.column_half {
    display: inline-block;
    width: 50%;
    vertical-align: top;
}

.centered_container {
    display: flex;
    flex-wrap: nowrap;
    align-items: center;
    justify-content: space-around;
}

.centered_container > * {
    flex-basis: auto;
    flex-grow: 0;
    flex-shrink: 1;
}

code {
    border-radius: 4px;
}
main pre code.hljs {
    padding: 0.6em; /* override hljs padding */
}

hr {
    border-top-width: 2px;
    border-bottom-width: 0px;
    border-color: #7f7f7f7f;
}

/* === highlightjs code === */
:not(pre) > code.hljs {
    background-color: #e0e0e0;
}

.hljs-ln-n {
    border: none;
    padding: 0.1em 0.5em;
}

ol ol {
    list-style: lower-alpha;
}

ol ol ol {
    list-style: lower-roman;
}