/* ============================================================
   Zihan Su Academic Homepage
   Template direction: compact handwritten academic profile
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Caveat:wght@400;600;700&family=Source+Serif+4:ital,opsz,wght@0,8..60,300;0,8..60,400;0,8..60,600;1,8..60,300;1,8..60,400&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg: #f8f7f4;
  --grid-color: rgba(0, 0, 0, .055);
  --text: #1a1a1a;
  --text-muted: #666;
  --text-light: #999;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --highlight-bg: #fef9c3;
  --highlight-border: #f59e0b;
  --border: #d4d0c8;
  --tag-bg: #f0ede8;
  --tag-border: #d4d0c8;
  --award-color: #b45309;
  --max-width: 920px;
  --font-serif: 'Source Serif 4', Georgia, 'Songti SC', 'Noto Serif CJK SC', serif;
  --font-hand: 'Caveat', cursive;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  color: var(--text);
  background-color: var(--bg);
  background-image:
    linear-gradient(var(--grid-color) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-color) 1px, transparent 1px);
  background-size: 28px 28px;
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.75;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color .15s;
}

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

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 32px 80px;
}

.site-header {
  margin-bottom: 36px;
}

.header-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}

.site-header h1 {
  margin-bottom: 10px;
  font-family: var(--font-hand);
  font-size: 3.4rem;
  font-weight: 700;
  letter-spacing: -.5px;
  line-height: 1.1;
}

.lang-toggle {
  min-width: 58px;
  margin-top: 6px;
  padding: 5px 10px;
  border: 1.5px solid var(--border);
  border-radius: 4px;
  background: rgba(255, 255, 255, .6);
  color: var(--text);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 500;
  transition: border-color .15s, background .15s, color .15s;
}

.lang-toggle:hover {
  border-color: var(--accent);
  background: rgba(255, 255, 255, .9);
  color: var(--accent);
}

.site-header .tagline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .02em;
  line-height: 1.8;
}

.site-header .tagline-icon {
  flex: 0 0 auto;
  color: var(--text);
  font-family: "Apple Color Emoji", "Segoe UI Emoji", "Noto Color Emoji", sans-serif;
  font-size: 1.05rem;
  line-height: 1;
}

hr.section-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 28px 0;
}

hr.unseen-section-divider {
  border: none;
  margin: 28px 0;
}

.bio-section {
  display: flex;
  gap: 32px;
  align-items: flex-start;
  margin-bottom: 24px;
}

.bio-avatar {
  width: 202px;
  flex-shrink: 0;
}

.bio-avatar img {
  display: block;
  width: 170px;
  height: 220px;
  margin: 0 auto;
  border: 2px solid var(--border);
  border-radius: 8px;
  object-fit: cover;
  object-position: center top;
  background: rgba(255, 255, 255, .6);
}

.avatar-placeholder {
  width: 170px;
  height: 220px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--border);
  border-radius: 8px;
  background: var(--tag-bg);
  color: var(--text-muted);
  font-family: var(--font-hand);
  font-size: 2rem;
}

.bio-text p {
  margin-bottom: 12px;
  font-size: .97rem;
}

.bio-text p:last-child {
  margin-bottom: 0;
}

.profile-details {
  margin: 10px 0 12px;
}

.profile-details summary {
  color: var(--text-muted);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: .78rem;
  user-select: none;
}

.profile-details summary:hover {
  color: var(--accent);
}

.profile-details-body {
  margin-top: 10px;
  color: var(--text-muted);
  font-size: .93rem;
  line-height: 1.75;
}

.profile-details-body p {
  font-size: inherit;
}

.profile-details-body p:empty {
  display: none;
}

.highlight-box {
  margin-top: 14px;
  padding: 12px 16px;
  border-left: 3.5px solid var(--highlight-border);
  border-radius: 2px;
  background: var(--highlight-bg);
  color: #78350f;
  font-size: .93rem;
  font-weight: 600;
  line-height: 1.6;
}

.social-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin: 12px 0 0;
}

.social-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 36px;
  padding: 6px 11px;
  border: 1.5px solid var(--border);
  border-radius: 4px;
  background: rgba(255, 255, 255, .6);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: .74rem;
  font-weight: 500;
  letter-spacing: .01em;
  text-decoration: none;
  transition: border-color .15s, background .15s, color .15s;
}

a.social-btn:hover {
  border-color: var(--accent);
  background: rgba(255, 255, 255, .9);
  color: var(--accent);
  text-decoration: none;
}

.social-btn img {
  width: 19px;
  height: 19px;
  display: block;
  flex: 0 0 auto;
  object-fit: contain;
}

.social-btn img.round-icon {
  border-radius: 50%;
}

.section-title {
  margin-bottom: 20px;
  color: var(--text);
  font-family: var(--font-hand);
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.1;
}

.news-list,
.edu-list,
.exp-list,
.pub-list,
.honors-other {
  list-style: none;
}

.news-item {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 0 18px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: .93rem;
}

.news-item:first-child {
  border-top: 1px solid var(--border);
}

.news-date {
  padding-top: 2px;
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .71rem;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.news-content {
  color: var(--text);
  font-weight: 400;
  line-height: 1.6;
}

.news-content strong {
  font-weight: 700;
}

.news-hidden {
  display: none;
}

.news-toggle {
  margin-top: 12px;
  padding: 6px 16px;
  border: 1.5px solid var(--border);
  border-radius: 4px;
  background: none;
  color: var(--text-muted);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: .74rem;
  transition: border-color .15s, color .15s;
}

.news-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.edu-item {
  display: grid;
  grid-template-columns: 80px 25% 1fr;
  gap: 0 14px;
  align-items: center;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
}

.edu-item:first-child {
  border-top: 1px solid var(--border);
}

.edu-years {
  padding-top: 3px;
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .71rem;
  letter-spacing: .04em;
  line-height: 1.5;
}

.edu-logo {
  width: 92%;
  max-height: 82px;
  display: block;
  justify-self: center;
  margin-top: 2px;
  border-radius: 4px;
  object-fit: contain;
}

.edu-logo-wide {
  width: 96%;
  max-height: 66px;
}

.edu-content .school {
  font-size: .97rem;
  font-weight: 600;
}

.edu-content .dept {
  color: var(--text-muted);
  font-size: .86rem;
}

.edu-content .degree {
  color: var(--text-muted);
  font-size: .86rem;
  font-style: italic;
}

.exp-item {
  display: grid;
  grid-template-columns: 96px 170px 1fr;
  gap: 0 14px;
  align-items: center;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}

.exp-item:first-child {
  border-top: 1px solid var(--border);
}

.exp-period {
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .04em;
  line-height: 1.5;
}

.exp-logo {
  width: 86%;
  max-height: 72px;
  display: block;
  justify-self: center;
  margin-top: 2px;
  border-radius: 4px;
  object-fit: contain;
}

.exp-logo-large {
  width: 88%;
  max-height: 64px;
}

.exp-content .org {
  font-size: .97rem;
  font-weight: 600;
}

.exp-content .role {
  color: var(--text-muted);
  font-size: .87rem;
}

.pub-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}

.pub-item:first-child {
  border-top: 1px solid var(--border);
}

.pub-thumb {
  width: 280px;
  flex-shrink: 0;
}

.pub-thumb img {
  width: 280px;
  height: auto;
  display: block;
  border: 1px solid var(--border);
  border-radius: 5px;
  background: rgba(255, 255, 255, .52);
  cursor: zoom-in;
  transition: transform .3s ease;
}

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

.image-lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 32px;
  background: rgba(20, 18, 14, .78);
}

.image-lightbox.is-open {
  display: flex;
}

.image-lightbox img {
  max-width: min(1120px, 94vw);
  max-height: 88vh;
  border: 1px solid rgba(255, 255, 255, .32);
  border-radius: 6px;
  background: #fff;
  box-shadow: 0 22px 70px rgba(0, 0, 0, .4);
  object-fit: contain;
}

.image-lightbox-close {
  position: fixed;
  top: 18px;
  right: 20px;
  width: 38px;
  height: 38px;
  border: 1px solid rgba(255, 255, 255, .38);
  border-radius: 50%;
  background: rgba(255, 255, 255, .12);
  color: #fff;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 1.25rem;
  line-height: 1;
}

.image-lightbox-close:hover {
  background: rgba(255, 255, 255, .22);
}

.pub-thumb-placeholder {
  width: 280px;
  height: 112px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: 5px;
  background: var(--tag-bg);
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .65rem;
  text-align: center;
}

.pub-body {
  min-width: 0;
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 5px;
}

.pub-title {
  color: var(--text);
  font-size: .97rem;
  font-weight: 600;
  line-height: 1.5;
}

.pub-authors {
  color: var(--text-muted);
  font-size: .85rem;
  line-height: 1.55;
}

.pub-authors .self {
  color: var(--text);
  font-weight: 600;
  text-decoration: underline;
  text-decoration-style: dotted;
}

.pub-venue {
  color: var(--text-muted);
  font-size: .87rem;
  font-style: italic;
}

.pub-venue .venue-name {
  color: var(--text);
  font-style: normal;
  font-weight: 600;
}

.pub-award {
  color: var(--award-color);
  font-size: .82rem;
  font-weight: 600;
}

.pub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}

.pub-link {
  padding: 3px 10px;
  border: 1px solid var(--tag-border);
  border-radius: 3px;
  background: var(--tag-bg);
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: .71rem;
  text-decoration: none;
  transition: border-color .15s, color .15s;
}

.pub-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}

.honors-other li {
  display: flex;
  gap: 14px;
  padding: 9px 0;
  border-bottom: 1px solid var(--border);
  font-size: .9rem;
}

.honors-other li:first-child {
  border-top: 1px solid var(--border);
}

.honors-other .h-year {
  width: 44px;
  flex-shrink: 0;
  padding-top: 2px;
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .71rem;
}

.site-footer {
  margin-top: 60px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text-light);
  font-family: var(--font-mono);
  font-size: .72rem;
  text-align: center;
}

@media (max-width: 700px) {
  .container {
    padding: 36px 18px 60px;
  }

  .site-header h1 {
    font-size: 2.6rem;
  }

  .site-header .tagline {
    align-items: flex-start;
    max-width: 100%;
  }

  .bio-section {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .bio-avatar img,
  .avatar-placeholder {
    width: 164px;
    height: 212px;
  }

  .bio-avatar {
    width: 202px;
  }

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

  .news-item {
    grid-template-columns: 1fr;
    gap: 3px;
    padding: 14px 0;
  }

  .edu-item,
  .exp-item {
    grid-template-columns: 64px 1fr;
  }

  .edu-logo,
  .exp-logo {
    display: none;
  }

  .pub-item {
    flex-direction: column;
  }

  .pub-thumb,
  .pub-thumb img {
    width: 100%;
  }
}

@media (max-width: 400px) {
  .social-btn {
    width: 100%;
    justify-content: center;
  }
}