:root {
  --primary: #6a0dad;
  --primary-dark: #4b0082;
  --primary-light: #9370db;
  --secondary: #f0e6ff;
  --accent: #ffd700;
  --text: #333333;
  --text-light: #666666;
  --background: #ffffff;
  --section-bg: #f9f7fd;

  /* Lato字体大小定义 */
  --font-thin: 100;
  --font-light: 300;
  --font-regular: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  --font-black: 900;

  /* Lato字体大小定义 */
  --font-size-xs: 0.75rem;   /* 12px */
  --font-size-sm: 0.875rem;  /* 14px */
  --font-size-base: 1rem;    /* 16px */
  --font-size-lg: 1.125rem;  /* 18px */
  --font-size-xl: 1.25rem;   /* 20px */
  --font-size-2xl: 1.5rem;   /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem;  /* 36px */
  --font-size-5xl: 3rem;     /* 48px */
}

/* 本地Lato字体定义 - 替换Google Fonts导入 */
@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Thin.ttf') format('truetype');
  font-weight: 100;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-ThinItalic.ttf') format('truetype');
  font-weight: 100;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Light.ttf') format('truetype');
  font-weight: 300;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-LightItalic.ttf') format('truetype');
  font-weight: 300;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Italic.ttf') format('truetype');
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Bold.ttf') format('truetype');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-BoldItalic.ttf') format('truetype');
  font-weight: 700;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-Black.ttf') format('truetype');
  font-weight: 900;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Lato';
  src: url('./fonts/Lato-BlackItalic.ttf') format('truetype');
  font-weight: 900;
  font-style: italic;
  font-display: swap;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Lato', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
  font-weight: var(--font-regular);
  font-size: var(--font-size-base);
}

body {
  color: var(--text);
  line-height: 1.6;
  background-color: var(--background);
  overflow-x: hidden;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 标题字体设置 */
h1 {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-black);
  line-height: 1.2;
  margin-bottom: 1rem;
}

h2 {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-bold);
  line-height: 1.3;
  margin-bottom: 0.875rem;
}

h3 {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-semibold);
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

h4 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-semibold);
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

h5 {
  font-size: var(--font-size-lg);
  font-weight: var(--font-medium);
  line-height: 1.5;
  margin-bottom: 0.5rem;
}

h6 {
  font-size: var(--font-size-base);
  font-weight: var(--font-medium);
  line-height: 1.5;
  margin-bottom: 0.5rem;
}

/* 段落和正文文本 */
p {
  font-size: var(--font-size-base);
  font-weight: var(--font-regular);
  line-height: 1.6;
  margin-bottom: 1rem;
}

.lead-text {
  font-size: var(--font-size-lg);
  font-weight: var(--font-light);
  line-height: 1.7;
}

.small-text {
  font-size: var(--font-size-sm);
  font-weight: var(--font-regular);
  line-height: 1.5;
}

.caption-text {
  font-size: var(--font-size-xs);
  font-weight: var(--font-light);
  line-height: 1.4;
  color: var(--text-light);
}

header {
  height: 90px; /* 增加高度以容纳两行文字 */
  background-color: var(--background);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: fixed;
  width: 100%;
  top: 0;
  z-index: 1000;
}
.logo-container {
  display: flex;
  align-items: center;
  gap: 30px;
}

.lab-logo-section {
  display: flex;
  align-items: center;
  gap: 15px;
  padding-right: 25px;
  border-right: 2px solid var(--secondary);
}

.logo-image {
  width: 60px;
  height: 60px;
  flex-shrink: 0;
}

.logo-image img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}
.logo-acronym {
  color: var(--background);
  font-size: var(--font-size-lg);
  font-weight: var(--font-bold);
  letter-spacing: 1px;
}

/* 实验室名称 */
.lab-name {
  display: flex;
  flex-direction: column;
  font-size: var(--font-size-sm);
  font-weight: var(--font-semibold);
  color: var(--text);
  line-height: 1.2;
  white-space: nowrap;
}

.lab-name span {
  display: block;
}

.comenius-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-semibold);
  color: var(--primary);
  line-height: 1.2;
  white-space: nowrap;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 0;
  height: 100%;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-black);
  color: var(--primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 25px;
}

.nav-links li {
  /*margin-left: 45px;*/
}

.nav-links a {
  text-decoration: none;
  color: var(--text);
  font-size: var(--font-size-lg);
  font-weight: var(--font-semibold);
  transition: color 0.3s;
  position: relative;
}

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

.nav-links a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -5px;
  left: 0;
  background-color: var(--primary);
  transition: width 0.3s;
}

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

.mobile-menu {
  display: none;
  font-size: var(--font-size-2xl);
  cursor: pointer;
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: white;
  padding: 70px 0 100px;
  text-align: center;
  margin-top: 70px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero h1 {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-black);
  margin-bottom: 20px;
}

.hero p {
  font-size: var(--font-size-lg);
  font-weight: var(--font-light);
  max-width: 700px;
  margin: 0 auto 25px;
  opacity: 0.9;
  line-height: 1.6;
}

/* Section Styling */
section {
  padding: 80px 0;
}

.btn {
    display: inline-block;
    background-color: var(--background);
    color: var(--primary);
    padding: 0.8rem 1.5rem;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.btn:hover {
    background-color: rgba(255, 255, 255, 0.9);
    transform: translateY(-2px);
}

.seminar-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-semibold);
  color: var(--primary);
  line-height: 1.2;
  white-space: nowrap;
}

.section-title {
  text-align: center;
  margin-bottom: 50px;
}

.section-title h2 {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-bold);
  color: var(--text);
  margin-bottom: 15px;
  position: relative;
  display: inline-block;
}

.section-title h2::after {
  content: '';
  position: absolute;
  width: 50px;
  height: 3px;
  background: var(--primary);
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
}

.section-title p {
  font-size: var(--font-size-base);
  font-weight: var(--font-light);
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* Features Section 样式 */
.features-section {
  padding: 60px 0; /* 保持适当间距 */
  background-color: var(--background);
  min-height: auto;
}


/* 卡片链接样式 */
.card-link {
  text-decoration: none;
  color: inherit;
  display: block;
  transition: transform 0.3s ease;
}

.card-link:hover {
  transform: translateY(-5px);
}

/* 卡片布局 */
.cards-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem; /* 减少卡片间距 */
  max-width: 1200px;
  margin: 0 auto;
}

.card {
  background: var(--background);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  border: 1px solid rgba(106, 13, 173, 0.1);
  height: 100%;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px rgba(106, 13, 173, 0.15);
}

.card-img {
    height: 200px;
    background-color: var(--background);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    object-fit: cover;
}

.card-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.card-content {
    padding: 1.5rem;
}

.card h3 {
    margin-bottom: 1rem;
    color: var(--text);
    font-size: var(--font-size-xl);
}

/* Page Content */
.page-content {
  padding-top: 120px;
  min-height: calc(100vh - 70px);
}

/* Previous Talks Page */
.talks-list {
  display: flex;
  flex-direction: column;
  gap: 30px;
  max-width: 1000px;
  margin: 0 auto;
}

.talk-list-item {
  background: white;
  width: 1050px;
  border-radius: 16px;
  box-shadow: 5px 10px 15px rgba(0, 0, 0, 0.05);
  padding: 20px;
  display: flex;
  gap: 20px;
  transition: transform 0.3s;
  align-items: center;
}

.talk-list-item:hover {
  transform: translateY(-5px);
}

.talk-list-item .talk-cover {
  width: 250px;
  height: 200px;
  border-radius: 16px;
  overflow: hidden;
  flex-shrink: 0;
}

.talk-list-item .talk-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.talk-list-item .talk-cover video{
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}
.talk-info {
  flex: 1;
}

.talk-list-item .talk-date {
  font-size: var(--font-size-sm);
  font-weight: var(--font-semibold);
  margin-bottom: 8px;
}

.talk-list-item .talk-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-bold);
  margin-bottom: 4px;
  color: var(--primary-dark);
}

.talk-list-item .talk-speaker {
  font-size: var(--font-size-base);
  font-weight: var(--font-semibold);
  margin-bottom: 4px;
  color: var(--text);
}

.talk-list-item p {
  width: 90%;
  font-size: var(--font-size-base);
  font-weight: var(--font-medium);
  margin-bottom: 8px;
  color: var(--text-light);
  text-align: justify;
}

.talk-list-item .talk-link{
  color: var(--primary);
  font-size: var(--font-size-sm);
  font-weight: var(--font-bold);
  text-decoration: none;
  margin-top: -5px;
  transition: all 0.3s ease;
  display: inline-block;
}

.talk-list-item .talk-link:hover {
  color: var(--primary-dark);
  font-weight: var(--font-bold);
  text-decoration: None;
}


/* Footer */
footer {
  background: var(--primary-dark);
  color: white;
  padding: 50px 0 20px;
  margin-top: 50px;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 300px;
  margin-bottom: 30px;
}

.footer-column h3 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-bold);
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}

.footer-column h3::after {
  content: '';
  position: absolute;
  width: 40px;
  height: 2px;
  background: white;
  bottom: 0;
  left: 0;
}

.footer-column p, .footer-column a {
  font-size: var(--font-size-base);
  font-weight: var(--font-regular);
  margin-bottom: 10px;
  display: block;
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  transition: color 0.3s;
}

.footer-column a:hover {
  color: white;
}

.footer-column form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-column button {
  background: var(--primary-light);
  color: white;
  border: none;
  padding: 10px;
  border-radius: 5px;
  cursor: pointer;
  font-size: var(--font-size-base);
  font-weight: var(--font-semibold);
  transition: background 0.3s;
}

.footer-column button:hover {
  background: var(--primary);
}

.footer-bottom {
  text-align: center;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: var(--font-size-sm);
  font-weight: var(--font-light);
  color: rgba(255, 255, 255, 0.7);
}

/* Google Form */
.google-form-link {
  display: inline-flex;
  align-items: center;
  gap: 20px;
  background: var(--primary-light);
  color: white;
  padding: 12px 20px;
  border-radius: 5px;
  text-decoration: none;
  font-weight: var(--font-semibold);
  transition: background 0.3s;
  margin-top: 15px;
  width: 80%;
  text-align: center;
}

.google-form-link:hover {
  background: #7e57c2;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(147, 112, 219, 0.25);
}

.google-form-link i {
  font-size: var(--font-size-lg);
  /*transition: transform 0.3s ease;*/
}

.google-form-link:hover i {
  transform: scale(1.1);
}

.form-description {
  font-size: var(--font-size-sm);
  color: var(--text-light);
  margin-top: 10px;
  line-height: 1.4;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background: white;
    flex-direction: column;
    padding: 20px;
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
  }

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

  .nav-links li {
    margin: 10px 0;
  }

  .mobile-menu {
    display: block;
  }

  .hero h1 {
    font-size: var(--font-size-3xl);
  }

  .talk-card {
    flex-direction: column;
    text-align: center;
  }

  .talk-cover {
    flex: 0 0 auto;
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
  }

  .talk-list-item {
    flex-direction: column;
  }

  .talk-list-item .talk-cover {
    width: 100%;
    height: 200px;
  }

  /* 移动端字体调整 */
  h1 {
    font-size: var(--font-size-3xl);
  }

  h2 {
    font-size: var(--font-size-2xl);
  }

  h3 {
    font-size: var(--font-size-xl);
  }

  .hero p {
    font-size: var(--font-size-base);
  }
}

/* 新的两栏布局样式 */
.split-layout {
  position: relative;
  min-height: 80vh;
  display: flex;
  flex-direction: column;
}

.top-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: var(--background);
  min-height: 50vh; /* 占据60%的视口高度 */
  display: flex;
  align-items: center;
  position: relative;
  flex: 5;
  padding: 4rem 0;
  margin-bottom: -2rem;
}

.bottom-section {
  background: var(--background);
  min-height: 50vh; /* 占据40%的视口高度 */
  display: flex;
  align-items: center;
  position: relative;
  flex: 5;
  margin-bottom: -5rem;
}

.hero-content {
  text-align: center;
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 20px;
  width: 100%;
}

.hero-content h1 {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-black);
  margin-bottom: 1.5rem;
  line-height: 1.3;
}

.hero-content h2 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-light);
  margin-bottom: 2rem;
  opacity: 0.9;
  line-height: 1.5;
}

/* Learn More 按钮 - 重新定位到内容内部 */
.learn-more-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.8rem;
  background: var(--accent);
  color: var(--primary-dark);
  padding: 1rem 2rem;
  border-radius: 50px;
  text-decoration: none;
  font-weight: var(--font-bold);
  transition: all 0.1s ease;
  /*border: 3px solid var(--primary-light);*/
  font-size: var(--font-size-lg);
  white-space: nowrap;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
  position: relative;
  overflow: hidden;
  margin-top: 10px;
}

.learn-more-btn:hover {
  transform: translateY(-2px) scale(1.05);
  background: #ffdf00;
  box-shadow: 0 4px 20px rgba(255, 215, 0, 0.4);
  border-color: white;
}

.learn-more-btn i {
  transition: transform 0.01s ease;
}

.project-info {
  font-size: var(--font-size-xl);
  font-weight: var(--font-black);
  color: var(--accent);
}

/* 资金支持机构部分 - 更新样式 */
.funding-section {
  text-align: center;
  width: 100%;
  padding: 0 20px;
}

.funding-section h3 {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-black);
  color: var(--text-light);
  margin-top: -6rem;
  margin-bottom: 3rem;
  text-transform: uppercase;
  letter-spacing: 2px;
}

.logos-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 4rem;
  max-width: 1000px;
  margin: 0 auto;
}

.logo-link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.logo-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 200px;
  background: var(--section-bg);
  border-radius: 16px;
  transition: all 0.3s ease;
  border: 2px solid transparent;
  padding: 2rem;
  text-align: center;
  position: relative;
  cursor: pointer;
}

.logo-item:hover {
  transform: translateY(-5px);
  border-color: var(--primary-light);
  box-shadow: 0 15px 35px rgba(106, 13, 173, 0.15);
}

.logo-image-container {
  height: 80px;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.funding-logo {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
}


.logo-text {
  font-size: var(--font-size-base);
  font-weight: var(--font-semibold);
  color: var(--primary);
  line-height: 1.4;
}

.link-indicator {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: var(--primary-light);
  color: white;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-sm);
  opacity: 0;
  transform: scale(0.8);
  transition: all 0.3s ease;
}

.logo-item:hover .link-indicator {
  opacity: 1;
  transform: scale(1);
}

.link-indicator i {
  transition: transform 0.3s ease;
}

.logo-item:hover .link-indicator i {
  transform: translate(1px, -1px);
}

/* 点击效果 */
.logo-item:active {
  transform: translateY(-2px) scale(0.98);
  transition: transform 0.1s ease;
}


/* 响应式设计调整 */
@media (max-width: 768px) {
  .logos-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .logo-item {
    height: 180px;
    padding: 1.5rem;
  }

  .logo-image-container {
    height: 60px;
    margin-bottom: 1rem;
  }

  .logo-text {
    font-size: var(--font-size-sm);
  }

  .link-indicator {
    top: 0.8rem;
    right: 0.8rem;
    width: 25px;
    height: 25px;
    font-size: var(--font-size-xs);
  }
}

@media (max-width: 480px) {
  .logo-item {
    height: 160px;
    padding: 1rem;
  }

  .logo-image-container {
    height: 50px;
    margin-bottom: 0.8rem;
  }

  .logo-text {
    font-size: var(--font-size-xs);
  }
}


/* 响应式设计 */
@media (max-width: 768px) {
  .split-layout {
    min-height: 100vh;
  }

  .top-section, .bottom-section {
    height: 50vh;
  }

  .hero-content h1 {
    font-size: var(--font-size-2xl);
  }

  .hero-content h2 {
    font-size: var(--font-size-lg);
  }

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

  .logo-item {
    height: 100px;
  }

}

@media (max-width: 480px) {
  .logos-grid {
    grid-template-columns: 1fr;
  }

  .hero-content h1 {
    font-size: var(--font-size-xl);
  }

  .hero-content h2 {
    font-size: var(--font-size-base);
  }


}

@media (max-width: 480px) {
  .logos-grid {
    grid-template-columns: 1fr;
  }

  .hero-content h1 {
    font-size: var(--font-size-xl);
  }

  .hero-content h2 {
    font-size: var(--font-size-base);
  }
}

/* 首页容器 */
.homepage-container {
  width: 100%;
}

/* About Section 样式 */
.about-section {
  padding: 80px 0;
  background: linear-gradient(135deg, var(--section-bg) 0%, var(--background) 100%);
  min-height: auto;
}

.about-content {
  max-width: 1200px;
  margin: 0 auto;
}

.about-text p {
  font-size: var(--font-size-lg);
  line-height: 1.8;
  margin-bottom: 2rem;
  text-align: center;
  color: var(--text);
}

/* 作者信息 */
.talk-author {
  margin-top: -5px;
  margin-bottom: -10px;
}

.author-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text);
  text-decoration: none;
  font-size: var(--font-size-base);
  font-weight: var(--font-medium);
  transition: color 0.3s ease;
  padding: 4px 0;
}

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

.author-link i {
  font-size: var(--font-size-sm);
  opacity: 0.7;
}