/* ==========================================================================
   AxiomWorks Web - Academic & Research Portfolio
   Style System for 徐子涵 (Xu Zihan) - SJTU SMSE Ph.D.
   ========================================================================== */

:root {
  --primary: #1F4E8C;         /* 交大深海蓝 SJTU Deep Blue */
  --primary-dark: #153866;    /* 悬浮深蓝 */
  --primary-light: #EBF2FA;   /* 浅蓝高光底衬 */
  --primary-border: #BCD0E8;  /* 边框高亮 */
  --ink: #1B2636;             /* 正文字体深色 */
  --ink-light: #33445C;       /* 次要正文 */
  --muted: #607289;           /* 辅助说明灰 */
  --line: #D9E2ED;            /* 浅灰分割线 */
  --surface: #FFFFFF;         /* 纯白卡片背景 */
  --ground: #F5F7FB;          /* 页面底灰背景 */
  --accent: #C87B00;          /* 荣誉与专利金标 Accent Gold */
  --accent-light: #FEF7EA;
  --accent-border: #F6D8A8;
  --success: #1E8E5A;
  
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --serif: "Songti SC", "STSong", "SimSun", "Noto Serif SC", serif;
  --mono: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  --shadow-sm: 0 1px 3px rgba(18, 38, 63, 0.05);
  --shadow-md: 0 4px 14px rgba(18, 38, 63, 0.07);
  --shadow-lg: 0 10px 30px rgba(18, 38, 63, 0.12);
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;
}

/* Reset & Box Sizing */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 64px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background-color: var(--ground);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Bilingual Controller */
html.en .zh { display: none !important; }
html:not(.en) .en { display: none !important; }

/* Layout Wrap */
.wrap {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 20px;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* --------------------------------------------------------------------------
   Navigation Bar (Sticky)
   -------------------------------------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(31, 78, 140, 0.96);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  color: #FFFFFF;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.nav .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 54px;
}

.nav-left-group {
  display: flex;
  align-items: center;
}

.menu-toggle {
  display: none;
}

.nav .brand {
  font-weight: 700;
  font-size: 16px;
  color: #FFFFFF;
  letter-spacing: 0.04em;
  display: flex;
  align-items: baseline;
  text-decoration: none;
}

.nav .brand small {
  font-weight: 400;
  font-size: 12px;
  opacity: 0.85;
  margin-left: 8px;
  letter-spacing: 0.08em;
}

.nav .nav-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav .links {
  display: flex;
  gap: 20px;
  font-size: 13.5px;
}

.nav .links a {
  color: rgba(255, 255, 255, 0.88);
  text-decoration: none;
  padding: 4px 0;
  transition: opacity 0.2s ease, border-color 0.2s ease;
  border-bottom: 2px solid transparent;
}

.nav .links a:hover {
  color: #FFFFFF;
  border-bottom-color: rgba(255, 255, 255, 0.8);
}

.lang-btn {
  border: 1px solid rgba(255, 255, 255, 0.65);
  color: #FFFFFF;
  background: transparent;
  border-radius: var(--radius-sm);
  padding: 3px 10px;
  font-size: 12px;
  cursor: pointer;
  letter-spacing: 0.05em;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.lang-btn:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: #FFFFFF;
}

/* --------------------------------------------------------------------------
   Section Common Headers
   -------------------------------------------------------------------------- */
section {
  padding: 46px 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 64px;
}

section:last-of-type {
  border-bottom: none;
}

.sec-tag {
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--muted);
  text-transform: uppercase;
  margin: 0 0 4px 0;
}

.sec-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
  margin: 0 0 6px 0;
  line-height: 1.35;
}

.sec-rule {
  width: 36px;
  height: 3px;
  background: var(--primary);
  border-radius: 2px;
  margin: 0 0 22px 0;
}

.sec-sub {
  color: var(--muted);
  font-size: 14px;
  margin: -10px 0 22px 0;
  line-height: 1.65;
  max-width: 100%;
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
  padding: 44px 0 36px 0;
  background: linear-gradient(180deg, #FFFFFF 0%, var(--ground) 100%);
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 210px;
  gap: 36px;
  align-items: center;
}

.mobile-photo {
  display: none;
}

.desktop-photo {
  display: block;
}

.hero-name-row {
  display: flex;
  align-items: baseline;
  gap: 25px;
  margin: 0 0 6px 0;
}

.hero-name {
  font-family: var(--serif);
  font-size: 40px;
  font-weight: 700;
  line-height: 1.15;
  margin: 0;
  color: var(--ink);
}

.hero-degree {
  font-family: var(--sans);
  font-size: 24px;
  font-weight: 600;
  color: var(--primary);
  line-height: 1.15;
  letter-spacing: 0.05em;
}

.hero-dept-val {
  color: var(--ink);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  margin: 6px 0 10px 0;
}

.hero-contacts {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  margin: 0 0 14px 0;
}

.hero-c-item {
  display: inline-flex;
  align-items: baseline;
  font-size: 13.5px;
  color: var(--ink);
  text-decoration: none;
  transition: color 0.15s ease;
}

.hero-c-item:hover {
  color: var(--primary);
  text-decoration: none;
}

.hero-c-item .c-lbl {
  color: var(--muted);
  font-weight: 500;
  margin-right: 2px;
}

.hero-c-item .c-val {
  color: var(--ink);
  font-weight: 500;
  transition: color 0.15s ease;
}

.hero-c-item:hover .c-val {
  color: var(--primary);
}

.hero-title {
  margin: 14px 0 10px 0;
  font-size: 16.5px;
  font-weight: 600;
  color: var(--primary);
}

.hero-bio {
  color: var(--ink-light);
  font-size: 14.5px;
  line-height: 1.75;
  margin: 0;
  text-align: justify;
}

.hero-photo-wrap {
  width: 200px;
  height: 250px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  background: #FFFFFF;
}

.hero-photo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

/* --------------------------------------------------------------------------
   Proof High-Impact Tiles (关键指标横幅)
   -------------------------------------------------------------------------- */
.proof-banner {
  background: var(--primary-light);
  border-bottom: 1px solid var(--line);
}

.proof-banner .wrap {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  padding: 0;
}

.proof-tile {
  padding: 18px 16px 16px 16px;
  border-right: 1px solid var(--line);
  min-height: 94px;
  transition: background 0.25s ease;
}

.proof-tile:last-child {
  border-right: none;
}

.proof-tile:hover {
  background: #E1ECF7;
}

.proof-tile .num {
  display: block;
  font-size: 16px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.3;
}

.proof-tile .num em {
  font-style: normal;
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
  margin-left: 4px;
}

.proof-tile .desc {
  display: block;
  font-size: 12px;
  color: var(--muted);
  margin-top: 4px;
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Cards Grid System
   -------------------------------------------------------------------------- */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.cards-grid.single {
  grid-template-columns: 1fr;
}

.cards-grid.three {
  grid-template-columns: repeat(3, 1fr);
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  border-color: var(--primary-border);
  box-shadow: var(--shadow-md);
}

.card-badge {
  display: inline-block;
  align-self: flex-start;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-sm);
  padding: 2px 8px;
  font-size: 11.5px;
  font-weight: 600;
  margin-bottom: 8px;
}

.card-badge.gold {
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid var(--accent-border);
}

.card h3 {
  font-size: 16.5px;
  font-weight: 600;
  margin: 0 0 8px 0;
  line-height: 1.4;
  color: var(--ink);
}

.card p {
  margin: 0 0 10px 0;
  font-size: 13.5px;
  color: var(--ink-light);
  line-height: 1.65;
}

.card .tech-points {
  margin: 8px 0 12px 0;
  padding-left: 18px;
  font-size: 13px;
  color: var(--ink-light);
}

.card .tech-points li {
  margin-bottom: 4px;
}

.card .card-footer {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card .tag-pill {
  font-size: 12px;
  color: var(--primary);
  font-weight: 600;
}

.btn-detail {
  background: transparent;
  border: 1px solid var(--primary-border);
  color: var(--primary);
  font-size: 12px;
  font-weight: 500;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-detail:hover {
  background: var(--primary);
  color: #FFFFFF;
  border-color: var(--primary);
}

/* --------------------------------------------------------------------------
   Video Showcase Section
   -------------------------------------------------------------------------- */
.video-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

.video-grid .video-box {
  margin-bottom: 0;
}

.video-box {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 16px;
  box-shadow: var(--shadow-sm);
}

.video-container {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #0F172A;
  border-radius: var(--radius-sm);
  overflow: hidden;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.video-container video {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.video-placeholder {
  text-align: center;
  color: #94A3B8;
  padding: 20px;
}

.video-placeholder .icon-play {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: rgba(31, 78, 140, 0.85);
  color: #FFFFFF;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  font-size: 24px;
}

.video-info {
  margin-top: 12px;
}

.video-info h4 {
  margin: 0 0 4px 0;
  font-size: 15px;
  font-weight: 600;
}

.video-info p {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

/* --------------------------------------------------------------------------
   Microstructure Gallery & Charts
   -------------------------------------------------------------------------- */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 20px;
}

.gallery-grid.three {
  grid-template-columns: repeat(3, 1fr);
}

.gallery-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: transform 0.15s ease, border-color 0.15s ease;
}

.gallery-card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
}

.gallery-card .img-wrap {
  width: 100%;
  height: 220px;
  background: #F8FAFC;
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.gallery-card .img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.gallery-card .img-wrap img.fit-contain {
  object-fit: contain;
  background: #FFFFFF;
  padding: 6px;
}

.gallery-card .caption {
  padding: 12px 14px;
}

.gallery-card .caption h4 {
  margin: 0 0 4px 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}

.gallery-card .caption p {
  margin: 0;
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.4;
}

.chart-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px 20px 14px 20px;
  box-shadow: var(--shadow-sm);
}

.chart-card h4 {
  margin: 0 0 4px 0;
  font-size: 15px;
  font-weight: 600;
}

.chart-card p {
  margin: 0 0 14px 0;
  font-size: 13px;
  color: var(--muted);
}

.chart-card svg {
  width: 100%;
  height: auto;
  display: block;
}

/* --------------------------------------------------------------------------
   Publications & Patents
   -------------------------------------------------------------------------- */
.pub-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.pub-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
  box-shadow: var(--shadow-sm);
}

.pub-item .title {
  font-size: 14.5px;
  line-height: 1.55;
  color: var(--ink);
}

.pub-item .title i {
  font-style: italic;
}

.pub-item .meta {
  font-size: 12.5px;
  color: var(--muted);
  margin-top: 4px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}

.pub-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  color: var(--primary);
  border: 1px solid var(--primary-border);
  background: var(--primary-light);
  padding: 1px 7px;
  border-radius: var(--radius-sm);
}

.pub-tag.gold {
  color: var(--accent);
  background: var(--accent-light);
  border-color: var(--accent-border);
}

.pub-tag.green {
  color: #15803D;
  background: #F0FDF4;
  border-color: #BBF7D0;
}

.pub-tag.orange {
  color: #C2410C;
  background: #FFF7ED;
  border-color: #FFEDD5;
}

.pub-tag.blue {
  color: var(--primary);
  background: var(--primary-light);
  border-color: var(--primary-border);
}

/* --------------------------------------------------------------------------
   Skills & Instruments
   -------------------------------------------------------------------------- */
.two-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.skill-box {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.skill-box h4 {
  margin: 0 0 12px 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.skill-box ul {
  margin: 0;
  padding-left: 18px;
  font-size: 13.5px;
  color: var(--ink-light);
  line-height: 1.8;
}

/* --------------------------------------------------------------------------
   Timeline (Education & Honors)
   -------------------------------------------------------------------------- */
.timeline {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  position: relative;
}

.tl-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  box-shadow: var(--shadow-sm);
}

.tl-item .year {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.tl-item strong {
  display: block;
  font-size: 15px;
  margin-bottom: 4px;
}

.tl-item > span:not(.year) {
  font-size: 13px;
  color: var(--muted);
  display: block;
  line-height: 1.5;
}

.tl-courses {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.course-badge {
  display: inline-flex;
  align-items: baseline;
  gap: 3px;
  font-size: 11.5px;
  background: var(--ground);
  border: 1px solid var(--line);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  color: var(--ink-light);
  white-space: nowrap;
}

.course-badge span {
  font-size: 11.5px;
  color: var(--ink-light);
  line-height: 1.2;
}

.course-badge b {
  color: var(--primary);
  font-weight: 600;
}

/* Honors & Awards Section */
.honors-wrap {
  margin-top: 0;
}

.honors-title {
  font-size: 15.5px;
  font-weight: 700;
  color: var(--ink);
  margin: 0 0 12px 0;
  display: flex;
  align-items: center;
  gap: 8px;
}

.honors-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}

.honor-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  font-size: 13px;
  box-shadow: var(--shadow-sm);
}

.honor-card.gold {
  border-left: 3px solid var(--accent);
  background: #FFFDF9;
}

.honor-card .h-name {
  font-weight: 600;
  color: var(--ink);
  line-height: 1.4;
}

.honor-card .h-year {
  color: var(--muted);
  font-size: 11.5px;
  white-space: nowrap;
}

.activity-box {
  margin-top: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  box-shadow: var(--shadow-sm);
}

.activity-box h4 {
  margin: 0 0 10px 0;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 8px;
}

.activity-box ul {
  margin: 0;
  padding-left: 18px;
  font-size: 13px;
  color: var(--ink-light);
  line-height: 1.8;
}

.lead-subhead {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink);
  margin-top: 12px;
  margin-bottom: 8px;
}

.leadership-list {
  list-style: none !important;
  padding: 0 !important;
  margin: 0 0 14px 0 !important;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.leadership-card {
  background: var(--ground);
  border: 1px solid var(--line);
  border-left: 3.5px solid var(--primary);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.leadership-card:hover {
  border-color: #CBD5E1;
  border-left-color: var(--primary-dark);
  box-shadow: var(--shadow-sm);
}

.lead-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  margin-bottom: 5px;
}

.lead-role {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0.02em;
}

.lead-time {
  font-size: 11.5px;
  font-weight: 600;
  color: var(--primary);
  background: #EFF6FF;
  border: 1px solid #DBEAFE;
  padding: 2px 8px;
  border-radius: 4px;
  white-space: nowrap;
}

.lead-org {
  font-size: 13px;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 6px;
  line-height: 1.4;
}

.lead-desc {
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.55;
}

.traits-box {
  border-top: 1px dashed var(--line);
  padding-top: 12px;
  margin-top: 12px;
}

.traits-box ul {
  margin: 0;
  padding-left: 18px;
  font-size: 13px;
  color: var(--ink-light);
  line-height: 1.8;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
footer {
  padding: 34px 0 44px 0;
  background: #FFFFFF;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-meta {
  line-height: 1.6;
}

.footer-copy {
  font-weight: 600;
  color: var(--ink);
  font-size: 13.5px;
  margin-bottom: 4px;
}

.footer-contacts {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin: 5px 0;
  font-size: 12.5px;
}

.footer-citem {
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
}

.footer-citem a {
  color: var(--primary);
  text-decoration: none;
}

.footer-citem a:hover {
  text-decoration: underline;
}

.footer-dot {
  color: var(--line);
  font-weight: bold;
}

.footer-note {
  font-size: 11.5px;
  color: var(--muted);
  opacity: 0.8;
  margin-top: 4px;
}

.footer-icp {
  font-size: 11.5px;
  line-height: 1.5;
  margin-top: 2px;
}

.footer-icp a {
  color: var(--muted);
  text-decoration: none;
  opacity: 0.8;
  letter-spacing: 0.02em;
  transition: opacity 0.15s ease, color 0.15s ease;
}

.footer-icp a:hover {
  color: var(--primary);
  opacity: 1;
  text-decoration: underline;
}

.footer-action {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 8px;
}

.footer-sub-tag {
  font-size: 11.5px;
  color: var(--muted);
  opacity: 0.75;
}

/* --------------------------------------------------------------------------
   Modal Dialog
   -------------------------------------------------------------------------- */
dialog {
  border: none;
  border-radius: var(--radius-lg);
  padding: 0;
  max-width: 760px;
  width: calc(100% - 32px);
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  background: var(--surface);
  color: var(--ink);
  box-shadow: var(--shadow-lg);
}

dialog::backdrop {
  background: rgba(15, 23, 42, 0.55);
  backdrop-filter: blur(4px);
}

.dlg-body {
  padding: 24px;
}

.dlg-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 12px;
}

.dlg-header h3 {
  margin: 0;
  font-size: 18px;
  line-height: 1.4;
  color: var(--ink);
}

.dlg-close {
  width: 32px;
  height: 32px;
  min-width: 32px;
  min-height: 32px;
  border-radius: 50%;
  background: #F1F5F9;
  border: 1px solid #CBD5E1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 300;
  line-height: 1;
  color: var(--muted);
  cursor: pointer;
  transition: all 0.15s ease;
  padding: 0;
  margin: 0;
  -webkit-appearance: none;
  appearance: none;
  -webkit-tap-highlight-color: transparent !important;
  outline: none !important;
  box-shadow: none !important;
}

.dlg-close:hover,
.dlg-close:active {
  background: #E2E8F0;
  color: var(--ink);
  outline: none !important;
  box-shadow: none !important;
}

.dlg-close:focus,
.dlg-close:focus-visible {
  outline: none !important;
  box-shadow: none !important;
}

.dlg-concl {
  background: var(--primary-light);
  border-left: 3px solid var(--primary);
  padding: 12px 14px;
  margin: 0 0 16px 0;
  font-size: 14px;
  line-height: 1.65;
}

.dlg-content ul {
  padding-left: 20px;
  font-size: 13.5px;
  color: var(--ink-light);
  line-height: 1.8;
  margin-bottom: 18px;
}

.dlg-figs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.dlg-figs figure,
dialog figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: #FFFFFF;
}

.dlg-figs figure img,
dialog figure img {
  width: 100%;
  height: auto;
  max-height: 520px;
  display: block;
  object-fit: contain;
  background: #F8FAFC;
}

.dlg-figs figure.wide,
dialog figure.wide {
  grid-column: 1 / -1;
}

.dlg-figs figcaption,
dialog figcaption {
  font-size: 12.5px;
  color: var(--ink-light);
  padding: 8px 12px;
  border-top: 1px solid var(--line);
  background: #FAFCFF;
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Back to Top Floating Button (悬浮一键返回顶部)
   -------------------------------------------------------------------------- */
.back-to-top {
  position: fixed;
  right: 28px;
  bottom: 32px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--primary);
  color: #FFFFFF;
  border: 1px solid rgba(255, 255, 255, 0.25);
  box-shadow: 0 4px 16px rgba(18, 38, 63, 0.22);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px) scale(0.9);
  transition: opacity 0.25s ease, transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), background 0.2s ease, box-shadow 0.2s ease;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
}

.back-to-top:hover {
  background: var(--primary-dark);
  box-shadow: 0 8px 22px rgba(18, 38, 63, 0.32);
  transform: translateY(-3px) scale(1.05);
}

.back-to-top:active {
  transform: translateY(0) scale(0.95);
  box-shadow: 0 2px 8px rgba(18, 38, 63, 0.25);
}

/* --------------------------------------------------------------------------
   Mobile-First Responsive Adjustments (微信扫码优化)
   -------------------------------------------------------------------------- */
@media (max-width: 820px) {
  .menu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.45);
    border-radius: var(--radius-sm);
    color: #FFFFFF;
    padding: 5px 8px;
    cursor: pointer;
    line-height: 1;
    margin-right: 10px;
    transition: background 0.15s ease, border-color 0.15s ease;
  }

  .menu-toggle:hover,
  .menu-toggle:active {
    background: rgba(255, 255, 255, 0.18);
    border-color: #FFFFFF;
  }

  .menu-toggle .icon-close {
    display: none;
  }

  .nav.is-open .menu-toggle .icon-menu {
    display: none;
  }

  .nav.is-open .menu-toggle .icon-close {
    display: block;
  }

  .nav .wrap {
    height: 52px !important;
    padding: 0 16px !important;
    display: flex !important;
    align-items: center !important;
    justify-content: space-between !important;
    position: relative;
  }

  .nav .nav-right {
    display: flex !important;
    align-items: center !important;
  }

  .nav .links {
    display: none !important;
    position: absolute;
    top: 52px;
    left: 0;
    width: 100%;
    background: rgba(23, 61, 110, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    box-shadow: 0 14px 30px rgba(0, 0, 0, 0.35);
    flex-direction: column !important;
    padding: 6px 0 !important;
    gap: 0 !important;
    z-index: 101;
  }

  .nav.is-open .links {
    display: flex !important;
    animation: navSlideDown 0.22s cubic-bezier(0.16, 1, 0.3, 1) forwards;
  }

  @keyframes navSlideDown {
    from {
      opacity: 0;
      transform: translateY(-8px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  .nav .links a {
    padding: 12px 20px !important;
    font-size: 14.5px !important;
    color: rgba(255, 255, 255, 0.95) !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08) !important;
    border-radius: 0 !important;
    background: transparent !important;
    display: flex !important;
    align-items: center;
    justify-content: space-between;
    text-decoration: none;
    line-height: 1.3 !important;
    transition: background 0.15s ease, padding-left 0.15s ease;
  }

  .nav .links a:last-child {
    border-bottom: none !important;
  }

  .nav .links a:active,
  .nav .links a:hover {
    background: rgba(255, 255, 255, 0.12) !important;
    padding-left: 24px !important;
    color: #FFFFFF !important;
  }

  .nav .links a::after {
    content: "›";
    font-size: 17px;
    opacity: 0.6;
    font-weight: 300;
  }

  section {
    scroll-margin-top: 64px;
  }

  .back-to-top {
    right: 18px;
    bottom: 24px;
    width: 42px;
    height: 42px;
    box-shadow: 0 4px 14px rgba(15, 23, 42, 0.3);
  }

  .hero {
    padding: 20px 0 16px 0;
  }

  .hero-grid {
    display: block;
  }

  .desktop-photo {
    display: none;
  }

  .mobile-photo {
    display: block;
    width: 118px;
    height: 152px;
    flex-shrink: 0;
    border-radius: var(--radius-md);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    background: #FFFFFF;
  }

  .wrap {
    padding: 0 16px;
  }

  .hero-header-row {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 14px;
  }

  .hero-identity-text {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 6px;
    box-sizing: border-box;
    padding: 0;
    margin: 0;
  }

  .hero-name-row {
    display: flex;
    align-items: baseline;
    justify-content: flex-start;
    gap: 8px;
    margin: 0;
    width: 100%;
    line-height: 1;
  }

  .hero-name {
    font-size: 25px;
    font-weight: 700;
    margin: 0;
    line-height: 1.1;
    color: var(--ink);
  }

  .hero-degree {
    font-size: 15px;
    font-weight: 600;
    color: var(--primary);
    line-height: 1;
    letter-spacing: 0.04em;
    padding: 2px 7px;
    background: var(--primary-light);
    border: 1px solid var(--primary-border);
    border-radius: var(--radius-sm);
  }

  .hero-dept-val {
    font-size: 13px;
    color: var(--ink-light);
    font-weight: 600;
    line-height: 1.35;
    letter-spacing: 0.01em;
    text-align: left;
    width: 100%;
    margin: 0 0 2px 0;
    white-space: normal;
  }

  html.en .hero-dept-val {
    font-size: 11px;
    white-space: normal;
  }

  .hero-contacts {
    display: flex;
    flex-direction: column;
    gap: 5px;
    flex-wrap: nowrap;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    width: 100%;
    align-items: flex-start;
  }

  .hero-c-item {
    display: flex;
    align-items: baseline;
    justify-content: flex-start;
    font-size: 12px;
    color: var(--ink);
    line-height: 1.3;
    text-decoration: none;
    margin: 0;
    padding: 0;
    white-space: nowrap;
    text-align: left;
    width: 100%;
  }

  .hero-c-item:hover,
  .hero-c-item:active {
    color: var(--primary);
  }

  .hero-c-item .c-lbl {
    display: inline-block;
    width: 3.0em;
    flex-shrink: 0;
    color: var(--muted);
    font-weight: 500;
    text-align: left;
  }

  .hero-c-item .c-val {
    flex: 1;
    font-size: 12px;
    font-weight: 500;
    color: var(--ink);
    text-align: left;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .hero-c-item.hero-c-addr .c-lbl {
    font-size: 11px;
    width: 3.0em;
  }

  .hero-c-item.hero-c-addr .c-val {
    font-size: 11px;
    letter-spacing: -0.01em;
    text-align: left;
    white-space: normal;
    line-height: 1.3;
  }

  .hero-title {
    margin: 0 0 8px 0;
    font-size: 14px;
    line-height: 1.5;
  }

  .hero-bio {
    font-size: 13.5px;
    line-height: 1.65;
    margin: 0;
  }

  .proof-banner .wrap {
    grid-template-columns: 1fr;
    padding: 0;
  }

  .proof-tile {
    border-right: none;
    border-bottom: 1px solid var(--line);
    min-height: auto;
    padding: 12px 16px;
  }

  .proof-tile:last-child {
    border-bottom: none;
  }

  .video-grid,
  .cards-grid,
  .cards-grid.three,
  .gallery-grid,
  .gallery-grid.three,
  .two-cols,
  .timeline,
  .honors-grid {
    grid-template-columns: 1fr;
  }

  .dlg-figs {
    grid-template-columns: 1fr;
  }

  .pub-item {
    grid-template-columns: 1fr;
  }

  .gallery-card .img-wrap {
    height: 200px;
  }

  /* Mobile Footer Refinements */
  footer {
    padding: 26px 0 64px 0 !important;
  }

  .footer-content {
    flex-direction: column !important;
    align-items: flex-start !important;
    gap: 12px !important;
  }

  .footer-copy {
    font-size: 13px !important;
    line-height: 1.45 !important;
    margin-bottom: 6px !important;
  }

  .footer-contacts {
    flex-direction: column !important;
    align-items: flex-start !important;
    gap: 6px !important;
    margin: 6px 0 !important;
    width: 100% !important;
  }

  .footer-dot {
    display: none !important;
  }

  .footer-citem {
    font-size: 12.5px !important;
    display: flex !important;
    align-items: baseline !important;
    width: 100% !important;
  }

  .footer-lbl {
    color: var(--muted) !important;
    display: inline-block !important;
    width: 68px !important;
    flex-shrink: 0 !important;
  }

  .footer-val {
    color: var(--primary) !important;
    font-weight: 500 !important;
  }

  .footer-note {
    font-size: 11px !important;
    line-height: 1.4 !important;
    margin-top: 4px !important;
  }

  .footer-icp {
    font-size: 11px !important;
    line-height: 1.4 !important;
    margin-top: 2px !important;
  }

  .footer-action {
    display: flex !important;
    flex-direction: row !important;
    justify-content: space-between !important;
    align-items: center !important;
    width: 100% !important;
    padding-top: 12px !important;
    border-top: 1px dashed var(--line) !important;
    margin-top: 6px !important;
  }
}