For Firefox. Hides distracting StackExchange "Hot Network Questions"; changes Google Docs background color from snowblindness white to a more palatable gray

userContent.css

@-moz-document domain(stackexchange.com), domain(stackoverflow.com), domain(serverfault.com) {
    #hot-network-questions {
        display: none;
    }
}

@-moz-document domain(docs.google.com) {
    /* Background area behind the document page */
    .kix-appview {
        background-color: slategray !important;
    }

    /* Make Google Docs gray background instead of intense snowblindness white */
    /* Right nav */ .companion-guest-app-switcher, .companion-collapser-button-container
    {
        background-color: Gainsboro;
    }
    /* Blank page area at end of document; excluding selected text */ .kix-paginateddocumentplugin > .docs-ui-unprintable, 
    /* Left nav */ .navigation-widget, 
    /* Main document page */ .kix-page, .kix-page-column,
    /* Title and top menu */ #docs-chrome, .docs-title-input,
    /* Top toolbar */ #docs-toolbar-wrapper, 
    /* Top-right-corner nav */ .docs-titlebar-buttons
    {
        background-color: Gainsboro !important;
    }
    /* Toolbar buttons */
    .goog-toolbar-button, .goog-toolbar-menu-button, .goog-toolbar-combo-button
    {
        background-color: lightgray !important;
    }
    /* Toolbar button group separator lines */
    .goog-toolbar-separator
    {
        border-left-color: silver !important;
    }
}