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Dark Minimalistic Scrollbar

Customizable scrollbar for WebKit based browsers (Chrome, Opera).

Instalar como estilo de usuario¿?
Script recomendado por el autor

Puede que también te guste GreasyFork - Dark Theme.

Instalar como estilo de usuario 
/* ==UserStyle==
@name         Dark Minimalistic Scrollbar
@namespace    https://github.com/pabli24/DMScrollbar
@version      0.1.3
@description  Customizable scrollbar for WebKit based browsers (Chrome, Opera).
@author       Pabli
@license      CC-BY-SA-4.0
@homepageURL  https://github.com/pabli24/DMScrollbar
@supportURL   https://github.com/pabli24/DMScrollbar/issues
@preprocessor uso
@var color border "border" #484848
@var color bar "bar" #383838
@var color hover "hover" #282828
@var color active "active" #181818
@var color corner "corner" #383838
@var color bg "background" rgba(0,0,0,0)
@var number width "width (px)" [10,0,null,null,'px']
@var number b "border (px)" [2,0,null,null,'px']
@var number br "border-radius (px)" [10,0,null,null,'px']
==/UserStyle== */
@-moz-document regexp(".*") {
html::-webkit-scrollbar {
	width: /*[[width]]*/ !important;
	height: /*[[width]]*/ !important;
	max-width: /*[[width]]*/ !important;
	max-height: /*[[width]]*/ !important;
	min-width: /*[[width]]*/ !important;
	min-height: /*[[width]]*/ !important;
}
html::-webkit-scrollbar-thumb {
	background-color: /*[[bar]]*/ !important;
	border: /*[[b]]*/ solid /*[[border]]*/ !important;
	border-radius: /*[[br]]*/ !important;
}
html::-webkit-scrollbar-track {
	background-color: /*[[bg]]*/ !important;
}
html::-webkit-scrollbar-thumb:hover {
	background: /*[[hover]]*/ !important;
	border: /*[[b]]*/ solid /*[[border]]*/ !important;
}
html::-webkit-scrollbar-thumb:active {
	background: /*[[active]]*/ !important;
}
html::-webkit-scrollbar-corner {
	background: /*[[corner]]*/ !important;
}
}