/* ===== reset ===== */
* {
    font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
    color: #3a3a3a;
}

ul,
li {
    list-style: none;
    padding: 0;
    margin: 0;
}

li {
    text-indent: -1em;
    transform: translateX(1em);
}

li:before {
    content: "-";
    margin-right: 0.5em;
    letter-spacing: 0;
}

/* ===== markdown ===== */
body {
    max-width: 800px;
    margin: 2rem auto;
    font-family: sans-serif;
    line-height: 1.7;
    padding: 0 1rem;
}

pre {
    background: #f6f8fa;
    padding: 1rem;
    overflow-x: auto;
    border-radius: 4px;
}

code {
    background: #f6f8fa;
    padding: .2em .4em;
    border-radius: 3px;
    font-size: .9em;
}

pre code {
    background: none;
    padding: 0;
}

blockquote {
    border-left: 4px solid #ddd;
    margin: 0;
    padding-left: 1rem;
    color: #555;
}

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

th,
td {
    border: 1px solid #ddd;
    padding: .5rem .75rem;
}

th {
    background: #f6f8fa;
}

img {
    max-width: 100%;
}

/* ===== parts ===== */

header {
    display: flex;
    padding: 0.8em;
    line-height: 3em;
    letter-spacing: 3px;
}

header ul {
    display: flex;
    gap: 0 2em;
    flex-wrap: wrap;
}

@media (width < 950px) {
    header ul {
        flex-direction: column;
    }
}

header ul li {
    white-space: nowrap;
}

footer {
    text-align: center;
    padding: 0.8em;
    line-height: 3em;
    letter-spacing: 3px;
}

main {
    max-width: 800px;
    margin: 0 auto;
    padding: 0.8em;
    line-height: 2em;
    letter-spacing: 1px;
}

/* ===== top page ===== */
.index h1 {
    text-align: center;
}

.top__main {
    height: 100%;
    text-align: center;
    line-height: 3em;
    letter-spacing: 3px;
}

.top__main h1 {
    white-space: nowrap;
}

.top__main .table-of-contents ul {
    text-align: left;
}


/* ===== article ===== */
article {
    border-top: 1px solid #8d8d8d;
    padding: 1em 0;
}

article pre {
    line-height: 1.5em;
    overflow-x: scroll;
    background-color: #fbfbfb;
    padding: 0 1em;
}

canvas {
    position: fixed;
    top: 0;
    left: 0;

    width: 100%;
    height: auto;

    pointer-events: none;
    z-index: -1;
}

.toc {
    margin: 2em 0;
    width: calc(100% - 2em);
}

.toc ol {
    display: flex;
    flex-direction: column;
}