/* ============================================
   A3D Project Website - Stylesheet
   Inspired by DexGarmentLab & Nerfies
   ============================================ */

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --accent: #06b6d4;
    --accent-glow: rgba(6, 182, 212, 0.3);
    --bg-dark: #0f172a;
    --bg-section: #1e293b;
    --bg-card: #334155;
    --bg-alt: #f8fafc;
    --bg-white: #ffffff;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-dark: #1e293b;
    --text-muted: #64748b;
    --gradient-hero: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #0f172a 100%);
    --gradient-accent: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
    --gradient-card: linear-gradient(145deg, rgba(51, 65, 85, 0.8), rgba(30, 41, 59, 0.9));
    --container-max: 1200px;
    --section-padding: 6rem 0;
    --font-display: 'Crimson Pro', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 40px var(--accent-glow);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: var(--font-body); background: var(--bg-white); color: var(--text-dark); line-height: 1.7; overflow-x: hidden; }
.container { max-width: var(--container-max); margin: 0 auto; padding: 0 2rem; }

/* Navigation */
.navbar { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: rgba(15, 23, 42, 0.95); backdrop-filter: blur(10px); border-bottom: 1px solid rgba(255, 255, 255, 0.1); transition: var(--transition-normal); }
.nav-container { max-width: var(--container-max); margin: 0 auto; padding: 1rem 2rem; display: flex; justify-content: space-between; align-items: center; }
.nav-logo { font-family: var(--font-display); font-size: 1.8rem; font-weight: 700; color: var(--text-primary); text-decoration: none; background: var(--gradient-accent); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.nav-links { display: flex; gap: 2rem; list-style: none; }
.nav-links a { color: var(--text-secondary); text-decoration: none; font-size: 0.95rem; font-weight: 500; transition: var(--transition-fast); position: relative; }
.nav-links a::after { content: ''; position: absolute; bottom: -4px; left: 0; width: 0; height: 2px; background: var(--gradient-accent); transition: var(--transition-normal); }
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }

/* Hero Section */
.hero { min-height: 100vh; background: var(--gradient-hero); display: flex; align-items: center; justify-content: center; text-align: center; padding: 8rem 2rem 4rem; position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0; background-image: radial-gradient(circle at 20% 80%, rgba(6, 182, 212, 0.15) 0%, transparent 50%), radial-gradient(circle at 80% 20%, rgba(37, 99, 235, 0.15) 0%, transparent 50%), radial-gradient(circle at 40% 40%, rgba(6, 182, 212, 0.1) 0%, transparent 30%); animation: float 20s ease-in-out infinite; }
@keyframes float { 0%, 100% { transform: translateY(0) rotate(0deg); } 50% { transform: translateY(-20px) rotate(1deg); } }
.hero-content { position: relative; z-index: 1; max-width: 900px; }
.venue-badge { display: inline-flex; align-items: center; gap: 0.6rem; background: rgba(6, 182, 212, 0.2); border: 2px solid rgba(6, 182, 212, 0.5); padding: 0.75rem 1.75rem; border-radius: 50px; margin-bottom: 2rem; animation: fadeInUp 0.8s ease; box-shadow: 0 0 20px rgba(6, 182, 212, 0.3); }
.venue-badge .venue-icon { font-size: 1.5rem; }
.venue-badge span { color: var(--accent); font-weight: 700; font-size: 1.2rem; letter-spacing: 0.5px; }
.title { font-family: var(--font-display); font-size: clamp(2.5rem, 6vw, 4rem); font-weight: 600; color: var(--text-primary); margin-bottom: 1rem; line-height: 1.2; animation: fadeInUp 0.8s ease 0.1s both; }
.title-highlight { background: var(--gradient-accent); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.title-letter { background: var(--gradient-accent); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; font-weight: 700; }
.subtitle { font-size: 1.25rem; color: var(--text-secondary); margin-bottom: 2.5rem; animation: fadeInUp 0.8s ease 0.2s both; }
.authors-container { margin-bottom: 1rem; animation: fadeInUp 0.8s ease 0.3s both; }
.authors-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 1.5rem 2rem; margin-bottom: 0.75rem; }
.author { color: var(--text-primary); }
.author-name { font-weight: 500; transition: var(--transition-fast); cursor: pointer; color: inherit; text-decoration: none; }
.author-name:hover { color: var(--accent); }
a.author-name { color: var(--text-primary); }
a.author-name:hover { color: var(--accent); }
.author sup { font-size: 0.85rem; font-weight: 700; margin-left: 2px; }
.sup-equal { color: #f59e0b; text-shadow: 0 0 8px rgba(245, 158, 11, 0.5); }
.sup-corresponding { color: #10b981; text-shadow: 0 0 8px rgba(16, 185, 129, 0.5); }
.affiliations { color: var(--text-secondary); font-size: 0.95rem; margin-bottom: 2.5rem; animation: fadeInUp 0.8s ease 0.4s both; }
.equal-contrib { font-size: 0.85rem; color: var(--text-muted); margin-top: 0.5rem; }
.action-buttons { display: flex; flex-wrap: wrap; justify-content: center; gap: 1rem; animation: fadeInUp 0.8s ease 0.5s both; }
.btn { display: inline-flex; align-items: center; gap: 0.6rem; padding: 0.875rem 1.75rem; border-radius: var(--radius-md); font-weight: 600; font-size: 0.95rem; text-decoration: none; transition: var(--transition-normal); cursor: pointer; border: none; }
.btn-primary { background: var(--gradient-accent); color: white; box-shadow: 0 4px 20px rgba(37, 99, 235, 0.3); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(37, 99, 235, 0.4); }
.btn-secondary { background: rgba(255, 255, 255, 0.1); color: var(--text-primary); border: 1px solid rgba(255, 255, 255, 0.2); }
.btn-secondary:hover { background: rgba(255, 255, 255, 0.15); border-color: var(--accent); transform: translateY(-2px); }

/* Teaser Section */
.teaser { background: var(--bg-dark); padding: 2rem 0 4rem; }
.teaser-content { max-width: 960px; margin: 0 auto; padding: 0 1rem; }
.video-wrapper { position: relative; width: 100%; border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-lg), 0 0 60px rgba(6, 182, 212, 0.2); }
.teaser-video { display: block; width: 100%; height: auto; }
.video-placeholder, .image-placeholder { display: block; }
.image-placeholder img { width: 100%; height: auto; border-radius: var(--radius-md); }
.video-placeholder.large { min-height: 400px; }
.image-placeholder.small { aspect-ratio: 4/3; min-height: 250px; }

/* Sections */
.section { padding: var(--section-padding); }
.section-alt { background: var(--bg-alt); }
.section-title { font-family: var(--font-display); font-size: 2.5rem; font-weight: 600; text-align: center; margin-bottom: 3rem; color: var(--text-dark); position: relative; }
.section-title::after { content: ''; display: block; width: 60px; height: 4px; background: var(--gradient-accent); margin: 1rem auto 0; border-radius: 2px; }
.subsection-title { font-size: 1.5rem; font-weight: 600; margin-bottom: 1.5rem; color: var(--text-dark); }
.abstract-content { max-width: 800px; margin: 0 auto; font-size: 1.1rem; text-align: justify; }
.abstract-content p { margin-bottom: 1.5rem; }

/* Tab Container */
.tab-container { margin-top: 2rem; }
.tab-buttons { display: flex; justify-content: center; gap: 1rem; margin-bottom: 2rem; }
.tab-btn { padding: 0.75rem 2rem; background: transparent; border: 2px solid var(--primary); color: var(--primary); border-radius: var(--radius-md); font-weight: 600; cursor: pointer; transition: var(--transition-normal); }
.tab-btn.active, .tab-btn:hover { background: var(--primary); color: white; }
.tab-panel { display: none; animation: fadeIn 0.5s ease; }
.tab-panel.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
@keyframes fadeInUp { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }

/* Overview */
.overview-image { margin-bottom: 2rem; }
.overview-image .image-placeholder { }
.feature-list { list-style: none; max-width: 700px; margin: 0 auto; }
.feature-list li { display: flex; gap: 1rem; margin-bottom: 1.5rem; padding: 1rem; background: white; border-radius: var(--radius-md); box-shadow: var(--shadow-sm); }
.feature-icon { font-size: 1.5rem; flex-shrink: 0; }

/* Method Section */
.method-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 2rem; margin-bottom: 4rem; }
.method-card { background: white; padding: 2rem; border-radius: var(--radius-lg); box-shadow: var(--shadow-md); text-align: center; transition: var(--transition-normal); }
.method-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); }
.method-icon { width: 70px; height: 70px; background: var(--gradient-accent); border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 1.5rem; }
.method-icon i { font-size: 1.75rem; color: white; }
.method-card h3 { font-size: 1.25rem; margin-bottom: 1rem; color: var(--text-dark); }
.method-details { max-width: 900px; margin: 0 auto; }
.method-row { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; align-items: center; }
.method-text h3 { font-size: 1.5rem; margin-bottom: 1rem; color: var(--text-dark); }
.method-figure .image-placeholder { }

/* Results Section */
.results-gallery { margin-bottom: 4rem; }
.video-tabs { display: flex; flex-wrap: wrap; justify-content: center; gap: 0.75rem; margin-bottom: 2rem; }
.video-tab { padding: 0.625rem 1.5rem; background: white; border: 2px solid #e2e8f0; border-radius: var(--radius-sm); font-weight: 500; cursor: pointer; transition: var(--transition-fast); }
.video-tab.active, .video-tab:hover { background: var(--primary); border-color: var(--primary); color: white; }
.video-showcase { max-width: 800px; margin: 0 auto; }
.video-panel { display: none; }
.video-panel.active { display: block; animation: fadeIn 0.5s ease; }
.video-panel .video-placeholder { background: linear-gradient(145deg, #e2e8f0, #cbd5e1); border-color: #94a3b8; color: var(--text-muted); }
.video-panel .video-placeholder i { color: var(--primary); }
.comparison-section { margin-bottom: 4rem; }
.table-wrapper { overflow-x: auto; border-radius: var(--radius-md); box-shadow: var(--shadow-md); }
.results-table { width: 100%; border-collapse: collapse; background: white; }
.results-table th, .results-table td { padding: 1rem 1.5rem; text-align: center; border-bottom: 1px solid #e2e8f0; }
.results-table th { background: var(--bg-dark); color: var(--text-primary); font-weight: 600; }
.results-table tbody tr:hover { background: #f8fafc; }
.results-table tr.highlight { background: rgba(37, 99, 235, 0.08); }
.results-table tr.highlight:hover { background: rgba(37, 99, 235, 0.12); }
.comparison-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }
.comparison-item .image-placeholder { background: linear-gradient(145deg, #e2e8f0, #cbd5e1); border-color: #94a3b8; color: var(--text-muted); aspect-ratio: 1; }

/* Real-World Section */
.realworld-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: 2rem; }
.realworld-card { background: var(--bg-alt); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-md); }
.realworld-video .video-placeholder { border-radius: 0; background: linear-gradient(145deg, #e2e8f0, #cbd5e1); border: none; color: var(--text-muted); }
.realworld-video .video-placeholder i { color: var(--primary); }
.realworld-card h4 { padding: 1.5rem 1.5rem 0.5rem; font-size: 1.1rem; }
.realworld-card p { padding: 0 1.5rem 1.5rem; color: var(--text-muted); }

/* BibTeX */
.bibtex-container { position: relative; max-width: 700px; margin: 0 auto; }
.copy-btn { position: absolute; top: 1rem; right: 1rem; padding: 0.5rem 1rem; background: var(--primary); color: white; border: none; border-radius: var(--radius-sm); cursor: pointer; display: flex; align-items: center; gap: 0.5rem; font-weight: 500; transition: var(--transition-fast); }
.copy-btn:hover { background: var(--primary-dark); }
.bibtex-code { background: var(--bg-dark); color: var(--text-secondary); padding: 2rem; border-radius: var(--radius-md); overflow-x: auto; font-family: 'Monaco', 'Menlo', monospace; font-size: 0.9rem; line-height: 1.8; }

/* Footer */
.footer { background: var(--bg-dark); color: var(--text-secondary); text-align: center; padding: 3rem 2rem; }
.footer a { color: var(--accent); text-decoration: none; }
.footer a:hover { text-decoration: underline; }
.copyright { margin-top: 1rem; font-size: 0.9rem; color: var(--text-muted); }

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .title { font-size: 2rem; }
    .authors { flex-direction: column; gap: 0.5rem; }
    .action-buttons { flex-direction: column; align-items: center; }
    .btn { width: 100%; max-width: 250px; justify-content: center; }
    .method-row { grid-template-columns: 1fr; }
    .comparison-grid { grid-template-columns: repeat(2, 1fr); }
    .section { padding: 4rem 0; }
}

.animate-on-scroll { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease, transform 0.6s ease; }
.animate-on-scroll.visible { opacity: 1; transform: translateY(0); }
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--bg-alt); }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--primary-dark); }