/* 全局样式 */
:root {
    --primary-color: #000000;
    --secondary-color: #666666;
    --text-color: #333333;
    --bg-color: #fafafa;
    --card-bg: #ffffff;
    --border-color: #eeeeee;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.8;
    color: var(--text-color);
    scroll-behavior: smooth;
    background: var(--bg-color);
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 20px;
}

.nav-brand {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: 2.5rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--secondary-color);
    font-weight: 400;
    font-size: 0.95rem;
    transition: color 0.2s;
}

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

/* 英雄区域 */
.hero {
    padding: 60px 20px 40px;
    text-align: center;
    background: var(--bg-color);
}

.hero h1 {
    font-size: 2.2rem;
    margin-bottom: 0.3rem;
    font-weight: 600;
    color: var(--primary-color);
    letter-spacing: -0.5px;
    line-height: 1.3;
}

.conference-badge {
    display: block;
    color: #dc3545;
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.8rem;
}

.hero .subtitle {
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    color: var(--secondary-color);
    font-weight: 400;
}

.authors {
    margin: 1rem 0 0.5rem;
    font-size: 1rem;
    color: var(--text-color);
}

.author {
    margin: 0 0.3rem;
}

.affiliations {
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: var(--secondary-color);
    line-height: 1.5;
}

.buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

.links {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    margin-top: 1.5rem;
    font-size: 1rem;
}

.links a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

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

.links .separator {
    color: var(--secondary-color);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.65rem 1.8rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: all 0.2s;
    border: 1px solid var(--border-color);
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.btn-primary:hover {
    background: #333333;
    border-color: #333333;
    box-shadow: var(--shadow-hover);
}

.btn-secondary {
    background: var(--card-bg);
    color: var(--primary-color);
}

.btn-secondary:hover {
    background: var(--bg-color);
    box-shadow: var(--shadow-hover);
}

/* 章节 */
.section {
    padding: 20px 20px;
    background: var(--bg-color);
}

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

.section h2 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--primary-color);
    font-weight: 600;
    letter-spacing: -0.5px;
}

.section h3 {
    font-size: 1.1rem;
    margin-top: 1.5rem;
    margin-bottom: 0.8rem;
    color: var(--primary-color);
    font-weight: 600;
}

.content {
    max-width: 900px;
    margin: 0 auto;
    background: var(--card-bg);
    padding: 1.8rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.content p {
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 0.8rem;
    color: var(--text-color);
}

.content ul {
    margin: 1.5rem 0;
    padding-left: 2rem;
}

.content li {
    font-size: 1rem;
    margin-bottom: 0.75rem;
    color: var(--text-color);
}

/* 占位符 */
.placeholder-image,
.placeholder-video {
    background: var(--bg-color);
    border-radius: 8px;
    padding: 80px 20px;
    margin: 2rem 0;
    text-align: center;
    color: var(--secondary-color);
    border: 1px dashed var(--border-color);
    font-size: 0.9rem;
}

/* 方法概览 */
.method-overview {
    margin-top: 1rem;
}

/* 结果网格 */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.result-item {
    text-align: center;
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.result-item:hover {
    box-shadow: var(--shadow-hover);
}

.caption {
    margin-top: 1rem;
    font-size: 0.9rem;
    color: var(--secondary-color);
}

/* 视频对比 */
.video-comparison {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin: 1.5rem 0;
}

.video-item {
    text-align: center;
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.video-item:hover {
    box-shadow: var(--shadow-hover);
}

.video-item video {
    width: 100%;
    border-radius: 6px;
    background: #000;
}

.video-item .caption {
    margin-top: 0.8rem;
    font-weight: 500;
}

/* 代码块 */
pre {
    background: var(--bg-color);
    color: var(--text-color);
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
}

code {
    font-family: 'Monaco', 'Menlo', 'Courier New', monospace;
    font-size: 0.85rem;
    line-height: 1.6;
}

/* 页脚 */
.footer {
    background: var(--card-bg);
    color: var(--secondary-color);
    text-align: center;
    padding: 3rem 20px;
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
}

.footer h4 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.acknowledgments {
    margin-bottom: 2rem;
}

.ack-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1rem;
}

.ack-links a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    transition: all 0.2s;
}

.ack-links a:hover {
    background: var(--bg-color);
    box-shadow: var(--shadow-hover);
}

.acknowledgments p a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.acknowledgments p a:hover {
    text-decoration: underline;
}

.citation {
    margin-bottom: 2rem;
}

.citation-box {
    position: relative;
    max-width: 700px;
    margin: 0 auto;
}

.citation-box pre {
    text-align: left;
    font-size: 0.8rem;
    padding-right: 4rem;
}

.copy-btn {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    padding: 0.4rem 0.8rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s;
}

.copy-btn:hover {
    background: #333;
}

.copyright {
    margin-top: 2rem;
    color: var(--secondary-color);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero .subtitle {
        font-size: 1rem;
    }

    .nav-links {
        gap: 1.5rem;
        font-size: 0.9rem;
    }

    .section h2 {
        font-size: 1.6rem;
    }

    .content {
        padding: 2rem 1.5rem;
    }

    .buttons {
        flex-direction: column;
        align-items: stretch;
    }

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

    .video-comparison {
        grid-template-columns: 1fr;
    }
}

/* 动画效果 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section {
    animation: fadeInUp 0.6s ease-out;
}