Hastebin

/* Navigation toolbar (bar below tabs) */
#nav-bar {
    background-color: #000000 !important;
    box-shadow: none !important; /* Removes separator line */
}

/* Tab text color */
.tab-label {
    color: #ffffff !important;
}

/* URL Bar - Inactive (default) */
#urlbar,
#urlbar-input-container,
#urlbar-background {
    background-color: #101010 !important;
    color: #ffffff !important;
    border-color: #444444 !important; /* Gray border replaces blue */
}

/* URL Bar - Active (focused) */
#urlbar[focused],
#urlbar[focused] #urlbar-input-container,
#urlbar[focused] #urlbar-background {
    background-color: #111111 !important;
    color: #ffffff !important;
    border-color: #444444 !important; /* Gray border when focused */
}

/* URL Bar dropdown suggestion box */
.urlbarView {
    background-color: #111111 !important; /* Matches active URL bar */
    border-color: #444444 !important;
}

/* URL Bar dropdown items */
.urlbarView-row {
    background-color: transparent !important;
}

.urlbarView-row[selected] {
    background-color: #444444 !important; /* Slightly lighter gray for selected item */
}

/* Search bar (optional, matches URL bar) */
.searchbar-textbox {
    background-color: #101010 !important;
    color: #ffffff !important;
    border-color: #444444 !important;
}

.searchbar-textbox[focused] {
    background-color: #111111 !important;
    border-color: #444444 !important;
}

.tabbrowser-tab:nth-of-type(4n+0){--bgcolor: #0078ff}
.tabbrowser-tab:nth-of-type(4n+1){--bgcolor: #bd00ff}
.tabbrowser-tab:nth-of-type(4n+2){--bgcolor: #ff9a00}
.tabbrowser-tab:nth-of-type(4n+3){--bgcolor: #01ff1f}
.tabbrowser-tab:nth-of-type(4n+4){--bgcolor: #e3ff00}

.tab-context-line{
	border-radius: 5px !important;
	translate: -5px 10px !important;
	margin: 0 100px 0 5px !important;
	width: 50% !important;
	height: 13px !important;
	filter: blur(13px) !important;
	overflow: visible !important;
	z-index: 10 !important;
	background-color: var(--bgcolor);
	position: relative;
}