/* ===== Reset & Variables ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #A60000;
  --primary-light: #c41919;
  --primary-dark: #8a0000;
  --contrary: #00A6A6;
  --contrary-light: #00c4c4;
  --contrary-dark: #008a8a;
  --text: #1a1a1a;
  --text-secondary: #555;
  --text-light: #888;
  --bg: #ffffff;
  --bg-alt: #f8f7f5;
  --border: #e0e0e0;
  --border-light: #eee;
  --navbar-bg: rgba(255, 255, 255, 0.92);
  --nav-dropdown-bg: rgba(255, 255, 255, 0.98);
  --card-bg: #ffffff;
  --font-main: 'Palatino', 'Palatino Linotype', 'Book Antiqua', Georgia, serif;
}

[data-theme="dark"] {
  --primary: #e05050;
  --primary-light: #ff6b6b;
  --primary-dark: #cc3333;
  --contrary: #00d4d4;
  --contrary-light: #00f0f0;
  --contrary-dark: #00b0b0;
  --text: #e0e0e0;
  --text-secondary: #aaa;
  --text-light: #777;
  --bg: #121212;
  --bg-alt: #1a1a1a;
  --border: #333;
  --border-light: #2a2a2a;
  --navbar-bg: rgba(18, 18, 18, 0.92);
  --nav-dropdown-bg: rgba(18, 18, 18, 0.98);
  --card-bg: #1e1e1e;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: var(--font-main);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  transition: background 0.3s, color 0.3s;
}

a {
  color: var(--contrary);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--contrary-dark);
}

img {
  max-width: 100%;
  height: auto;
}

/* ===== Layout ===== */
.container {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 72px 0;
  background: var(--bg);
  transition: background 0.3s;
}

.section-alt {
  background: var(--bg-alt);
}

.section-title {
  font-size: 1.6rem;
  color: var(--primary);
  margin-bottom: 36px;
  font-weight: 700;
  letter-spacing: 0.01em;
}

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--navbar-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  height: 60px;
  display: flex;
  align-items: center;
  transition: background 0.3s, border-color 0.3s;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.nav-brand {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: 0.02em;
}

.nav-brand:hover {
  color: var(--primary-dark);
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.92rem;
  transition: color 0.2s;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* Theme Toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  padding: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: all 0.2s;
  flex-shrink: 0;
}

.theme-toggle:hover {
  border-color: var(--contrary);
  color: var(--contrary);
}

.icon-moon {
  display: none;
}

[data-theme="dark"] .icon-sun {
  display: none;
}

[data-theme="dark"] .icon-moon {
  display: block;
}

/* Mobile Nav Toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: 0.3s;
}

/* ===== About Section ===== */
#about {
  padding-top: 120px;
}

.about-grid {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 48px;
  align-items: start;
}

.portrait-wrapper img {
  width: 200px;
  height: 200px;
  border-radius: 10px;
  object-fit: cover;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
}

.about-name {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 2px;
  line-height: 1.2;
}

.about-title {
  font-size: 1.05rem;
  color: var(--primary);
  margin-bottom: 16px;
  font-weight: 500;
}

.about-bio {
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.8;
  font-size: 0.98rem;
}

.about-bio a {
  color: var(--contrary);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s, color 0.2s;
}

.about-bio a:hover {
  border-bottom-color: var(--contrary);
}

.about-bio strong {
  color: var(--text);
  font-weight: 700;
}

.social-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 14px;
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.88rem;
  transition: all 0.2s;
}

.social-links a:hover {
  border-color: var(--contrary);
  color: var(--contrary);
  background: rgba(0, 166, 166, 0.04);
}

[data-theme="dark"] .social-links a:hover {
  background: rgba(0, 212, 212, 0.08);
}

.social-links svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* ===== News Section ===== */
.news-list {
  list-style: none;
}

.news-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  gap: 16px;
  font-size: 0.95rem;
}

.news-list li:last-child {
  border-bottom: none;
}

.news-date {
  color: var(--text-light);
  font-size: 0.88rem;
  min-width: 100px;
  flex-shrink: 0;
}

.news-content {
  color: var(--text-secondary);
}

.news-content a {
  color: var(--contrary);
  font-weight: 600;
}

.news-content a:hover {
  text-decoration: underline;
}

.news-highlight {
  color: var(--primary);
  font-weight: 600;
}

/* ===== Publications Section ===== */
.pub-note {
  color: var(--text-light);
  font-size: 0.9rem;
  margin-bottom: 8px;
  font-style: italic;
}

.research-direction {
  font-size: 1.05rem;
  color: var(--text);
  margin: 36px 0 4px;
  padding-bottom: 6px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 10px;
}

.research-direction::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 20px;
  background: var(--primary);
  border-radius: 2px;
  flex-shrink: 0;
}

.pub-list {
  margin-bottom: 8px;
}

.pub-entry {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 20px;
  padding: 18px 0;
  border-bottom: 1px solid var(--border-light);
  align-items: start;
}

.pub-list .pub-entry:last-child {
  border-bottom: none;
}

.pub-thumb {
  width: 180px;
  height: 115px;
  border-radius: 6px;
  overflow: hidden;
  background: var(--bg-alt);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  flex-shrink: 0;
}

.pub-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}

.pub-entry:hover .pub-thumb img {
  transform: scale(1.03);
}

.pub-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 3px;
  line-height: 1.4;
}

.pub-authors {
  font-size: 0.88rem;
  color: var(--text-secondary);
  margin-bottom: 3px;
  line-height: 1.5;
}

.pub-authors .me {
  font-weight: 700;
  color: var(--primary);
}

.pub-venue {
  font-size: 0.88rem;
  color: var(--text-light);
  margin-bottom: 8px;
}

.pub-badge {
  display: inline-block;
  padding: 1px 8px;
  background: var(--primary);
  color: white;
  font-size: 0.72rem;
  border-radius: 3px;
  margin-left: 6px;
  font-weight: 600;
  vertical-align: middle;
  letter-spacing: 0.02em;
}

.pub-links {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.pub-links a {
  display: inline-block;
  padding: 2px 12px;
  border: 1px solid var(--contrary);
  color: var(--contrary);
  text-decoration: none;
  font-size: 0.78rem;
  border-radius: 4px;
  transition: all 0.2s;
  font-weight: 500;
}

.pub-links a:hover {
  background: var(--contrary);
  color: white;
}

/* ===== Blog Preview Section ===== */
.blog-preview-list {
  margin-bottom: 20px;
}

.blog-preview-item {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-light);
  text-decoration: none;
  color: var(--text);
  transition: color 0.2s;
}

.blog-preview-item:last-child {
  border-bottom: none;
}

.blog-preview-item:hover {
  color: var(--contrary);
}

.blog-preview-item:hover .blog-preview-title {
  color: var(--contrary);
}

.blog-preview-date {
  color: var(--text-light);
  font-size: 0.88rem;
  min-width: 80px;
  flex-shrink: 0;
}

.blog-preview-title {
  font-weight: 600;
  flex: 1;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.blog-preview-tag {
  font-size: 0.75rem;
  padding: 1px 10px;
  border-radius: 12px;
  background: var(--bg);
  color: var(--text-light);
  border: 1px solid var(--border);
  flex-shrink: 0;
  transition: background 0.3s, border-color 0.3s;
}

[data-theme="dark"] .blog-preview-tag {
  background: var(--card-bg);
}

.blog-view-all {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: var(--contrary);
  font-weight: 600;
  font-size: 0.95rem;
}

.blog-view-all:hover {
  text-decoration: underline;
}

/* ===== Projects Section ===== */
.project-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.project-card {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 24px;
  padding: 20px;
  background: var(--card-bg);
  border-radius: 10px;
  border: 1px solid var(--border-light);
  align-items: center;
  transition: box-shadow 0.3s, background 0.3s, border-color 0.3s;
}

.project-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.07);
}

[data-theme="dark"] .project-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.project-thumb {
  width: 260px;
  height: 170px;
  border-radius: 8px;
  overflow: hidden;
  background: var(--bg-alt);
}

.project-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.project-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
  line-height: 1.4;
}

.project-tldr {
  color: var(--text-secondary);
  font-size: 0.92rem;
  margin-bottom: 12px;
  line-height: 1.6;
}

.project-links {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.project-links a {
  display: inline-block;
  padding: 3px 14px;
  border: 1px solid var(--contrary);
  color: var(--contrary);
  text-decoration: none;
  font-size: 0.82rem;
  border-radius: 4px;
  transition: all 0.2s;
  font-weight: 500;
}

.project-links a:hover {
  background: var(--contrary);
  color: white;
}

/* ===== Experience Section ===== */
.exp-list {
  position: relative;
}

.exp-list::before {
  content: '';
  position: absolute;
  left: 160px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-light);
}

.exp-entry {
  display: grid;
  grid-template-columns: 148px 1fr;
  gap: 24px;
  padding: 20px 0;
  border-bottom: 1px solid var(--border-light);
  position: relative;
}

.exp-entry:last-child {
  border-bottom: none;
}

.exp-entry::after {
  content: '';
  position: absolute;
  left: 155px;
  top: 26px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--primary);
  border: 2px solid var(--bg-alt);
  z-index: 1;
}

.exp-date {
  color: var(--text-light);
  font-size: 0.86rem;
  padding-top: 2px;
  text-align: right;
}

.exp-info {
  padding-left: 16px;
}

.exp-org {
  font-weight: 700;
  color: var(--text);
  font-size: 1rem;
  margin-bottom: 2px;
}

.exp-role {
  color: var(--primary);
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 6px;
}

.exp-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ===== Blog Page ===== */
.blog-page-header {
  padding-top: 120px;
  padding-bottom: 20px;
  background: var(--bg);
  transition: background 0.3s;
}

.blog-page-header .section-title {
  margin-bottom: 8px;
}

.blog-page-subtitle {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.blog-page-content {
  padding: 20px 0 72px;
  background: var(--bg);
  transition: background 0.3s;
}

.blog-entry {
  padding: 28px 0;
  border-bottom: 1px solid var(--border-light);
}

.blog-entry:last-child {
  border-bottom: none;
}

.blog-entry-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.blog-entry-meta {
  display: flex;
  gap: 12px;
  align-items: center;
  margin-bottom: 12px;
}

.blog-entry-date {
  color: var(--text-light);
  font-size: 0.88rem;
}

.blog-entry-tag {
  font-size: 0.75rem;
  padding: 1px 10px;
  border-radius: 12px;
  background: var(--bg-alt);
  color: var(--text-light);
  border: 1px solid var(--border);
}

.blog-entry-summary {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
  margin-bottom: 12px;
}

.blog-entry-links {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.blog-entry-links a {
  display: inline-block;
  padding: 3px 14px;
  border: 1px solid var(--contrary);
  color: var(--contrary);
  text-decoration: none;
  font-size: 0.82rem;
  border-radius: 4px;
  transition: all 0.2s;
  font-weight: 500;
}

.blog-entry-links a:hover {
  background: var(--contrary);
  color: white;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--contrary);
  font-size: 0.92rem;
  font-weight: 500;
  margin-bottom: 16px;
}

.back-link:hover {
  text-decoration: underline;
}

/* Blog entry title links */
.blog-entry-title a {
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
}

.blog-entry-title a:hover {
  color: var(--contrary);
}

/* ===== Blog Post Body (rendered markdown) ===== */
.blog-post-body {
  line-height: 1.8;
  font-size: 1rem;
  color: var(--text);
}

.blog-post-body h2 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text);
  margin: 40px 0 16px;
  padding-bottom: 6px;
  border-bottom: 2px solid var(--border-light);
}

.blog-post-body h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  margin: 32px 0 12px;
}

.blog-post-body h4 {
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--text);
  margin: 24px 0 8px;
}

.blog-post-body p {
  margin: 0 0 16px;
  color: var(--text-secondary);
}

.blog-post-body a {
  color: var(--contrary);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}

.blog-post-body a:hover {
  border-bottom-color: var(--contrary);
}

.blog-post-body strong {
  color: var(--text);
  font-weight: 700;
}

.blog-post-body em {
  font-style: italic;
}

.blog-post-body ul,
.blog-post-body ol {
  margin: 0 0 16px 24px;
  color: var(--text-secondary);
}

.blog-post-body li {
  margin-bottom: 6px;
}

.blog-post-body img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  margin: 16px 0;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

[data-theme="dark"] .blog-post-body img {
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.blog-post-body blockquote {
  border-left: 3px solid var(--primary);
  padding: 8px 16px;
  margin: 16px 0;
  color: var(--text-secondary);
  background: var(--bg-alt);
  border-radius: 0 6px 6px 0;
}

.blog-post-body code {
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 0.88em;
  padding: 2px 6px;
  background: var(--bg-alt);
  border: 1px solid var(--border-light);
  border-radius: 4px;
  color: var(--primary);
}

.blog-post-body pre {
  background: var(--bg-alt);
  border: 1px solid var(--border-light);
  border-radius: 6px;
  padding: 16px;
  overflow-x: auto;
  margin: 16px 0;
}

.blog-post-body pre code {
  padding: 0;
  background: none;
  border: none;
  color: var(--text);
}

.blog-post-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 0.92rem;
}

.blog-post-body th,
.blog-post-body td {
  padding: 8px 12px;
  border: 1px solid var(--border);
  text-align: left;
  color: var(--text-secondary);
}

.blog-post-body th {
  background: var(--bg-alt);
  font-weight: 700;
  color: var(--text);
}

.blog-post-body table img {
  max-width: 200px;
  margin: 4px 0;
}

.blog-post-body hr {
  border: none;
  border-top: 1px solid var(--border-light);
  margin: 32px 0;
}

/* Math rendering */
.math-display {
  overflow-x: auto;
  padding: 12px 0;
  margin: 16px 0;
  text-align: center;
}

.math-inline {
  display: inline;
}

.math-error {
  color: var(--primary);
  font-family: monospace;
  font-size: 0.88em;
}

/* ===== Footer ===== */
.footer {
  padding: 28px 0;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-light);
  font-size: 0.88rem;
  background: var(--bg);
  transition: background 0.3s, border-color 0.3s;
}

.footer a {
  color: var(--text-light);
}

.footer a:hover {
  color: var(--contrary);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--nav-dropdown-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 16px 24px;
    border-bottom: 1px solid var(--border);
    gap: 12px;
  }

  .nav-links.open {
    display: flex;
  }

  .about-grid {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 24px;
  }

  .portrait-wrapper {
    display: flex;
    justify-content: center;
  }

  .portrait-wrapper img {
    width: 160px;
    height: 160px;
  }

  .social-links {
    justify-content: center;
  }

  .about-bio {
    text-align: left;
  }

  .pub-entry {
    grid-template-columns: 1fr;
  }

  .pub-thumb {
    width: 100%;
    height: 180px;
  }

  .project-card {
    grid-template-columns: 1fr;
  }

  .project-thumb {
    width: 100%;
    height: auto;
    aspect-ratio: 16 / 10;
  }

  .news-list li {
    flex-direction: column;
    gap: 2px;
  }

  .news-date {
    min-width: unset;
  }

  .section {
    padding: 48px 0;
  }

  #about {
    padding-top: 88px;
  }

  .section-title {
    font-size: 1.4rem;
    margin-bottom: 24px;
  }

  /* Experience timeline */
  .exp-list::before {
    display: none;
  }

  .exp-entry::after {
    display: none;
  }

  .exp-entry {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .exp-date {
    text-align: left;
  }

  .exp-info {
    padding-left: 0;
  }

  /* Blog preview */
  .blog-preview-item {
    flex-wrap: wrap;
    gap: 4px 12px;
  }

  .blog-preview-date {
    min-width: unset;
  }

  .blog-preview-tag {
    order: -1;
  }

  .blog-page-header {
    padding-top: 88px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .about-name {
    font-size: 1.6rem;
  }

  .social-links a {
    padding: 4px 10px;
    font-size: 0.82rem;
  }

  .pub-links a {
    font-size: 0.75rem;
    padding: 2px 8px;
  }

  .nav-right {
    gap: 10px;
  }
}