:root { /* Only applies adaptive colour if tab is not empty */ &:has(#tabbrowser-tabpanels > .browserSidebarContainer[id] browser:not([transparent])) { –zen-main-browser-background: var(--lwt-accent-color) !important; } /* Reverts toolbar button’s active colour */ –toolbarbutton-active-background: var(--zen-toolbar-element-bg) !important; } /* Removes shadow around the tab panel & side bar */ .browserSidebarContainer, #zen-tabbox-wrapper #sidebar-box { box-shadow: none !important; } /* Removes tab outline */ .tab-background { outline: none !important; } /* Makes tab panel transparent */ browser[transparent="true"] { background-color: transparent !important; }