/* 数联科技 AI舞蹈/健身操视频生成平台 - 主样式 */
/* 作者：马靖昱 */

/* ========== CSS 变量 ========== */
:root {
    --bg-primary: #0a0f14;
    --bg-secondary: #0f1419;
    --bg-card: #151c24;
    --bg-card-hover: #1a232d;
    --bg-sheet: #1e2833;
    
    --text-primary: #ffffff;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --accent: #f97316;
    --accent-light: #fb923c;
    --accent-dark: #ea580c;
    --accent-glow: rgba(249, 115, 22, 0.3);
    
    --border: rgba(255, 255, 255, 0.08);
    --border-accent: rgba(249, 115, 22, 0.3);
    
    --gradient-accent: linear-gradient(135deg, #f97316 0%, #fb923c 100%);
    --gradient-bg: linear-gradient(180deg, #0a0f14 0%, #0f1419 100%);
}

/* ========== 基础重置 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ========== 背景动效 ========== */
.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse at 20% 20%, rgba(249, 115, 22, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(251, 146, 60, 0.05) 0%, transparent 50%),
        var(--gradient-bg);
    pointer-events: none;
    z-index: -2;
}

.bg-grid {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    pointer-events: none;
    z-index: -1;
}

/* ========== 导航栏 ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 72px;
    background: rgba(10, 15, 20, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 48px;
    z-index: 1000;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand-icon {
    font-size: 28px;
}

.brand-text {
    font-size: 20px;
    font-weight: 700;
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s;
}

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

.nav-demo-btn {
    background: var(--gradient-accent);
    color: #000 !important;
    padding: 10px 20px;
    border-radius: 10px;
    font-weight: 600;
}

.nav-demo-btn.training {
    background: linear-gradient(135deg, #22c55e 0%, #4ade80 100%);
}

.nav-demo-btn:hover {
    opacity: 0.9;
}

/* ========== Hero 区域 ========== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 48px 80px;
}

.hero-container {
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.hero-content {
    max-width: 640px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(249, 115, 22, 0.1);
    border: 1px solid var(--border-accent);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 13px;
    color: var(--accent);
    margin-bottom: 24px;
}

.title-main {
    font-size: 48px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 12px;
}

.title-gradient {
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.title-sub {
    font-size: 36px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 24px;
}

.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 32px;
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-bottom: 40px;
    padding: 24px;
    background: var(--bg-card);
    border-radius: 16px;
    border: 1px solid var(--border);
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 32px;
    font-weight: 700;
    color: var(--accent);
    display: block;
}

.stat-label {
    font-size: 13px;
    color: var(--text-muted);
}

.hero-actions {
    display: flex;
    gap: 16px;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--gradient-accent);
    color: #000;
    padding: 16px 32px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px var(--accent-glow);
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: transparent;
    color: var(--text-primary);
    padding: 16px 32px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    border: 1px solid var(--border);
    transition: all 0.3s;
    cursor: pointer;
}

.btn-secondary:hover {
    border-color: var(--accent);
    background: rgba(249, 115, 22, 0.1);
}

/* Hero 视觉区域 */
.hero-visual {
    position: relative;
}

.visual-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 32px;
    position: relative;
    overflow: hidden;
}

.visual-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
    opacity: 0.3;
    animation: pulse 4s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.3; }
    50% { transform: scale(1.1); opacity: 0.5; }
}

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

.visual-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
}

.visual-icon {
    width: 48px;
    height: 48px;
    background: var(--gradient-accent);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.visual-title {
    font-size: 18px;
    font-weight: 600;
}

.visual-subtitle {
    font-size: 13px;
    color: var(--text-muted);
}

.visual-demo {
    background: var(--bg-secondary);
    border-radius: 16px;
    padding: 20px;
    margin-bottom: 20px;
}

.demo-input {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 16px;
}

.demo-input-label {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 8px;
    display: block;
}

.demo-input-text {
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.6;
}

.demo-output {
    display: flex;
    gap: 12px;
}

.demo-output-item {
    flex: 1;
    background: var(--bg-card);
    border-radius: 12px;
    padding: 16px;
    text-align: center;
}

.output-icon {
    font-size: 32px;
    margin-bottom: 8px;
}

.output-label {
    font-size: 12px;
    color: var(--text-muted);
}

.visual-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
}

.feature-tag {
    background: rgba(249, 115, 22, 0.1);
    border: 1px solid var(--border-accent);
    border-radius: 8px;
    padding: 10px;
    text-align: center;
    font-size: 12px;
    color: var(--accent);
}

/* ========== 方案对比区域 ========== */
.comparison-section {
    padding: 100px 48px;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-header p {
    font-size: 18px;
    color: var(--text-secondary);
}

.comparison-grid {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
}

.plan-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 40px;
    transition: all 0.3s;
}

.plan-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.plan-card.optimized {
    border-color: var(--border-accent);
    background: linear-gradient(135deg, rgba(249, 115, 22, 0.05) 0%, var(--bg-card) 100%);
}

.plan-badge {
    display: inline-block;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 20px;
}

.plan-card.original .plan-badge {
    background: rgba(100, 116, 139, 0.2);
    color: var(--text-secondary);
}

.plan-card.optimized .plan-badge {
    background: rgba(249, 115, 22, 0.2);
    color: var(--accent);
}

.plan-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 12px;
}

.plan-desc {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.7;
}

.plan-features {
    list-style: none;
    margin-bottom: 32px;
}

.plan-features li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
    font-size: 14px;
    color: var(--text-secondary);
}

.plan-features li:last-child {
    border-bottom: none;
}

.plan-features li::before {
    content: '✓';
    color: var(--accent);
    font-weight: bold;
}

.plan-btn {
    display: block;
    width: 100%;
    text-align: center;
    padding: 16px;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s;
}

.plan-card.original .plan-btn {
    background: var(--bg-sheet);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.plan-card.original .plan-btn:hover {
    background: var(--bg-card-hover);
}

.plan-card.optimized .plan-btn {
    background: var(--gradient-accent);
    color: #000;
}

.plan-card.optimized .plan-btn:hover {
    opacity: 0.9;
}

/* ========== 文档网格 ========== */
.docs-section {
    padding: 100px 48px;
}

.docs-grid {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.doc-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 24px;
    display: flex;
    align-items: center;
    gap: 16px;
    transition: all 0.3s;
    cursor: pointer;
}

.doc-card:hover {
    transform: translateY(-2px);
    border-color: var(--border-accent);
    background: var(--bg-card-hover);
}

.doc-icon {
    font-size: 32px;
}

.doc-info h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 4px;
}

.doc-info p {
    font-size: 12px;
    color: var(--text-muted);
}

.doc-arrow {
    margin-left: auto;
    color: var(--text-muted);
    font-size: 18px;
}

/* ========== Demo 区域 ========== */
.demo-section {
    padding: 100px 48px;
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.demo-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

/* 双Demo布局 */
.demo-dual-container {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.demo-card-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 40px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    align-items: center;
    transition: all 0.3s;
}

.demo-card-wrapper:hover {
    border-color: var(--border-accent);
    box-shadow: 0 20px 60px rgba(249, 115, 22, 0.1);
}

.demo-card-wrapper.training:hover {
    border-color: rgba(34, 197, 94, 0.3);
    box-shadow: 0 20px 60px rgba(34, 197, 94, 0.1);
}

.demo-card-wrapper .demo-text h2 {
    font-size: 24px;
    margin-bottom: 16px;
}

.demo-card-wrapper .demo-text p {
    font-size: 14px;
    margin-bottom: 20px;
}

.demo-card-wrapper .demo-features li {
    padding: 8px 0;
    font-size: 13px;
}

.demo-card-wrapper .btn-demo {
    padding: 14px 28px;
    font-size: 14px;
}

.demo-card-wrapper .btn-demo.training {
    background: linear-gradient(135deg, #22c55e 0%, #4ade80 100%);
}

.demo-card-wrapper .demo-frame {
    display: block;
    text-decoration: none;
    position: relative;
}

.demo-card-wrapper .demo-frame.training .demo-screen {
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.1) 0%, var(--bg-secondary) 100%);
}

.demo-card-wrapper .demo-screen {
    aspect-ratio: 4/3;
    font-size: 48px;
}

.demo-card-wrapper .demo-screen::after {
    display: none;
}

.demo-hint {
    display: block;
    text-align: center;
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 12px;
}

@media (max-width: 1200px) {
    .demo-dual-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .demo-card-wrapper {
        grid-template-columns: 1fr;
        padding: 24px;
    }
    
    .demo-card-wrapper .demo-preview {
        order: -1;
    }
}

.demo-text h2 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 20px;
}

.demo-text p {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 32px;
    line-height: 1.8;
}

.demo-features {
    list-style: none;
    margin-bottom: 32px;
}

.demo-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 0;
    font-size: 15px;
    color: var(--text-secondary);
}

.demo-features li::before {
    content: '🎯';
}

.btn-demo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: var(--gradient-accent);
    color: #000;
    padding: 18px 36px;
    border-radius: 14px;
    font-size: 17px;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-demo:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px var(--accent-glow);
}

.demo-preview {
    position: relative;
}

.demo-frame {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 24px;
    box-shadow: 0 40px 100px rgba(0,0,0,0.4);
}

.demo-screen {
    background: var(--bg-secondary);
    border-radius: 16px;
    aspect-ratio: 16/10;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 64px;
    position: relative;
    overflow: hidden;
}

.demo-screen::after {
    content: '点击体验完整Demo';
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 14px;
    color: var(--text-muted);
}

/* ========== Footer ========== */
.footer {
    padding: 60px 48px 30px;
    border-top: 1px solid var(--border);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
}

.footer-brand {
    font-size: 18px;
    font-weight: 600;
}

.footer-info p {
    font-size: 14px;
    color: var(--text-secondary);
}

.footer-info strong {
    color: var(--accent);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

.footer-bottom p {
    font-size: 13px;
    color: var(--text-muted);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .hero-visual {
        order: -1;
    }
    
    .comparison-grid {
        grid-template-columns: 1fr;
    }
    
    .demo-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .navbar {
        padding: 0 20px;
    }
    
    .nav-links a:not(.nav-demo-btn) {
        display: none;
    }
    
    .hero {
        padding: 100px 20px 60px;
    }
    
    .title-main {
        font-size: 32px;
    }
    
    .title-sub {
        font-size: 24px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .comparison-section,
    .docs-section,
    .demo-section {
        padding: 60px 20px;
    }
    
    .section-header h2 {
        font-size: 28px;
    }
    
    .footer {
        padding: 40px 20px 20px;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
}

/* ========== 移动端 H5 专属样式 ========== */
.mobile-banner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 44px;
    background: linear-gradient(135deg, #3d2a0d 0%, #1e1a14 100%);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    z-index: 1001;
    border-bottom: 1px solid var(--border-accent);
}

.mobile-banner span {
    color: var(--accent);
    font-size: 13px;
    font-weight: 500;
}

.mobile-demo-btn {
    background: var(--gradient-accent);
    color: #000;
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
    text-decoration: none;
}

.mobile-device .navbar {
    top: 44px;
    height: 56px;
    padding: 0 16px;
}

.mobile-device .hero {
    padding: 130px 20px 40px;
    min-height: auto;
}