Restore the old style of Wikipedia.

EnableOldStyle.userstyle.css

/* ==UserStyle==
@name           Wiki old style
@namespace      github.com/peyang-Celeron/OldWiki
@version        1.0.1
@description    Comebacks old wikipedia style,
@author         Peyang
==/UserStyle== */

@-moz-document regexp("https?://(www\\.)?ja\\.wikipedia\\.org/wiki/.+") {
    body > div, body > div > div > div, body > div > div > div > div {
        margin: 0 !important;
        max-width: unset !important;
    }
    
    .mw-page-container-inner{
        grid-template: min-content min-content min-content 1fr min-content / min-content 20px minmax(0,1fr);
        grid-template-areas: 'header header header'
        'sitenotice sitenotice sitenotice'
        'sidebar gutter content'
        'toc gutter content'
        'footer footer footer'
    }
    
    body > div {
        padding: 0 !important;
    }
    
    #content {
        padding: 24px !important;
        margin-left: 6px !important;
        margin-right: 0px !important;
    }
    
    #mw-panel {
        padding-right: 0px !important;
        margin-left: 0px !important;
        
        max-width: 164px !important;
    }
    
    .mw-body {
        border-top:  1px solid rgb(8, 75, 122);
        border-left: 1px solid rgb(8, 75, 122);
        margin: 22px !important;
        padding: 0px !important;
        margin-top: 0px !important;
    }
    
    
    #left-navigation {
        padding: 0 !important;
        margin-left: 0 !important;
    }
    
    .mw-article-toolbar-container {
        margin-left: 0 !important;
        margin-right: 0 !important;
        max-width: unset !important;
    }
    
    .mw-sidebar-action {
        visibility: hidden !important;
        height: 0px !important;
    }
    
    body > div > div > div > div > nav > div {
        margin-left: 0 !important;
    }
    
    #mw-panel-toc {
        margin-left: 5px !important;
         max-width: 160px !important;
        padding-left: 25px !important;
    }
    
    ::-webkit-scrollbar {
        width: 10px;
    }

    ::-webkit-scrollbar-track {
        background: #666;
    }

    ::-webkit-scrollbar-thumb {
        background: #333;
        border-radius: 5px;
    }

    ::-webkit-scrollbar-thumb:hover {
        background: #444;
    }
    
    .vector-layout-grid .mw-page-container-inner {
        grid-template-columns: unset;
    }
}