/* Research topic tabs + filtered publications — adapted from legacy style.css
   for use alongside styles.css/subpages.css on research.html. */

:root {
  --penn-blue: #011F5B;
  --penn-red: #990000;
  --penn-blue-bg: #e8eef7;
  --gray-50: #f8f9fa;
  --gray-100: #f0f1f3;
  --gray-200: #e2e4e8;
  --gray-300: #c5c8d0;
  --gray-600: #6b7280;
  --gray-700: #4a4f5a;
  --gray-800: #2d3138;
  --gray-900: #1a1d23;
  --rt-radius: 8px;
}

.rt-section {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 var(--pad-x, 36px);
}

/* combined two-column layout: areas (left) + topics (right) */
.areas-topics{
  margin: 0 var(--pad-x, 36px);
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  border: 1px solid var(--line);
  border-radius: var(--r-lg, 16px);
  overflow: hidden;
}
.areas-list{
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
}
.areas-list .area{
  border-right: none !important;
  border-bottom: 1px solid var(--line) !important;
  cursor: pointer;
  padding: clamp(20px, 2.4vw, 32px);
  gap: 20px;
}
.areas-list .area:last-child{ border-bottom: none !important; }
.areas-list .area.active{ background: var(--bg-warm); }
.areas-list .area .area-num{
  font-size: clamp(28px, 3vw, 48px);
}
.areas-list .area .area-body h3{
  font-size: clamp(20px, 1.8vw, 28px);
  margin-bottom: 8px;
}
.areas-list .area .area-body p{
  font-size: 14px;
  margin-bottom: 12px;
}

.topics-list{
  padding: clamp(20px, 2.4vw, 32px);
  align-self: start;
}
.topics-list .research-category-panel{
  padding-top: 0;
}
.topics-list .research-topic-item{
  padding: 14px 0;
  row-gap: 8px;
}
.topics-list .research-topic-item:first-child{
  padding-top: 0;
}
.topics-list .research-topic-item:last-child{
  padding-bottom: 0;
  border-bottom: none;
}
.topics-list .research-topic-item h3{
  font-size: 0.98rem;
}
.topics-list .research-topic-item p{
  font-size: 0.88rem;
  line-height: 1.6;
}
.topics-list .view-pubs-btn{
  padding: 6px 14px;
  font-size: 0.8rem;
}

@media (max-width: 980px){
  .areas-topics{ grid-template-columns: 1fr; }
  .areas-list{ border-right: none; border-bottom: 1px solid var(--line); }
}

.research-category-tabs {
  display: flex;
  gap: 0;
  border-bottom: 2px solid var(--gray-200);
  margin: 32px 0 0;
  flex-wrap: wrap;
}
.research-category-tab {
  padding: 12px 24px;
  background: none;
  border: none;
  font: 600 0.95rem var(--sans, system-ui);
  color: var(--gray-600);
  cursor: pointer;
  position: relative;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: color .2s ease, border-bottom-color .3s ease;
}
.research-category-tab:hover { color: var(--penn-blue); }
.research-category-tab.active { color: var(--penn-blue); border-bottom-color: var(--penn-blue); }

.research-category-panel {
  display: none;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity .4s ease, transform .4s ease;
  padding-top: 8px;
}
.research-category-panel.active { display: block; opacity: 1; transform: translateY(0); }
.research-category-panel.fade-out { display: block; opacity: 0; transform: translateY(-12px); }

.research-topic-item {
  padding: 28px 0;
  border-bottom: 1px solid var(--gray-200);
  display: grid;
  grid-template-columns: 1fr auto;
  column-gap: 16px;
  row-gap: 12px;
  align-items: start;
}
.research-topic-item:last-child { border-bottom: none; }
.research-topic-item h3 {
  grid-row: 1; grid-column: 1;
  font-size: 1.05rem; font-weight: 700;
  color: var(--gray-900);
  margin: 0;
  align-self: center;
}
.research-topic-item p {
  grid-column: 1 / -1;
  font-size: 0.92rem; line-height: 1.7;
  color: var(--gray-700); margin: 0;
}
.view-pubs-btn {
  grid-row: 1; grid-column: 2;
  align-self: center;
  white-space: nowrap;
  padding: 8px 18px;
  border: 1.5px solid var(--penn-blue);
  border-radius: 6px;
  background: #fff;
  color: var(--penn-blue);
  font: 600 0.85rem var(--sans, system-ui);
  cursor: pointer;
  transition: all .2s ease;
}
.view-pubs-btn:hover { background: var(--penn-blue); color: #fff; }

/* Publications */
#publications-section { scroll-margin-top: 100px; }
#publications-section.highlight { animation: rt-pulse 0.8s ease; }
@keyframes rt-pulse {
  0% { background: transparent; }
  30% { background: var(--penn-blue-bg); }
  100% { background: transparent; }
}

.topic-hint { font-size: 0.95rem; color: var(--gray-700); margin: 0 0 14px; }
.topic-tabs {
  display: flex; flex-wrap: wrap; gap: 8px;
  margin-bottom: 32px; padding-bottom: 16px;
  border-bottom: 1px solid var(--gray-200);
}
.topic-tab {
  padding: 9px 18px;
  border: 1px solid var(--gray-300);
  border-radius: 20px;
  background: #fff;
  color: var(--gray-700);
  font: 500 0.98rem var(--sans, system-ui);
  cursor: pointer;
  transition: all .2s ease;
}
.topic-tab:hover { border-color: var(--penn-blue); color: var(--penn-blue); }
.topic-tab.active { background: var(--penn-blue); color: #fff; border-color: var(--penn-blue); }

#publications-container { transition: opacity .3s ease; }
#publications-container.fade-out { opacity: 0; }
.pub-year-group h3 {
  font-size: 1.45rem;
  color: var(--penn-blue);
  margin: 36px 0 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--gray-200);
}
.pub-entry {
  padding: 20px 0;
  border-bottom: 1px solid var(--gray-100);
}
.pub-entry:last-child { border-bottom: none; }
.pub-entry .pub-title {
  font-weight: 600; font-size: 1.12rem;
  line-height: 1.45;
  color: var(--gray-900); margin-bottom: 6px;
}
.pub-entry .pub-authors { font-size: 1rem; color: var(--gray-700); margin-bottom: 4px; }
.pub-entry .pub-venue  { font-size: 0.98rem; color: var(--gray-800); font-style: italic; }
.pub-entry .pub-links  { margin-top: 8px; }
.pub-entry .pub-links a {
  font-size: 0.92rem; font-weight: 600;
  margin-right: 14px; color: var(--penn-red);
}
.pub-type-badge {
  display: inline-block;
  font-size: 0.8rem; font-weight: 600;
  padding: 3px 10px; border-radius: 4px;
  background: var(--gray-100); color: var(--gray-700);
  margin-left: 8px; vertical-align: middle;
}
.pub-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.pub-tags .pub-tag {
  display: inline-block;
  font-size: 0.8rem; font-weight: 600;
  padding: 3px 12px; border-radius: 12px;
  cursor: pointer;
  transition: opacity .15s;
}
.pub-tags .pub-tag:hover { opacity: .8; }
.pub-count { font-size: 1rem; color: var(--gray-700); margin-bottom: 18px; }

.pagination { display: flex; justify-content: center; gap: 8px; margin-top: 32px; flex-wrap: wrap; }
.pagination button {
  padding: 9px 16px;
  border: 1px solid var(--gray-300);
  border-radius: var(--rt-radius);
  background: #fff;
  cursor: pointer;
  font: 500 0.95rem var(--sans, system-ui);
  transition: all .2s ease;
}
.pagination button:hover,
.pagination button.active {
  background: var(--penn-blue);
  color: #fff;
  border-color: var(--penn-blue);
}