bm-height: calc(20px + 2 * var(--uc-bm-padding)); /* Might need to adjust if the toolbar has other buttons */
  --uc-navbar-height: -40px; /* navbar is main toolbar. Use negative value */
  --uc-autohide-toolbar-delay: 600ms; /* The toolbar is hidden after 0.6s */
}



:root[uidensity="compact"] #navigator-toolbox{
  --uc-bm-padding: 1px;
  --uc-navbar-height: -34px;
}
:root[uidensity="touch"] #navigator-toolbox{ --uc-bm-padding: 6px }

:root[sessionrestored] #nav-bar,
:root[sessionrestored] #PersonalToolbar{
  background-image: linear-gradient(var(--toolbar-bgcolor),var(--toolbar-bgcolor)), var(--lwt-additional-images,var(--toolbar-bgimage))  !important;
  background-position: top,var(--lwt-background-alignment);
  background-position-y: calc(0px - var(--tab-min-height) - 2*var(--tab-block-margin,0px));
  background-repeat: repeat,var(--lwt-background-tiling);
  transform: rotateX(90deg);
  transform-origin: top;
  transition: transform 135ms linear var(--uc-autohide-toolbar-delay) !important;
  z-index: 2;
}

:root[sessionrestored] #PersonalToolbar{
  z-index: 1;
  background-position-y: calc(0px - var(--tab-min-height) - 2*var(--tab-block-margin,0px) + var( --uc-navbar-height));
}

:root[lwtheme-image] #nav-bar,
:root[lwtheme-image] #PersonalToolbar{
  background-image: linear-gradient(var(--toolbar-bgcolor),var(--toolbar-bgcolor)),var(--lwt-header-image), var(--lwt-additional-images,var(--toolbar-bgimage)) !important;
}

#nav-bar[customizing],#PersonalToolbar[customizing]{ transform: none !important }

#navigator-toolbox > #PersonalToolbar{
  transform-origin: 0px var(--uc-navbar-height);
  position: relative;
}

:root[sessionrestored]:not([customizing]) #navigator-toolbox{
  margin-bottom:  calc(0px - var(--uc-bm-height) + var(--uc-navbar-height));
}
#PlacesToolbarItems > .bookmark-item {
  min-height: calc(var(--uc-bm-height) - 4px); /* Bookmarks have 2px block margin */
  padding-block: 0px !important;
}

#OtherBookmarks,
#PlacesChevron,
#PersonalToolbar > #import-button{
  padding-block: var(--uc-bm-padding) !important;
}

/* Make sure the bookmarks toolbar is never collapsed even if it is disabled */
:root[sizemode="fullscreen"] #PersonalToolbar,
#PersonalToolbar[collapsed="true"]{
  min-height: initial !important;
  max-height: initial !important;
  visibility: hidden !important
}
#PersonalToolbar[collapsed="true"] #PlacesToolbarItems > *,
:root[sizemode="fullscreen"] #PersonalToolbar #PlacesToolbarItems > *{
  visibility: hidden !important;
}

/* The invisible toolbox will overlap sidebar so we'll work around that here */
#navigator-toolbox{ pointer-events: none; border-bottom: none !important; }
#PersonalToolbar{ border-bottom: 1px solid var(--chrome-content-separator-color) }
#navigator-toolbox > *{ pointer-events: auto }

#sidebar-box{ position: relative }

/* Selected tab needs higher z-index now to "hide" the broder below it */
.tabbrowser-tab[selected]{ z-index: 3 !important; }

/* SELECT TOOLBAR BEHAVIOR */
/* Comment out or delete one of these to disable that behavior */

/* Show when urlbar is focused */
#nav-bar:focus-within + #PersonalToolbar,
#navigator-toolbox > #nav-bar:focus-within{
  transition-delay: 100ms !important;
  transform: rotateX(0);
}

/* Show when cursor is over the toolbar area */
#navigator-toolbox:hover > .browser-toolbar{
  transition-delay: 100ms !important;
  transform: rotateX(0);
}
/* This makes the tab notification box show immediately below tabs, otherwise it would break the layout */
#navigator-toolbox > div{ display: contents }
:where(#titlebar,#tab-notification-deck,.global-notificationbox){
  -moz-box-ordinal-group: 0;
}
/* Show when cursor is over popups/context-menus - cannot control which ones */
/*
#mainPopupSet:hover ~ box > toolbox > .browser-toolbar{
  transition-delay: 100ms !important;
  transform: rotateX(0);
}
*/

/* Uncomment the next part to enable compatibility for multi-row_bookmarks.css
 * This would break buttons placed in the toolbar,
 * but that is likely not happening if you are using multi-row setup
 */
 
/*
#navigator-toolbox{ margin-bottom: var(--uc-navbar-height) !important; }
#PersonalToolbar:not([customizing]){
  position: fixed !important;
  display: block;
  margin-bottom: 0px !important;
}
*/