style.css

body {
    font: 16px/1.5 'Roboto Slab', sans-serif;
    color: #444;
    width: 850px;
    margin: 30px auto 0;
}

a {
    color: #666666;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

header {
    position: relative;
    margin: 50px 0 10px;
}

img.logo {
    float: left;
    margin: 50px 0 0 0;
}

div.content {
    overflow: auto;
}

h1 {
    font-size: 30px;
    font-family: 'Roboto Slab', sans-serif;
    text-transform: uppercase;
    margin: 0 0 5px 0;
}

h2 {
    font-size: 26px;
    font-family: 'Convergence', sans-serif;
    text-transform: uppercase;
    margin: 0 0 5px 0;
}

h2.nocaps {
    text-transform: none;
}

h1.title {
    font-size: 72px;
    text-align: right;
    line-height: 1.25;
    color: #646464;
    text-transform: none;
    margin: 0;
}

h2.subtitle {
    font-size: 15px;
    text-align: right;
    color: #666666;
}

nav {
    position: absolute;
    top: -45px;
    right: 0;
}

nav li {
    float: left;
}

nav li a {
    margin: 0 10px;
}

nav li:last-child a {
    margin-right: 0;
}

.buttons {
    float: right;
}

pre {
    padding: 15px 20px;
    font-family: monaco, monospace;
    font-size: 14px;
    background: #eee;
}

strong {
    font-weight: bold;
}

footer {
    padding: 15px 0 20px;
    font-size: 14px;
    color: #999;
    border-top: 2px solid #ddd;
    margin-top: 20px;
}

.right {
    float: right;
}

.left {
    float: left;
}

.spon-logo {
    display: block;
    float: left;
    width: 250px;
    padding: 20px;
    padding-left: 0;
}

.spon-logo-dark {
    display: none;
}

.spon-text {
    /*display: block;*/
    float: left;
    /*padding-left: 12px;*/
    width: 460px;
}

.window {
  width: calc(100% - 10px);
  border-radius: 0.5rem;
  box-shadow: 6px 6px 5px rgba(0, 0, 0, 0.5);
  overflow: hidden;
}
.window .window-header {
  height: 37px;
  background: Gainsboro;
  position: relative;
}
.window .window-header .action-buttons {
  position: absolute;
  top: 50%;
  left: 10px;
  margin-top: -5px;
  width: 10px;
  height: 10px;
  background: Crimson;
  border-radius: 50%;
  box-shadow: 15px 0 0 Orange,
				30px 0 0 LimeGreen;
}

summary {
  height: 37px;
  background: Gainsboro;
  position: relative;
}

summary .file-name {
  position: relative;
  top: 50%;
  transform: translateY(-50%);
  left: 10px;
  margin-right: 10px;
}

details summary .file-name::after{
    content: "Click to expand";
    float: right;
    margin-right: 10px;
}

details[open] summary .file-name::after{
    content: "Click to collapse";
}

/* Hide the "▶" button */
/* https://stackoverflow.com/a/66814239/10606962 */
details > summary {
  list-style: none;
}
details > summary::marker, /* Latest Chrome, Edge, Firefox */
details > summary::-webkit-details-marker /* Safari */ {
  display: none;
}