/* Fallback font source */
@import url('https://fonts.font.im/css2?family=Inter:wght@300;400;500;600;700&family=Source+Serif+4:opsz,wght@8..60,400;8..60,600;8..60,700&display=swap');

/* ========== CSS Variables ========== */
:root {
  --primary: #4a90d9;
  --primary-light: #e8f0fe;
  --primary-dark: #2d6cb5;
  --bg: #ffffff;
  --bg-alt: #f5f8fc;
  --text: #2c3e50;
  --text-light: #64748b;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.05), 0 2px 4px rgba(0, 0, 0, 0.03);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.08);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: 0.3s ease;
  --max-width: 960px;
  /* 英文：Inter / Source Serif；中文缺字时回退到楷体 */
  --font-kaiti: 'KaiTi', '楷体', 'STKaiti', 'Kaiti SC', 'Kaiti TC', serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, var(--font-kaiti);
  --font-serif: 'Source Serif 4', Georgia, var(--font-kaiti);
  --font-cn: var(--font-kaiti);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

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

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

strong {
  font-weight: 600;
}

/* ========== Container ========== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== Navigation ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow var(--transition);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-logo {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
}

.nav-logo:hover {
  color: var(--primary);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 28px;
}

.nav-links a {
  color: var(--text-light);
  font-size: 0.9rem;
  font-weight: 500;
  position: relative;
  padding: 4px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width var(--transition);
  border-radius: 1px;
}

.nav-links a:hover {
  color: var(--primary);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: var(--transition);
}

/* ========== Hero ========== */
.hero {
  padding: 100px 0 24px;
  background: linear-gradient(180deg, var(--primary-light) 0%, var(--bg) 100%);
}

.hero-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 60px;
}

.hero-text {
  flex: 1;
}

.hero-greeting {
  font-size: 1rem;
  color: var(--primary);
  font-weight: 500;
  margin-bottom: 8px;
}

.hero-name {
  font-family: var(--font-serif);
  font-size: 2.75rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.2;
  margin-bottom: 12px;
}

.hero-name-cn {
  font-family: var(--font-cn);
  font-size: 2.85rem;
  font-weight: 400;
  letter-spacing: 0.05em;
}

.hero-alias {
  color: var(--primary);
  font-weight: 600;
}

.hero-title {
  font-size: 1.2rem;
  color: var(--text-light);
  font-weight: 500;
  margin-bottom: 4px;
}

.hero-affiliation {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 28px;
}

.hero-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition);
  border: 1.5px solid transparent;
}

.btn-outline {
  background: var(--bg);
  color: var(--text);
  border-color: var(--border);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  box-shadow: var(--shadow);
}

/* ========== Avatar ========== */
.hero-avatar {
  flex-shrink: 0;
}

.avatar-img {
  width: 280px;
  height: 280px;
  border-radius: var(--radius-lg);
  object-fit: cover;
  border: 4px solid #fff;
  box-shadow: var(--shadow-lg);
}

/* ========== Sections ========== */
.section {
  padding: 80px 0;
}

/* 首屏与 About 之间留白收紧（仅 About 区块顶部） */
#about.section {
  padding-top: 20px;
}

.section-alt {
  background: var(--bg-alt);
}

.section-title {
  font-family: var(--font-serif);
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 40px;
  color: var(--text);
  position: relative;
  padding-bottom: 12px;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 3px;
  background: var(--primary);
  border-radius: 2px;
}

/* ========== About ========== */
.about-content {
  display: grid;
  gap: 40px;
}

.about-text p {
  margin-bottom: 16px;
  font-size: 1rem;
  color: var(--text);
}

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

.about-info {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.info-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
}

.info-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.info-card h3 i {
  color: var(--primary);
  font-size: 0.9rem;
}

/* ========== Education ========== */
.edu-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.edu-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}

.edu-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.edu-item:first-child {
  padding-top: 0;
}

.edu-logo {
  width: 42px;
  height: 42px;
  flex-shrink: 0;
  object-fit: contain;
  margin-top: 2px;
}

.edu-detail {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* 首行：学校 / 单位；次行：学位 / 职位 */
.edu-detail strong {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
}

.edu-detail span {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-light);
}

.edu-time {
  font-size: 0.84rem;
  font-style: normal;
  color: var(--text-muted);
}

/* ========== News ========== */
.news-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.news-item {
  display: flex;
  align-items: baseline;
  gap: 20px;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}

.news-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.news-item:first-child {
  padding-top: 0;
}

.news-date {
  flex-shrink: 0;
  width: 80px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
}

.news-text {
  font-size: 0.95rem;
  color: var(--text);
}

/* ========== Publications ========== */
.pub-year-title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--primary-dark);
  margin-top: 36px;
  margin-bottom: 16px;
  padding-left: 12px;
  border-left: 3px solid var(--primary);
}

.pub-year-title:first-of-type {
  margin-top: 0;
}

.publications-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 8px;
}

.pub-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  transition: box-shadow var(--transition), transform var(--transition);
}

.section-alt .pub-card {
  background: var(--bg);
}

.pub-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.pub-venue {
  margin-bottom: 10px;
}

.venue-badge {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  padding: 3px 12px;
  border-radius: 4px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.pub-title {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
  line-height: 1.4;
  color: var(--text);
}

.pub-authors {
  font-size: 0.88rem;
  color: var(--text-light);
  margin-bottom: 10px;
}

.pub-journal {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-style: italic;
  margin-bottom: 10px;
}

.pub-links {
  display: flex;
  gap: 16px;
}

.pub-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--primary);
}

.pub-link:hover {
  color: var(--primary-dark);
}

/* ========== Services ========== */
.services-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.service-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.service-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.service-card h3 i {
  color: var(--primary);
}

.service-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.service-list li {
  font-size: 0.9rem;
  color: var(--text-light);
  padding-left: 16px;
  position: relative;
}

.service-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary-light);
  border: 1.5px solid var(--primary);
}

/* ========== Awards ========== */
.awards-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.award-card {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px;
}

.award-icon {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, #fef3c7, #fde68a);
  display: flex;
  align-items: center;
  justify-content: center;
}

.award-icon i {
  font-size: 1.1rem;
  color: #d97706;
}

.award-content h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 2px;
  color: var(--text);
}

.award-content p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ========== Footer ========== */
.footer {
  padding: 32px 0;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ========== Animations ========== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========== Responsive ========== */
@media (max-width: 768px) {
  body {
    font-size: 16px;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 20px 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
  }

  .nav-links.active {
    display: flex;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-container {
    flex-direction: column-reverse;
    text-align: center;
    gap: 32px;
  }

  .hero-name {
    font-size: 2rem;
  }

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

  .avatar-img {
    width: 220px;
    height: 220px;
  }

  .about-info {
    grid-template-columns: 1fr;
  }

  .edu-item {
    flex-direction: column;
    gap: 8px;
  }

  .edu-logo {
    width: 36px;
    height: 36px;
  }

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

  .awards-list {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 60px 0;
  }
}

@media (max-width: 480px) {
  .hero-name {
    font-size: 1.75rem;
  }

  .hero-links {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .news-item {
    flex-direction: column;
    gap: 4px;
  }

  .news-date {
    width: auto;
  }
}