/* ============================================================
   BISP Lab — McGovern-Inspired Design System
   ============================================================ */

/* ---- CSS Variables ---------------------------------------- */
:root {
  --dark-navy:   #0a0e1a;
  --dark-bg:     #0d1120;
  --mid-dark:    #141929;
  --darker-bg:   #111827;
  --teal:        #00b4c8;
  --teal-dark:   #0097a7;
  --teal-light:  #4dd0e1;
  --gold:        #e8c547;
  --gold-dark:   #d4a017;
  --white:       #ffffff;
  --off-white:   #f4f6f9;
  --light-gray:  #e8edf2;
  --mid-gray:    #8a9ab5;
  --text-muted:  #8a9ab5;
  --dark-text:   #1a1a2e;
  --border-dark: rgba(255,255,255,0.08);
  --border-light:#dee3ea;
  --teal-bg:     #006b7a;

  --font-serif:  'Libre Baskerville', Georgia, serif;
  --font-sans:   'Source Sans 3', 'Helvetica Neue', Arial, sans-serif;

  --max-width:   1200px;
  --header-h:    72px;
  --transition:  0.25s ease;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-sans);
  background: var(--dark-bg);
  color: var(--text-muted);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
address { font-style: normal; }
ul, ol { list-style: none; }

/* ---- Container -------------------------------------------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
}

/* ---- Typography ------------------------------------------- */
h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 400;
  line-height: 1.25;
  color: var(--white);
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.4rem); }
h4 { font-size: 1rem; }

p { line-height: 1.75; }

.text-upper {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.text-teal { color: var(--teal); }
.text-white { color: var(--white); }
/* ============================================================
   MOBILE MENU & DROPDOWN STYLES
   ============================================================ */
/* 让手机菜单最多只占屏幕一半，并支持滑动 */
.mobile-menu {
  max-height: 50vh; /* 50% 视口高度 */
  overflow-y: auto; /* 允许垂直滑动 */
  overscroll-behavior: contain; /* 防止滑动穿透到底部网页 */
}

/* 手机端折叠菜单基础样式 */
.mobile-dropdown {
  display: block;
  width: 100%;
}

.mobile-dropdown-toggle {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05); /* 根据你原有的分隔线调整 */
}

.mobile-dropdown-toggle a {
  flex-grow: 1; /* 文字占据大部分空间，点击文字可以跳转 */
  border-bottom: none !important; /* 移除 a 标签原本自带的边框 */
}

.mobile-dropdown-toggle .toggle-icon {
  padding: 1rem;
  color: rgba(255, 255, 255, 0.7);
  cursor: pointer;
  transition: transform 0.3s ease;
}

/* 折叠展开时的箭头旋转 */
.mobile-dropdown.open .toggle-icon {
  transform: rotate(180deg);
}

/* 子菜单默认隐藏 */
.mobile-dropdown-content {
  display: none; 
  flex-direction: column;
  background-color: rgba(255, 255, 255, 0.03); /* 轻微的背景色区分 */
}

/* 展开子菜单的类名 */
.mobile-dropdown-content.show {
  display: flex; 
}

.mobile-menu .mobile-sub-link {
  padding: 0.75rem 1rem 0.75rem 2rem !important; /* 左侧留出缩进 */
  font-size: 0.9rem !important;
  color: rgba(255, 255, 255, 0.6) !important;
  border-bottom: none !important;
}

.mobile-menu .mobile-sub-link:hover {
  color: #ffffff !important;
}
/* ---- Buttons ---------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.5rem;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-outline-white {
  background: transparent;
  color: var(--white);
  border-color: rgba(255,255,255,0.6);
}
.btn-outline-white:hover {
  background: var(--white);
  color: var(--dark-navy);
  border-color: var(--white);
}

.btn-outline-dark {
  background: transparent;
  color: var(--dark-text);
  border-color: var(--dark-text);
}
.btn-outline-dark:hover {
  background: var(--dark-text);
  color: var(--white);
}

.btn-outline-teal {
  background: transparent;
  color: var(--teal);
  border-color: var(--teal);
}
.btn-outline-teal:hover {
  background: var(--teal);
  color: var(--dark-navy);
}

.btn-group {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

/* ---- Decorative Lines ------------------------------------- */
.deco-line {
  width: 48px;
  height: 2px;
  background: var(--teal);
  margin: 1.25rem 0;
}
.deco-line.center { margin: 1.25rem auto; }
.deco-line.gold   { background: var(--gold-dark); }

/* ---- Section Labels --------------------------------------- */
.section-label {
  display: inline-block;
  font-family: var(--font-sans);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
  background: rgba(0,180,200,0.1);
  padding: 0.3rem 0.75rem;
  margin-bottom: 1rem;
}

/* ---- Section Titles --------------------------------------- */
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  color: var(--white);
  margin-bottom: 0.75rem;
}

.section-desc {
  font-size: 1rem;
  color: var(--text-muted);
  line-height: 1.8;
  max-width: 600px;
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.view-all-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal);
  border-bottom: 1px solid var(--teal);
  padding-bottom: 2px;
  transition: opacity var(--transition);
}
.view-all-link:hover { opacity: 0.7; }

/* ---- Sections --------------------------------------------- */
.section {
  padding: 5rem 0;
}

.section-white  { background: var(--white); }
.section-light  { background: var(--off-white); }
.section-dark   { background: var(--dark-bg); }
.section-darker { background: var(--darker-bg); }
.section-teal   {
  background: var(--teal-bg);
  position: relative;
  overflow: hidden;
}
.section-teal::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0,0,0,0.3) 0%, transparent 60%);
  pointer-events: none;
}

/* ---- Fade-in Animations ----------------------------------- */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: none;
}
.fade-in-delay-1 { transition-delay: 0.15s; }
.fade-in-delay-2 { transition-delay: 0.3s; }
.fade-in-delay-3 { transition-delay: 0.45s; }

/* ============================================================
   HEADER / NAV
   ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10,14,26,0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-dark);
}

.top-bar {
  background: var(--teal-bg);
  padding: 0.35rem 0;
}
.top-bar-inner {
  display: flex;
  justify-content: flex-end;
  gap: 1.5rem;
}
.top-bar a {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.85);
  transition: color var(--transition);
}
.top-bar a:hover { color: var(--white); }

.nav-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: 1rem;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}
.nav-logo img {
  height: 40px;
  width: auto;
  object-fit: contain;
}
.nav-logo-text {
  display: flex;
  flex-direction: column;
  border-left: 1px solid rgba(255,255,255,0.2);
  padding-left: 0.75rem;
}
.nav-logo-text .lab-name {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  color: var(--white);
  line-height: 1.2;
}
.nav-logo-text .lab-sub {
  font-size: 0.65rem;
  color: rgba(255,255,255,0.55);
  letter-spacing: 0.04em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}
.nav-links a {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.7);
  padding: 0.4rem 0.6rem;
  border-bottom: 2px solid transparent;
  transition: all var(--transition);
  white-space: nowrap;
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--white);
  border-bottom-color: var(--teal);
}
.nav-links a.nav-join {
  background: var(--teal);
  color: var(--dark-navy);
  border-color: transparent;
  padding: 0.4rem 1rem;
  margin-left: 0.5rem;
}
.nav-links a.nav-join:hover {
  background: var(--teal-light);
  border-color: transparent;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--white);
  cursor: pointer;
  padding: 0.5rem;
}

.mobile-menu {
  display: none;
  flex-direction: column;
  background: var(--dark-navy);
  border-top: 1px solid var(--border-dark);
  padding: 1rem 2rem;
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
  padding: 0.75rem 0;
  font-size: 0.875rem;
  font-weight: 600;
  color: rgba(255,255,255,0.8);
  border-bottom: 1px solid var(--border-dark);
  transition: color var(--transition);
}
.mobile-menu a:last-child { border-bottom: none; }
.mobile-menu a:hover { color: var(--teal); }
.mobile-menu a.nav-join {
  color: var(--teal);
  font-weight: 700;
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding-top: calc(var(--header-h) + 2rem);
}

/* .hero-bg {
  position: absolute;
  inset: 0;
  background: var(--dark-navy);
  background-image: url('../images/research/details/brain-tumour-scan.jpg');
  background-size: cover;
  background-position: center;
  animation: heroZoom 20s ease-in-out infinite alternate;
} */
@keyframes heroZoom {
  from { transform: scale(1); }
  to   { transform: scale(1.06); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(10,14,26,0.88) 0%,
    rgba(0,107,122,0.55) 50%,
    rgba(10,14,26,0.82) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 800px;
  padding: 2rem;
}
/* .hero-content {
  display: flex;
  flex-direction: column; /* 垂直排列 */

.hero-deco-line {
  width: 60px;
  height: 2px;
  background: rgba(255,255,255,0.5);
  margin: 0 auto 1.5rem;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2.25rem, 6vw, 4.5rem);
  color: var(--white);
  line-height: 1.15;
  margin-bottom: 1.25rem;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: rgba(255,255,255,0.82);
  line-height: 1.75;
  max-width: 600px;
  margin: 0 auto;
}

.hero-scroll {
  position: absolute;
  bottom: 2.5rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
  cursor: pointer;
  animation: bounce 2s ease-in-out infinite;
}
.hero-scroll svg {
  width: 32px;
  height: 32px;
  color: rgba(255,255,255,0.6);
}
@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50%       { transform: translateX(-50%) translateY(8px); }
}

/* ============================================================
   STATS ROW
   ============================================================ */
.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border: 1px solid rgba(255,255,255,0.15);
}

.stat-item {
  padding: 2rem 1.5rem;
  text-align: center;
  border-right: 1px solid rgba(255,255,255,0.15);
}
.stat-item:last-child { border-right: none; }

.stat-item .number {
  font-family: var(--font-serif);
  font-size: 2.75rem;
  color: var(--white);
  line-height: 1;
  margin-bottom: 0.5rem;
}

.stat-item .label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.6);
}

/* ============================================================
   SPOTLIGHT
   ============================================================ */
.spotlight-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  min-height: 420px;
  border: 1px solid var(--border-light);
}

.spotlight-content {
  padding: 3.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.spotlight-image {
  overflow: hidden;
  min-height: 320px;
}

/* ============================================================
   RESEARCH AREAS
   ============================================================ */
.research-areas-list {
  display: flex;
  flex-direction: column;
}

.research-area-item {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border-dark);
  cursor: pointer;
  transition: background var(--transition);
}
.research-area-item:last-child { border-bottom: none; }
.research-area-item:hover { background: rgba(255,255,255,0.03); }
.research-area-item:hover h3 { color: var(--teal); }
.research-area-item:hover .arrow { opacity: 1; transform: translateX(4px); }

.research-area-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--teal);
}

.research-area-item h3 {
  flex: 1;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--white);
  transition: color var(--transition);
}

.research-area-item .arrow {
  color: var(--teal);
  opacity: 0.4;
  transition: all var(--transition);
}

/* ============================================================
   NEWS GRID
   ============================================================ */
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.news-card {
  background: var(--white);
  border: 1px solid var(--border-light);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
}
.news-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.12);
}

.news-card-img {
  width: 100%;
  height: 200px;
  overflow: hidden;
  background: var(--light-gray);
}
.news-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.news-card:hover .news-card-img img { transform: scale(1.05); }

.news-card-badge {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal-dark);
  background: rgba(0,151,167,0.1);
  padding: 0.25rem 0.6rem;
  margin: 1rem 1.25rem 0.5rem;
}

.news-card .date {
  font-size: 0.75rem;
  color: var(--mid-gray);
  margin: 0 1.25rem 0.5rem;
}

.news-card h3 {
  font-family: var(--font-serif);
  font-size: 1rem;
  color: var(--dark-text);
  line-height: 1.45;
  margin: 0 1.25rem 1rem;
}

.news-card .deco-line {
  width: 32px;
  height: 2px;
  background: var(--teal-dark);
  margin: 0 1.25rem 1.25rem;
}

/* Homepage news card without image */
.news-card.news-card-noimg {
  padding-top: 0;
}
.news-card.news-card-noimg .news-card-badge {
  margin-top: 1.5rem;
}

/* News list (news.html) */
.news-list-item {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 2.5rem;
  padding: 2.5rem 0;
  border-bottom: 1px solid var(--border-light);
  align-items: start;
}
.news-list-item:last-child { border-bottom: none; }

.news-list-img {
  width: 280px;
  height: 180px;
  overflow: hidden;
  flex-shrink: 0;
  background: var(--light-gray);
}
.news-list-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.news-list-body .meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

/* ============================================================
   CTA BANNER
   ============================================================ */
.cta-banner {
  background: var(--teal-bg);
  padding: 5rem 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0,0,0,0.3) 0%, transparent 70%);
}
.cta-banner h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  color: var(--white);
  margin-bottom: 1rem;
}
.cta-banner p {
  color: rgba(255,255,255,0.82);
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

/* ============================================================
   CONTACT
   ============================================================ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.contact-card {
  padding: 2rem;
  border: 1px solid var(--border-dark);
  background: rgba(255,255,255,0.03);
}

.contact-card h3 {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 1rem;
}

.contact-card p, .contact-card address {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.8;
}

.contact-card a {
  color: var(--teal);
  transition: color var(--transition);
}
.contact-card a:hover { color: var(--teal-light); }

/* ============================================================
   PAGE HERO (inner pages)
   ============================================================ */
.page-hero {
  background: var(--dark-navy);
  padding: calc(var(--header-h) + 3rem) 0 3.5rem;
  border-bottom: 1px solid var(--border-dark);
}

.page-hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 5vw, 3.5rem);
  color: var(--white);
  margin-bottom: 1rem;
}

.page-hero p {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.7);
  max-width: 600px;
  line-height: 1.75;
}

/* ============================================================
   PEOPLE PAGE
   ============================================================ */

/* Carousel */
.carousel-wrap {
  position: relative;
  width: 100%;
  max-height: 560px;
  overflow: hidden;
}

.carousel-main-img {
  width: 100%;
  height: 560px;
  object-fit: cover;
  display: block;
  transition: opacity 0.4s ease;
}

.carousel-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 1.5rem 2rem;
  background: linear-gradient(to top, rgba(10,14,26,0.9) 0%, transparent 100%);
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
}

.carousel-year {
  font-family: var(--font-serif);
  font-size: 3rem;
  color: rgba(255,255,255,0.9);
  line-height: 1;
}

.carousel-controls {
  display: flex;
  gap: 0.5rem;
}

.carousel-btn {
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.3);
  color: var(--white);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background var(--transition);
}
.carousel-btn:hover { background: rgba(255,255,255,0.3); }

.carousel-thumbs {
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  padding: 1rem 0;
  scrollbar-width: thin;
  scrollbar-color: var(--teal) transparent;
}
.carousel-thumbs::-webkit-scrollbar { height: 4px; }
.carousel-thumbs::-webkit-scrollbar-track { background: transparent; }
.carousel-thumbs::-webkit-scrollbar-thumb { background: var(--teal); border-radius: 2px; }

.carousel-thumb {
  flex-shrink: 0;
  width: 80px;
  height: 56px;
  overflow: hidden;
  border: 2px solid transparent;
  cursor: pointer;
  padding: 0;
  background: none;
  transition: border-color var(--transition);
}
.carousel-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.6);
  transition: filter var(--transition);
}
.carousel-thumb.active {
  border-color: var(--teal);
}
.carousel-thumb.active img,
.carousel-thumb:hover img {
  filter: brightness(1);
}

/* Team list (PI, postdocs) */
.team-list {
  display: flex;
  flex-direction: column;
}

.team-list-item {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border-dark);
  cursor: pointer;
  transition: background var(--transition);
}
.team-list-item:last-child { border-bottom: none; }
.team-list-item:hover { background: rgba(255,255,255,0.02); }

.team-list-photo {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  overflow: hidden;
  flex-shrink: 0;
  background: var(--mid-dark);
  border: 2px solid var(--border-dark);
}
.team-list-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
}

.team-list-info { flex: 1; }
.team-list-info h4 {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.2rem;
}
.team-list-info .role {
  font-size: 0.8rem;
  color: var(--teal);
  font-weight: 600;
}

.team-list-arrow {
  color: var(--teal);
  opacity: 0.4;
  transition: all var(--transition);
}
.team-list-item:hover .team-list-arrow {
  opacity: 1;
  transform: translateX(4px);
}

/* Team grid (PhD students) */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 1.5rem;
}

.team-card {
  text-align: center;
}

.team-card-photo {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  overflow: hidden;
  margin: 0 auto 1rem;
  background: var(--mid-dark);
  border: 2px solid var(--border-dark);
  transition: border-color var(--transition);
}
.team-card:hover .team-card-photo { border-color: var(--teal); }
.team-card-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
}

.team-card h4 {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.25rem;
}
.team-card .role {
  font-size: 0.75rem;
  color: var(--teal);
  font-weight: 600;
}

/* Former members */
.former-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
}

.former-item {
  padding: 1.25rem 1.5rem;
  border: 1px solid var(--border-dark);
  background: rgba(255,255,255,0.02);
  transition: border-color var(--transition);
}
.former-item:hover { border-color: var(--teal); }

.former-item .name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.2rem;
}
.former-item .role {
  font-size: 0.75rem;
  color: var(--teal);
  font-weight: 600;
  margin-bottom: 0.4rem;
}
.former-item .current {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.hidden-member { display: none; }

/* ============================================================
   PUBLICATIONS PAGE
   ============================================================ */
.pub-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--border-dark);
}

.pub-stat {
  padding: 2rem;
  text-align: center;
  border-right: 1px solid var(--border-dark);
}
.pub-stat:last-child { border-right: none; }

.pub-stat .number {
  font-family: var(--font-serif);
  font-size: 2.5rem;
  color: var(--white);
  line-height: 1;
  margin-bottom: 0.5rem;
}
.pub-stat .label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.pub-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border-dark);
  margin-bottom: 2rem;
}

.pub-tab {
  background: none;
  border: none;
  border-bottom: 3px solid transparent;
  padding: 1rem 1.5rem;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.pub-tab:hover { color: var(--white); }
.pub-tab.active {
  color: var(--teal);
  border-bottom-color: var(--teal);
}

.pub-count {
  background: rgba(0,180,200,0.15);
  color: var(--teal);
  font-size: 0.65rem;
  padding: 0.15rem 0.5rem;
  border-radius: 2px;
}

.year-filter {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 2rem;
}
.year-filter label {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.year-filter select {
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-dark);
  color: var(--white);
  padding: 0.4rem 0.75rem;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  cursor: pointer;
  outline: none;
}
.year-filter select:focus { border-color: var(--teal); }
.year-filter select option { background: var(--dark-bg); }

.pub-year-header {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  color: var(--teal);
  margin-bottom: 1.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-dark);
}

.pub-item {
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border-dark);
}
.pub-item:last-child { border-bottom: none; }

.pub-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--white);
  line-height: 1.5;
  margin-bottom: 0.4rem;
}

.pub-authors {
  font-size: 0.825rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
  line-height: 1.5;
}

.pub-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}
.pub-meta span {
  font-size: 0.775rem;
  color: var(--text-muted);
}
.pub-meta .journal {
  font-style: italic;
  color: var(--teal);
  font-weight: 600;
}
.doi-link {
  font-size: 0.75rem;
  color: var(--teal);
  font-weight: 700;
  border-bottom: 1px solid var(--teal);
  transition: opacity var(--transition);
}
.doi-link:hover { opacity: 0.7; }

/* ============================================================
   JOIN US PAGE
   ============================================================ */
.opportunities-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.opportunity-card {
  padding: 2.5rem;
  border: 1px solid var(--border-dark);
  background: rgba(255,255,255,0.03);
  transition: border-color var(--transition), background var(--transition);
}
.opportunity-card:hover {
  border-color: var(--teal);
  background: rgba(0,180,200,0.04);
}

.opportunity-icon {
  color: var(--teal);
  margin-bottom: 1.25rem;
}

.opportunity-card h3 {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  color: var(--white);
  margin-bottom: 1rem;
}

.opportunity-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.8;
}

/* ============================================================
   ACKNOWLEDGEMENTS PAGE
   ============================================================ */
.funding-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 1.5rem;
}

.funding-item {
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-dark);
  padding: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100px;
  transition: border-color var(--transition);
}
.funding-item:hover { border-color: var(--teal); }
.funding-item img {
  max-height: 60px;
  width: auto;
  filter: brightness(0) invert(1);
  opacity: 0.7;
  transition: opacity var(--transition);
}
.funding-item:hover img { opacity: 1; }

/* ============================================================
   RESEARCH DETAIL PAGES
   ============================================================ */
.research-detail-content h2 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  color: var(--white);
  margin: 2.5rem 0 1rem;
}
.research-detail-content h2:first-child { margin-top: 0; }

.research-detail-content p {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.85;
  margin-bottom: 1.25rem;
}

.research-detail-content img {
  width: 100%;
  height: auto;
  margin: 1.5rem 0 0.5rem;
  border: 1px solid var(--border-dark);
}

.research-detail-content .img-caption {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
  font-style: italic;
  margin-bottom: 2rem;
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: var(--dark-navy);
  border-top: 1px solid var(--border-dark);
  padding: 3rem 0 2rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.5rem;
  justify-content: center;
  margin-bottom: 1.5rem;
}
.footer-links a {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  transition: color var(--transition);
}
.footer-links a:hover { color: var(--teal); }

.footer-social {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}
.footer-social a {
  width: 36px;
  height: 36px;
  border: 1px solid rgba(255,255,255,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.5);
  transition: all var(--transition);
}
.footer-social a:hover {
  border-color: var(--teal);
  color: var(--teal);
}

.footer-info {
  text-align: center;
  border-top: 1px solid var(--border-dark);
  padding-top: 1.5rem;
}
.footer-info p {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
  line-height: 1.7;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1100px) {
  .nav-links a {
    font-size: 0.65rem;
    padding: 0.4rem 0.45rem;
  }
}

@media (max-width: 900px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: flex; }

  .stats-row { grid-template-columns: repeat(2, 1fr); }
  .stat-item:nth-child(2) { border-right: none; }
  .stat-item:nth-child(3) { border-top: 1px solid rgba(255,255,255,0.15); }
  .stat-item:nth-child(4) { border-top: 1px solid rgba(255,255,255,0.15); }

  .spotlight-section { grid-template-columns: 1fr; }
  .spotlight-image { min-height: 240px; }

  .news-grid { grid-template-columns: repeat(2, 1fr); }

  .contact-grid { grid-template-columns: 1fr; }

  .pub-stats { grid-template-columns: 1fr; }
  .pub-stat { border-right: none; border-bottom: 1px solid var(--border-dark); }
  .pub-stat:last-child { border-bottom: none; }

  .opportunities-grid { grid-template-columns: 1fr; }

  .join-grid { grid-template-columns: 1fr !important; }

  .news-list-item { grid-template-columns: 1fr; }
  .news-list-img { width: 100%; }
}

@media (max-width: 640px) {
  .container { padding: 0 1.25rem; }
  .section { padding: 3.5rem 0; }

  .hero-title { font-size: 2rem; }
  .stats-row { grid-template-columns: 1fr 1fr; }

  .news-grid { grid-template-columns: 1fr; }

  .team-grid { grid-template-columns: repeat(2, 1fr); }

  .former-grid { grid-template-columns: 1fr; }

  .pub-tabs { flex-wrap: wrap; }
  .pub-tab { font-size: 0.7rem; padding: 0.75rem 1rem; }

  .section-header { flex-direction: column; align-items: flex-start; }

  .nav-logo-text .lab-sub { display: none; }

  .carousel-main-img { height: 280px; }
  .carousel-year { font-size: 2rem; }

  .btn-group { flex-direction: column; align-items: center; }
}

/* ============================================================
   PI FEATURE SECTION (homepage)
   ============================================================ */
.pi-feature {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: 520px;
}

.pi-feature-img {
  position: relative;
  overflow: hidden;
}
.pi-feature-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  filter: brightness(0.8);
  transition: transform 0.6s ease;
}
.pi-feature:hover .pi-feature-img img { transform: scale(1.04); }
.pi-feature-img-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to right, transparent 55%, var(--dark-bg) 100%);
}

.pi-feature-content {
  padding: 4rem 3.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--dark-bg);
}

@media (max-width: 900px) {
  .pi-feature {
    grid-template-columns: 1fr;
  }
  .pi-feature-img {
    height: 300px;
  }
  .pi-feature-img-overlay {
    background: linear-gradient(to top, var(--dark-bg) 0%, transparent 60%);
  }
  .pi-feature-content {
    padding: 2.5rem 2rem;
  }
}

/* ============================================================
   PROFILE PLACEHOLDER ANIMATION
   ============================================================ */
.profile-placeholder {
  position: relative;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #0d1120 0%, #141929 50%, #0d1120 100%);
  background-size: 200% 200%;
  animation: shimmer 3s ease-in-out infinite;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

@keyframes shimmer {
  0%   { background-position: 0% 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.profile-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(0,180,200,0.06) 50%,
    transparent 100%
  );
  background-size: 200% 100%;
  animation: shimmer-sweep 2.5s ease-in-out infinite;
}

@keyframes shimmer-sweep {
  0%   { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.profile-placeholder-icon {
  width: 48px;
  height: 48px;
  color: rgba(0,180,200,0.3);
  z-index: 1;
}

/* Circular placeholder for team cards */
.team-card-photo .profile-placeholder,
.team-list-photo .profile-placeholder {
  border-radius: 50%;
}

/* ============================================================
   RESEARCH GRID (homepage two-column)
   ============================================================ */
.research-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.research-col-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
  border-bottom: 1px solid var(--border-dark);
  padding-bottom: 0.75rem;
  margin-bottom: 0.5rem;
}

@media (max-width: 640px) {
  .research-cols { grid-template-columns: 1fr; }
}

/* ============================================================
   SPOTLIGHT (homepage) — light background variant
   ============================================================ */
.spotlight-section .spotlight-content {
  background: var(--off-white);
}
.spotlight-section .spotlight-content h2 { color: var(--dark-text); }
.spotlight-section .spotlight-content .section-label { color: var(--teal-dark); background: rgba(0,151,167,0.1); }
.spotlight-section .spotlight-content p { color: #4a5568; }
.spotlight-section .spotlight-content .deco-line { background: var(--teal-dark); }

/* ============================================================
   PEOPLE PAGE — PI full-width hero
   ============================================================ */
.pi-hero {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 0;
  background: var(--dark-bg);
  border: 1px solid var(--border-dark);
  margin-bottom: 3rem;
}

.pi-hero-photo {
  height: 420px;
  overflow: hidden;
}
.pi-hero-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
}

.pi-hero-content {
  padding: 3rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.pi-hero-name {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  color: var(--white);
  margin-bottom: 0.25rem;
}

.pi-hero-title {
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--teal);
  margin-bottom: 1.25rem;
}

.pi-hero-bio {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.85;
  margin-bottom: 1.5rem;
}

.pi-hero-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

@media (max-width: 900px) {
  .pi-hero { grid-template-columns: 1fr; }
  .pi-hero-photo { height: 280px; }
  .pi-hero-content { padding: 2rem; }
}

/* ============================================================
   ACKNOWLEDGEMENTS PAGE
   ============================================================ */
.ack-section-title {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
  border-bottom: 1px solid var(--border-dark);
  padding-bottom: 0.75rem;
  margin-bottom: 1.5rem;
}

/* ============================================================
   RESEARCH PAGE HERO IMAGE
   ============================================================ */
.research-hero-img {
  width: 100%;
  height: 380px;
  overflow: hidden;
  position: relative;
}
.research-hero-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}
.research-hero-img::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent 50%, var(--dark-bg) 100%);
}

/* ============================================================
   HERO VIDEO BACKGROUND
   ============================================================ */
.hero .hero-bg video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.4);
}

/* ============================================================
   SCROLLBAR
   ============================================================ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--dark-bg); }
::-webkit-scrollbar-thumb { background: var(--teal-bg); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--teal); }

/* ============================================================
   SELECTION
   ============================================================ */
::selection {
  background: rgba(0,180,200,0.25);
  color: var(--white);
}

/* ============================================================
   RESEARCH DETAIL — SIDEBAR & LAYOUT
   ============================================================ */
.research-detail-layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 3rem;
  align-items: start;
}

.research-sidebar {
  position: sticky;
  top: calc(var(--header-h) + 2rem);
}

.research-sidebar-label {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-dark);
}

.research-sidebar a {
  display: block;
  font-size: 0.82rem;
  color: var(--text-muted);
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-dark);
  transition: color var(--transition), padding-left var(--transition);
}
.research-sidebar a:hover,
.research-sidebar a.active {
  color: var(--teal);
  padding-left: 0.5rem;
}
.research-sidebar a:last-of-type { border-bottom: none; }

@media (max-width: 768px) {
  .research-detail-layout {
    grid-template-columns: 1fr;
  }
  .research-sidebar {
    position: static;
    border: 1px solid var(--border-dark);
    padding: 1.25rem;
    background: rgba(255,255,255,0.02);
  }
}

/* ============================================================
   NEWS LIST PAGE — improved item layout
   ============================================================ */
.news-list-body h3 {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  color: var(--dark-text);
  line-height: 1.5;
  margin-bottom: 0.75rem;
}

.news-list-body p {
  font-size: 0.9rem;
  color: #4a5568;
  line-height: 1.75;
}

.news-list-body .meta-badge {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal-dark);
  background: rgba(0,151,167,0.1);
  padding: 0.2rem 0.6rem;
}

.news-list-body .meta-date {
  font-size: 0.78rem;
  color: var(--mid-gray);
}

/* ============================================================
   FUNDING CARDS GRID
   ============================================================ */
.funding-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.funding-card {
  padding: 2rem;
  border: 1px solid var(--border-dark);
  background: rgba(255,255,255,0.02);
  transition: border-color var(--transition), background var(--transition);
}
.funding-card:hover {
  border-color: var(--teal);
  background: rgba(0,180,200,0.03);
}

.funding-card h3 {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.5rem;
}

.funding-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ============================================================
   COLLABORATORS GRID
   ============================================================ */
.collaborators-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.collaborator-item {
  padding: 1.5rem;
  border: 1px solid var(--border-dark);
  background: rgba(255,255,255,0.02);
  text-align: center;
  transition: border-color var(--transition);
}
.collaborator-item:hover { border-color: var(--teal); }

.collaborator-item h4 {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 0.35rem;
}

.collaborator-item p {
  font-size: 0.78rem;
  color: var(--text-muted);
}
/* ============================================================
   NAVIGATION DROPDOWN STYLES
   ============================================================ */

/* Container for the dropdown */
.nav-dropdown {
  position: relative;
  display: inline-block;
  height: 100%; /* Ensures hover area covers the full height of the nav bar */
}

/* The hidden dropdown menu */
.nav-dropdown .dropdown-content {
  visibility: hidden;
  opacity: 0;
  position: absolute;
  top: 100%;
  left: 0;
  background-color: #11151c; /* Matches your dark navy nav background */
  min-width: 240px;
  box-shadow: 0px 10px 25px rgba(0, 0, 0, 0.5);
  z-index: 9999;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s;
  border-radius: 4px;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-top: 3px solid #00acc1; /* Teal accent to match your active states */
  padding: 0.5rem 0;
}

/* Show the dropdown on hover */
.nav-dropdown:hover .dropdown-content {
  visibility: visible;
  opacity: 1;
  transform: translateY(0);
}

/* Styling the links inside the dropdown */
.nav-dropdown .dropdown-content a {
  color: rgba(255, 255, 255, 0.7) !important;
  padding: 0.75rem 1.25rem !important;
  display: block;
  font-size: 0.85rem !important;
  text-transform: none !important; /* Prevents ALL CAPS for sub-menus */
  font-weight: 500 !important;
  letter-spacing: 0.5px !important;
  transition: background-color 0.2s, color 0.2s;
  margin: 0 !important;
}

/* Hover effect for dropdown links */
.nav-dropdown .dropdown-content a:hover {
  background-color: rgba(255, 255, 255, 0.05);
  color: #ffffff !important;
}

/* Keep the main "RESEARCH" link styled properly when the dropdown is open */
.nav-dropdown:hover > a {
  color: #ffffff;
}

/* Rotate the arrow slightly on hover */
.nav-dropdown:hover > a svg {
  transform: rotate(180deg);
  transition: transform 0.3s ease;
}

.nav-dropdown > a svg {
  transition: transform 0.3s ease;
}

/* Mobile sub-link styling */
.mobile-menu .mobile-sub-link {
  padding-left: 2rem !important;
  font-size: 0.95rem !important;
  color: rgba(255, 255, 255, 0.6) !important;
}

.mobile-menu .mobile-sub-link:hover {
  color: #ffffff !important;
}
/* ============================================================
   PAGE HERO — with background image variant
   ============================================================ */
.page-hero-img {
  background-size: cover;
  background-position: center;
  position: relative;
}
.page-hero-img::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(10,14,26,0.78);
}
.page-hero-img .container { position: relative; z-index: 1; }

/* ── People page: group photo hero banner ── */
.people-hero {
  position: relative;
  min-height: 480px;
  display: flex;
  align-items: flex-end;
  padding: calc(var(--header-h) + 2rem) 0 4rem;
  overflow: hidden;
  background: var(--dark-bg);
}
.people-hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center 30%;
  background-repeat: no-repeat;
  transform: scale(1.04);
  transition: transform 8s ease;
}
.people-hero:hover .people-hero-bg { transform: scale(1.0); }
.people-hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to bottom,
    rgba(10,14,26,0.45) 0%,
    rgba(10,14,26,0.72) 60%,
    rgba(10,14,26,0.92) 100%
  );
}
.people-hero-content {
  position: relative;
  z-index: 2;
}
.people-hero h1 { color: #fff; }
.people-hero p  { color: rgba(255,255,255,0.82); }
/* 假设你的 main.js 会在点击时给 body 或 nav 添加 open/active 类 
   以下是强行防止 SVG 图标重叠的通用防御性 CSS */
.mobile-menu-btn svg {
  transition: transform 0.3s ease;
}
/* 如果你的 JS 是在按钮里额外插入了一个 SVG，隐藏多余的 */
.mobile-menu-btn svg:nth-child(2) {
  display: none !important; 
}
/* ============================================================
   PRINT STYLES
   ============================================================ */
@media print {
  .site-header, .hero-scroll, .mobile-menu-btn, .mobile-menu,
  .cta-banner, .site-footer { display: none !important; }
  body { background: white; color: black; }
  .section { padding: 2rem 0; }
}
/* 确保父容器是 Flex 布局以实现左右等高 */
.spotlight-section {
  display: flex;
  align-items: stretch; /* 左右等高 */
  flex-wrap: wrap;
  gap: 2rem;
}



/* /* =========================================
   桌面端/全局基础样式
   ========================================= */
.spotlight-section {
  display: flex;
  align-items: center; /* 垂直居中对齐 */
  justify-content: space-between;
  gap: 3rem; /* 桌面端图文间距 */
}

.spotlight-content {
  flex: 1; /* 让文字部分占据可用空间 */
}
/* 基础样式：确保视频铺满背景 */
.hero-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;

}

/* 默认隐藏手机端视频（电脑端优先显示） */
.mobile-video {
  display: none;
}

/* 当屏幕宽度小于 768px 时 */
@media (max-width: 767px) {
  .desktop-video {
    display: none; /* 隐藏电脑视频 */
  }
  .mobile-video {
    display: block; /* 显示手机视频 */
  }
}
.spotlight-image {
  flex: 1; /* 让图片容器占据等量空间 */
  flex-shrink: 0; /* 关键：防止在空间不足时图片容器被强行挤压 */
  max-width: 50%; /* 限制图片最大宽度，避免过大 */
}

.spotlight-image img {
  width: 100%;
  height: auto; /* 关键：让高度根据宽度自动按比例缩放，防止变形 */
  display: block;
  border-radius: 8px; /* 可选：增加一点圆角让视觉更柔和 */
  /* 如果你的图片容器有固定高度，才需要用 object-fit。
     既然用了 height: auto，object-fit 其实可以省略，但保留也无妨 */
  object-fit: cover; 
}

/* =========================================
   移动端/小屏幕响应式调整 (手机和平板)
   ========================================= */
@media (max-width: 768px) {
  .spotlight-section {
    flex-direction: column; /* 核心修复：将左右排列改为上下堆叠 */
    gap: 2rem; /* 减小手机端的图文间距 */
  }

  .spotlight-content,
  .spotlight-image {
    width: 100%; /* 确保图文容器都占满屏幕宽度 */
    max-width: 100%; /* 覆盖桌面端的 max-width */
  }

  .spotlight-image img {
    width: 100%;
    height: auto; /* 再次确认高度自适应，保持图片原始比例 */
    object-fit: contain; /* 确保整图展示，不被裁剪 */
    margin: 0 auto;
  } 
}  
  /* 可选：手机端让文字居中对齐，视觉更平衡 */
  /*
  .spotlight-content {
    text-align: center;
  }
  .spotlight-content .deco-line {
    margin-left: auto;
    margin-right: auto;
  }
 
  */

/* ============================================================
   SPOTLIGHT CAROUSEL & CARDS
   ============================================================ */

/* 1. 滑动轮播容器 */
.spotlight-carousel {
  display: flex;
  gap: 2rem; /* 卡片之间的间距 */
  overflow-x: auto; /* 允许横向滚动 */
  padding: 1rem 0 3rem 0; /* 上下留白，确保底部阴影不被裁剪 */
  
  /* CSS 滚动吸附魔法：让滑动像原生 App 一样一段一段停住 */
  scroll-snap-type: x mandatory; 
  -webkit-overflow-scrolling: touch; /* 确保 iOS 上滑动顺滑 */
  
  /* 隐藏默认丑陋的滚动条 (现代浏览器适用) */
  scrollbar-width: none; 
}
.spotlight-carousel::-webkit-scrollbar {
  display: none; /* Chrome/Safari 隐藏滚动条 */
}

/* 2. 单个浮空卡片 */
.spotlight-card {
  flex: 0 0 100%; /* 默认状态下每个卡片占满父容器宽度 */
  display: flex;
  background: var(--off-white, #ffffff);
  border-radius: 16px; /* 卡片圆角 */
  overflow: hidden; /* 保证内部图文不出圆角 */
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08); /* 核心：浮空阴影效果 */
  border: 1px solid var(--border-light, #eaeaea);
  scroll-snap-align: center; /* 滚动停止时，卡片自动居中对齐 */
}

/* 3. 卡片内部排版 (桌面端) */
.spotlight-content {
  flex: 1; /* 文字占 50% */
  padding: 3.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--off-white, #ffffff);
}

.spotlight-image {
  flex: 1; /* 图片占 50% */
  min-height: 320px;
  position: relative; /* 为 object-fit 铺垫 */
}

.spotlight-image img {
  width: 100%;
  height: 100%;
  object-fit: contain; /* 保证图片充满区域且不变形 */
  display: block;
}

/* =========================================
   移动端/小屏幕响应式调整 (手机和平板)
   ========================================= */
@media (max-width: 850px) {
  .spotlight-card {
    flex-direction: column; /* 手机端上下堆叠 */
    /* 核心交互技巧：设置为 90% 宽度，边缘会微微露出下一张卡片，
       这在视觉上强烈暗示用户“这里可以左右滑动” */
    flex: 0 0 90%; 
  }

  .spotlight-content {
    padding: 2rem; /* 手机端减小内边距 */
  }

  .spotlight-image {
    min-height: 250px;
    /* 在上下堆叠模式下，如果你希望图片显示完整而不是被裁剪，可以改用 contain */
    /* object-fit: contain; 
       background-color: #f8f9fa; */
  }
}
/* ============================================================
   桌面端左右切换箭头
   ============================================================ */
/* ============================================================
   SPOTLIGHT CAROUSEL & CARDS (最终整合版)
   ============================================================ */

/* 1. 滑动轮播容器 */
.spotlight-carousel {
  display: flex;
  flex-wrap: nowrap !important; /* 核心修复：强制绝对不换行 */
  gap: 2rem;
  overflow-x: auto;
  padding: 1rem 0 3rem 0; /* 给卡片底部阴影留出空间 */
  scroll-snap-type: x mandatory; 
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth; /* 配合JS实现平滑滚动 */
  
  /* 如果你想隐藏滚动条，取消下面两行的注释： */
  /* scrollbar-width: none; */
}
/* .spotlight-carousel::-webkit-scrollbar { display: none; } */

/* 2. 单个浮空卡片 */
.spotlight-card {
  flex: 0 0 100%;
  min-width: 100%; /* 核心修复：双重保险防止被挤压 */
  display: flex;
  background: var(--off-white, #ffffff);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08); /* 浮空阴影 */
  border: 1px solid var(--border-light, #eaeaea);
  scroll-snap-align: center;
}

/* 3. 卡片内部排版 (桌面端) */
.spotlight-content {
  flex: 1;
  padding: 3.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--off-white, #ffffff);
}

.spotlight-image {
  flex: 1;
  min-height: 320px;
  position: relative;
}

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

/* 4. 桌面端左右切换箭头 */
.carousel-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: #ffffff;
  border: 1px solid var(--border-light, #eaeaea);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--dark-text, #1a1a2e);
  transition: all 0.3s ease;
}

.carousel-nav svg {
  width: 24px;
  height: 24px;
}

.carousel-nav:hover {
  background-color: var(--off-white, #f8f9fa);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.15);
  transform: translateY(-50%) scale(1.05); /* 鼠标悬停微微放大 */
}
/* 箭头隐藏时的状态 (加入平滑过渡效果) */
.carousel-nav.is-hidden {
  opacity: 0;
  pointer-events: none; /* 关键：变成透明后，鼠标也无法点击到它 */
  transform: translateY(-50%) scale(0.8); /* 微微缩小淡出，比生硬消失更好看 */
}
.carousel-nav.prev {
  left: -24px; /* 移到左侧外 */
}

.carousel-nav.next {
  right: -24px; /* 移到右侧外 */
}

/* =========================================
   移动端/小屏幕响应式调整
   ========================================= */
/* =========================================
   移动端/小屏幕响应式高级优化 (手机和平板)
   ========================================= */
@media (max-width: 850px) {
  .spotlight-carousel {
    /* 1. 缩小卡片之间的间隙，让手机端布局更紧凑 */
    gap: 1rem;
    padding-bottom: 2rem; /* 给底部的自定义滚动条留出一点空间 */
    
    /* 2. 核心交互修复：重新显示滚动条，并把它变成现代感极细进度条 */
    scrollbar-width: thin; /* Firefox 支持 */
    scrollbar-color: rgba(0, 151, 167, 0.5) transparent; /* 使用你的主题色 */
  }

  /* 针对 Webkit 浏览器 (Safari, iPhone, Chrome) 的高级滚动条美化 */
  .spotlight-carousel::-webkit-scrollbar {
    display: block; /* 覆盖之前隐藏的代码 */
    height: 3px; /* 极其纤细，毫不抢戏 */
  }
  .spotlight-carousel::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.04); /* 极淡的轨道背景 */
    border-radius: 10px;
    margin: 0 2rem; /* 让滚动条两边留点白，不顶到屏幕边缘 */
  }
  .spotlight-carousel::-webkit-scrollbar-thumb {
    background: var(--teal-dark, #0097a7); /* 你的主题色（青色） */
    border-radius: 10px;
  }

  .spotlight-card {
    flex-direction: column;
    /* 3. 宽度设为 88%，右侧刚好优雅地露出下一张卡片的阴影和边缘 */
    flex: 0 0 88%; 
    min-width: 88%; 
    /* 4. 核心排版修复：改为 start（左对齐），解决第一张卡片左侧出现奇怪空白的问题 */
    scroll-snap-align: start; 
  }

  .spotlight-content {
    padding: 2rem; /* 减小内边距，让文字在小屏幕更好阅读 */
  }

  .spotlight-image {
    min-height: 250px;
  }

  .carousel-nav {
    display: none; /* 手机端依然隐藏两侧的大箭头 */
  }
}
/* 按钮组容器 */
.btn-group {
  display: flex;
  gap: 1rem; /* 按钮之间的间距 */
  flex-wrap: wrap; /* 手机端自动换行 */
}

/* 统一样式 */
.btn-group .btn {
  padding: 0.8rem 1.5rem;
  font-size: 0.85rem;
  letter-spacing: 1px;
  text-decoration: none;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 8px; /* 图标与文字间距 */
}

/* 媒体报道专用按钮样式 */
.btn-media {
  background: transparent;
  color: var(--gold-dark, #d4a017);
  border: 1px solid var(--gold-dark, #d4a017);
}

.btn-media:hover {
  background: rgba(212, 160, 23, 0.05);
  box-shadow: 0 4px 12px rgba(212, 160, 23, 0.15);
  transform: translateY(-2px);
}

/* 移动端微调 */
@media (max-width: 480px) {
  .btn-group {
    flex-direction: column; /* 屏幕太小时上下堆叠 */
  }
}
/* =========================================
   Spotlight 专属按钮组：强制对称排版
   ========================================= */
/* =========================================
   Spotlight 专属按钮组：强制固定大小，完美对齐
   ========================================= */
/* =========================================
   Spotlight 专属按钮组：强制固定大小，完美对齐 (防拥挤版)
   ========================================= */
/* =========================================
   Spotlight 专属按钮组：使用 Grid 强制等宽 (终极版)
   ========================================= */
/* =========================================
   Spotlight 专属按钮组：强制等宽 (破除内容撑大限制版)
   ========================================= */
.spotlight-btn-group {
  display: flex;
  flex-direction: column; /* 🌟 关键：让按钮上下纵向排列 */
  gap: 1rem; /* 控制两个按钮之间的上下间距，觉得近了就调大 */
  width: 100%;
  max-width: 280px; /* 建议把最大宽度调小一点（比如 280px 或 300px），不然电脑上按钮会拉得太长 */
}

.spotlight-btn-group .btn {
  width: 100%;
  display: flex; 
  align-items: center;
  justify-content: center; 
  text-align: center;
  padding: 0.8rem 1rem;
  box-sizing: border-box;
  white-space: nowrap; 
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 移动端适配 */
@media (max-width: 480px) {
  .spotlight-btn-group {
    grid-template-columns: 1fr; /* 手机端恢复成一列 */
    gap: 1。5rem;
  }
}
/* =========================================
   针对 PNAS 复杂图表卡片的特殊悬停放大效果
   ========================================= */
#pnas-connectivity-card {
  /* 为放大效果增加平滑的过渡动画 */
  transition: transform 0.4s ease, z-index 0s, box-shadow 0.4s ease !important;
  /* 确保初始状态有 z-index 基础 */
  z-index: 1; 
}

/* 当鼠标悬停在这一张卡片上时 */
#pnas-connectivity-card:hover {
  /* 1. 🌟 核心：z-index 设为极大，确保它浮在最上层，不被两边的卡片遮挡 */
  z-index: 100 !important;
  
  /* 2. 🌟 核心：整体放大 1.5 倍（根据需要调整），并强制取消 3D 轮播带来的旋转角度，使其正对用户 */
  transform: translateZ(100px) scale(1.5) rotateY(0deg) !important;
  
  /* 3. 增加更深的阴影，强化浮起感 */
  box-shadow: 0 20px 50px rgba(0,0,0,0.3) !important;
}

/* 悬停时稍微调低文字蒙版的透明度，更突出图片，或者你也可以选择直接隐藏文字 */
#pnas-connectivity-card:hover .carousel-3d-overlay {
  background: rgba(0, 0, 0, 0.6); /* 稍微变透明一点点 */
  /* 如果你想悬停时彻底隐藏文字专注于看图，用下面这行： */
  /* opacity: 0; */
}