body {
    max-width: 900px;
    margin: 40px auto;
    padding: 0 20px;
    font-family: -apple-system, BlinkMacSystemFont,
                 "Segoe UI", Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #24292f;
}

h1, h2, h3 {
    margin-top: 1.5em;
    line-height: 1.25;
}

h1 {
    border-bottom: 1px solid #d0d7de;
    padding-bottom: 0.3em;
}

h2 {
    border-bottom: 1px solid #d8dee4;
    padding-bottom: 0.25em;
}

pre {
    background: #f6f8fa;
    padding: 16px;
    border-radius: 6px;
    overflow-x: auto;
}

code {
    background: #f6f8fa;
    padding: 0.15em 0.3em;
    border-radius: 4px;
}

pre code {
    padding: 0;
}

table {
    border-collapse: collapse;
    width: 100%;
}

th, td {
    border: 1px solid #d0d7de;
    padding: 6px 13px;
}

th {
    background: #f6f8fa;
}

blockquote {
    border-left: 4px solid #d0d7de;
    padding-left: 1em;
    color: #57606a;
}

img {
    max-width: 100%;
}

/* ----------------------------------------------------------
   Lecture navigation
   ---------------------------------------------------------- */

.lecture-nav {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    width: 100%;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border);
}

.lecture-nav .home {
    justify-self: center;
}

.lecture-nav .next {
    justify-self: end;
}