/* Global Styles */
:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #2c3e50;
    --light-bg: #f8f9fa;
    --dark-bg: #2c3e50;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
}

/* Navigation */
.navbar {
    background-color: rgba(44, 62, 80, 0.6);
    padding: 1rem 0;
    transition: all 0.3s ease;
    box-shadow: none;
}

.navbar.scrolled {
    background-color: #fff;
    box-shadow: 0 2px 12px rgba(44, 62, 80, 0.08);
}

.navbar .navbar-brand,
.navbar .nav-link {
    color: #fff !important;
    transition: color 0.3s;
}

.navbar .nav-link.active {
    color: var(--secondary-color) !important;
}

/* Remove color change for .scrolled nav links except .active */
.navbar.scrolled .navbar-brand {
    color: #fff !important;
}

.navbar.scrolled .nav-link.active {
    color: var(--secondary-color) !important;
}

.navbar .navbar-brand {
    font-size: 1.8rem;
    font-weight: bold;
    color: #fff !important;
}

.navbar .nav-link {
    font-size: 1.15rem;
    font-weight: 500;
    padding: 0.5rem 1.2rem !important;
}

/* Hero Section */
.hero-section {
    background: none;
    color: white;
    padding: 0;
    position: relative;
    overflow: hidden;
    height: 70vh;
    min-height: 500px;
    display: flex;
    flex-direction: column;
    /* max-height: 150vh; 
    justify-content: center; 
    z-index: 1; */
} 
/* 响应式字体缩放 */
/* @media (max-width: 768px) {
    .hero-section h1.display-4 {
      font-size: 2rem;
    }
    .hero-section h2.h3 {
      font-size: 1.25rem;
    }
    .hero-section .lead {
      font-size: 1rem;
    }
  } */

.hero-content {
    position: relative;
    z-index: 2;
    padding: 9rem 0 2rem 0;
    /* background: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0)); */
}

/* Remove the pattern background */
.hero-section::before {
    display: none;
}

.hero-section h1,
.hero-section h2,
.hero-section p,
.hero-section .lead {
    text-shadow: 0 2px 8px rgba(0,0,0,0.45);
}

.hero-section h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.hero-section h2 {
    font-size: 1.4rem;
    margin-bottom: 1.5rem;
    opacity: 0.9;
}

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

.section-title {
    text-align: center;
    margin-bottom: 3rem;
    color: var(--primary-color);
    font-weight: 700;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--secondary-color);
    margin: 1rem auto;
}

/* Timeline */
.timeline {
    position: relative;
    padding: 2rem 0;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    margin-left: 60px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: var(--secondary-color);
    border-radius: 2px;
}

.timeline-item {
    display: flex;
    align-items: center;
    margin-bottom: 2.5rem;
    position: relative;
    min-height: 40px;
}

.timeline-marker {
    position: relative;
    left: -12px;
    width: 24px;
    height: 24px;
    background: #fff;
    border: 4px solid var(--secondary-color);
    border-radius: 50%;
    z-index: 2;
    box-sizing: border-box;
    margin-right: 24px;
}

.timeline-item .date {
    width: 170px;
    font-weight: bold;
    color: var(--secondary-color);
    white-space: nowrap;
    text-align: left;
    margin-right: 1.5rem;
    font-size: 1.15rem;
}

.timeline-item .content {
    flex: 1;
    font-size: 1.1rem;
    padding-left: 0;
}

.timeline-item:last-child {
    margin-bottom: 0;
}
.timeline-item .extended {
    font-size: 0.85em;
    color: #d9534f; /* 红色或者你想要的颜色 */
    font-weight: normal;
}

/* Program Schedule */
.program-schedule {
    margin-top: 2rem;
}

.program-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.program-item.center-time {
    align-items: center;
}

.program-item .time {
    width: 100px;
    font-weight: bold;
    color: var(--secondary-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    line-height: 1.3;
    flex-shrink: 0;
}

.program-item .time-separator {
    font-size: 1.5rem;
    opacity: 0.6;
    margin: 2px 0;
    color: var(--secondary-color);
    font-weight: 600;
}

.program-item .content {
    flex: 1;
}

/* Paper List Styles */
.paper-list .paper-item p strong {
    font-weight: 600;
    color: #495057;
}

.paper-list .paper-item .text-muted {
    font-style: italic;
}

/* Committee Members */
.committee-members {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
    /* text-decoration: none; */
}
.committee-members a {
    text-decoration: none;
  }

.member {
    text-align: center;
    padding: 1.5rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.member h4 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    /* text-decoration: none; */
}

/* Topic List */
.topic-list {
    list-style: none;
    padding: 0;
}

.topic-list li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.topic-list li::before {
    content: '•';
    color: var(--secondary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

/* Sponsors */
.sponsor {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.sponsor-logo {
    max-width: 300px;
    margin-bottom: 1rem;
    padding: 1rem;
    background: white;
    border-radius: 4px;
}

.sponsor-logo img {
    max-height: 80px;
    width: auto;
    object-fit: contain;
}

.sponsor-info {
    text-align: center;
}

.sponsor-info h4 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.sponsor-info p {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.sponsor-description {
    font-size: 0.9rem;
    color: #666;
    max-width: 600px;
    margin: 1rem auto 0;
    line-height: 1.6;
}

/* Footer */
.footer {
    background: var(--primary-color);
    color: white;
    padding: 2rem 0;
    margin-top: 2rem;
}

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

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

/* Buttons */
.btn-primary {
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: #2980b9;
    border-color: #2980b9;
    transform: translateY(-2px);
}

.btn-outline-light {
    border-width: 2px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-outline-light:hover {
    transform: translateY(-2px);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-section {
        height: auto;
        min-height: 70vh;
    }

    .hero-content {
        padding: 6rem 0 1.5rem 0;
    }

    .hero-section h1 {
        font-size: 2.5rem;
    }

    .hero-section h2 {
        font-size: 1.2rem;
    }

    .timeline {
        margin-left: 28px;
    }
    .timeline-item {
        flex-direction: column;
        align-items: flex-start;
        min-height: 0;
    }
    .timeline-marker {
        margin-bottom: 0.5rem;
        margin-right: 0;
        left: -10px;
        align-self: flex-start;
        margin-top: 0.3rem;
    }
    .timeline-item .date {
        width: 100%;
        margin-right: 0;
        margin-bottom: 0.5rem;
        text-align: left;
        padding-left: 20px;
        margin-top: -2.2rem;
    }
    .timeline-item .content {
        padding-left: 20px;
    }

    .program-item {
        flex-direction: column;
    }

    .program-item .time {
        width: 100%;
        margin-bottom: 0.5rem;
        flex-direction: row;
        justify-content: center;
        gap: 10px;
        align-items: center;
    }

    .program-item .time-separator {
        margin: 0 5px;
        transform: rotate(90deg);
    }

    .sponsor-logo {
        max-width: 250px;
    }
    
    .sponsor-logo img {
        max-height: 60px;
    }
    
    .sponsor-description {
        font-size: 0.9rem;
    }
    .image-comparison {
        height: 100vh;       
        min-height: 400px;    
      }

    /* Remove conflicting rules for image comparison
    .comparison-wrapper {
        height: 250px;
    }

    .image-comparison {
        height: 50vh;
    }
    */
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section-padding {
    animation: fadeIn 1s ease-out;
}

/* Image Comparison Slider */
.image-comparison {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    height: 100%;
    margin: 0;
    overflow: hidden;
    z-index: 1;
    /* min-height: 1000000px;   */
}


.comparison-wrapper {
    position: relative;
    width: 100%;
    height: 100%;
    /* height: auto; 💡关键2：只撑宽度，高度自适应 */
    /* transform: translate(-50%, -50%); 💡关键3：居中并允许裁切上下部分 */
    /* aspect-ratio: 16 / 9; */
    /* max-height: 800px; */
    overflow: hidden;
    background: rgba(0, 0, 0, 0.2);
}

.comparison-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    background: rgba(0, 0, 0, 0.1);
}

.visible-image {
    z-index: 1;
}

.thermal-image {
    z-index: 2;
    clip-path: polygon(50% 0, 100% 0, 100% 100%, 50% 100%);
}

.handle-line {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 200%;
    height: 2px;
    background: rgba(255, 255, 255, 0.8);
    transform: translate(-50%, -50%);
    z-index: 5;
}

.comparison-handle {
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 200%;
    height: 80px;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0));
    cursor: ns-resize;
    transform: translateX(-50%);
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: center;
}

.handle-circle {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 48px;
    height: 48px;
    background: white;
    border-radius: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
    transition: transform 0.2s ease;
    z-index: 11;
}

.handle-circle:hover {
    transform: translate(-50%, -50%) scale(1.1);
}

.handle-circle i {
    color: var(--primary-color);
    font-size: 1rem;
    margin: 0 2px;
}

.comparison-labels {
    position: absolute;
    bottom: 100px;
    width: 100%;
    display: flex;
    justify-content: space-between;
    padding: 0 20px;
    color: white;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
    font-weight: 500;
    z-index: 3;
}

.label-visible, .label-thermal {
    background: rgba(0, 0, 0, 0.6);
    padding: 6px 16px;
    border-radius: 4px;
    backdrop-filter: blur(4px);
    font-size: 0.95rem;
    letter-spacing: 0.5px;
}

@media (max-width: 768px) {
    /* Remove conflicting rule for comparison-wrapper
    .comparison-wrapper {
        height: 250px;
    }
    */
    
    .comparison-handle {
        height: 60px;
    }
    
    .handle-circle {
        width: 40px;
        height: 40px;
    }
    
    .handle-circle i {
        font-size: 0.8rem;
    }
    
    .comparison-labels {
        bottom: 80px;
        font-size: 0.85rem;
        padding: 0 15px;
    }
    
    .label-visible, .label-thermal {
        padding: 4px 12px;
    }
} 

  .chair-list {
    max-width: 350px;    
    margin: 0 auto;      
    padding-left: 0;     
    list-style: none;    
  }
  .chair-list li {
    position: relative;
    padding-left: 1.2em; 
    text-align: left;    
  }
  .chair-list a {
    text-decoration: none;
  }
 
  .chair-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0.1em;           
    font-size: 1em;
    line-height: 1;
  }
  .chair-list_TPC {
    max-width: 470px;    
    margin: 0 auto;      
    padding-left: 0;     
    list-style: none;    
  }
  .chair-list_TPC li {
    position: relative;
    padding-left: 1.2em; 
    text-align: left;    
  }
  .chair-list_TPC a {
    text-decoration: none;
    padding-left: 1.2em;
  }
 
  .chair-list_TPC li::before {
    content: "•";
    position: absolute;
    left: 0;
    padding-left: 1.2em;
    top: 0.1em;           
    font-size: 1em;
    line-height: 1;
  }

/* 鼠标悬停时，名字变色 */
a.speaker-name:hover {
    color: red; /* Bootstrap primary 蓝色 */
    text-decoration: underline;
    cursor: pointer;
}

/* 鼠标悬停时，图片微放大并加阴影 */
a.speaker-photo img {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

a.speaker-photo:hover img {
    transform: scale(1.05);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
    cursor: pointer;
}