codesandbox.io: collapse header for larger editor by myfonj

/* ==UserStyle==
@name           codesandbox.io: collapse header for larger editor
@namespace      myfonj
@version        1.0.0
@description    Pull header and social buttons to side panel, expand on hover
@author         myf
@license        CC0
==/UserStyle== */

/*
https://greasyfork.org/en/scripts/441676/versions/new
*/

@-moz-document domain("codesandbox.io") {
 /* categorisation */
}
@-moz-document url-prefix("https://codesandbox.io/s/") {
 header:not(:hover):not(:focus-within) {
   width: 55px;
   overflow: hidden;
 }
 header:not(:hover):not(:focus-within) a[href="/dashboard"] {
  opacity: 0;
 }
 header {
  z-index: 100;
  position: fixed;
  right: auto;
  left: 0;
 }
 /* reclaim header space */
 nav[aria-label="Sandbox Navigation"] + div {
  top: 0 !important;
 }
 /* sweep social buttons to panel */
 nav[aria-label="Sandbox Navigation"] + div > .SplitPane > .Pane1 > [class*="elements__Container"] > :last-child {
  position: fixed;
  bottom: .33em; left: .33em;
  display: flex;
  flex-direction: column;
 }
 nav[aria-label="Sandbox Navigation"] + div > .SplitPane > .Pane1 > [class*="elements__Container"] > :last-child  > div {
  display: contents;
 }
}