style.css

@import url('https://fonts.googleapis.com/css2?family=Bree+Serif&family=Source+Serif+4&display=swap');

div.proof>*:last-child:after {
  color: red;

}
div.theorem, div.definition {
  margin: 10px;
  background-color: #eee;
  border-radius: 3px;
  padding: 5px;
}

a.navigation-prev, a.navigation-next {
  color: #F00E4D!important;
}
.level1 h1 {
  border-bottom: 1px solid #F00E4D;
}
.toc-logo img {
  max-width: 90%;
}
.header-section-number {
  text-align: center;
  padding-left: 5px;
  border-bottom: 5px solid #F00E4D;
  display: inline-block;
}
p, div {
  font-family: 'Source Serif 4', sans-serif!important;
}
.book-summary {
  line-height:0.5em;
}
h1, h2, h3, h4, h5, h6 {
  font-family: 'Bree Serif', serif;
}
li.active > a {
  background-color:  rgba(240, 14, 77, 0.1)!important;
  color: #F00E4D!important;
  border-right: 5px solid #F00E4D;
}
li > a:hover {
  color: #F00E4D!important;
}

.header-section-number {
  color: #F00E4D;
}
p.caption {
  color: #777;
  margin-top: 10px;
}
p code {
  white-space: inherit;
}
pre {
  word-break: normal;
  word-wrap: normal;
}
pre code {
  white-space: inherit;
}