body, html {
    background-color: #5f6875;
    color: #dfeaf1;
    font-family: 'Courier New', Courier, monospace;
    margin: 0;
}
main {
    display: flex;
}
section {
    flex-grow: 1;
    margin: 1em;
    display: flex;
    flex-direction: column;
}
section .entry {
    flex-grow: 1;
}
aside {
    flex: 0 0;
    min-width: 13rem;
    border-right: 1px solid #ffffff3d;
    padding: 1em;
}
.io {
    background-color: #c3c3c3;
    border: 0.3em solid transparent;
    box-sizing: border-box;
    color: black;
    display: block;
    font-family: inherit;
    font-size: inherit;
    padding: 1em;
    width: 100%;
}
aside .io {
    padding: 0.5em;
}
.entry:hover {
    background-color: #d6d6d6;
}
.entry:focus {
    background-color: white;
    outline: none;
}
textarea {
    resize: vertical;
    height: 15vh;
}
textarea.error {
    border-color: #ffbdbd;
}
.error {
    background-color: #ffbdbd;
    color: red;
}
h1, h2, h3 {
    font-family: Tahoma, Geneva, sans-serif;
    font-weight: lighter;
}
h1 {
    font-size: 3em;
    margin: 0.3em;
}
h2 {
    font-size: 1.5em;
}
h3 {
    font-size: 1.2em;
}
a {
    color: inherit;
}
footer {
    text-align: center;
}
footer ul {
    padding: 0;
}
footer li {
    display: inline;
}
footer li + li::before {
    content: '| ';
}