/* ===== 重置和基础样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 主色调 */
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #8b5cf6;
    
    /* 辅助色调 */
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --success-color: #10b981;
    
    /* 中性色调 */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --gradient-card: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* 边框半径 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    
    /* 动画 */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', 'Poppins', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-primary);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    z-index: 1000;
    transition: var(--transition-normal);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 1.25rem;
    color: var(--text-primary);
    text-decoration: none;
}

.logo-icon {
    font-size: 1.5rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-fast);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 50%;
    background: var(--gradient-primary);
    transition: var(--transition-fast);
    transform: translateX(-50%);
}

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

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: var(--transition-fast);
    border-radius: var(--radius-full);
}

/* ===== 英雄区域 ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: var(--gradient-hero);
    position: relative;
    overflow: hidden;
}

.hero::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"><circle cx="50" cy="50" r="2" fill="rgba(255,255,255,0.1)"/></svg>') repeat;
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    min-height: 100vh;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: white;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.gradient-text {
    background: linear-gradient(45deg, #fff, #f0f9ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.9;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 2rem;
    border-radius: var(--radius-full);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition-normal);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-primary:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.125rem;
}

.hero-stats {
    display: flex;
    gap: 2rem;
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.stat-number {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    opacity: 0.8;
}

/* ===== 英雄区域可视化 ===== */
.hero-visual {
    position: relative;
    height: 500px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.floating-circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    animation: pulse 2s ease-in-out infinite;
    animation-delay: var(--delay, 0s);
}

.main-circle {
    width: 200px;
    height: 200px;
    font-size: 4rem;
}

.feature-circle {
    width: 80px;
    height: 80px;
    font-size: 2rem;
}

.feature-circle:nth-child(2) { top: 20%; left: 20%; }
.feature-circle:nth-child(3) { top: 20%; right: 20%; }
.feature-circle:nth-child(4) { bottom: 20%; left: 20%; }
.feature-circle:nth-child(5) { bottom: 20%; right: 20%; }

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

/* ===== 功能特性区域 ===== */
.features {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--gradient-card);
    padding: 2rem;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: var(--transition-normal);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

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

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== 演示区域 ===== */
.demo {
    padding: 6rem 0;
    background: var(--bg-primary);
}

.demo-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.demo-image {
    position: relative;
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.demo-image img {
    width: 100%;
    height: auto;
    display: block;
}

.demo-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition-normal);
}

.demo-image:hover .demo-overlay {
    opacity: 1;
}

.demo-play-btn {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.9);
    border: none;
    font-size: 2rem;
    color: var(--primary-color);
    cursor: pointer;
    transition: var(--transition-normal);
}

.demo-play-btn:hover {
    transform: scale(1.1);
    background: white;
}

.demo-info h3 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.demo-info p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.tech-specs {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
}

.tech-specs h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.tech-specs ul {
    list-style: none;
}

.tech-specs li {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.tech-specs strong {
    color: var(--text-primary);
}

/* ===== 下载区域 ===== */
.download {
    padding: 6rem 0;
    background: var(--gradient-primary);
}

.download-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-xl);
    padding: 4rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.download-content {
    color: white;
}

.download-content h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.download-content > p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.download-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.download-info {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.info-item {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.info-label {
    opacity: 0.8;
}

.info-value {
    font-weight: 500;
}

.download-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.download-illustration {
    position: relative;
}

.download-circle {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    animation: rotate 20s linear infinite;
}

.download-icon {
    font-size: 6rem;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* ===== 页脚 ===== */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    margin-bottom: 2rem;
}

.footer-brand p {
    margin-top: 0.5rem;
    opacity: 0.8;
}

.footer-logo {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    font-weight: 600;
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    opacity: 0.8;
}

/* ===== 响应式设计 ===== */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: var(--transition-normal);
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        padding: 2rem 1rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .demo-container {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .download-card {
        grid-template-columns: 1fr;
        padding: 2rem;
        text-align: center;
    }
    
    .download-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-visual {
        height: 300px;
    }
    
    .main-circle {
        width: 150px;
        height: 150px;
        font-size: 3rem;
    }
    
    .feature-circle {
        width: 60px;
        height: 60px;
        font-size: 1.5rem;
    }
}