Help to tailor theme for Unix

[Rosmaninho]

*\zotero\chrome\content\zotero-platform\unix\overlay.css

Play with these settings:

/*
 Override selected, unfocused tree row highlight color, which is too similar to the alternating
 row color by default
*/
#zotero-collections-tree treechildren::-moz-tree-row(selected),
#zotero-items-tree treechildren::-moz-tree-row(selected) {
    background-color: #D4D4D4;
}

#zotero-collections-tree treechildren::-moz-tree-row(selected, focus),
#zotero-items-tree treechildren::-moz-tree-row(selected, focus) {
    background-color: Highlight;
}

#zotero-collections-tree treechildren::-moz-tree-row {
    height: 1.3em;
}

@media (min-resolution: 1.25dppx) {
    #zotero-pane .toolbarbutton-icon {
        width: 16px;
    }

    #zotero-tb-sync > .toolbarbutton-icon {
        width: 20px;
    }
}

/* Dropmarker added automatically on Linux */
.toolbarbutton-menu-dropmarker, #zotero-tb-search-menu-button {
    list-style-image: none;
}

.zotero-tb-button:not([type=menu]) {
    margin-right: 4px;
}

#zotero-tb-search-menu-button {
    -moz-appearance: toolbarbutton-dropdown !important;
    width: 12px;
    height: 12px;
}

#zotero-tb-search-menu-button .button-menu-dropmarker {
    display: none;
}

#zotero-tb-search .textbox-search-icon {
    visibility: hidden;
}

/* Fixes tabs missing styling on (GTK 3.20) Ubuntu 16.10. See https://bugzilla.mozilla.org/show_bug.cgi?id=1306425 */
tabpanels {
    -moz-appearance: none;
    border: 1px solid hsla(0, 0%, 0%, 0.2);

}
tab {
    -moz-appearance: none;
    border-top: 1px solid hsla(0, 0%, 0%, 0.2);
    border-right: 1px solid hsla(0, 0%, 0%, 0.2);
    border-left: 1px solid hsla(0, 0%, 0%, 0.2);
}
/* Fixes misc Ubuntu 16.10 rendering issue fixes. */
#zotero-prefs menulist dropmarker{
    width: 30px;
}
#zotero-prefs .numberbox-input-box{
    -moz-appearance: textfield;
}

#zotero-pane splitter {
    border: 0;
    width: 6px;
    background-color: transparent;
    background-image: none;
}

[Rosmaninho]

*\zotero\chrome\content\zotero-platform\unix\integration.css

body {
    line-height: 1.5em;
}

#quick-format-search:not([multiline="true"]) {
    height: 29px !important;
}

#quick-format-search {
    background: white;
    padding: 0 2px 0 0;
    border: 1px solid rgba(0, 0, 0, 0.5);
    -moz-appearance: textfield;
}

#quick-format-dialog {
    -moz-appearance: none;
    padding: 5px;
}

#zotero-icon {
    margin: 0 0 0 2px;
    -moz-appearance: none;
}

[Rosmaninho]

"C:\Users\aesousa\Downloads\zotero\chrome\content\zotero-platform\unix\itemPane.css"

/* Some distros have icons disabled by default at the OS level and
 * mozilla is a respectful gent.
 */
#zotero-feed-item-addTo-button .button-icon {
    display: block;
    margin-right: 5px
}

/* Set to hidden in user-agent css for some reason. */
#zotero-feed-item-addTo-button .menu-iconic-left {
    visibility: visible;
}

#zotero-item-pane-content {
    margin-right: 6px;
}

/* Make the item pane appear white (same colour as treeview), making the UI more consistent */
#zotero-item-pane-content tab, #zotero-item-pane-content tabpanels {
    background-color: -moz-Field; /* Same as background colour for treeview */
}

/* Possibly irrelevant if mozilla fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1306425 */
#zotero-view-tabbox tabs tab[visuallyselected=true] {
    margin-top: 0px !important; /* Importanter than ./itemPane.css:20 */
    margin-bottom: -2px !important; /* Importanter than skin/itemPane.css:12 */
}
#zotero-view-tabbox tabs tab {
    margin-top: 2px !important; /* Importanter than skin/itemPane.css:11 */
}

[ghost]

Just tried installing the theme on Linux (Manjaro), it kind of works. Zotero booted successfully and some of the colors were applied correctly. The messiest part was the menu bar, though. Could be possible to tailor it so it's usable on Linux and Mac, too.