:root {
  --bg-main: #efede8;
  --bg-layer: #f5f3ef;
  --bg-panel: #f9f8f5;
  --bg-panel-soft: #f1efea;
  --bg-surface-start: #e9e5dc;
  --bg-surface-end: #e3dfd6;
  --bg-header: #1f2126;
  --bg-header-deep: #23252b;
  --text-main: #1f2a37;
  --text-soft: #4f5b69;
  --text-weak: #7b8490;
  --accent: #2f4f75;
  --accent-soft: rgba(47, 79, 117, 0.12);
  --border-color: rgba(41, 50, 63, 0.14);
  --header-height: 58px;
  --sidebar-width: 310px;
  --toc-width: 290px;
  --shadow-strong: 0 14px 28px rgba(32, 36, 43, 0.14);
  --shadow-soft: 0 8px 18px rgba(32, 36, 43, 0.09);
  --font-latin-math: "MJXTEX", "Latin Modern Roman", "STIX Two Text", "Times New Roman", serif;
  --font-latin-math-italic: "MJXTEX-I-Scaled", "MJXTEX-I", "MJXTEX", "Latin Modern Roman", "STIX Two Text", "Times New Roman", serif;
  --font-cn: "Source Han Serif SC", "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
}

@font-face {
  /* Same MathJax glyphs as formulas; scaled for Latin/Greek only. */
  font-family: "MJXTEX-I-Scaled";
  src: url("https://cdn.jsdelivr.net/npm/mathjax@3/es5/output/chtml/fonts/woff-v2/MathJax_Math-Italic.woff") format("woff");
  size-adjust: 112%;
  unicode-range:
    U+0000-00FF,
    U+0100-024F,
    U+0250-02AF,
    U+0370-03FF,
    U+1E00-1EFF,
    U+2C60-2C7F,
    U+A720-A7FF;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  min-height: 100%;
}

html {
  scrollbar-width: thin;
  scrollbar-color: #b9b3a8 #ece8e1;
}

body {
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background:
      radial-gradient(circle at 22% -10%, rgba(255, 255, 255, 0.85), transparent 45%),
      linear-gradient(180deg, var(--bg-main) 0%, #edeae5 100%);
  color: var(--text-main);
  font-family: var(--font-cn);
  line-height: 1.78;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

input,
button,
textarea,
select {
  font-family: inherit;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.22s ease, opacity 0.22s ease;
}

a:hover {
  color: #233a57;
}

::selection {
  color: #ffffff;
  background: rgba(72, 96, 128, 0.28);
}

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: #e8e4dd;
}

::-webkit-scrollbar-thumb {
  border-radius: 999px;
  border: 2px solid #e8e4dd;
  background: linear-gradient(180deg, #bdb7ad, #989389);
}

#app-shell {
  flex: 1;
  min-height: 0;
}

/* Header */
#header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 80;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 20px;
  height: var(--header-height);
  padding: 0 20px;
  background: linear-gradient(90deg, var(--bg-header) 0%, var(--bg-header-deep) 100%);
  box-shadow: 0 2px 10px rgba(16, 18, 23, 0.28);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.06);
  color: #f4f6fa;
  cursor: pointer;
  transition: transform 0.22s ease, background-color 0.22s ease, border-color 0.22s ease;
}

.icon-btn:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.36);
}

#title {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #f3f5f8;
  font-weight: 700;
  letter-spacing: 0.01em;
  font-size: 30px;
}

#title i {
  font-size: 22px;
}

.header-center {
  display: flex;
  justify-content: center;
}

.header-search {
  width: min(520px, 100%);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 14px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(6px);
}

.header-search i {
  color: rgba(243, 246, 251, 0.85);
}

#header-search-input {
  width: 100%;
  height: 38px;
  color: #f3f5f8;
  background: transparent;
  border: none;
  outline: none;
  font-size: 15px;
}

#header-search-input::placeholder {
  color: rgba(236, 241, 247, 0.75);
}

#menu {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 6px;
  list-style: none;
}

#menu .menu-item-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 36px;
  padding: 0 12px;
  border-radius: 8px;
  color: #edf1f7;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

#menu .menu-item-link:hover {
  background: rgba(255, 255, 255, 0.12);
}

#menu .icon-link {
  min-width: 36px;
  font-size: 20px;
}

.sidebar-mobile-toggle {
  display: none;
}

/* Left sidebar */
#sidebar {
  position: fixed;
  inset: var(--header-height) auto 0 0;
  z-index: 62;
  width: var(--sidebar-width);
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border-color);
  background: linear-gradient(180deg, var(--bg-surface-start) 0%, var(--bg-surface-end) 100%);
  box-shadow: var(--shadow-soft);
  transform: translateX(-100%);
  transition: transform 0.28s ease;
  overflow: visible;
}

body.sidebar-open #sidebar {
  transform: translateX(0);
}

.sidebar-head {
  display: none;
  align-items: center;
  justify-content: flex-end;
  padding: 12px 12px 0;
}

#sidebar-close {
  display: none;
}

.sidebar-search-wrap {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 14px 16px 6px;
  padding: 0 12px;
  border: 1px solid rgba(76, 70, 62, 0.16);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.34);
}

.sidebar-search-wrap i {
  color: #7a746b;
}

#search-input {
  width: 100%;
  height: 40px;
  color: var(--text-main);
  border: none;
  background: transparent;
  outline: none;
  font-size: 14px;
}

#search-input::placeholder {
  color: #8f887d;
}

.sidebar-float-toggle {
  position: absolute;
  top: 20px;
  right: -17px;
  width: 34px;
  height: 34px;
  border: 1px solid rgba(76, 70, 62, 0.2);
  border-radius: 50%;
  background: linear-gradient(180deg, #ece8df 0%, #e5e0d7 100%);
  color: #5d666f;
  box-shadow: 0 6px 14px rgba(32, 36, 43, 0.12);
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
  z-index: 66;
}

.sidebar-float-toggle:hover {
  background: linear-gradient(180deg, #f1ede5 0%, #e9e3da 100%);
  border-color: rgba(76, 70, 62, 0.32);
}

.sidebar-float-toggle i {
  transition: transform 0.2s ease;
}

body:not(.sidebar-open) .sidebar-float-toggle i {
  transform: rotate(180deg);
}

.sidebar-tree-wrap {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 10px 14px 24px;
}

#tree ul {
  margin: 0;
  padding-left: 14px;
}

#tree > ul {
  padding-left: 0;
}

#tree ul ul {
  display: none;
}

#tree li {
  list-style: none;
  margin: 2px 0;
}

#tree li a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 7px 10px;
  border-radius: 8px;
  color: var(--text-soft);
  font-size: 15px;
  line-height: 1.35;
  word-break: break-word;
}

#tree li a:hover {
  color: var(--text-main);
  background: rgba(98, 89, 77, 0.14);
}

#tree li.file.active > a {
  color: var(--accent);
  background: var(--accent-soft);
  border-left: 2px solid var(--accent);
}

#tree li.directory > a {
  justify-content: space-between;
  gap: 12px;
  color: #2f3948;
  font-weight: 600;
}

#tree li.file > a {
  font-size: 15px;
  font-weight: 600;
}

#tree li.directory > a span {
  flex: 1;
}

#tree li.directory > a .tree-arrow {
  font-size: 14px;
  color: #7f786e;
  transition: transform 0.2s ease;
}

#tree li.directory.is-open > a .tree-arrow {
  transform: rotate(90deg);
}

/* Overlay */
#sidebar-overlay {
  position: fixed;
  inset: var(--header-height) 0 0 0;
  z-index: 48;
  background: rgba(5, 11, 22, 0.56);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.22s ease;
}

body.sidebar-open #sidebar-overlay {
  opacity: 1;
  pointer-events: auto;
}

/* Content */
#content {
  min-height: 0;
  margin-top: calc(var(--header-height) + 26px);
  margin-left: calc(var(--sidebar-width) + 42px);
  margin-right: calc(var(--toc-width) + 44px);
  padding: 0 0 50px;
}

#content > * {
  width: min(61.8vw, calc(100vw - var(--sidebar-width) - var(--toc-width) - 86px));
  max-width: 100%;
  margin-left: auto;
  margin-right: auto;
}

#index .index-li {
  margin-bottom: 16px;
  padding: 18px 20px;
  border: 1px solid var(--border-color);
  border-radius: 14px;
  background: linear-gradient(180deg, rgba(23, 34, 54, 0.92), rgba(20, 30, 48, 0.92));
  box-shadow: var(--shadow-soft);
}

#index .index-li:hover {
  border-color: rgba(56, 194, 255, 0.5);
}

#index .index-title {
  color: #edf4ff;
  font-size: 29px;
  line-height: 1.32;
  margin: 0 0 8px;
}

#index .index-brief {
  color: var(--text-soft);
  font-size: 16px;
  font-style: normal;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 12px;
  margin-top: 10px;
  color: var(--text-weak);
  font-size: 14px;
}

.article-meta a {
  color: #8fdcff;
}

#index-paginator {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: 26px;
}

#index-paginator .extend,
#index-paginator .page-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  margin: 0 6px;
  border-radius: 10px;
  border: 1px solid rgba(135, 174, 232, 0.38);
  background: rgba(24, 39, 65, 0.88);
  color: #cad9ef;
}

#index-paginator .current,
#index-paginator .extend:hover,
#index-paginator .page-number:hover {
  color: #061321 !important;
  border-color: transparent;
  background: linear-gradient(140deg, #16d4ff, #8be1ff) !important;
}

#article-title {
  margin-bottom: 10px;
  color: var(--text-main);
  font-size: 48px;
  line-height: 1.22;
  letter-spacing: 0.01em;
}

#article-content {
  margin-top: 22px;
  padding: 24px 28px;
  border: 1px solid var(--border-color);
  border-radius: 16px;
  background: linear-gradient(180deg, var(--bg-surface-start) 0%, var(--bg-surface-end) 100%);
  box-shadow: var(--shadow-soft);
  font-family: var(--font-latin-math-italic), var(--font-cn);
  font-size: 17px;
  font-weight: 400;
  font-synthesis: none;
}

#article-content p,
#article-content li,
#article-content blockquote,
#article-content table,
#article-content th,
#article-content td {
  font-family: inherit;
  font-weight: inherit;
}

#article-content h1,
#article-content h2,
#article-content h3,
#article-content h4,
#article-content h5,
#article-content h6 {
  color: #1d2733;
  scroll-margin-top: 84px;
}

#article-content h1 {
  font-size: 36px;
  margin: 28px 0 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(58, 66, 76, 0.18);
}

#article-content h2 {
  font-size: 29px;
  margin: 34px 0 4px;
  padding-left: 0;
  border-left: none;
}

#article-content h2 + p,
#article-content h2 + ul,
#article-content h2 + ol {
  margin-top: 0;
}

#article-content h2 + blockquote,
#article-content h2 + pre,
#article-content h2 + table {
  margin-top: 8px;
}

#article-content h3 {
  margin: 20px 0 12px;
  font-size: 24px;
}

#article-content h4,
#article-content h5,
#article-content h6 {
  margin: 16px 0 10px;
}

#article-content p {
  margin-bottom: 12px;
  color: var(--text-main);
  font-size: 1em;
}

#article-content ol,
#article-content ul {
  margin: 0 0 14px;
  padding-left: 26px;
}

#article-content li {
  margin: 5px 0;
}

#article-content blockquote {
  margin: 16px 0;
  padding: 10px 16px;
  border-left: 3px solid var(--accent);
  border-radius: 0 8px 8px 0;
  background: rgba(71, 83, 98, 0.08);
  color: #314155;
}

#article-content blockquote p:last-child {
  margin-bottom: 0;
}

#article-content code {
  padding: 1px 6px;
  border-radius: 6px;
  background: rgba(12, 19, 33, 0.88);
  color: #8ce9ff;
  font-family: "JetBrains Mono", "Cascadia Mono", Consolas, monospace;
  font-size: 0.92em;
}

#article-content mjx-container[jax="CHTML"] {
  font-size: 1.16em !important;
}

#article-content pre {
  margin: 18px 0;
  border-radius: 12px;
  border: 1px solid rgba(71, 83, 98, 0.16);
  overflow: auto;
}

#article-content pre code {
  display: block;
  padding: 16px;
  background: transparent;
  color: inherit;
}

#article-content img {
  max-width: 100%;
  border-radius: 12px;
  box-shadow: var(--shadow-soft);
}

#article-content a:hover {
  text-decoration: underline;
  text-decoration-color: rgba(47, 79, 117, 0.46);
}

#article-content .about-home {
  padding-top: 6px;
}

#article-content .about-home h2 {
  position: relative;
  margin-bottom: 2px;
  line-height: 1.16;
  padding-left: 14px;
  border-left: none;
}

#article-content .about-home h2 + .about-card {
  margin-top: 0;
}

#article-content .about-home .about-card + h2 {
  margin-top: 34px;
}

#article-content .about-home h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: -0.3em;
  width: 3px;
  height: 1.04em;
  border-radius: 2px;
  background: var(--accent);
}

#article-content .about-hero {
  text-align: center;
  margin-bottom: 18px;
}

#article-content .about-avatar {
  width: 136px;
  height: 136px;
  object-fit: cover;
  border-radius: 50%;
  border: 1px solid rgba(52, 62, 77, 0.2);
  box-shadow: 0 12px 24px rgba(32, 36, 43, 0.14);
}

#article-content .about-name {
  margin: 18px 0 12px;
  padding: 0;
  border-bottom: none;
  font-size: 58px;
  line-height: 1.18;
}

#article-content .about-divider {
  border: none;
  border-top: 1px solid rgba(58, 66, 76, 0.18);
  margin: 0 0 14px;
}

#article-content .about-links {
  margin: 0;
  font-size: 22px;
  color: var(--text-soft);
}

#article-content .about-links em {
  font-style: italic;
  margin-right: 8px;
}

#article-content .about-card {
  margin: 0 0 24px;
  padding: 16px 22px;
  border: 1px solid rgba(71, 83, 98, 0.12);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.28);
}

#article-content .about-card p {
  margin: 0 0 10px;
}

#article-content .about-card p:last-child {
  margin-bottom: 0;
}

table {
  width: 100%;
  margin: 20px 0;
  border-collapse: collapse;
  border-radius: 10px;
  overflow: hidden;
}

table th,
table td {
  border: 1px solid rgba(71, 83, 98, 0.2);
  padding: 10px;
}

table th {
  background: rgba(71, 83, 98, 0.1);
}

.post-guide {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  margin-top: 22px;
  padding-top: 16px;
}

.post-guide .item {
  width: 50%;
}

.post-guide .item a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent);
}

.post-guide .right {
  text-align: right;
}

.categories,
.tags {
  color: var(--text-main);
}

#vcomments {
  margin-top: 28px;
}

/* Right toc */
#right-toc {
  position: fixed;
  top: calc(var(--header-height) + 24px);
  right: 22px;
  z-index: 42;
  width: calc(var(--toc-width) - 34px);
}

.right-toc-inner {
  max-height: calc(100vh - var(--header-height) - 44px);
  overflow-y: auto;
  padding: 14px;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  background: linear-gradient(180deg, var(--bg-surface-start) 0%, var(--bg-surface-end) 100%);
  box-shadow: var(--shadow-soft);
}

.right-toc-title {
  margin-bottom: 10px;
  color: var(--text-main);
  font-size: 19px;
  font-weight: 700;
}

#right-toc-content ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

#right-toc-content li {
  margin-bottom: 2px;
}

#right-toc-content a {
  display: block;
  padding: 6px 8px;
  border-left: 2px solid transparent;
  border-radius: 6px;
  color: var(--text-soft);
  font-size: 14px;
  line-height: 1.4;
}

#right-toc-content a:hover {
  color: var(--text-main);
  background: rgba(98, 89, 77, 0.14);
}

#right-toc-content a.is-active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-soft);
}

#right-toc-content .toc-level-2 a {
  padding-left: 18px;
}

#right-toc-content .toc-level-3 a {
  padding-left: 30px;
}

#right-toc-content .toc-level-4 a {
  padding-left: 42px;
}

.right-toc-empty {
  color: var(--text-weak);
  font-size: 14px;
}

/* Footer */
#footer {
  margin: 22px calc(var(--toc-width) + 44px) 0 calc(var(--sidebar-width) + 42px);
  padding: 14px 20px;
  border-top: 1px solid rgba(132, 166, 214, 0.28);
  color: #9eb3d4;
  font-size: 14px;
  line-height: 1.7;
}

#footer a {
  color: #bce8ff;
}

#footer .footer-author {
  color: #000;
}

#footer .footer-author:hover {
  color: #000;
}

/* Back to top */
#totop-toggle {
  position: fixed;
  right: 30px;
  bottom: 30px;
  z-index: 70;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(173, 204, 239, 0.4);
  border-radius: 50%;
  color: #f0fbff;
  background: rgba(20, 31, 49, 0.9);
  box-shadow: var(--shadow-soft);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

#totop-toggle:hover {
  transform: translateY(-1px);
}

#totop-toggle.is-visible {
  opacity: 1;
  pointer-events: auto;
}

/* Desktop defaults */
@media screen and (min-width: 1200px) {
  body {
    padding-right: 0;
  }

  #sidebar {
    transform: translateX(0);
  }

  body.sidebar-open #sidebar-overlay {
    opacity: 0;
    pointer-events: none;
  }

  #sidebar-close {
    display: none;
  }

  body:not(.sidebar-open) #sidebar {
    transform: translateX(-100%);
  }

  body:not(.sidebar-open) #content {
    margin-left: 40px;
  }

  body:not(.sidebar-open) #footer {
    margin-left: 40px;
  }
}

/* Mid-width: hide right toc */
@media screen and (max-width: 1499px) {
  #content > * {
    width: min(61.8vw, calc(100vw - var(--sidebar-width) - 76px));
  }

  #content {
    margin-right: 34px;
  }

  #footer {
    margin-right: 34px;
  }

  #right-toc {
    display: none;
  }
}

/* Tablet/mobile */
@media screen and (max-width: 1199px) {
  #header {
    grid-template-columns: auto 1fr;
    gap: 12px;
    padding: 0 12px;
  }

  #title {
    font-size: 24px;
  }

  #title span {
    max-width: 168px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .header-search {
    width: 100%;
  }

  #menu {
    gap: 2px;
  }

  #menu .menu-item-link {
    min-height: 32px;
    padding: 0 8px;
    font-size: 13px;
  }

  .sidebar-mobile-toggle {
    display: inline-flex;
    align-items: center;
  }

  .sidebar-mobile-toggle .icon-btn {
    width: 34px;
    height: 34px;
    border-radius: 8px;
  }

  #sidebar {
    z-index: 65;
  }

  .sidebar-float-toggle {
    display: none;
  }

  #sidebar-close {
    display: inline-flex;
  }

  .sidebar-head {
    display: flex;
  }

  #content {
    margin: calc(var(--header-height) + 18px) 16px 0;
    padding-bottom: 32px;
  }

  #content > * {
    width: 100%;
    max-width: 100%;
  }

  #article-title {
    font-size: 34px;
  }

  #article-content {
    padding: 18px 16px;
  }

  #article-content h1 {
    font-size: 29px;
  }

  #article-content h2 {
    font-size: 24px;
  }

  #article-content h3 {
    font-size: 21px;
  }

  #article-content .about-avatar {
    width: 112px;
    height: 112px;
  }

  #article-content .about-name {
    font-size: 46px;
  }

  #article-content .about-links {
    font-size: 18px;
  }

  #footer {
    margin: 10px 16px 0;
    padding: 14px 0 28px;
    border-top-color: rgba(132, 166, 214, 0.2);
  }

  #totop-toggle {
    right: 18px;
    bottom: 18px;
  }
}

@media screen and (max-width: 820px) {
  #menu .menu-item {
    display: none;
  }

  #menu .menu-item.sidebar-mobile-toggle {
    display: inline-flex;
  }

  #menu .menu-item:last-child {
    display: inline-flex;
  }

  #title {
    font-size: 21px;
  }

  .header-search {
    max-width: none;
  }

  .post-guide {
    flex-direction: column;
  }

  .post-guide .item {
    width: 100%;
  }

  .post-guide .right {
    text-align: left;
  }
}
.footer-beian {
    margin: 6px 0 0 0;
    text-align: center;
    font-size: 14px;
    line-height: 1.6;
}

.footer-beian a {
    color: #000!important;
    text-decoration: none;
}

.footer-beian a:hover {
    text-decoration: underline;
}