@charset "UTF-8";
:root {
  --gray-100: #f8f9fa;
  --gray-200: #e9ecef;
  --gray-500: #adb5bd;
  --color-link: #0055bb;
  --color-visited-link: #8440f1;
  --body-background: white;
  --body-font-color: black;
  --icon-filter: none;
  --hint-color-info: #6bf;
  --hint-color-warning: #fd6;
  --hint-color-danger: #f66;
} /*!normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css*/
html {
  line-height: 1.15;
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
}
main {
  display: block;
}
h1 {
  font-size: 2em;
  margin: 0.67em 0;
}
hr {
  box-sizing: content-box;
  height: 0;
  overflow: visible;
}
pre {
  font-family: monospace, monospace;
  font-size: 1em;
}
a {
  background-color: transparent;
}
abbr[title] {
  border-bottom: none;
  text-decoration: underline;
  text-decoration: underline dotted;
}
b,
strong {
  font-weight: bolder;
}
code,
kbd,
samp {
  font-family: monospace, monospace;
  font-size: 1em;
}
small {
  font-size: 80%;
}
sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}
sub {
  bottom: -0.25em;
}
sup {
  top: -0.5em;
}
img {
  border-style: none;
}
button,
input,
optgroup,
select,
textarea {
  font-family: inherit;
  font-size: 100%;
  line-height: 1.15;
  margin: 0;
}
button,
input {
  overflow: visible;
}
button,
select {
  text-transform: none;
}
button,
[type='button'],
[type='reset'],
[type='submit'] {
  -webkit-appearance: button;
}
button::-moz-focus-inner,
[type='button']::-moz-focus-inner,
[type='reset']::-moz-focus-inner,
[type='submit']::-moz-focus-inner {
  border-style: none;
  padding: 0;
}
button:-moz-focusring,
[type='button']:-moz-focusring,
[type='reset']:-moz-focusring,
[type='submit']:-moz-focusring {
  outline: 1px dotted ButtonText;
}
fieldset {
  padding: 0.35em 0.75em 0.625em;
}
legend {
  box-sizing: border-box;
  color: inherit;
  display: table;
  max-width: 100%;
  padding: 0;
  white-space: normal;
}
progress {
  vertical-align: baseline;
}
textarea {
  overflow: auto;
}
[type='checkbox'],
[type='radio'] {
  box-sizing: border-box;
  padding: 0;
}
[type='number']::-webkit-inner-spin-button,
[type='number']::-webkit-outer-spin-button {
  height: auto;
}
[type='search'] {
  -webkit-appearance: textfield;
  outline-offset: -2px;
}
[type='search']::-webkit-search-decoration {
  -webkit-appearance: none;
}
::-webkit-file-upload-button {
  -webkit-appearance: button;
  font: inherit;
}
details {
  display: block;
}
summary {
  display: list-item;
}
template {
  display: none;
}
[hidden] {
  display: none;
}
.flex {
  display: flex;
}
.flex-auto {
  flex: auto;
}
.flex-even {
  flex: 1 1;
}
.flex-wrap {
  flex-wrap: wrap;
}
.justify-start {
  justify-content: flex-start;
}
.justify-end {
  justify-content: flex-end;
}
.justify-center {
  justify-content: center;
}
.justify-between {
  justify-content: space-between;
}
.align-center {
  align-items: center;
}
.mx-auto {
  margin: 0 auto;
}
.text-center {
  text-align: center;
}
.text-left {
  text-align: left;
}
.text-right {
  text-align: right;
}
.hidden {
  display: none;
}
input.toggle {
  height: 0;
  width: 0;
  overflow: hidden;
  opacity: 0;
  position: absolute;
}
.clearfix::after {
  content: '';
  display: table;
  clear: both;
}
html {
  font-size: 16px;
  scroll-behavior: smooth;
  touch-action: manipulation;
}
body {
  min-width: 20rem;
  color: var(--body-font-color);
  background: var(--body-background);
  letter-spacing: 0.33px;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  box-sizing: border-box;
}
body * {
  box-sizing: inherit;
}
h1,
h2,
h3,
h4,
h5 {
  font-weight: 400;
}
a {
  text-decoration: none;
  color: var(--color-link);
}
img {
  vertical-align: baseline;
}
:focus {
  outline-style: auto;
  outline-color: currentColor;
  outline-color: -webkit-focus-ring-color;
}
aside nav ul {
  padding: 0;
  margin: 0;
  list-style: none;
}
aside nav ul li {
  margin: 1em 0;
  position: relative;
}
aside nav ul a {
  display: block;
}
aside nav ul a:hover {
  opacity: 0.5;
}
aside nav ul ul {
  padding-inline-start: 1rem;
}
ul.pagination {
  display: flex;
  justify-content: center;
  list-style-type: none;
  padding-inline-start: 0;
}
ul.pagination .page-item a {
  padding: 1rem;
}
.container1 {
  max-width: 80rem;
  margin: 0 auto;
}
.book-icon {
  filter: var(--icon-filter);
}
.book-brand {
  margin-top: 0;
  margin-bottom: 1rem;
}
.book-brand img {
  height: 1.5em;
  width: 1.5em;
  margin-inline-end: 0.5rem;
}
.book-menu {
  flex: 0 0 16rem;
  font-size: 0.875rem;
}
.book-menu .book-menu-content {
  width: 16rem;
  padding: 1rem;
  background: var(--body-background);
  position: fixed;
  top: 100px;
  bottom: 0;
  overflow-x: hidden;
  overflow-y: auto;
}
.book-menu a,
.book-menu label {
  color: inherit;
  cursor: pointer;
  word-wrap: break-word;
}
.book-menu a.active {
  color: var(--color-link);
}
.book-menu input.toggle + label + ul {
  display: none;
}
.book-menu input.toggle:checked + label + ul {
  display: block;
}
.book-menu input.toggle + label::after {
  content: '▸';
}
.book-menu input.toggle:checked + label::after {
  content: '▾';
}
body[dir='rtl'] .book-menu input.toggle + label::after {
  content: '◂';
}
body[dir='rtl'] .book-menu input.toggle:checked + label::after {
  content: '▾';
}
.book-section-flat {
  margin: 2rem 0;
}
.book-section-flat > a,
.book-section-flat > span,
.book-section-flat > label {
  font-weight: bolder;
}
.book-section-flat > ul {
  padding-inline-start: 0;
}
.book-page {
  min-width: 20rem;
  flex-grow: 1;
  padding: 1rem;
}
.book-post {
  margin-bottom: 3rem;
}
.book-header {
  display: none;
  margin-bottom: 1rem;
}
.book-header label {
  line-height: 0;
}
.book-header img.book-icon {
  height: 1.5em;
  width: 1.5em;
}
.book-search {
  position: relative;
  margin: 1rem 0;
  border-bottom: 1px solid transparent;
}
.book-search input {
  width: 100%;
  padding: 0.5rem;
  border: 0;
  border-radius: 0.25rem;
  background: var(--gray-100);
  color: var(--body-font-color);
}
.book-search input:required + .book-search-spinner {
  display: block;
}
.book-search .book-search-spinner {
  position: absolute;
  top: 0;
  margin: 0.5rem;
  margin-inline-start: calc(100% - 1.5rem);
  width: 1rem;
  height: 1rem;
  border: 1px solid transparent;
  border-top-color: var(--body-font-color);
  border-radius: 50%;
  animation: spin 1s ease infinite;
}
@keyframes spin {
  100% {
    transform: rotate(360deg);
  }
}
.book-search small {
  opacity: 0.5;
}
.book-toc {
  flex: 0 0 16rem;
  font-size: 0.75rem;
}
.book-toc .book-toc-content {
  width: 16rem;
  padding: 1rem;
  position: fixed;
  top: 90px;
  bottom: 0;
  overflow-x: hidden;
  overflow-y: auto;
}
.book-toc .book-toc-content nav {
  margin-top: -1rem;
}
.book-toc img {
  height: 1em;
  width: 1em;
}
.book-toc nav > ul > li:first-child {
  margin-top: 0;
}
.book-footer {
  padding-top: 1rem;
  font-size: 0.875rem;
}
.book-footer img {
  height: 1em;
  width: 1em;
  margin-inline-end: 0.5rem;
}
.book-comments {
  margin-top: 1rem;
}
.book-languages {
  margin-block-end: 2rem;
}
.book-languages .book-icon {
  height: 1em;
  width: 1em;
  margin-inline-end: 0.5em;
}
.book-languages ul {
  padding-inline-start: 1.5em;
}
.book-menu-content,
.book-toc-content,
.book-page,
.book-header aside,
.markdown {
  transition: 0.2s ease-in-out;
  transition-property: transform, margin, opacity, visibility;
  will-change: transform, margin, opacity;
}
@media screen and (max-width: 56rem) {
  #menu-control,
  #toc-control {
    display: inline;
  }
  .book-menu {
    visibility: hidden;
    margin-inline-start: -16rem;
    font-size: 16px;
    z-index: 1;
  }
  .book-toc {
    display: none;
  }
  .book-header {
    display: block;
  }
  #menu-control:focus ~ main label[for='menu-control'] {
    outline-style: auto;
    outline-color: currentColor;
    outline-color: -webkit-focus-ring-color;
  }
  #menu-control:checked ~ main .book-menu {
    visibility: initial;
  }
  #menu-control:checked ~ main .book-menu .book-menu-content {
    transform: translateX(16rem);
    box-shadow: 0 0 0.5rem rgba(0, 0, 0, 0.1);
  }
  #menu-control:checked ~ main .book-page {
    opacity: 0.25;
  }
  #menu-control:checked ~ main .book-menu-overlay {
    display: block;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
  }
  #toc-control:focus ~ main label[for='toc-control'] {
    outline-style: auto;
    outline-color: currentColor;
    outline-color: -webkit-focus-ring-color;
  }
  #toc-control:checked ~ main .book-header aside {
    display: block;
  }
  body[dir='rtl'] #menu-control:checked ~ main .book-menu .book-menu-content {
    transform: translateX(-16rem);
  }
}
@media screen and (min-width: 80rem) {
  .book-page,
  .book-menu .book-menu-content,
  .book-toc .book-toc-content {
    padding: 2rem 1rem;
  }
}
body {
  font-family: roboto, sans-serif;
}
code {
  font-family: roboto mono, monospace;
}
@media print {
  .book-menu,
  .book-footer,
  .book-toc {
    display: none;
  }
  .book-header,
  .book-header aside {
    display: block;
  }
  main {
    display: block !important;
  }
}
.markdown {
  line-height: 1.6;
}
.markdown > :first-child {
  margin-top: 0;
}
.markdown h1,
.markdown h2,
.markdown h3,
.markdown h4,
.markdown h5,
.markdown h6 {
  font-weight: 400;
  line-height: 1;
  margin-top: 1.5em;
  margin-bottom: 1rem;
}
.markdown h1 a.anchor,
.markdown h2 a.anchor,
.markdown h3 a.anchor,
.markdown h4 a.anchor,
.markdown h5 a.anchor,
.markdown h6 a.anchor {
  opacity: 0;
  font-size: 0.75em;
  vertical-align: middle;
  text-decoration: none;
}
.markdown h1:hover a.anchor,
.markdown h1 a.anchor:focus,
.markdown h2:hover a.anchor,
.markdown h2 a.anchor:focus,
.markdown h3:hover a.anchor,
.markdown h3 a.anchor:focus,
.markdown h4:hover a.anchor,
.markdown h4 a.anchor:focus,
.markdown h5:hover a.anchor,
.markdown h5 a.anchor:focus,
.markdown h6:hover a.anchor,
.markdown h6 a.anchor:focus {
  opacity: initial;
}
.markdown h4,
.markdown h5,
.markdown h6 {
  font-weight: bolder;
}
.markdown h5 {
  font-size: 0.875em;
}
.markdown h6 {
  font-size: 0.75em;
}
.markdown b,
.markdown optgroup,
.markdown strong {
  font-weight: bolder;
}
.markdown a {
  text-decoration: none;
}
.markdown a:hover {
  text-decoration: underline;
}
.markdown a:visited {
  color: var(--color-visited-link);
}
.markdown img {
  max-width: 100%;
  height: auto;
}
.markdown code {
  padding: 0 0.25rem;
  background: var(--gray-200);
  border-radius: 0.25rem;
  font-size: 0.875em;
}
.markdown pre {
  padding: 1rem;
  background: var(--gray-100);
  border-radius: 0.25rem;
  overflow-x: auto;
}
.markdown pre code {
  padding: 0;
  background: 0 0;
}
.markdown p {
  word-wrap: break-word;
}
.markdown blockquote {
  margin: 1rem 0;
  padding: 0.5rem 1rem 0.5rem 0.75rem;
  border-inline-start: 0.25rem solid var(--gray-200);
  border-radius: 0.25rem;
}
.markdown blockquote :first-child {
  margin-top: 0;
}
.markdown blockquote :last-child {
  margin-bottom: 0;
}
.markdown table {
  overflow: auto;
  display: block;
  border-spacing: 0;
  border-collapse: collapse;
  margin-top: 1rem;
  margin-bottom: 1rem;
}
.markdown table tr th,
.markdown table tr td {
  padding: 0.5rem 1rem;
  border: 1px solid var(--gray-200);
}
.markdown table tr:nth-child(2n) {
  background: var(--gray-100);
}
.markdown hr {
  height: 1px;
  border: none;
  background: var(--gray-200);
}
.markdown ul,
.markdown ol {
  padding-inline-start: 2rem;
}
.markdown dl dt {
  font-weight: bolder;
  margin-top: 1rem;
}
.markdown dl dd {
  margin-inline-start: 0;
  margin-bottom: 1rem;
}
.markdown .highlight table tr td:nth-child(1) pre {
  margin: 0;
  padding-inline-end: 0;
}
.markdown .highlight table tr td:nth-child(2) pre {
  margin: 0;
  padding-inline-start: 0;
}
.markdown details {
  padding: 1rem;
  border: 1px solid var(--gray-200);
  border-radius: 0.25rem;
}
.markdown details summary {
  line-height: 1;
  padding: 1rem;
  margin: -1rem;
  cursor: pointer;
}
.markdown details[open] summary {
  margin-bottom: 0;
}
.markdown figure {
  margin: 1rem 0;
}
.markdown figure figcaption p {
  margin-top: 0;
}
.markdown-inner > :first-child {
  margin-top: 0;
}
.markdown-inner > :last-child {
  margin-bottom: 0;
}
.markdown .book-expand {
  margin-top: 1rem;
  margin-bottom: 1rem;
  border: 1px solid var(--gray-200);
  border-radius: 0.25rem;
  overflow: hidden;
}
.markdown .book-expand .book-expand-head {
  background: var(--gray-100);
  padding: 0.5rem 1rem;
  cursor: pointer;
}
.markdown .book-expand .book-expand-content {
  display: none;
  padding: 1rem;
}
.markdown .book-expand input[type='checkbox']:checked + .book-expand-content {
  display: block;
}
.markdown .book-tabs {
  margin-top: 1rem;
  margin-bottom: 1rem;
  border: 1px solid var(--gray-200);
  border-radius: 0.25rem;
  overflow: hidden;
  display: flex;
  flex-wrap: wrap;
}
.markdown .book-tabs label {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-bottom: 1px transparent;
  cursor: pointer;
}
.markdown .book-tabs .book-tabs-content {
  order: 999;
  width: 100%;
  border-top: 1px solid var(--gray-100);
  padding: 1rem;
  display: none;
}
.markdown .book-tabs input[type='radio']:checked + label {
  border-bottom: 1px solid var(--color-link);
}
.markdown .book-tabs input[type='radio']:checked + label + .book-tabs-content {
  display: block;
}
.markdown .book-tabs input[type='radio']:focus + label {
  outline-style: auto;
  outline-color: currentColor;
  outline-color: -webkit-focus-ring-color;
}
.markdown .book-columns {
  margin-left: -1rem;
  margin-right: -1rem;
}
.markdown .book-columns > div {
  margin: 1rem 0;
  min-width: 10rem;
  padding: 0 1rem;
}
.markdown a.book-btn {
  display: inline-block;
  font-size: 0.875rem;
  color: var(--color-link);
  line-height: 2rem;
  padding: 0 1rem;
  border: 1px solid var(--color-link);
  border-radius: 0.25rem;
  cursor: pointer;
}
.markdown a.book-btn:hover {
  text-decoration: none;
}
.markdown .book-hint.info {
  border-color: #6bf;
  background-color: rgba(102, 187, 255, 0.1);
}
.markdown .book-hint.warning {
  border-color: #fd6;
  background-color: rgba(255, 221, 102, 0.1);
}
.markdown .book-hint.danger {
  border-color: #f66;
  background-color: rgba(255, 102, 102, 0.1);
}