It's the commodore64 template but in a red-dark style.

dark64.css

/*
TO DO YOUR OWN TEMPLATES
YOU MUST ONLY MODIFY THE LINES WITH A COMMENT
 */
:root{
 --color:#990000;
 --color2:#000;
 --background:#000;
 --highlight:#FF9900;
 --link:#33FF33;
}
*{
 font-family: C64R, monospace;
 font-size:1.6vmax;
 border:0px;
}
html,body{
 background:#990000;
 overflow: hidden;
}
a{
 background:rgba(0,0,0,0);
 border-top:0.16em dotted #33FF33;
 border-bottom:0.16em dotted #33FF33;
 border-right:none;
 border-left:none;
}
a:hover{
 background:#33FF33;
 color:#FFF;
 border-top:0.16em dotted #FFF;
 border-bottom:0.16em dotted #FFF;
}
label{
 color:#FFF;
}
label:not(.dis):hover{
 background:var(--highlight);
}
#corp{
 background:var(--background);
 margin:64px 64px 64px 64px;
 width:calc(100vw - 128px);
 height:calc(100vh - 128px);
 overflow-x: hidden;
 overflow-y: scroll;
}
span.pret::before{content:"";} /* THE "PRETEXT" */
@media only screen and (max-width: 512px) {
 *{font-size:12pt;}
 #corp{
 margin:8vh 8vw 8vh 8vw;
 width:calc(100vw - 16vw);
 height:calc(100vh - 16vh);
 }
}