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

:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --accent-primary: #01529e;
    --accent-secondary: #fdb902;
    --accent-gradient: linear-gradient(135deg, rgb(1, 82, 158), rgb(232, 46, 130));
    --author-gradient: linear-gradient(135deg, rgb(253, 185, 2), rgb(253, 185, 2));
    --blue-skies: linear-gradient(to right, rgb(86, 204, 242), rgb(47, 128, 237));
    --roseanna: linear-gradient(to right, rgb(255, 175, 189), rgb(255, 195, 160));
    --jshine: linear-gradient(to right, rgb(1, 82, 158), rgb(232, 46, 130), rgb(253, 185, 2));
    --piggy-pink: linear-gradient(to right, rgb(238, 156, 167), rgb(255, 221, 225));
    --azur-lane: linear-gradient(to right, rgb(127, 127, 213), rgb(134, 168, 231), rgb(145, 234, 228));
    --magic: linear-gradient(to right, rgb(89, 193, 115), rgb(161, 127, 224), rgb(93, 38, 193));
    --moon-purple: linear-gradient(to right, rgb(78, 84, 200), rgb(143, 148, 251));
    --slight-ocean: linear-gradient(to right, rgb(168, 192, 255), rgb(63, 43, 150));
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Fix for anchor links with fixed navbar */
section {
    scroll-margin-top: 90px; /* navbar height (70px) + extra padding (20px) */
}

.container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 0 60px;
}

.gradient-icon {
  background: linear-gradient(45deg, #e82e82, #01529e);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent; /* for Chrome/Safari */
          background-clip: text;        /* Firefox */
          color: transparent;
}

/* Theme toggle removed - only light mode supported */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 999;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo h2 {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

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

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

/* Banner */
.banner {
    background: var(--jshine);
    color: white;
    padding: 100px 0 60px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="white" opacity="0.1"/><circle cx="75" cy="75" r="1" fill="white" opacity="0.1"/><circle cx="50" cy="10" r="0.5" fill="white" opacity="0.1"/><circle cx="10" cy="60" r="0.5" fill="white" opacity="0.1"/><circle cx="90" cy="40" r="0.5" fill="white" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
}

.banner-content {
    position: relative;
    z-index: 1;
}

.banner-title {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 10px;
    text-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

.banner-subtitle {
    font-size: 2rem;
    font-weight: 400;
    margin-bottom: 30px;
    opacity: 0.9;
}

.authors {
    font-size: 1.1rem;
    margin-bottom: 40px;
    /*opacity: 0.9;*/
}

.authors a {
    color: white;
    text-decoration: none;
    transition: opacity 0.3s ease;
    /* ensure pseudo-element positions/sizes correctly and behaves like nav-links */
    position: relative;
    display: inline-block;
}

/* hovering underline bar for author links (matches nav-links behavior) */
.authors a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--author-gradient);
    transition: width 0.3s ease;
}

.authors a:hover {
    opacity: 0.8;
    color: white; /* keep color stable if desired */
}

.authors a:hover::after {
    width: 100%;
}

.banner-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.link-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    text-decoration: none;
    padding: 12px 24px;
    border-radius: 50px;
    font-weight: 500;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.link-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.main-demo {
    padding: 40px 0;
    background: var(--bg-secondary);
}

.demo-video-container {
    max-width: 1200px;
    margin: 0 auto;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    position: relative;
    background: var(--bg-tertiary);
}

.main-video {
    width: 100%;
    height: auto;
    display: block;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.main-video.loaded {
    opacity: 1;
}

/* Video loading indicator */
.video-loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 10;
    transition: opacity 0.3s ease;
}

.video-loader.hidden {
    opacity: 0;
    pointer-events: none;
}

.loader-spinner {
    width: 60px;
    height: 60px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loader-text {
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    margin-bottom: 15px;
}

.loader-progress {
    width: 200px;
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
    margin: 0 auto;
}

.progress-bar {
    height: 100%;
    background: var(--accent-gradient);
    width: 0%;
    transition: width 0.3s ease;
    border-radius: 3px;
}

.tldr-content {
    background: var(--bg-secondary);
    padding: 20px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    text-align: center;
    max-width: 1200px;
    margin: 0 auto 30px auto;
}

.tldr-content p {
    font-size: 1.3rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin: 0;
}

.tldr-content i {
    color: var(--accent-primary);
    margin-right: 8px;
}

.tldr-content strong {
    color: var(--text-primary);
}

.abstract {
    padding: 40px 0;
    background: var(--bg-primary);
}

.abstract-content {
    background: var(--bg-secondary);
    padding: 20px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    text-align: center;
    max-width: 1200px;
    margin: 0 auto 30px auto;
}

.abstract-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--accent-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.abstract-content p {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-secondary);
}

.benchmark-chart {
    text-align: center;
    max-width: 1200px;
    margin: 0 auto;
}

.benchmark-image {
    max-width: 100%;
    height: auto;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
    aspect-ratio: 2.5 / 1;
    object-fit: cover;
}

.interactive-results {
    padding: 40px 0;
    background: var(--bg-secondary);
}

/* Main display area for interactive examples */
.main-display-container {
    width: 100%;
    max-width: 768px;
    margin: 0 auto 30px;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    background: var(--bg-tertiary);
    position: relative;
    aspect-ratio: 16 / 9;
}

.main-iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.main-iframe.loaded {
    opacity: 1;
}

/* Iframe loading indicator */
.iframe-loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 10;
    transition: opacity 0.3s ease;
}

.iframe-loader.hidden {
    opacity: 0;
    pointer-events: none;
}

/* Thumbnail gallery */
.thumbnail-gallery {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 15px;
    max-width: 1200px;
    margin: 0 auto;
}

.thumbnail-item {
    position: relative;
    border-radius: 10px;
    overflow: hidden;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-md);
    border: 2px solid transparent;
    background: var(--bg-primary);
    user-select: none;
}

.thumbnail-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.thumbnail-item:active {
    transform: translateY(-1px) scale(0.98);
}

.thumbnail-item.active {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.thumbnail-item.loading {
    opacity: 0.6;
    pointer-events: none;
}

.thumbnail-item img {
    width: 100%;
    height: 110px;
    object-fit: cover;
    display: block;
    transition: transform 0.3s ease;
}

.thumbnail-item:hover img {
    transform: scale(1.05);
}

.thumbnail-label {
    padding: 8px;
    text-align: center;
    font-weight: 600;
    color: var(--text-primary);
    background: var(--bg-primary);
    font-size: 0.8rem;
}

.thumbnail-item.active .thumbnail-label {
    color: var(--accent-primary);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 60px;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Reduce spacing for citation section title */
.citation .section-title {
    margin-bottom: 20px;
}

.interactive-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 40px;
}

.interactive-item {
    background: var(--bg-primary);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.interactive-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.interactive-video-wrapper {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 */
    height: 0;
    overflow: hidden;
}

.interactive-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.interactive-info {
    padding: 20px;
}

.interactive-info h4 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.interactive-info p {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.applications {
    padding: 40px 0;
    background: var(--bg-secondary);
}

.applications-carousel {
    position: relative;
}

.carousel-container {
    display: flex;
    align-items: center;
    gap: 20px;
}

.carousel-btn {
    background: var(--accent-gradient);
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    color: white;
    font-size: 18px;
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.carousel-btn:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-lg);
}

.carousel-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.carousel-content {
    flex: 1;
    position: relative;
    overflow: hidden;
    border-radius: 20px;
    background: var(--bg-primary);
    box-shadow: var(--shadow-lg);
}

.application-slide,
.analysis-slide {
    display: none;
    padding: 40px;
}

.application-slide.active,
.analysis-slide.active {
    display: block;
}

.application-video,
.analysis-video-wrapper {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 15px;
    margin-bottom: 30px;
    background: var(--bg-tertiary);
}

.app-video,
.analysis-video-player {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.app-video.loaded,
.analysis-video-player.loaded {
    opacity: 1;
}

/* Video loaders for app and analysis sections */
.app-video-loader,
.analysis-video-loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 10;
    transition: opacity 0.3s ease;
}

.app-video-loader.hidden,
.analysis-video-loader.hidden {
    opacity: 0;
    pointer-events: none;
}

.application-info h3,
.analysis-info h3 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.application-info p,
.analysis-info p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.carousel-indicators {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 30px;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--text-muted);
    cursor: pointer;
    transition: all 0.3s ease;
}

.indicator.active {
    background: var(--accent-primary);
    transform: scale(1.2);
}

.analysis {
    padding: 40px 0;
    background: var(--bg-primary);
}

.citation {
    padding: 40px 0;
    background: var(--bg-primary);
}

.citation-box {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: 15px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    max-width: 800px;
    margin: 0 auto;
    position: relative; /* enable absolute button positioning */
}

.citation-box pre {
    background: var(--bg-tertiary);
    padding: 20px;
    border-radius: 10px;
    overflow-x: auto;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    color: var(--text-primary);
}

/* Copy button styles */
.copy-code-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 10px;
    font-size: 0.7rem;
    font-weight: 500;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease;
    line-height: 1;
}

.copy-code-btn i {
    font-size: 0.85rem;
}

.copy-code-btn:hover {
    background: var(--accent-primary);
    color: #fff;
}

.copy-code-btn.copied {
    background: var(--accent-primary);
    color: #fff;
}

.copy-code-btn.copied i {
    color: #fff;
}

.footer {
    background: var(--bg-tertiary);
    padding: 40px 0;
    text-align: center;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
}

@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }
    
    .banner {
        padding: 80px 0 40px;
    }
    
    .banner-title {
        font-size: 2.5rem;
    }
    
    .banner-subtitle {
        font-size: 1.2rem;
    }
    
    .banner-links {
        flex-direction: column;
        align-items: center;
    }
    
    .nav-links {
        display: none;
    }
    
    .main-demo,
    .abstract,
    .interactive-results,
    .applications,
    .analysis,
    .citation {
        padding: 30px 0;
    }
    
    .tldr-content,
    .abstract-content {
        max-width: 100%;
        padding: 20px;
    }
    
    .tldr-content p {
        font-size: 1.1rem;
    }
    
    .demo-video-container {
        max-width: 100%;
    }
    
    .interactive-grid {
        grid-template-columns: 1fr;
    }
    
    .carousel-container {
        flex-direction: column;
    }
    
    .carousel-btn {
        position: absolute;
        top: 50%;
        transform: translateY(-50%);
    }
    
    .prev-btn {
        left: 10px;
    }
    
    .next-btn {
        right: 10px;
    }
    
    /* Responsive thumbnail gallery */
    .thumbnail-gallery {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }
    
    .thumbnail-item img {
        height: 70px;
    }
    
    .thumbnail-label {
        padding: 6px;
        font-size: 0.7rem;
    }
    
    .main-display-container {
        aspect-ratio: 4 / 3;
    }
}

.video-placeholder {
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    font-size: 1.2rem;
    font-weight: 500;
    border: 2px dashed var(--border-color);
    border-radius: 15px;
    min-height: 200px;
}

.video-placeholder i {
    font-size: 3rem;
    margin-bottom: 10px;
    display: block;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-secondary);
}