/* ==================== 快连 - 主样式文件 ==================== */

/* CSS变量定义 */
:root {
    /* 主色调 */
    --primary: #00d4ff;
    --primary-light: #33ddff;
    --primary-dark: #0099cc;
    --secondary: #ff6b6b;
    --accent: #4ecdc4;
    --success: #51cf66;
    --warning: #feca57;
    --error: #ff6b6b;
    
    /* 背景色 */
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --bg-tertiary: #1a1a1a;
    --bg-glass: rgba(255, 255, 255, 0.05);
    
    /* 文字颜色 */
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    
    /* 边框和阴影 */
    --border-color: rgba(255, 255, 255, 0.08);
    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 25px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 40px 80px rgba(0, 0, 0, 0.6);
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #4ecdc4 50%, #ff6b6b 100%);
    --gradient-secondary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-glass: linear-gradient(135deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0.05) 100%);
    
    /* 动画 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s ease;
}

/* ==================== 全局样式 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 动态背景 */
.bg-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: 
        radial-gradient(circle at 20% 80%, rgba(0, 212, 255, 0.06) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 107, 107, 0.06) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(78, 205, 196, 0.05) 0%, transparent 50%);
}

/* ==================== 容器 ==================== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ==================== 玻璃拟态效果 ==================== */
.glass {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
}

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition-normal);
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
}

.navbar.scrolled {
    padding: 12px 0;
    box-shadow: var(--shadow-sm);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 26px;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
    transition: transform var(--transition-normal);
}

.logo:hover {
    transform: scale(1.05);
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: var(--gradient-primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    color: white;
    -webkit-text-fill-color: white;
}

/* 导航菜单 */
.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
    margin-left: auto;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 15px;
    position: relative;
    padding: 8px 0;
    transition: color var(--transition-normal);
}

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

.nav-link::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width var(--transition-normal);
    border-radius: 2px;
}

.nav-link:hover::before,
.nav-link.active::before {
    width: 100%;
}

/* 导航按钮 */
.nav-btn {
    background: var(--gradient-primary);
    color: #ffffff;
    border: none;
    padding: 12px 28px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 15px;
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
    box-shadow: 0 4px 15px rgba(0, 212, 255, 0.3);
}

.nav-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 212, 255, 0.4);
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 8px;
    background: transparent;
    border: none;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-normal);
    border-radius: 2px;
}

/* ==================== Hero 区域 ==================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 140px 0 100px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: 
        radial-gradient(circle at 30% 20%, rgba(0, 212, 255, 0.08) 0%, transparent 40%),
        radial-gradient(circle at 70% 80%, rgba(255, 107, 107, 0.08) 0%, transparent 40%);
    animation: rotate 30s linear infinite;
    pointer-events: none;
}

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

.hero-content {
    text-align: center;
    max-width: 900px;
    position: relative;
    z-index: 2;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid rgba(0, 212, 255, 0.3);
    color: var(--primary);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 32px;
    backdrop-filter: blur(10px);
}

.hero-title {
    font-size: clamp(42px, 6vw, 72px);
    font-weight: 900;
    line-height: 1.15;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

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

.hero-subtitle {
    font-size: clamp(16px, 2vw, 20px);
    color: var(--text-secondary);
    max-width: 640px;
    margin: 0 auto 48px;
    line-height: 1.8;
}

.hero-subtitle strong {
    color: var(--primary);
    font-weight: 700;
}

/* 统计数据 */
.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    max-width: 700px;
    margin: 0 auto 48px;
}

.stat-card {
    padding: 28px 20px;
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.stat-card:hover::before {
    transform: scaleX(1);
}

.stat-number {
    font-size: 42px;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
    margin-bottom: 8px;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
}

/* Hero CTA按钮 */
.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-cta-primary {
    background: var(--gradient-primary);
    color: #ffffff;
    border: none;
    padding: 16px 40px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 8px 25px rgba(0, 212, 255, 0.35);
}

.hero-cta-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(0, 212, 255, 0.45);
}

.hero-cta-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 16px 40px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: 10px;
    backdrop-filter: blur(10px);
}

.hero-cta-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--primary);
    transform: translateY(-3px);
}

/* ==================== 通用 Section ==================== */
section {
    position: relative;
}

.section-padding {
    padding: 120px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-title {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 800;
    margin-bottom: 16px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    font-size: clamp(16px, 2vw, 18px);
    color: var(--text-secondary);
    max-width: 560px;
    margin: 0 auto;
}

/* ==================== 功能区域 ==================== */
.features {
    background: var(--bg-secondary);
}

.features::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--primary), transparent);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 28px;
}

.feature-card {
    padding: 36px;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.feature-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 100%;
    background: linear-gradient(135deg, rgba(0, 212, 255, 0.05) 0%, transparent 100%);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(0, 212, 255, 0.2);
}

.feature-card:hover::after {
    opacity: 1;
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: 24px;
    position: relative;
    z-index: 1;
}

.feature-card h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 12px;
    position: relative;
    z-index: 1;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
    position: relative;
    z-index: 1;
}

/* ==================== 界面展示区域 ==================== */
.showcase {
    background: var(--bg-primary);
}

/* ==================== 优势区域 ==================== */
.advantages {
    background: var(--bg-primary);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 28px;
}

.advantage-card {
    padding: 32px;
    display: flex;
    align-items: flex-start;
    gap: 16px;
    transition: all var(--transition-normal);
}

.advantage-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.advantage-icon {
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
    color: white;
}

.advantage-content h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

.advantage-content p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.6;
}

/* ==================== 下载预览卡片 ==================== */
.download-preview-card {
    display: block;
    text-align: center;
    padding: 40px 30px;
    transition: all var(--transition-normal);
    text-decoration: none;
    position: relative;
}

.download-preview-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.download-preview-card h3 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.download-preview-card .download-version {
    color: var(--primary);
    font-size: 14px;
    margin-bottom: 16px;
}

.download-preview-card .download-icon {
    margin: 0 auto 20px;
}

.download-arrow {
    font-size: 24px;
    color: var(--primary);
    opacity: 0;
    transform: translateX(-10px);
    transition: all var(--transition-normal);
}

.download-preview-card:hover .download-arrow {
    opacity: 1;
    transform: translateX(0);
}

.download-cta {
    text-align: center;
    margin-top: 48px;
}

/* ==================== 下载区域 ==================== */
.download {
    background: var(--bg-primary);
}

.download-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    max-width: 700px;
    margin: 0 auto;
}

.download-card {
    padding: 40px;
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
}

.download-card.featured {
    border-color: var(--primary);
    box-shadow: var(--shadow-md);
}

.download-card.featured::before {
    content: '推荐';
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient-primary);
    color: #ffffff;
    padding: 4px 16px;
    border-radius: 50px;
    font-size: 12px;
    font-weight: 700;
}

.download-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.download-icon {
    width: 72px;
    height: 72px;
    background: var(--gradient-primary);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    margin: 0 auto 20px;
}

.download-card h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 8px;
}

.download-version {
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 6px;
}

.download-requirement {
    color: var(--text-muted);
    font-size: 13px;
    margin-bottom: 24px;
}

.download-info {
    background: rgba(255, 255, 255, 0.02);
    padding: 16px;
    border-radius: 12px;
    margin-bottom: 24px;
    text-align: left;
}

.download-info p {
    color: var(--text-secondary);
    font-size: 13px;
    margin-bottom: 8px;
}

.download-info p:last-child {
    margin-bottom: 0;
}

.download-btn-card {
    background: var(--gradient-primary);
    color: #ffffff;
    border: none;
    padding: 14px 32px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 15px;
    cursor: pointer;
    transition: all var(--transition-normal);
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.download-btn-card:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-md);
}

.download-tips {
    background: rgba(78, 205, 196, 0.1);
    padding: 16px;
    border-radius: 12px;
    margin-top: 24px;
    text-align: left;
    border: 1px solid rgba(78, 205, 196, 0.2);
}

.download-tips h4 {
    color: var(--accent);
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
}

.download-tips p {
    color: var(--text-secondary);
    font-size: 13px;
    line-height: 1.6;
}

/* ==================== FAQ区域 ==================== */
.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 28px;
}

.faq-card {
    padding: 32px;
}

.faq-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.faq-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.6;
}

/* ==================== 页脚 ==================== */
.footer {
    background: var(--bg-secondary);
    padding: 80px 0 32px;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 56px;
}

.footer-brand .logo {
    display: inline-flex;
    margin-bottom: 16px;
}

.footer-brand p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 14px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.footer-column h4 {
    color: var(--text-primary);
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer-column a {
    display: block;
    color: var(--text-secondary);
    text-decoration: none;
    margin-bottom: 12px;
    font-size: 14px;
    transition: color var(--transition-normal);
}

.footer-column a:hover {
    color: var(--primary);
}

.footer-bottom {
    border-top: 1px solid var(--border-color);
    padding-top: 24px;
    text-align: center;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.social-links {
    display: flex;
    gap: 20px;
}

.social-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: color var(--transition-normal);
}

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

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

.animate-in {
    animation: fadeInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 1024px) {
    .container {
        padding: 0 20px;
    }

    .hero-stats {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }

    .footer-links {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .nav-actions {
        display: none;
    }

    .hero-stats {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .stat-number {
        font-size: 36px;
    }

    .features-grid,
    .download-grid,
    .advantages-grid,
    .faq-grid {
        grid-template-columns: 1fr;
    }

    .download-card.featured {
        transform: none;
    }

    .download-card.featured:hover {
        transform: translateY(-8px);
    }

    .hero-actions,
    .footer-bottom {
        flex-direction: column;
        gap: 16px;
    }

    .hero-cta-primary,
    .hero-cta-secondary {
        width: 100%;
        justify-content: center;
    }

    .footer-links {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .section-padding {
        padding: 80px 0;
    }

    .hero-title {
        font-size: 36px;
    }

    .feature-card,
    .download-card,
    .download-preview-card,
    .advantage-card,
    .faq-card {
        padding: 24px;
    }

    .download-icon {
        width: 56px;
        height: 56px;
        font-size: 24px;
    }

    .feature-icon {
        width: 48px;
        height: 48px;
        font-size: 20px;
    }
}