/* Blog meta vertical line */
.blog-meta-vert {
  display: inline-block;
  width: 2px;
  height: 1em;
  background: currentColor;
  border-radius: 1px;
  margin: 0 0.6em;
  align-self: center;
  opacity: 1;
  position: relative;
  top: 0;
}

:root {
  --meta-vert: #181a1b;
}
[data-theme="dark"] {
  --meta-vert: #fff;
}
/* Blog meta row styling */
.blog-meta-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.4em;
  font-size: 1.01rem;
  color: var(--nav-link);
  font-weight: 400;
  letter-spacing: 0.01em;
  margin: 0 auto 1.2em auto; /* extra space after date & author */
  text-align: center;
  position: relative;
}
.blog-meta-dot {
  font-size: 1.1em;
  color: #b0b4bb;
  opacity: 0.6;
  margin: 0 0.2em;
  user-select: none;
}
.blog-author {
  font-size: 1.08rem; /* match .blog-date */
  color: var(--nav-link);
  font-weight: 400;
  text-align: center;
  margin-bottom: 0;
  letter-spacing: 0.01em;
  padding: 0;
}
/* Blog meta separator and author styling */
.blog-separator-bar {
  width: 2.5px;
  height: 1.1em;
  background: var(--meta-vert);
  border-radius: 1.2px;
  margin: 0 0.5em 0 0.5em;
  display: inline-block;
  vertical-align: middle;
  opacity: 1;
  position: relative;
  top: 0.1em;
  color: var(--nav-link);
  text-align: center;
  margin-bottom: 1.2em;
  letter-spacing: 0.01em;
}
/* Blog post header bar and meta styling */
.blog-header-bar {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100vw;
  padding: 1.2rem 0 0.5rem 0;
  background: none;
}
.blog-date {
  font-size: 1.08rem;
  color: var(--nav-link);
  margin-bottom: 0.2em;
  letter-spacing: 0.01em;
  text-align: center;
}
.blog-title-main {
  font-size: 2.2rem;
  font-weight: 700;
  margin: 0.2em 0 0.1em 0;
  text-align: center;
  letter-spacing: 0.01em;
  color: var(--header-fg);
  position: relative;
}
.blog-subtitle-main {
  font-size: 1.18rem;
  color: var(--nav-link);
  font-weight: 400;
  margin-bottom: 2.2em;
  text-align: center;
}
/* Blog content markdown styling */
.blog-content-markdown, #blog-content {
  font-family: 'Nunito', 'Inter', 'Segoe UI', Arial, sans-serif;
  font-size: 1.08rem;
  color: var(--fg);
  line-height: 1.6; /* improved readability */
   max-width: none;
   margin: 0;
   padding: 0.5rem 0 2rem 0;
   background: none;
   border-radius: 0;
   box-shadow: none;
   transition: none;
}

  #blog-content p,
  #blog-content ul,
  #blog-content ol,
  #blog-content li,
  #blog-content .katex-display {
    text-align: left !important;
    margin-left: 0 !important;
    margin-right: 0 !important;
  }

#blog-content h1, #blog-content h2, #blog-content h3 {
  font-family: 'Nunito', 'Inter', 'Segoe UI', Arial, sans-serif;
  font-weight: 700;
  margin-top: 1.5em;
  margin-bottom: 0.5em;
}
#blog-content p {
  margin: 1em 0;
}
/* Pseudocode styling */
.pseudocode {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 0.85rem 1rem;
  border-radius: 10px;
  overflow-x: auto;
  line-height: 1.5;
  font-size: 0.98rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  counter-reset: line;
  margin: 1.1em 0;
}
.pseudocode .pseudo-code .line {
  display: block;
  white-space: pre;
}
.pseudocode .pseudo-code .line::before {
  counter-increment: line;
  content: counter(line);
  display: inline-block;
  width: 2ch;
  margin-right: 1rem;
  color: var(--nav-link);
}
.pseudocode .kw { color: var(--accent); font-weight: 700; }
.pseudocode .cm { color: #6a737d; font-style: italic; }
[data-theme="dark"] .pseudocode .cm { color: #9aa4ae; }
/* Code and tables styling */
#blog-content pre {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 0.85rem 1rem;
  border-radius: 10px;
  overflow-x: auto;
  line-height: 1.5;
  font-size: 0.95rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  margin: 1.1em 0;
}
#blog-content code {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 0.1em 0.35em;
  border-radius: 6px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
}
#blog-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2em 0;
  font-size: 0.98rem;
}
#blog-content thead th {
  text-align: left;
  border-bottom: 2px solid var(--table-border);
  padding: 0.6em 0.8em;
}
#blog-content tbody td {
  border-bottom: 1px solid var(--table-border);
  padding: 0.55em 0.8em;
}
#blog-content tbody tr:nth-child(odd) {
  background: rgba(0,0,0,0.03);
}
[data-theme="dark"] #blog-content tbody tr:nth-child(odd) {
  background: rgba(255,255,255,0.04);
}
a, a:visited {
  color: #4fa3ff;
  font-weight: 600;
  text-decoration: none;
  transition: color var(--transition);
}
a:hover, a:focus {
  color: #7ecbff;
  text-decoration: underline;
}

[data-theme="dark"] a, [data-theme="dark"] a:visited {
  color: #7ecbff;
}
[data-theme="dark"] a:hover, [data-theme="dark"] a:focus {
  color: #b3e0ff;
}
/* About page contact links */
.about-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.2rem;
  margin-top: 2.2rem;
  flex-wrap: wrap;
  font-size: 1.08rem;
  width: 100%;
}
.about-dot {
  color: var(--nav-link);
  font-size: 1.1em;
  margin: 0 0.5em;
  user-select: none;
}
.about-link {
  position: relative;
  color: var(--header-fg);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition);
  padding-bottom: 2px;
}
.about-link:visited {
  color: var(--header-fg) !important; /* prevent blue visited color */
  text-decoration: none !important;   /* avoid default underline */
}
.about-link::after {
  content: '';
  display: block;
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  background: var(--accent);
  border-radius: 1px;
  transform: scaleX(0);
  transition: transform 0.11s cubic-bezier(.7,0,.3,1);
  pointer-events: none;
}
.about-link:hover::after, .about-link:focus::after {
  transform: scaleX(1);
}
.about-link:hover, .about-link:focus {
  color: var(--header-fg); /* keep text color consistent on hover */
  text-decoration: none !important; /* remove default underline, keep only animation */
}
/* In dark mode, force about links to match header text color (not blue) */
[data-theme="dark"] .about-link,
[data-theme="dark"] .about-link:visited,
[data-theme="dark"] .about-link:hover,
[data-theme="dark"] .about-link:focus {
  color: var(--header-fg) !important;
  text-decoration: none !important;
}
.courses-list {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
  margin: 1.1em 0 0.7em 0;
}
.course-item {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  background: none;
  border-radius: 16px;
  padding: 0.7em 0.7em 0.7em 1.2em;
  box-shadow: none;
  border: none;
  transition: background 0.18s;
}
.course-meta {
  font-size: 0.98rem;
  color: var(--nav-link);
  margin-bottom: 0.1em;
  font-weight: 500;
  letter-spacing: 0.01em;
}
.course-title {
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--header-fg);
  margin-bottom: 0.08em;
}
.course-topic {
  font-size: 1.04rem;
  color: var(--nav-link);
  font-weight: 400;
  margin-bottom: 0.02em;
}
.course-list {
  list-style: decimal inside;
  padding: 0;
  margin: 0.5em 0 0.7em 0;
  max-width: 600px;
  width: 100%;
}
.course-list li {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-bottom: 0.08em;
  background: none;
  border-radius: 12px;
  padding: 0.28em 0.5em;
  font-size: 1.08rem;
  font-weight: 500;
  box-shadow: none;
  transition: background 0.18s;
}
.course-list li:hover {
  background: none;
}
.course-list .badge {
  margin-bottom: 0;
  margin-right: 0.7em;
  font-size: 0.98rem;
}
.course-list .course-title {
  font-size: 1.13rem;
  font-weight: 700;
  color: var(--header-fg);
  margin-left: 0;
  text-align: left;
}
.course-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.4rem;
  width: 100%;
  margin-bottom: 1.2em;
  padding: 0.1em 0.2em;
}
.course-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--header-fg);
  letter-spacing: 0.01em;
  margin-left: auto;
  text-align: right;
}
.badge {
  display: inline-block;
  background: #f3f4f6;
  color: #222;
  font-size: 0.97rem;
  font-weight: 600;
  border-radius: 999px;
  border: 1.2px solid #d1d5db;
  padding: 0.18em 0.95em;
  margin-bottom: 0.7em;
  letter-spacing: 0.04em;
  box-shadow: none;
  vertical-align: middle;
}
/* Styles for page sections */
.page-section {
  width: 100%;
  margin: 0 auto;
  padding: 2.5rem 0 0 0;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.page-section {
  width: 100%;
  margin: 0 auto;
  padding: 2.5rem 0 0 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-sizing: border-box;
}

#teaching-md-content, #about-md-content {
  width: 100%;
  max-width: 650px;
  margin: 0 auto;
  padding: 0;
  box-sizing: border-box;
  text-align: left;
  align-items: flex-start;
  display: flex;
  flex-direction: column;
}
#teaching-md-content > *, #about-md-content > * {
  margin-left: 0 !important;
  padding-left: 0 !important;
  text-align: left !important;
}
/* Search bar styles */
.search-bar-container {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  position: relative;
  max-width: 700px;
  margin: 1.5rem auto 0 auto;
  height: 40px;
}
.search-btn {
  position: relative;
  background: var(--header-bg, #fff);
  border: none;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  overflow: hidden;
  box-shadow: 0 1px 4px rgba(0,0,0,0.04);
  transition: box-shadow 0.15s;
}
.search-btn:active::after {
  content: '';
  position: absolute;
  left: 50%;
  top: 50%;
  width: 0;
  height: 0;
  background: rgba(79,140,255,0.18);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  animation: ripple 0.4s linear;
  z-index: 1;
}
@keyframes ripple {
  to {
    width: 120px;
    height: 120px;
    opacity: 0;
  }
}
.search-icon {
  font-size: 1.3rem;
  color: var(--accent);
}
.search-input {
  margin-left: 1rem;
  padding: 0.5rem 1rem;
  font-size: 1rem;
  border: 1.5px solid var(--accent);
  border-radius: 999px;
  outline: none;
  background: var(--bg);
  color: var(--fg);
  box-shadow: 0 1px 4px rgba(0,0,0,0.04);
  transition: width 0.18s cubic-bezier(.7,0,.3,1), opacity 0.18s cubic-bezier(.7,0,.3,1);
  width: 0;
  opacity: 0;
  pointer-events: none;
}
.search-bar-container.active .search-input {
  width: 220px;
  opacity: 1;
  pointer-events: auto;
  display: block;
}
.blog-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  text-decoration: none;
  color: inherit;
  padding: 0.2rem 0;
  background: none;
  border: none;
  margin: 0;
  position: relative;
  transition: color var(--transition);
}
.blog-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 0%;
  background: var(--accent);
  border-radius: 6px;
  transition: height 0.22s cubic-bezier(.7,0,.3,1);
  z-index: 1;
}
.blog-item:hover::before, .blog-item:focus::before {
  height: 100%;
}
.blog-item:hover, .blog-item:focus {
  color: var(--nav-link-active);
  outline: none;
}
.blog-item {
  /* ...existing code... */
  z-index: 1;
}
.blog-item {
  display: flex;
  flex-direction: column;
  gap: 0;
  text-decoration: none;
  color: inherit;
  padding: 0.05rem 0.1rem 0.05rem 1.2rem;
  background: none;
  border: none;
  margin: 0;
  position: relative;
  transition: color var(--transition);
  border-radius: 16px;
  overflow: hidden;
  z-index: 1;
}
.blog-meta {
  margin-bottom: 0;
  color: var(--header-fg);
}
.blog-title {
  margin: 0;
  color: var(--header-fg);
}
.blog-subtitle {
  margin-bottom: 0;
}
.blog-subtitle {
  font-size: 1.05rem;
  color: var(--nav-link);
  font-weight: 400;
  margin-bottom: 0;
}
.blogs {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.5rem;
  margin-top: 0.0rem;
}
.blogs-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: 0.01em;
}
.blogs-list {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}
.divider {
  width: 100vw;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, var(--nav-link) 20%, var(--nav-link) 80%, transparent 100%);
  margin: 0 auto;
  border: none;
  opacity: 0.25;
}
/* Modern, minimal, and elegant styles for math/code blog */
:root {
  --bg: #f8f9fb;
  --fg: #181a1b;
  --accent: #4f8cff;
  --header-bg: #fff;
  --header-fg: #181a1b;
  --nav-link: #888;
  --nav-link-active: var(--accent);
  --shadow: 0 2px 16px rgba(0,0,0,0.04);
  --border-radius: 16px;
  --transition: 0.2s cubic-bezier(.4,0,.2,1);
  --code-bg: #f2f4f8;
  --code-fg: #0b1f33;
  --table-border: rgba(0,0,0,0.12);
}

[data-theme="dark"] {
  --bg: #181a1b;
  --fg: #f8f9fb;
  --accent: #4f8cff;
  --header-bg: #23272e;
  --header-fg: #fff;
  --nav-link: #aaa;
  --nav-link-active: var(--accent);
  --shadow: 0 2px 24px rgba(0,0,0,0.24);
  --code-bg: #23272e;
  --code-fg: #e6edf3;
  --table-border: rgba(255,255,255,0.18);
}

html, body {
  height: 100%;
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: 'Nunito', 'Inter', 'Segoe UI', Arial, sans-serif;
  transition: background var(--transition), color var(--transition);
}

.header {
  width: 100vw;
  position: sticky;
  top: 0;
  z-index: 10;
  background: none;
  box-shadow: none;
  border-radius: 0;
  padding: 0;
}

.header-inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--header-fg);
  width: 100%;
  padding: 1.5rem 2.5rem 1.5rem 2.5rem;
  box-sizing: border-box;
  min-width: 0;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 2rem;
  min-width: 0;
}
.logo {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--header-fg) !important;
  text-decoration: none !important;
  position: relative;
  cursor: pointer;
  text-decoration: none !important;
}
.logo::after {
  content: '';
  display: block;
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  background: var(--accent);
  border-radius: 1px;
  transform: scaleX(0);
  transition: transform 0.11s cubic-bezier(.7,0,.3,1);
  pointer-events: none;
}
.logo:hover::after, .logo:focus::after {
  transform: scaleX(1);
}
.logo:active::after {
  /* Prevent underline from staying after click */
  transform: scaleX(0) !important;
}
.nav {
  display: flex;
  gap: 2rem;
}
.nav-link {
  text-decoration: none !important;
  color: var(--header-fg) !important;
  font-size: 1.1rem;
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
  padding-bottom: 2px;
}
.nav-link:visited {
  text-decoration: none !important;
  color: var(--header-fg) !important;
}
/* Force nav links to always be header-fg, even when active/current */
.nav-link-active,
.nav-link[aria-current="page"] {
  color: var(--header-fg) !important;
}
.nav-link::after {
  content: '';
  display: block;
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2px;
  background: var(--accent);
  border-radius: 1px;
  transform: scaleX(0);
  transition: transform 0.11s cubic-bezier(.7,0,.3,1);
  pointer-events: none;
}
.nav-link:hover::after, .nav-link:focus::after {
  transform: scaleX(1);
}
.nav-link:hover, .nav-link:focus {
  color: var(--header-fg);
}
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.3rem;
  margin-left: 2rem;
  color: var(--header-fg);
  transition: color var(--transition);
}
.theme-toggle .icon-sun {
  display: none;
}
[data-theme="dark"] .theme-toggle .icon-moon {
  display: none;
}
[data-theme="dark"] .theme-toggle .icon-sun {
  display: inline;
}

.main-content {
  max-width: 700px;
  margin: 0.2rem auto 0 auto;
  /* Add a bit more horizontal breathing room */
  padding: 0.2rem 1.25rem 0 1.25rem;
  background: none;
  border-radius: 0;
  box-shadow: none;
  transition: none;
  display: flex;
  flex-direction: column;
  align-items: center;
}
[data-page="blog"] .main-content,
.main-content.blog-post {
  /* Narrower content to avoid touching monitor edges on wide screens */
  max-width: 720px;
  /* Ensure children (meta + content) align with the left edge of this container */
  align-items: flex-start;
}
[data-theme="dark"] .main-content {
  background: none;
}
.hero {
  text-align: center;
  margin-bottom: 2rem;
}
.hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}
.subtitle {
  font-size: 1.2rem;
  color: var(--nav-link);
  font-weight: 400;
}

@media (max-width: 600px) {
  .header-inner {
    flex-direction: row;
    align-items: center;
    padding: 1rem;
    max-width: 100%;
  }
  .main-content {
    padding: 1rem;
    max-width: 100%;
  }
  .nav {
    gap: 1rem;
  }
  .header-actions {
    gap: 1rem;
  }
}

/* Ensure blog meta and content span the full width of the constrained container */
.main-content.blog-post #blog-meta,
.main-content.blog-post #blog-content {
  width: 100%;
}

/* Site footer */
.site-footer {
  width: 100%;
  margin-top: 2rem;
  padding: 1.5rem 1rem;
  text-align: center;
  color: var(--nav-link);
}
.footer-inner {
  max-width: 800px;
  margin: 0 auto;
  font-size: 0.95rem;
}