CONTENTS OF firefox.css
:root {
  --0: #1E2A2B;
  --1: #C57750;
  --2: #788871;
  --3: #AE8D6C;
  --4: #CC936A;
  --5: #C3AF9E;
  --6: #CEB09E;
  --7: #E3CFCA;
  --8: #666666;
  --9: #C57750;
  --10: #788871;
  --11: #AE8D6C;
  --12: #CC936A;
  --13: #C3AF9E;
  --14: #CEB09E;
  --15: #E3CFCA;
}


CONTENTS of userChrome.css

@import url(firefox.css);
#toolbar-menubar,
findbar {
    z-index: 2!important;
    position: fixed!important
}
findbar {
    height: 43px!important
}
#main-menubar {
    height: 46px !important
}
#notification-popup-box,
.findbar-button,
.findbar-button *,
.tabbrowser-tab * {
    -moz-appearance: none!important
}
#nav-bar,
#urlbar,
.ac-action,
.ac-title,
.ac-title[selected=true],
.ac-url {
    color: var(--grey)!important
}
@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);
:root {
    --bg: var(--0);
    --grey: var(--8);
    --main: var(--9);
    --secondary: var(--10);
    --main-tab-height: 4px
}
* {
    outline: 0!important
}
#menubar-items,
#urlbar,
.downloadDetails,
.downloadTarget,
.menubar-text,
.textbox-input-box,
[class*=menu],
findbar,
menu {
    font-family: Hack, "Open Sans", sans-serif!important
}
#main-menubar {
    margin-top: -1px!important;
    padding-right: 1450px!important;
    margin-bottom: -1px!important
}
#toolbar-menubar {
    background-color: var(--bg)!important
}
findbar {
    top: 3px !important;
    padding-right: 1300px!important;
    padding-top: 2px!important;
    border: none!important
}
.findbar-textbox.findbar-find-fast {
    border-radius: 0!important;
    border: none!important;
    margin-top: -1px!important
}
.findbar-button:hover,
.findbar-button[checked=true] {
    background-color: var(--main)!important
}
.findbar-button[checked=true]:hover {
    background-color: var(--secondary)!important
}
browser {
    background: url(bg) center no-repeat!important
}
tooltip {
    padding: 3px 6px!important
}
#PanelUI-menu-button,
#PopupAutoCompleteRichResult,
#TabsToolbar::after,
#back-button .toolbarbutton-icon,
#context-back,
#context-bookmarklink,
#context-bookmarkpage,
#context-copyvideo,
#context-cut,
#context-delete,
#context-forward,
#context-openlink,
#context-openlinkprivate,
#context-reload,
#context-savelink,
#context-selectall,
#context-sendimage,
#context-sendvideo,
#context-sep-bidi,
#context-sep-copyimage,
#context-sep-copylink,
#context-sep-navigation,
#context-sep-open,
#context-sep-paste,
#context-sep-properties,
#context-sep-selectall,
#context-sep-stop,
#context-sep-undo,
#context-sep-viewbgimage,
#context-sep-viewsource,
#context-undo,
#forward-button .toolbarbutton-icon,
#frame-sep,
#identity-box,
#liberator-separator,
#plugins-notification-icon,
#private-browsing-indicator,
#searchbar .search-go-button,
#searchbar .searchbar-dropmarker-image,
#sidebar-search-container,
#urlbar dropmarker,
#urlbar>toolbarbutton,
.ac-separator,
.autocomplete-history-popup,
.findbar-closebutton,
.findbar-find-next,
.findbar-find-previous,
.notificationbox-stack,
.statuspanel-label,
.tab-background-end,
.tab-background-start,
.tab-throbber,
.tab-throbber[progress],
.tabbrowser-arrowscrollbox+stack,
.tabbrowser-arrowscrollbox>.scrollbutton-down,
.tabbrowser-arrowscrollbox>.scrollbutton-up,
.tabbrowser-tab .tab-text,
.tabbrowser-tab:not([pinned]) .tab-icon-image,
.tabbrowser-tab:not([pinned]):hover .tab-close-button:before,
.tabs-border-bottom,
.tabs-closebutton-box,
.tabs-newtab-button,
menuseperator,
panel[type=autocomplete]:not([type=arrow]),
panel[type=autocomplete-richlistbox]:not([type=arrow]),
statuspanel,
toolbarbutton#alltabs-button,
toolbarbutton#appmenu-toolbar-button,
toolbarbutton#new-tab-button {
    display: none!important
}
#forward-button {
    margin-left: -30px!important
}
#notification-popup-box {
    background: 0 0!important;
    box-shadow: none!important;
    border-image: none!important;
    border: 0;
    list-style-image: none
}
#PanelUI-button {
    border-image: none!important;
    border: rgba(0, 0, 0, .15)!important
}
#browser-bottombox {
    border: none!important;
    background: 0 0!important;
    border-bottom: 0 solid!important
}
#browser-border-end,
#browser-border-start {
    background: 0 0!important;
    border-left: 0 solid!important
}
#nav-bar,
#urlbar,
.tabbrowser-tab {
    background: var(--bg)!important
}
#nav-bar {
    padding: 5px 0!important;
    box-shadow: none!important;
    display: moz-box!important
}
#main-window[sizemode=maximized] #nav-bar,
#main-window[sizemode=normal]:not([inFullscreen]) #nav-bar {
    border-radius: 0!important
}
#urlbar {
    height: 30px!important;
    text-align: center!important;
    margin-bottom: 2px!important;
    margin-left: 77px!important;
    margin-right: 6px!important;
    border-top: 0 solid!important;
    border-bottom: 0 solid!important;
    border-left: 0 solid!important;
    border-right: 0 solid!important;
    font-weight: 700!important
}
#urlbar * {
    border: none!important
}
.ac-title {
    font-size: 16px!important
}
tabs#tabbrowser-tabs,
tabs#tabbrowser-tabs * {
    -moz-appearance: none!important;
    border-radius: 0!important;
    border: none!important;
    border-bottom: none!important;
    margin-top: 0!important;
    margin-bottom: 0!important;
    max-height: var(--main-tab-height)!important;
    min-height: var(--main-tab-height)!important;
    z-index: 0!important
}
.tabbrowser-tab {
    margin-left: 0!important;
    margin-right: -5px!important
}
.tabbrowser-tab[selected=true] {
    background: var(--grey)!important;
    box-shadow: none!important
}
.tabbrowser-tab *,
.tabbrowser-tab::after,
.tabbrowser-tab::before {
    background: 0 0!important
}
.tabbrowser-tabs:not([drag=detach])>.tabbrowser-tab:not([pinned])[fadein] {
    min-width: 30px!important;
    max-width: 100%!important
}
#navigator-toolbox {
    border: 0!important;
    margin-bottom: -1px!important
}
.tabbrowser-tab * {
    list-style-image: none!important;
    margin: 0!important;
    padding: 0!important
}
#tabbrowser-tabs .arrowscrollbox-scrollbox {
    background: var(--bg)!important;
    margin-right: -10px
}
#TabsToolbar {
    margin-left: -15px!important;
    -moz-box-ordinal-group: 2!important
}
#alltabs-button,
#customToolbars,
#new-tab-button,
#noscript-tbb,
#window-controls {
    background: var(--bg)!important;
    box-shadow: none!important;
    border: none!important
}
.tabbrowser-tab .tab-close-button:before {
    display: none;
    content: '×';
    color: var(--grey)!important;
    position: absolute;
    top: 10px;
    right: 4px
}
#contentAreaContextMenu image,
#placesContext image,
.textbox-contextmenu image {
    visibility: hidden!important
}