/* === BASE RESET & TYPOGRAPHY === */
:root {
  --color-text: #1a1a1a;
  --color-text-muted: #5a5a5a;
  --color-text-subtle: #8a8a8a;
  --color-bg: #fafafa;
  --color-surface: #fff;
  --color-border: #e8e8e8;
  --color-accent: #2d2d2d;
  --color-accent-hover: #000;
  --color-highlight: #eff6ff;
  --color-link-hover: #f0f4ff;
  --color-blue: #1d4ed8;
  --color-blue-light: #3b82f6;
  --color-blue-muted: #93c5fd;
  --font-display: 'Caveat Brush', cursive;
  --font-body: 'Source Serif 4', Georgia, serif;
  --font-ui: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
}

* {
  box-sizing: border-box;
}

body {
  font-family: var(--font-body);
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* === LINKS === */
a {
  color: inherit;
  text-decoration: none;
  transition: all var(--transition-fast);
}

a:hover {
  color: var(--color-accent-hover);
}

/* === LAYOUT === */
.container {
  display: flex;
  min-height: 100vh;
}

main {
  flex: 1;
  padding: 4rem 3rem;
  max-width: 920px;
  margin: 0 auto;
}

/* === HEADER === */
.header {
  display: flex;
  align-items: flex-start;
  margin-bottom: 2rem;
  gap: 2rem;
}

.profile-column {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 160px;
  min-width: 160px;
}

.profile-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 1rem;
  border: 3px solid var(--color-border);
  transition: transform var(--transition-base);
}

.profile-photo:hover {
  transform: scale(1.02);
}

.header > div:not(.profile-column) {
  flex: 1;
  padding-top: 0.5rem;
}

h1 {
  font-family: var(--font-display);
  font-size: 2.8rem;
  margin: 0 0 0.25rem 0;
  font-weight: 400;
  letter-spacing: -0.5px;
  color: var(--color-text);
}

.name-chinese {
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--color-text-muted);
  letter-spacing: 0.02em;
  vertical-align: middle;
}

.title-tag {
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-blue);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin: 0 0 0.5rem 0;
  display: block;
}

/* === PERSONAL LINKS === */
.personal-links-row {
  display: flex;
  flex-direction: row;
  gap: 0.6rem;
  align-items: center;
  margin: 0.75rem 0;
  flex-wrap: wrap;
}

.personal-link-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-ui);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-decoration: none;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  width: 2.25rem;
  height: 2.25rem;
  transition: all var(--transition-fast);
}

.personal-link-bar:hover {
  background: var(--color-blue);
  color: white;
  border-color: var(--color-blue);
}

.personal-link-bar .icon {
  font-size: 0.75em;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

/* === ABOUT === */
.about-me {
  margin-top: 1rem;
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.8;
}

.about-me p {
  margin: 0 0 0.75rem 0;
}

/* === HIGHLIGHTS === */
.highlight-blue-yellow {
  font-weight: 600;
  color: var(--color-text);
  border-bottom: 2px solid var(--color-blue);
  padding-bottom: 1px;
  background: none;
  transition: border-color var(--transition-fast);
}

.highlight-blue-yellow:hover {
  border-color: var(--color-blue-light);
  color: var(--color-blue);
}

.highlight-stroke,
.highlight-institution,
.highlight-person-underline {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 1px;
  background: none;
  transition: border-color var(--transition-fast);
}

.highlight-stroke:hover,
.highlight-institution:hover,
.highlight-person-underline:hover {
  border-color: var(--color-text-muted);
  background: none;
}

.highlight-interest {
  font-weight: 600;
  color: var(--color-text);
  background: none;
  border-bottom: 2px solid var(--color-blue);
  padding-bottom: 1px;
}

.highlight-interest-secondary {
  font-style: italic;
  color: var(--color-text-muted);
}

/* === SECTION TITLES === */
.section-title {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-top: 3rem;
  margin-bottom: 1.5rem;
  color: var(--color-text-subtle);
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-border);
}

/* === RECENT UPDATES === */
.recent-updates-section {
  margin: 0;
}

.recent-updates-section .section-title {
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.updates-scroll-container {
  padding: 0;
}

.update-item {
  display: flex;
  gap: 1rem;
  padding: 0.3rem 0;
  align-items: baseline;
  font-size: 0.9rem;
  font-family: var(--font-ui);
}

.update-date {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-text-subtle);
  min-width: 60px;
}

.update-badge {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-ui);
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  padding: 0.1rem 0.45rem;
  border-radius: 3px;
  margin-right: 0.3rem;
  vertical-align: middle;
}

.update-badge.paper {
  background: #eff6ff;
  color: var(--color-blue);
  border: 1px solid #bfdbfe;
}

.update-badge.industry {
  background: #f0fdf4;
  color: #16a34a;
  border: 1px solid #bbf7d0;
}

.update-badge.award {
  background: #fffbeb;
  color: #d97706;
  border: 1px solid #fde68a;
}

.company-logo {
  height: 1em;
  width: auto;
  vertical-align: baseline;
  margin: 0 0.2rem;
  opacity: 0.8;
}

/* === INDUSTRY SECTION === */
.industry-section {
  margin-top: 0;
}

.industry-description {
  margin-bottom: 1.5rem;
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.8;
}

.industry-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  transition: border-color var(--transition-base);
}

.industry-card:hover {
  border-color: var(--color-blue-muted);
}

.industry-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

.industry-card-title {
  font-family: var(--font-ui);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
  margin: 0 0 0.2rem 0;
}

.industry-card-subtitle {
  font-family: var(--font-ui);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin: 0;
}

.industry-card-date {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  color: var(--color-text-subtle);
  white-space: nowrap;
  padding-top: 0.1rem;
}

.industry-bullets {
  margin: 0.5rem 0 0 0;
  padding-left: 1.2rem;
  font-size: 0.9rem;
  font-family: var(--font-ui);
  color: var(--color-text-muted);
  line-height: 1.8;
}

.industry-bullets li {
  margin-bottom: 0.3rem;
}

.industry-bullets strong {
  color: var(--color-text);
  font-weight: 600;
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.75rem;
}

.tag {
  font-family: var(--font-ui);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 0.2rem 0.55rem;
  background: var(--color-highlight);
  color: var(--color-blue);
  border-radius: 3px;
  letter-spacing: 0.3px;
}

/* === RESEARCH SECTION === */
.research-section {
  margin-top: 0;
}

.research-description {
  margin-bottom: 1.5rem;
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.8;
}

.research-item {
  display: flex;
  align-items: flex-start;
  margin-bottom: 1rem;
  padding: 1rem;
  background: var(--color-surface);
  border-radius: 4px;
  border: 1px solid var(--color-border);
  transition: border-color var(--transition-base);
}

.research-item:hover {
  border-color: var(--color-blue-muted);
}

.research-image {
  flex-shrink: 0;
  margin-right: 1.25rem;
  width: 200px;
}

.research-image img {
  width: 100%;
  height: auto;
  border-radius: 3px;
  object-fit: cover;
  filter: grayscale(5%);
  transition: filter var(--transition-base);
}

.research-item:hover .research-image img {
  filter: grayscale(0%);
}

/* CSS-only paper thumbnails */
.paper-thumb {
  width: 100%;
  height: 130px;
  border-radius: 3px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: space-between;
  padding: 0.75rem;
  position: relative;
  overflow: hidden;
  background: var(--thumb-bg, linear-gradient(135deg, #1d4ed8, #3b82f6));
  transition: filter var(--transition-base);
  filter: saturate(0.85);
}

.research-item:hover .paper-thumb {
  filter: saturate(1);
}

.paper-thumb::before {
  content: '';
  position: absolute;
  top: -20px;
  right: -20px;
  width: 90px;
  height: 90px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
}

.paper-thumb::after {
  content: '';
  position: absolute;
  bottom: -15px;
  left: 20px;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: rgba(255,255,255,0.05);
}

.thumb-venue {
  font-family: var(--font-ui);
  font-size: 0.7rem;
  font-weight: 800;
  color: rgba(255,255,255,0.95);
  background: rgba(0,0,0,0.2);
  padding: 0.15rem 0.45rem;
  border-radius: 3px;
  letter-spacing: 1px;
  text-transform: uppercase;
  position: relative;
  z-index: 1;
}

.thumb-label {
  font-family: var(--font-ui);
  font-size: 0.65rem;
  font-weight: 500;
  color: rgba(255,255,255,0.75);
  position: relative;
  z-index: 1;
  line-height: 1.3;
  max-width: 90%;
}

/* Paper thumb color presets */
.thumb-hpca {
  --thumb-bg: linear-gradient(145deg, #1e3a8a 0%, #1d4ed8 60%, #3b82f6 100%);
}
.thumb-asplos {
  --thumb-bg: linear-gradient(145deg, #0f172a 0%, #1e3a5f 60%, #1d4ed8 100%);
}
.thumb-isca {
  --thumb-bg: linear-gradient(145deg, #134e4a 0%, #0f766e 60%, #14b8a6 100%);
}
.thumb-micro {
  --thumb-bg: linear-gradient(145deg, #3b0764 0%, #6d28d9 60%, #8b5cf6 100%);
}
.thumb-ics {
  --thumb-bg: linear-gradient(145deg, #0c4a6e 0%, #0369a1 60%, #0ea5e9 100%);
}
.thumb-vldb {
  --thumb-bg: linear-gradient(145deg, #1c1917 0%, #44403c 60%, #78716c 100%);
}
.thumb-iiswc {
  --thumb-bg: linear-gradient(145deg, #14532d 0%, #15803d 60%, #4ade80 100%);
}
.thumb-pact {
  --thumb-bg: linear-gradient(145deg, #7f1d1d 0%, #b91c1c 60%, #f87171 100%);
}

.research-content {
  flex: 1;
}

.research-content h3 {
  font-family: var(--font-body);
  margin: 0 0 0.25rem 0;
  font-size: 0.97rem;
  font-weight: 600;
  color: var(--color-text);
  line-height: 1.35;
}

.research-authors {
  margin-bottom: 0.15rem;
  font-family: var(--font-ui);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

.research-authors strong {
  color: var(--color-text);
}

.research-venue {
  margin-bottom: 0.4rem;
  font-family: var(--font-ui);
  font-size: 0.75rem;
  color: var(--color-text-subtle);
  letter-spacing: 0.3px;
  font-weight: 400;
}

.venue-link {
  color: var(--color-blue);
  font-weight: 700;
  border-bottom: none;
  letter-spacing: 0.5px;
  transition: color var(--transition-fast);
}

.venue-link:hover {
  color: var(--color-blue-light);
}

.research-venue .venue-note {
  color: var(--color-text-subtle);
  font-weight: 400;
}

/* talk link variant — slightly differentiated */
.link-talk {
  color: var(--color-text-muted) !important;
  border-color: var(--color-border) !important;
}

.link-talk:hover {
  background: #dc2626 !important;
  border-color: #dc2626 !important;
  color: white !important;
}

.research-content p {
  margin: 0 0 0.45rem 0;
  font-size: 0.85rem;
  line-height: 1.55;
  color: var(--color-text-muted);
}

.research-links {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  align-items: center;
  margin-top: 0.2rem;
}

.research-links a {
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 3px;
  padding: 0.2rem 0.65rem;
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.78rem;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 0.3em;
}

.research-links a:hover {
  background: var(--color-blue);
  color: white;
  border-color: var(--color-blue);
}

/* === EDUCATION SECTION === */
.education-section {
  margin-top: 0;
}

.edu-item {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--color-border);
  gap: 1rem;
}

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

.edu-content {
  flex: 1;
}

.edu-degree {
  font-family: var(--font-ui);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-text);
  margin: 0 0 0.15rem 0;
}

.edu-school {
  font-family: var(--font-ui);
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin: 0 0 0.1rem 0;
}

.edu-detail {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  color: var(--color-text-subtle);
  margin: 0;
}

.edu-date {
  font-family: var(--font-ui);
  font-size: 0.75rem;
  color: var(--color-text-subtle);
  white-space: nowrap;
}

/* === MISC === */
.misc-section {
  margin-top: 0;
}

.misc-list {
  margin: 0;
  padding-left: 1.25rem;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  line-height: 1.8;
  font-family: var(--font-ui);
}

.misc-list li {
  margin-bottom: 0.25rem;
}

/* === FOOTER === */
.copyright-footer {
  text-align: center;
  padding: 3rem 0 2rem;
  margin-top: 4rem;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-subtle);
  font-family: var(--font-ui);
  font-size: 0.75rem;
  letter-spacing: 0.5px;
}

.copyright-footer p {
  margin: 0;
}

/* === RESPONSIVE === */
@media (max-width: 800px) {
  main {
    padding: 2rem 1.5rem;
  }

  .header {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 1.5rem;
  }

  .profile-column {
    width: auto;
    min-width: auto;
  }

  .profile-photo {
    width: 130px;
    height: 130px;
  }

  h1 {
    font-size: 2.2rem;
  }

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

  .research-item {
    flex-direction: column;
    padding: 1.25rem;
  }

  .research-image {
    margin-right: 0;
    margin-bottom: 1rem;
    width: 100%;
    max-width: 280px;
  }

  .research-content h3 {
    font-size: 0.95rem;
  }

  .section-title {
    margin-top: 2rem;
  }

  .copyright-footer {
    padding: 2rem 0 1.5rem;
    margin-top: 3rem;
  }

  .edu-item {
    flex-direction: column;
    gap: 0.25rem;
  }

  .industry-card-header {
    flex-direction: column;
    gap: 0.25rem;
  }
}