/* ============================================================
   Color tokens — change here to restyle the whole site
   ============================================================ */
:root {
  --blue:         #1B75BB;
  --blue-dark:    #145a8f;
  --blue-light:   #e8f2fa;
  --yellow:       #F5C518;
  --yellow-dark:  #d4a80e;
  --white:        #ffffff;
  --dark:         #1e2b3c;
  --text:         #333333;
  --muted:        #6c757d;
  --bg:           #f5f7fa;
  --border:       #dee2e6;
  --shadow:       0 2px 12px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 6px 24px rgba(0, 0, 0, 0.14);
  --radius:       8px;
  --radius-lg:    12px;
  --nav-height:   68px;
  --font:         -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* ============================================================
   Reset & base
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: var(--font); color: var(--text); background: var(--white); line-height: 1.6; }
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--blue-dark); }
img { max-width: 100%; display: block; }
h1, h2, h3, h4 { line-height: 1.3; color: var(--dark); }

/* ============================================================
   Navigation
   ============================================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: var(--white);
  border-bottom: 3px solid var(--yellow);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.06);
  gap: 1rem;
}

.navbar-brand img { height: 44px; width: auto; }

.navbar-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  flex: 1;
  justify-content: center;
}

.navbar-links a {
  color: var(--dark);
  font-weight: 500;
  font-size: 0.92rem;
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius);
  transition: background 0.18s, color 0.18s;
}

.navbar-links a:hover,
.navbar-links a.active {
  background: var(--blue);
  color: var(--white);
}

.navbar-ugent img { height: 38px; width: auto; }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 6px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--dark);
  border-radius: 2px;
  transition: all 0.25s;
}

.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   Page wrapper
   ============================================================ */
.page-content { margin-top: var(--nav-height); }

/* ============================================================
   Welcome — cozy split: text + portrait photo
   ============================================================ */
.welcome {
  background: var(--white);
  border-bottom: 3px solid var(--yellow);
  padding: 3.5rem 2rem;
}

.welcome-grid {
  display: grid;
  grid-template-columns: 3fr 2fr;
  gap: 3rem;
  align-items: center;
  max-width: 1100px;
  margin: 0 auto;
}

.welcome-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 0.4rem;
}

.welcome-text h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--dark);
  line-height: 1.2;
  margin-bottom: 0.2rem;
}

.welcome-univ {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 1.25rem;
}

.welcome-body {
  color: var(--text);
  font-size: 0.97rem;
  line-height: 1.85;
  margin-bottom: 1.5rem;
}

.welcome-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  background: var(--blue-light);
  color: var(--blue);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.28rem 0.75rem;
  border-radius: 20px;
  border: 1px solid rgba(27, 117, 187, 0.2);
}

.welcome-photo {
  aspect-ratio: 972 / 1249;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-hover);
  border: 3px solid var(--yellow);
}

.welcome-photo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

/* ============================================================
   Sections
   ============================================================ */
.section { padding: 4rem 2rem; }
.section-alt { background: var(--bg); }

.container { max-width: 1100px; margin: 0 auto; }

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--blue);
  padding-bottom: 0.4rem;
  border-bottom: 3px solid var(--yellow);
  display: inline-block;
  margin-bottom: 0.5rem;
}

.section-subtitle { color: var(--muted); margin-bottom: 2rem; }

/* ============================================================
   Cards: mission & placeholder
   ============================================================ */
.mission-card {
  background: var(--white);
  border-left: 4px solid var(--blue);
  border-radius: var(--radius);
  padding: 1.75rem 2rem;
  box-shadow: var(--shadow);
  font-size: 1.04rem;
  line-height: 1.85;
}

.placeholder-card {
  background: var(--blue-light);
  border: 2px dashed var(--blue);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
  color: var(--muted);
}

.placeholder-card .placeholder-icon { font-size: 2rem; margin-bottom: 0.5rem; }

/* ============================================================
   Page header (inner pages)
   ============================================================ */
.page-header {
  background: linear-gradient(135deg, var(--blue) 0%, var(--blue-dark) 100%);
  padding: 3.5rem 2rem;
  text-align: center;
}

.page-header h1 { color: var(--white); font-size: 2.2rem; margin-bottom: 0.4rem; }
.page-header p  { color: rgba(255, 255, 255, 0.8); font-size: 1rem; }

/* ============================================================
    People
    ============================================================ */
.role-section { margin-bottom: 3rem; }

.role-section-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-bottom: 3rem;
}

.role-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--blue);
  padding: 0.3rem 0.85rem;
  background: var(--blue-light);
  border-radius: var(--radius);
  display: inline-block;
  margin-bottom: 1.5rem;
}

.people-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  align-items: stretch;
}

.person-card {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  text-align: left;
  padding: 1.25rem;
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s;
}

.person-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); }

.person-card-header {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  margin-bottom: 1rem;
}

.person-photo {
  width: 76px;
  height: 76px;
  border-radius: 50%;
  overflow: hidden;
  background: var(--blue);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 3px solid var(--blue-light);
  flex-shrink: 0;
}

.person-photo img { width: 100%; height: 100%; object-fit: cover; }

.person-initials {
  color: var(--white);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.04em;
}

.person-identity { min-width: 0; }
.person-name  { font-size: 0.95rem; font-weight: 700; color: var(--dark); margin-bottom: 0.1rem; }
.person-role  { font-size: 0.78rem; color: var(--muted); margin-bottom: 0.4rem; }

.person-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.person-link {
  display: inline-flex;
  color: var(--blue);
  background: var(--blue-light);
  border-radius: 999px;
  padding: 0.12rem 0.5rem;
  font-size: 0.72rem;
  font-weight: 600;
}

.person-link:hover { color: var(--white); background: var(--blue); }

.person-profile { margin-bottom: 0.9rem; }

.person-profile-label {
  color: var(--blue);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  margin-bottom: 0.3rem;
  text-transform: uppercase;
}

.person-research {
  color: var(--text);
  font-size: 0.84rem;
  line-height: 1.6;
}

.person-expertise {
  border-top: 1px solid var(--border);
  margin-top: auto;
  padding-top: 0.8rem;
}

.person-expertise-list {
  list-style: disc;
  padding-left: 1.1rem;
}

.person-expertise-list li {
  color: var(--text);
  font-size: 0.78rem;
  line-height: 1.45;
  margin-bottom: 0.25rem;
}

.person-expertise-empty {
  color: var(--muted);
  font-size: 0.78rem;
  font-style: italic;
}

/* Professor variant */
.person-card.professor .person-photo {
  width: 84px;
  height: 84px;
  background: var(--blue-dark);
  border: 3px solid var(--yellow);
}

.person-card.professor .person-name { font-size: 1.05rem; }
.person-card.professor .person-role { font-size: 0.82rem; color: var(--blue); font-weight: 500; }

/* ============================================================
   Research grid
   ============================================================ */
.research-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 2rem;
  margin-top: 3.5rem;
}

.research-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  text-align: center;
  position: relative;
  overflow: visible;
  padding: 2.75rem 1.75rem 2rem;
  background: var(--white);
  border-radius: 1.25rem;
  box-shadow: var(--shadow);
  color: var(--dark);
  border: 2px solid transparent;
  transition: transform 0.22s, box-shadow 0.22s, border-color 0.22s, background 0.22s;
}

.research-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--blue);
  background: var(--blue-light);
  color: var(--blue);
}

.research-icon {
  position: absolute;
  top: -32px;
  left: 50%;
  transform: translateX(-50%);
  width: 64px;
  height: 64px;
  background: white;
  border-radius: 50%;
  box-shadow: 0 2px 10px rgba(0,0,0,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
}

.research-icon img { width: 58%; height: 58%; object-fit: contain; }

.research-card h3 { font-size: 0.97rem; font-weight: 700; margin-bottom: 0.5rem; color: var(--blue-dark, #1a2e4a); }

.research-card-subtitle {
  font-size: 0.78rem;
  color: var(--muted);
  font-style: italic;
  margin-top: 0.2rem;
  display: none;
}

.research-card-summary {
  font-size: 0.86rem;
  color: #555;
  line-height: 1.6;
  margin-top: 0.75rem;
  margin-bottom: 0;
}

.research-card:hover .research-card-subtitle,
.research-card:hover .research-card-summary { color: inherit; }

.research-arrow {
  margin-top: auto;
  padding-top: 1.25rem;
  font-size: 0.82rem;
  color: var(--blue);
  opacity: 0;
  transition: opacity 0.2s;
}

.research-card:hover .research-arrow { opacity: 1; }

/* ============================================================
   Research detail page
   ============================================================ */
.research-detail-header {
  background: linear-gradient(135deg, var(--blue), var(--blue-dark));
  padding: 4rem 2rem 3rem;
  text-align: center;
}

.research-detail-icon {
  width: 110px;
  height: 110px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  padding: 1rem;
}

.research-detail-icon img { width: 100%; height: 100%; object-fit: contain; filter: brightness(0) invert(1); }

.research-detail-header h1 { color: var(--white); font-size: 2rem; margin-bottom: 0.5rem; }
.research-detail-subtitle   { color: rgba(255, 255, 255, 0.82); font-size: 1.05rem; }

.research-detail-content { max-width: 800px; margin: 3rem auto; padding: 0 2rem 4rem; }

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: 2rem;
  font-size: 0.92rem;
}

.back-link:hover { color: var(--blue-dark); }

/* ============================================================
   Publications
   ============================================================ */
.pub-link-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 1.4rem 1.5rem;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border-left: 4px solid var(--yellow);
  margin-bottom: 1rem;
  color: var(--dark);
  transition: box-shadow 0.2s, transform 0.2s;
}

.pub-link-card:hover { box-shadow: var(--shadow-hover); transform: translateX(3px); color: var(--dark); }

.pub-link-icon { font-size: 1.8rem; flex-shrink: 0; }
.pub-link-text h3 { font-size: 0.98rem; margin-bottom: 0.2rem; }
.pub-link-text p  { font-size: 0.82rem; color: var(--muted); }

.publications-panel {
  background: var(--bg);
  border-radius: var(--radius-lg);
  margin-top: 2rem;
  padding: 2rem;
}

.publications-panel-header h2 {
  color: var(--blue);
  font-size: 1.35rem;
  margin-bottom: 0.4rem;
}

.publications-panel-header p {
  color: var(--muted);
  font-size: 0.92rem;
  margin-bottom: 1.25rem;
}

.publication-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 1rem;
}

.publication-filter {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--dark);
  cursor: pointer;
  font: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.45rem 0.8rem;
  transition: background 0.18s, border-color 0.18s, color 0.18s;
}

.publication-filter:hover,
.publication-filter.active {
  background: var(--blue);
  border-color: var(--blue);
  color: var(--white);
}

.publication-year-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-bottom: 1rem;
}

.publication-year-tab {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0.35rem 0.65rem;
  transition: background 0.18s, border-color 0.18s, color 0.18s;
}

.publication-year-tab:hover,
.publication-year-tab.active {
  background: var(--yellow);
  border-color: var(--yellow-dark);
  color: var(--dark);
}

.publication-status {
  color: var(--muted);
  font-size: 0.86rem;
  margin-bottom: 1rem;
}

.publication-list {
  display: grid;
  gap: 1rem;
}

.publication-card {
  background: var(--white);
  border-left: 4px solid var(--yellow);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.2rem 1.35rem;
}

.publication-meta {
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  margin-bottom: 0.45rem;
  text-transform: uppercase;
}

.publication-card h3 {
  font-size: 1rem;
  margin-bottom: 0.45rem;
}

.publication-authors,
.publication-source {
  color: var(--muted);
  font-size: 0.83rem;
  line-height: 1.55;
}

.publication-source { margin-top: 0.25rem; }

.publication-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 0.8rem;
}

.publication-tag {
  background: var(--blue-light);
  border: 1px solid rgba(27, 117, 187, 0.18);
  border-radius: 999px;
  color: var(--blue);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.18rem 0.55rem;
}

.publication-empty {
  background: var(--white);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  color: var(--muted);
  padding: 1rem;
}

/* ============================================================
   Contact
   ============================================================ */
.contact-grid { display: flex; gap: 2.5rem; flex-wrap: wrap; align-items: flex-start; }

.contact-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 2.5rem;
  min-width: 280px;
}

.contact-photo {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  background: var(--blue-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
  border: 4px solid var(--yellow);
  overflow: hidden;
}

.contact-photo img { width: 100%; height: 100%; object-fit: cover; }
.contact-photo .person-initials { font-size: 1.5rem; }

.contact-card h2 { font-size: 1.4rem; margin-bottom: 0.2rem; }
.contact-role { color: var(--blue); font-weight: 500; font-size: 0.92rem; margin-bottom: 1.5rem; }

.contact-item {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 0.75rem;
  font-size: 0.92rem;
}

.contact-item-icon {
  width: 34px;
  height: 34px;
  background: var(--blue-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  flex-shrink: 0;
}

/* ============================================================
   Footer
   ============================================================ */
footer {
  background: var(--bg);
  border-top: 3px solid var(--yellow);
  color: var(--muted);
  padding: 2rem;
  text-align: center;
  font-size: 0.83rem;
}

.footer-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 1rem;
}

.footer-logos img { height: 38px; opacity: 0.75; }
footer a { color: var(--blue); }
footer a:hover { color: var(--blue-dark); }

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

  .navbar-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0; right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 1rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-bottom: 2px solid var(--yellow);
    gap: 0;
  }

  .navbar-links.open { display: flex; }
  .navbar-links li { width: 100%; }
  .navbar-links a { display: block; padding: 0.6rem 1rem; border-radius: var(--radius); }

  .welcome-grid { grid-template-columns: 1fr; }
  .welcome-photo { order: -1; }
  .welcome-text h1 { font-size: 1.6rem; }

  .section { padding: 2.5rem 1rem; }

  .role-section-row { grid-template-columns: 1fr; }
  .people-grid { grid-template-columns: 1fr; }
  .person-card-header { align-items: flex-start; }
  .research-grid { grid-template-columns: 1fr; }

  .publications-panel { padding: 1.25rem; }
  .pub-link-card { align-items: flex-start; }

  .contact-grid { flex-direction: column; }
}