@charset "UTF-8";
* {
  box-sizing: border-box; }

body {
  padding: 0;
  margin: 0;
  font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: #444444; }

a {
  color: #0a6fd1;
  text-decoration: none; }
  a:hover {
    text-decoration: underline; }

.btn {
  display: inline-block;
  margin-bottom: 1rem;
  color: rgba(255, 255, 255, 0.7);
  background-color: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.2);
  border-style: solid;
  border-width: 1px;
  border-radius: 0.3rem;
  transition: color 0.2s, background-color 0.2s, border-color 0.2s; }
  .btn:hover {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    background-color: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.3); }
  .btn + .btn {
    margin-left: 1rem; }
  @media screen and (min-width: 64em) {
    .btn {
      padding: 0.75rem 1rem; } }
  @media screen and (min-width: 42em) and (max-width: 64em) {
    .btn {
      padding: 0.6rem 0.9rem;
      font-size: 0.9rem; } }
  @media screen and (max-width: 42em) {
    .btn {
      padding: 0.75rem;
      font-size: 0.9rem; } }
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  color: #444444;
  background-color: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid #dbe4f0; }
  @supports (backdrop-filter: blur(1px)) {
    .site-header {
      background-color: rgba(255, 255, 255, 0.78);
      backdrop-filter: saturate(180%) blur(10px);
      -webkit-backdrop-filter: saturate(180%) blur(10px); } }

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 82rem;
  margin: 0 auto;
  padding: 0.5rem 1rem; }
  @media screen and (min-width: 42em) and (max-width: 64em) {
    .site-header-inner {
      padding: 0.55rem 1.5rem; } }
  @media screen and (min-width: 64em) {
    .site-header-inner {
      padding: 0.6rem 2rem; } }
.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  min-width: 0;
  font-weight: 600;
  line-height: 1.2;
  color: #222629; }
  .site-brand:hover, .site-brand:focus {
    color: #0a6fd1;
    text-decoration: none; }

.site-brand-logo {
  flex: 0 0 auto;
  display: block;
  width: 1.85rem;
  height: 1.85rem;
  border-radius: 0.5rem; }

.site-brand-text {
  font-size: 1rem; }
  @media screen and (max-width: 42em) {
    .site-brand-text {
      font-size: 0.95rem; } }
.site-header-nav {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 0.5rem; }

.site-header-link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.3rem 0.75rem;
  font-size: 0.9rem;
  line-height: 1.5;
  color: #0084ff;
  background-color: #fff;
  border: 1px solid rgba(0, 132, 255, 0.35);
  border-radius: 999px;
  transition: color 0.2s, background-color 0.2s, border-color 0.2s; }
  .site-header-link:hover, .site-header-link:focus {
    color: #fff;
    background-color: #0084ff;
    border-color: #0084ff;
    text-decoration: none; }

.site-header-icon {
  width: 0.8em;
  height: 0.8em; }

.main-content {
  word-wrap: break-word;
  line-height: 1.75; }
  .main-content :first-child {
    margin-top: 0; }
  .main-content h1, .main-content h2, .main-content h3, .main-content h4, .main-content h5, .main-content h6, .main-content .book-crumb, .main-content table {
    line-height: 1.4; }
  @media screen and (min-width: 64em) {
    .main-content {
      max-width: 56rem;
      padding: 2rem 6rem;
      margin: 0 auto;
      font-size: 1rem; } }
  @media screen and (min-width: 42em) and (max-width: 64em) {
    .main-content {
      padding: 2rem 4rem;
      font-size: 1rem; } }
  @media screen and (max-width: 42em) {
    .main-content {
      padding: 2rem 1rem;
      font-size: 1rem;
      line-height: 1.7; } }
  .main-content img {
    max-width: 100%;
    display: block;
    margin-left: auto;
    margin-right: auto; }
  .main-content figure {
    text-align: center; }
  .main-content p:has(> img) + p:has(> a:only-child):not(:has(> .fig-ref)),
  .main-content p:has(> a > img) + p:has(> a:only-child):not(:has(> .fig-ref)),
  .main-content p:has(> picture > img) + p:has(> a:only-child):not(:has(> .fig-ref)),
  .main-content a:has(> img) + p:has(> a:only-child):not(:has(> .fig-ref)),
  .main-content a:has(> picture > img) + p:has(> a:only-child):not(:has(> .fig-ref)),
  .main-content figure + p:has(> a:only-child):not(:has(> .fig-ref)) {
    text-align: center;
    text-indent: 0; }
  .main-content figure + p {
    text-align: left;
    text-indent: 2em; }
  .main-content figure.fig-block {
    display: block;
    margin: 1.75rem auto;
    text-indent: 0; }
  .main-content figure.fig-block img {
    display: block;
    margin: 0 auto; }
  .main-content figure.fig-block figcaption {
    margin-top: 0.6rem;
    font-size: 0.9rem;
    line-height: 1.6;
    font-weight: 400;
    text-align: center;
    text-indent: 0;
    color: #819198; }
  .main-content figure.fig-block figcaption .fig-num {
    font-weight: 600;
    color: inherit; }
  .main-content .fig-ref {
    white-space: nowrap;
    color: inherit; }
  .main-content .fig-ref-missing {
    color: #819198; }
  .main-content .footnote-ref {
    text-decoration: none; }
  .main-content .footnotes {
    margin-top: 2.5rem;
    font-size: 0.9rem;
    line-height: 1.7;
    color: #819198; }
    .main-content .footnotes hr {
      margin: 1.5rem 0 1rem;
      height: 1px;
      background-color: #dbe4f0; }
    .main-content .footnotes ol {
      padding-left: 1.4rem; }
    .main-content .footnotes li p {
      text-indent: 0; }
  .main-content .footnote-backref {
    text-decoration: none; }
  .main-content h1,
  .main-content h2,
  .main-content h3,
  .main-content h4,
  .main-content h5,
  .main-content h6 {
    margin-top: 2rem;
    margin-bottom: 1rem;
    font-weight: normal;
    color: #0a6fd1; }
  .main-content p {
    margin-bottom: 1.5em;
    text-indent: 2em; }
  .main-content p:has(> img),
  .main-content p:has(> picture),
  .main-content p:has(> a > img),
  .main-content p:has(> a > picture),
  .main-content p:has(> center),
  .main-content p.blog-notice,
  .main-content .blog-promo p,
  .main-content blockquote p,
  .main-content li p,
  .main-content td p,
  .main-content p:empty {
    text-indent: 0; }
  .main-content code {
    padding: 2px 4px;
    font-family: Consolas, "Liberation Mono", Menlo, Courier, monospace;
    font-size: 0.9em;
    color: #567482;
    background-color: #f2f6fb;
    border-radius: 0.3rem; }
  .main-content pre {
    padding: 0.8rem;
    margin-top: 0;
    margin-bottom: 1rem;
    font: 1rem Consolas, "Liberation Mono", Menlo, Courier, monospace;
    color: #567482;
    word-wrap: normal;
    background-color: #f2f6fb;
    border: solid 1px #dbe4f0;
    border-radius: 0.3rem; }
    .main-content pre > code {
      padding: 0;
      margin: 0;
      font-size: 0.9rem;
      color: #567482;
      word-break: normal;
      white-space: pre;
      background: transparent;
      border: 0; }
  .main-content .highlight {
    margin-bottom: 1rem; }
    .main-content .highlight pre {
      margin-bottom: 0;
      word-break: normal; }
  .main-content .highlight pre,
  .main-content pre {
    padding: 0.8rem;
    overflow: auto;
    font-size: 0.9rem;
    line-height: 1.45;
    border-radius: 0.3rem;
    -webkit-overflow-scrolling: touch; }
  .main-content pre code,
  .main-content pre tt {
    display: inline;
    max-width: initial;
    padding: 0;
    margin: 0;
    overflow: initial;
    line-height: inherit;
    word-wrap: normal;
    background-color: transparent;
    border: 0; }
    .main-content pre code:before, .main-content pre code:after,
    .main-content pre tt:before,
    .main-content pre tt:after {
      content: normal; }
  .main-content ul,
  .main-content ol {
    margin-top: 0; }
  .main-content blockquote {
    padding: 0 1rem;
    margin-left: 0;
    color: #819198;
    border-left: 0.3rem solid #dbe4f0; }
    .main-content blockquote > :first-child {
      margin-top: 0; }
    .main-content blockquote > :last-child {
      margin-bottom: 0; }
  .main-content blockquote.alert {
    padding: 1rem 1.25rem;
    margin: 1.75rem 0;
    color: #444444;
    background-color: rgba(10, 111, 209, 0.07);
    border: 1px solid rgba(10, 111, 209, 0.35);
    border-left-width: 0.8rem;
    border-left-color: #0a6fd1;
    border-radius: 0 0.4rem 0.4rem 0;
    box-shadow: 0.15rem 0.2rem 0.45rem rgba(0, 0, 0, 0.12);
    font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, "Kaiti SC", "STKaiti", "KaiTi", "KaiTi_GB2312", "楷体", "AR PL UKai CN", "WenQuanYi Micro Hei", serif;
    font-size: 0.95em; }
  .main-content blockquote.alert .alert-title {
    margin-bottom: 0.75rem;
    font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, "Heiti SC", "STHeiti", "SimHei", "黑体", "WenQuanYi Micro Hei", "Microsoft YaHei", sans-serif;
    font-weight: 600;
    text-indent: 0; }
  .main-content blockquote.alert p {
    text-indent: 2em; }
  .main-content blockquote.alert-note {
    background-color: rgba(10, 111, 209, 0.07);
    border: 1px solid rgba(10, 111, 209, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(10, 111, 209, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #0a6fd1;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-info {
    background-color: rgba(43, 127, 212, 0.07);
    border: 1px solid rgba(43, 127, 212, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(43, 127, 212, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #2b7fd4;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-tip {
    background-color: rgba(15, 157, 143, 0.07);
    border: 1px solid rgba(15, 157, 143, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(15, 157, 143, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #0f9d8f;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-important {
    background-color: rgba(107, 91, 210, 0.07);
    border: 1px solid rgba(107, 91, 210, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(107, 91, 210, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #6b5bd2;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-question {
    background-color: rgba(217, 138, 0, 0.07);
    border: 1px solid rgba(217, 138, 0, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(217, 138, 0, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #d98a00;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-success {
    background-color: rgba(31, 156, 111, 0.07);
    border: 1px solid rgba(31, 156, 111, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(31, 156, 111, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #1f9c6f;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-warning {
    background-color: rgba(199, 119, 0, 0.07);
    border: 1px solid rgba(199, 119, 0, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(199, 119, 0, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #c77700;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-failure {
    background-color: rgba(176, 64, 64, 0.07);
    border: 1px solid rgba(176, 64, 64, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(176, 64, 64, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #b04040;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-danger {
    background-color: rgba(209, 67, 67, 0.07);
    border: 1px solid rgba(209, 67, 67, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(209, 67, 67, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #d14343;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-bug {
    background-color: rgba(194, 53, 107, 0.07);
    border: 1px solid rgba(194, 53, 107, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(194, 53, 107, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #c2356b;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-example {
    background-color: rgba(58, 110, 165, 0.07);
    border: 1px solid rgba(58, 110, 165, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(58, 110, 165, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #3a6ea5;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-quote {
    background-color: rgba(107, 114, 128, 0.07);
    border: 1px solid rgba(107, 114, 128, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(107, 114, 128, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #6b7280;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-abstract {
    background-color: rgba(91, 122, 153, 0.07);
    border: 1px solid rgba(91, 122, 153, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(91, 122, 153, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #5b7a99;
    border-radius: 0.3rem; }
  .main-content blockquote.alert-todo {
    background-color: rgba(138, 123, 47, 0.07);
    border: 1px solid rgba(138, 123, 47, 0.35);
    border-radius: 0.4rem;
    background-color: #fff;
    border: 1px solid rgba(138, 123, 47, 0.55);
    border-left-width: 0.25rem;
    border-left-color: #8a7b2f;
    border-radius: 0.3rem; }
  .main-content table {
    display: block;
    margin: 0 auto;
    width: 90%;
    overflow: auto;
    word-break: normal;
    word-break: keep-all;
    -webkit-overflow-scrolling: touch; }
    .main-content table th {
      font-weight: bold;
      width: 100%; }
    .main-content table th,
    .main-content table td {
      padding: 0.5rem 1rem;
      border: 1px solid #e9ebec; }
  .main-content dl {
    padding: 0; }
    .main-content dl dt {
      padding: 0;
      margin-top: 1rem;
      font-size: 1rem;
      font-weight: bold; }
    .main-content dl dd {
      padding: 0;
      margin-bottom: 1rem; }
  .main-content hr {
    height: 2px;
    padding: 0;
    margin: 3rem 0;
    background-color: #eff0f1;
    border: 0; }

.site-footer {
  padding-top: 2rem;
  margin-top: 2rem;
  border-top: solid 1px #eff0f1;
  align-content: center;
  text-align: center;
  color: #41484c; }
  @media screen and (min-width: 64em) {
    .site-footer {
      font-size: 0.9rem; } }
  @media screen and (min-width: 42em) and (max-width: 64em) {
    .site-footer {
      font-size: 0.9rem; } }
  @media screen and (max-width: 42em) {
    .site-footer {
      font-size: 0.4rem; } }
.site-footer-owner {
  display: block;
  font-weight: bold; }

.site-footer-credits {
  color: #819198; }

.site-footer .logo {
  cursor: default;
  margin: 0;
  padding: 0; }

.site-footer .logo img {
  width: 2.5em;
  display: inline-block;
  line-height: 1em;
  border-left: solid 1px rgba(128, 128, 128, 0.35);
  padding: 0 0 0 0.5em;
  margin: 0 0 0 0.5em;
  vertical-align: middle; }

.site-footer .logo img:first-child {
  width: 2em;
  border-left: 0;
  padding-left: 0;
  margin-left: 0; }

.page-404 {
  padding: 1rem 0 0;
  text-align: center; }
  .page-404 .page-404-code {
    margin-bottom: 0.5rem;
    font-size: 6rem;
    font-weight: 700;
    line-height: 1;
    letter-spacing: 0.08em;
    color: #0a6fd1; }
  .page-404 .page-404-title {
    margin: 0 0 1.5rem;
    font-size: 1.6rem;
    font-weight: normal;
    color: #0a6fd1; }
  .page-404 .page-404-desc {
    max-width: 34rem;
    margin: 0 auto 0.75rem;
    color: #444444; }
  .page-404 .page-404-actions {
    margin: 2.25rem 0 1.75rem; }
  .page-404 .page-404-btn {
    display: inline-block;
    margin: 0.3rem 0.35rem;
    padding: 0.6rem 1.25rem;
    font-size: 0.95rem;
    color: #0a6fd1;
    background-color: #fff;
    border: 1px solid #0a6fd1;
    border-radius: 0.3rem;
    transition: color 0.2s, background-color 0.2s, border-color 0.2s; }
    .page-404 .page-404-btn:hover {
      color: #fff;
      background-color: #0a6fd1;
      text-decoration: none; }
  .page-404 .page-404-btn--primary {
    color: #fff;
    background-color: #0a6fd1;
    background-image: linear-gradient(120deg, #222629, #0a6fd1);
    border-color: transparent; }
    .page-404 .page-404-btn--primary:hover {
      color: #fff;
      background-color: #0a6fd1;
      background-image: linear-gradient(120deg, #0a6fd1, #222629); }
  .page-404 .page-404-hint {
    max-width: 34rem;
    margin: 0 auto;
    font-size: 0.85rem;
    line-height: 1.7;
    color: #819198; }
  @media screen and (max-width: 42em) {
    .page-404 .page-404-code {
      font-size: 4rem; }
    .page-404 .page-404-title {
      font-size: 1.35rem; }
    .page-404 .page-404-btn {
      display: block;
      max-width: 14rem;
      margin: 0.5rem auto; } }
@media screen and (min-width: 70em) {
  .main-content.main-content-wide {
    max-width: 68rem;
    padding: 2rem 3rem; } }

@media screen and (min-width: 42em) and (max-width: 64em) {
  .main-content.main-content-wide {
    padding: 2rem 2.5rem; } }

@media screen and (min-width: 90em) {
  .main-content.main-content-wide {
    max-width: 72rem; } }

@media screen and (min-width: 112em) {
  .main-content.main-content-wide {
    max-width: 74rem;
    padding: 2rem 4rem; } }

.book-layout,
.blog-layout {
  display: flex;
  align-items: flex-start;
  gap: 2rem; }
  @media screen and (min-width: 112em) {
    .book-layout,
    .blog-layout {
      gap: 2.5rem; } }
  @media screen and (max-width: 70em) {
    .book-layout,
    .blog-layout {
      display: block; } }
@media screen and (min-width: 70em) {
  .book-sidebar,
  .blog-sidebar {
    flex: 0 0 15rem;
    width: 15rem;
    position: sticky;
    top: 4rem;
    max-height: calc(100vh - 5.5rem);
    overflow-y: auto; } }

@media screen and (min-width: 90em) {
  .book-sidebar,
  .blog-sidebar {
    flex-basis: 16rem;
    width: 16rem; } }

@media screen and (min-width: 112em) {
  .book-sidebar,
  .blog-sidebar {
    flex-basis: 17rem;
    width: 17rem; } }

@media screen and (max-width: 70em) {
  .book-sidebar,
  .blog-sidebar {
    width: 100%;
    margin-bottom: 1.5rem; } }

.book-body,
.blog-body {
  flex: 1 1 auto;
  min-width: 0;
  max-width: 72rem; }
  .book-body > :first-child,
  .blog-body > :first-child {
    margin-top: 0; }

.blog-notice {
  margin-top: 2em;
  margin-bottom: 2em;
  padding: 0.7rem 0.9rem;
  font-size: 0.95rem;
  text-indent: 0;
  background-color: rgba(10, 111, 209, 0.07);
  border: 1px solid rgba(10, 111, 209, 0.35);
  border-left-width: 0.8rem;
  border-left-color: #0a6fd1;
  border-radius: 0 0.4rem 0.4rem 0;
  box-shadow: 0.15rem 0.2rem 0.45rem rgba(0, 0, 0, 0.12);
  font-family: "Open Sans", "Helvetica Neue", Helvetica, Arial, "Kaiti SC", "STKaiti", "KaiTi", "KaiTi_GB2312", "楷体", "AR PL UKai CN", "WenQuanYi Micro Hei", serif; }

.blog-promo {
  width: 100%;
  margin-top: 50px;
  padding-top: 5px;
  border-top: 2px solid #0a6fd1; }

.book-crumb {
  margin-bottom: 0.5rem;
  font-size: 0.85rem;
  color: #819198;
  text-indent: 0; }

.book-crumb-sep {
  margin: 0 0.4rem; }

.book-toc,
.blog-toc {
  padding: 1rem;
  background-color: #fff;
  border: 1px solid #dbe4f0;
  border-radius: 0.3rem; }
  @media screen and (max-width: 70em) {
    .book-toc,
    .blog-toc {
      max-height: 16rem;
      overflow-y: auto; } }
.book-toc-book,
.blog-toc-book {
  font-weight: 600; }
  .book-toc-book a,
  .blog-toc-book a {
    color: #0a6fd1; }
  .book-toc-book .book-toc-desc,
  .book-toc-book .blog-toc-desc,
  .blog-toc-book .book-toc-desc,
  .blog-toc-book .blog-toc-desc {
    display: block;
    margin-top: 0.2rem;
    font-weight: 400;
    font-size: 0.85rem;
    line-height: 1.4;
    color: #819198; }
  .book-toc-book::after,
  .blog-toc-book::after {
    content: "";
    display: block;
    width: calc(100% - 2rem);
    height: 1px;
    margin: 0.85rem auto 00.85rem;
    background-color: #dbe4f0; }

.book-toc-list,
.blog-toc-list {
  margin: 1.15rem 0 0;
  padding-left: 0;
  list-style: none;
  font-size: 0.95rem; }

.book-toc-item,
.blog-toc-item {
  margin: 0.15rem 0; }
  .book-toc-item a,
  .blog-toc-item a {
    display: block;
    padding: 0.4rem 0.55rem;
    color: #444444;
    border-radius: 0.25rem; }
    .book-toc-item a:hover,
    .blog-toc-item a:hover {
      color: #0a6fd1;
      text-decoration: none;
      background-color: #f2f6fb; }

.book-toc-num {
  margin-right: 0.35rem;
  color: #819198;
  font-variant-numeric: tabular-nums; }

.blog-toc-count {
  float: right;
  margin-left: 0.5rem;
  color: #819198;
  font-size: 0.85em;
  font-variant-numeric: tabular-nums; }

.book-toc-item.book-toc-current > a,
.book-toc-item.book-toc-current > a:hover,
.blog-toc-item.blog-toc-current > a,
.blog-toc-item.blog-toc-current > a:hover {
  color: #fff;
  background-color: #0a6fd1; }
  .book-toc-item.book-toc-current > a .book-toc-num,
  .book-toc-item.book-toc-current > a .blog-toc-count,
  .book-toc-item.book-toc-current > a:hover .book-toc-num,
  .book-toc-item.book-toc-current > a:hover .blog-toc-count,
  .blog-toc-item.blog-toc-current > a .book-toc-num,
  .blog-toc-item.blog-toc-current > a .blog-toc-count,
  .blog-toc-item.blog-toc-current > a:hover .book-toc-num,
  .blog-toc-item.blog-toc-current > a:hover .blog-toc-count {
    color: rgba(255, 255, 255, 0.75); }

.book-comments {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid #dbe4f0; }

.book-toc-empty,
.blog-toc-empty {
  text-indent: 0;
  margin: 0.75rem 0 0;
  font-size: 0.9rem;
  color: #819198; }

.book-hero {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  margin-bottom: 1.5rem; }
  @media screen and (max-width: 42em) {
    .book-hero {
      display: block; } }
.main-content .book-hero-cover {
  display: block;
  width: 9rem;
  margin: 0;
  border: 1px solid #dbe4f0;
  border-radius: 0.3rem; }
  @media screen and (max-width: 42em) {
    .main-content .book-hero-cover {
      margin: 0 auto 1rem; } }
.book-hero-body {
  flex: 1 1 auto;
  min-width: 0; }
  .book-hero-body h1 {
    margin-top: 0; }

.book-hero-desc {
  color: #819198; }

.book-meta {
  margin: 0;
  padding-left: 0;
  list-style: none;
  font-size: 0.9rem;
  color: #819198; }
  .book-meta li {
    display: inline-block;
    margin-right: 1rem; }

.book-section-title {
  margin-top: 2.5rem; }

.book-chapters {
  padding-left: 0;
  list-style: none; }

.book-chapter {
  border-bottom: 1px solid #eff0f1; }
  .book-chapter a {
    display: block;
    padding: 0.6rem 0.25rem; }
  .book-chapter a:hover .book-chapter-title {
    color: #0a6fd1; }

.book-chapter-num {
  margin-right: 0.5rem;
  color: #819198;
  font-variant-numeric: tabular-nums; }

.book-chapter-title {
  color: #0a6fd1; }

.book-empty {
  color: #819198; }

.item > a.item-link,
.item > a.item-link:hover,
.item > a.item-link:focus {
  display: block;
  border-bottom: 0;
  color: inherit;
  text-decoration: none;
  cursor: pointer; }