style.css

/* slightly adapted from https://codepen.io/dredmorbius/pen/KpMqqB */
html {
  font-size: 22px;
}

body {
  background-color: #fffff6;
  color: #330;
  font-family: georgia, times, serif;
  margin: 2rem auto 8rem;
  max-width: 40em;
  padding: 0 2em;
  width: auto;
  font-size: 1rem;
  line-height: 1.4;
}

a {
  color: #1e6b8c;
  font-size: 1em;
  text-decoration: none;
  transition-delay: 0.1s;
  transition-duration: 0.3s;
  transition-property: color, background-color;
  transition-timing-function: linear;
}

a:visited {
  color: #6f32ad;
  font-size: 1em;
}

a:hover {
  background: #f0f0ff;
  font-size: 1em;
  text-decoration: underline;
}

a:active {
  background-color: #427fed;
  color: #fffff6;
  color: white;
  font-size: 1em;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  color: #703820;
  font-weight: bold;
  line-height: 1.2;
  margin-bottom: 1em;
  margin-top: 2em;
}

h1 {
  font-size: 1.45em;
  text-align: center;
}

h2 {
  font-size: 1.6em;
  border-bottom: solid 0.1rem #703820;
}

h3 {
  font-size: 1.5em;
}

h4 {
  font-size: 1.3em;
  text-decoration: underline;
}

h5 {
  font-size: 1.2em;
  font-style: italic;
}

h6 {
  font-size: 1.1em;
  margin-bottom: 0.5rem;
  color: #330;
}

pre,
code,
xmp {
  font-family: courier;
  font-size: 1.1rem;
  line-height: 1.4;
  white-space: pre-wrap;
}

img {
  margin: 2em auto;
  padding: 1em;
  outline: solid 1px #ccc;
  max-width: 90%;
}

/* smooth scroll */
html {
  scroll-behavior: smooth;
}
/* table of contents */
#toc {
  position: fixed;
  left: 2em;
  top: 2em;
  font-size: 0.9em;
  max-width: 30em;
}

#github {
  position: absolute;
  right: 2em;
  top: 2em;
}