:root {
  --fonts-sans-serif: Roboto, Helvetica, Tahoma, Arial,
                      "DejaVu Sans", "Liberation Sans",

                      "WenQuanYi Zen Hei", "WenQuanYi Micro Hei",
                      "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
                      "Noto Sans CJK",
                      sans-serif;

  --fonts-serif: PMingLiu, "Times New Roman",
                 "Noto Serif CJK", STSong, SimSun,
                 serif;

  --fonts-mono: "DejaVu Sans Mono", "Liberation Mono", "Noto Sans Mono", "Consolas", "Courier",
                "Noto Sans Mono CJK",
                "WenQuanYi Zen Hei Mono",
                "WenQuanYi Micro Hei Mono",
                monospace;

  --color-light-1: #e0e0e0;
  --color-light-2: #e8e8e8;
  --color-light-3: #f0f0f0;
  --color-light-4: #f4f4f4;
  --color-light-5: #fefefe;

  --color-black-0: #909090;
  --color-black-1: #686868;
  --color-black-2: #404040;
  --color-black-3: #282828;
  --color-black-4: #101010;
  --color-black-5: #020202;

  --color-fav-0: #EDD5DD;
  --color-fav-1: #F0B3B2;
  --color-fav-2: #DE629E;
  --color-fav-3: #CB3E50;

  --len-0: 0.00rem;
  --len-1: 0.25rem;
  --len-2: 0.50rem;
  --len-3: 1.00rem;
  --len-4: 1.50rem;
  --len-5: 3.00rem;

  --font-size-0: 0.8125rem;
  --font-size-1: 0.875rem;
  --font-size-2: 1.000rem;
  --font-size-3: 1.125rem;
  --font-size-4: 1.250rem;
  --font-size-5: 1.500rem;
  --font-size-6: 2.000rem;
}

*, ::before, ::after {
  font-family: inherit;
  box-sizing: border-box;
}

html {
  font-family: var(--fonts-sans-serif);
  font-size: 16px;
  color: var(--color-black-3);
}

/**************************************************************/
/* approximately set up the layout of header, footer and main */
/**************************************************************/

body {
  display: flex;
  flex-direction: column;

  min-height: 100vh;
  margin: 0;

  align-items: center;

  background-color: var(--color-light-4);
}

/* set up padding and margin of some main elements */
.main-wrapper {
  margin-top: var(--len-5);
  margin-bottom: var(--len-5);
}

.main-wrapper { display: flex; flex-wrap: wrap; }
.main-wrapper > * { height: fit-content; }

.main { padding: var(--len-4); }
.side { padding-left: var(--len-4); }
.main { flex: 0 0 72%; width: 72%; }
.side { flex: 0 0 28%; width: 28%; }

@media (max-width: 991px) {
  .main { padding: var(--len-4); }
  .side { padding-left: 0; padding-top: var(--len-4); }
  .main { flex: 0 0 100%; width: 100%; }
  .side { flex: 0 0 100%; width: 100%; }
}

/* set light background */
.header-wrapper,
.footer,
.main,
.side-recent,
.side-categories,
.side-tags
{ background-color: var(--color-light-5); }

/* place header in the center of header-wrapper */
.header-wrapper {
  display: flex;
  justify-content: center;
}

/* let footer stay at bottom of screen */
.footer {
  margin-top: auto;
  margin-bottom: 0;
}


/********** set up break point **********/

                             .main-wrapper, .header { max-width: 1320px; }
@media (max-width: 1399px) { .main-wrapper, .header { max-width: 1140px; } }
@media (max-width: 1199px) { .main-wrapper, .header { max-width: 960px; } }
@media (max-width: 991px)  { .main-wrapper, .header { max-width: 720px; } }
@media (max-width: 767px)  { .main-wrapper, .header { max-width: 540px; } }
@media (max-width: 575px)  { .main-wrapper, .header { max-width: none; } }

/* size the element who has breakpoint limitation */
/* .header, .main-wrapper, .main { width: 100vw; } */
/* .header-wrapper, .footer { width: 100vw; } */
.header-wrapper, .footer { width: 100vw;}
.main-wrapper { width: calc(100vw - 2 * var(--len-3));}

/************************/
/* set up header layout */
/************************/

.header {
  padding: var(--len-3);
  width: 100%;
}

/* place title and menus horizonally */
.header {
  display: flex;
  flex-wrap: wrap;
  align-content: center;
  justify-content: space-between;
}

.header .menu { justify-content: center; align-items: center; }
.header .site-title { text-align: center; }

@media (max-width: 767px) {
  .header .site-title {
    padding-top: var(--len-4);

    flex: 0 0 100%;
  }

  .header .menu {
    flex-wrap: wrap;
    flex: 0 0 100%;

    margin-top: var(--len-3);
    padding-top: var(--len-3);
    border-top: 1px solid var(--color-light-1);
  }
}

/* setup hyper link style */
.header .site-title {
  text-decoration: none;
  font-family: var(--fonts-serif);
  font-size: var(--font-size-6);
  font-weight: bold;
}

/********** set up menus layout **********/

/* menus and submenus, hover to display, and setup animation */
.header .menu-item       .sub-menu { visibility: hidden;  opacity: 0; transition: opacity 0.25s, visibility 0.25s; }
.header .menu-item:hover .sub-menu { visibility: visible; opacity: 1; }
.header .sub-menu { position: absolute; }

/* menu direction */
.header .menu {
  display: flex;
  align-items: center;
}
.header .sub-menu {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

/* remove the unwanted default css in menus */
.header ul { list-style: none; margin: 0; padding: 0; }
.header li { list-style: none; }

/* set up spacing of menu items in menu and sub-menu */
.header .menu > *            { margin-right: var(--len-3); }
.header .menu > *:last-child { margin-right: 0; }
.header .sub-menu > *            { margin-bottom: var(--len-2); }
.header .sub-menu > *:last-child { margin-bottom: 0; }

/* beautify sub menu style */
.header .sub-menu {
  background-color: var(--color-light-5);
  padding: var(--len-2) var(--len-4);
  box-shadow: var(--color-light-1) 0px 0px 3px 1px;
  border-radius: 3px;
}

/* beautify menu item */
.header .menu-item {
  font-family: var(--fonts-serif);
  font-size: var(--font-size-3);
  font-weight: bold;
}

.header a       { color: var(--color-black-3); text-decoration: none; }
.header a:hover { color: var(--color-fav-2); }

/************************/
/* set up footer layout */
/************************/

.footer {
  padding: var(--len-4) 0;
  font-size: var(--font-size-1);
}

.footer > * {
  margin-top: var(--len-2);
  margin-bottom: var(--len-2);
}

/* credit, license and social layout */
.footer .footer-row { display: flex; justify-content: center; }

.footer .footer-item            { margin-right: var(--len-3); }
.footer .footer-item:last-child { margin-right: 0; }

/* beautify hyper link style */
.footer { color: var(--color-black-1) }

.footer a       { color: var(--color-fav-2); text-decoration: none; }
.footer a:hover { color: var(--color-fav-3); }

.footer img {
    display: inline;
    height: var(--font-size-1);
    color: var(--color-fav-2);
}

/**********************************/
/* set up home page's list layout */
/**********************************/

.list-item .tips {
  display: flex;
  flex-wrap: wrap;
  justify-content: start;
  align-items: flex-start;

  font-size: var(--font-size-1);
  color: var(--color-black-1);
}

.list-item .tips > *            { margin-right: var(--len-3); }
.list-item .tips > *:last-child { margin-right: 0; }

.list-item .title a { text-decoration: none; color: var(--color-black-2); }
.list-item .title a:hover { color: var(--color-fav-2); }
.list-item .tips a { text-decoration: none; color: var(--color-fav-2) }
.list-item .tips a:hover { color: var(--color-fav-3) }

.list-item .title { margin: var(--len-2) 0 var(--len-3) 0; }

.list-item .tags > *,
.list-item .categories > *
{ margin: 0 var(--len-1); }

.list-item .summary > * { margin: 0; }
.list-item .title { margin: 0 0 var(--len-2) 0; }
.list-item .tips { margin: 0 0 var(--len-3) 0; }

.list-item            { border-bottom: 1px solid var(--color-light-2); }
.list-item:last-child { border-bottom: 0; }

.list-item:first-child { padding-top: 0;}
.list-item             { padding: var(--len-3) 0; }
.list-item:last-child  { padding-bottom: 0;}

/**********************/
/* set up side layout */
/**********************/

.side h2 { margin: 0; }

.side ul { list-style: none; margin: 0; padding: 0; }

.side li            { margin-bottom: var(--len-3); }
.side li:last-child { margin-bottom: 0; }

.side hr {
  border: none;
  height: 1px;
  background-color: var(--color-light-2);

  margin: var(--len-2) 0;
}

.side > * { padding: var(--len-4); }

.side > *            { margin-bottom: var(--len-3); }
.side > *:last-child { margin-bottom: 0; }

.side a       { color: var(--color-black-3); text-decoration: none; }
.side a:hover { color: var(--color-fav-2); }

/* horizontally place tags */
.side .side-tags li { display: inline-block; margin: var(--len-1) var(--len-1); }

/*****************************/
/* set up single post layout */
/*****************************/

.single {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.single a { text-decoration: none; color: var(--color-fav-2); }
.single a:hover { color: var(--color-fav-3); }

.single .title,
.single .tip,
.single .taxonomies,
.single .content
{ width: 100%; }

.single .taxonomies { margin-top: var(--len-1); }

.single > hr {
  border: none;
  background-color: var(--color-fav-1);
  height: 1px;

  width: 90%;
  margin: var(--len-3) 0;
}

.single .title,
.single .tip,
.single .taxonomies
{ text-align: center; }

.single .tip,
.single .taxonomies
{ color: var(--color-black-1)}

.single .taxonomies > * { display: inline-block; }

.single .taxonomies > * { margin-right: var(--len-3); }
.single .taxonomies > *:last-child { margin-right: 0; }

.single .title {
  margin: var(--len-2) 0 var(--len-3) 0;
  font-size: var(--font-size-6);
}


/***** set up content style *****/

.content p code {
  font-family: var(--fonts-mono);

  background-color: var(--color-light-4);

  padding: 0 2px;
  border: 1px solid var(--color-light-1);
  border-radius: 2px;
  line-height: inherit;
  word-wrap: break-word;
}

/* keep in style with highlighting */
.content pre { padding: 7px; }

.content pre code {
  font-family: var(--fonts-mono);

  display: inline-block;

  padding: var(--len-3);

  background-color: var(--color-light-4);
  border-radius: 3px;

  overflow: auto;
  width: 100%;
}

.content blockquote {
  margin-top: 5px;
  margin-bottom: 5px;
  padding-left: 1em;
  margin-left: 0px;
  border-left: 3px solid #eee;
  color: var(--color-black-1);
}

.content hr {
  border: none;
  height: 2px;
  background-color: var(--color-light-4);

  width: 80%;
  margin: var(--len-2) auto;
}

.content table {
  width: 100%;
  margin: 40px 0;
  border-collapse: collapse;
  line-height: 1.5em;
}

.content th, td {
  text-align: left;
  padding-right: 20px;
  vertical-align: top;
}

.content table td, td {
  border-spacing: none;
  border-style: solid;
  padding: 10px 15px;
  border-width: 1px 0 0 0;
}
.content thead th, th {
  text-align: left;
  padding: 10px 15px;
  height: 20px;
  font-weight: bold;
  color: #444;
  cursor: default;
  white-space: nowrap;
  border: 1px solid #dadadc;
}

.content tr>td {
  border: 1px solid #dadadc;
}

.content tr:nth-child(odd)>td {
  background: #fcfcfc;
}

.content h1,
.content h2,
.content h3 {
  font-weight: bold;
}
.content p,
.content pre {
  word-break: normal;
  overflow-wrap: anywhere;
}
.content .markdown-image img {
  max-width: 100%;
}
.content .anchor {
  visibility: hidden;
  color: var(--color-fav-2);
}
.content h1:hover a,
.content h2:hover a,
.content h3:hover a,
.content h4:hover a
{ visibility: visible }

.highlight pre {
  padding: 7px;
  overflow-x: auto;
}

.highlight {
  max-width: 100%;
  overflow-x: auto;
}

/**************************/
/* setup list page layout */
/**************************/

#archive {
  padding-left: var(--len-3);
}

#archive .group {
  margin: var(--len-4) auto;
}
#archive .group .key {
  font-size: var(--font-size-4);
  margin-bottom: var(--len-2);
}
#archive .group .value {
  display: block;
  font-size: var(--font-size-2);
  margin-bottom: 12px;
}
#archive .group .value   { text-indent: -60px; padding-left: 60px; }
#archive .group .value * { text-indent: 0; }
#archive .group .value .date  { display: inline-block; width: 60px; }
#archive .group .value .title { display: inline; }

#archive .group .value .date { color: var(--color-black-0); }

#archive .group .value a { text-decoration: none; }

#archive .group .value a { color: var(--color-black-3); }
#archive .group .value a:hover { color: var(--color-fav-2); }

#archive .group .value .tags {
  display: inline-block;
  margin-left: 7px;
}
#archive .group .value .tags {
  background: var(--color-light-4);
  border-radius: 2px;
  padding: 4px 7px;
  font-size: var(--font-size-1);
  margin-right: 3px;
}

/**********************/
/* setup terms layout */
/**********************/

#tags {
  max-width: 700px;
  margin: 48px auto 0 auto;
  padding: 0 12px;
  text-align: center;
}
#tags .tag {
  display: inline-block;
  margin: 7px 7px;
}
@media (max-width: 700px) {
  #tags {
    margin: 0 auto 0 auto;
  }
  #tags .tag {
    display: inline-block;
    margin: 4px 5px;
  }
}

#tags .tag a {
  background: #f2f2f2;
  padding: 4px 7px;
  color: #757575;
  color: #404040;
  font-size: 14px;
  margin-right: 3px;
}
#tags .tag a:hover {
  color: #0366d6;
}

/***************************/
/* setup pagination layout */
/***************************/

.pagination {
  width: 100%;
  text-align: center;

  padding-top: var(--len-5);
}

.pagination a {
  display: inline-block;

  font-size: var(--font-size-2);

  border-radius: var(--len-5);
  width: var(--len-5);
  height: var(--len-5);
  line-height: var(--len-5);

  text-align: center;
  vertical-align: middle;

  text-decoration: none;

  color: var(--color-black-2);
  background-color: var(--color-light-3);

  transition: background-color 0.25s;
}

.pagination a:hover {
  background-color: var(--color-fav-0);
}

.pagination a.current {
  background-color: var(--color-fav-1);
  pointer-events: none;
  color: var(--color-black-1);
  cursor: default;
}

/***************************/
/* setup commenting layout */
/***************************/

.commenting {
  width: 85%;
}

/* keep content style from being affected by remark42 style */
.content pre {
  background-color: transparent;
  color: var(--color-black-3)
}

/**********/
/** misc **/
/**********/

.archive-hint {
  padding-left: var(--len-4);
  color: var(--color-fav-1);
}

.max-wrapper {
  width: 100%;
  height: 100%;
  padding: 0;
  margin: 0;
}