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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #8b5cf6;
    --accent-color: #ec4899;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ============================================
   头部导航
   ============================================ */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header.scrolled {
    box-shadow: var(--shadow-lg);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    font-weight: bold;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s;
}

/* ============================================
   Hero区域
   ============================================ */
.hero {
    background: var(--bg-gradient);
    color: white;
    padding: 120px 20px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50% { transform: translate(-30px, -30px) rotate(180deg); }
}

.hero-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.hero-content {
    text-align: left;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    margin-bottom: 2rem;
    opacity: 0.95;
}

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

.hero-stats {
    display: flex;
    gap: 3rem;
    flex-wrap: wrap;
}

.hero-image {
    position: relative;
    text-align: center;
}

.hero-img {
    max-width: 100%;
    height: auto;
    border-radius: 20px;
    box-shadow: 0 25px 80px rgba(0, 0, 0, 0.4);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    border: 3px solid rgba(255, 255, 255, 0.2);
    position: relative;
    z-index: 1;
}

.hero-img:hover {
    transform: scale(1.05) rotate(1deg);
    box-shadow: 0 35px 100px rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 255, 255, 0.4);
}

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

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #ffffff 0%, rgba(255, 255, 255, 0.8) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.95;
    font-weight: 500;
    letter-spacing: 0.5px;
}

.stat-item {
    position: relative;
    padding: 1rem;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.stat-item:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: scale(1.05);
}

/* ============================================
   按钮样式
   ============================================ */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    border: none;
    transition: all 0.3s;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.btn-primary:hover::before {
    left: 100%;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-color) 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(99, 102, 241, 0.4);
}

.btn-outline {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-outline:hover {
    background: white;
    color: var(--primary-color);
}

.btn-large {
    padding: 16px 32px;
    font-size: 1.1rem;
}

/* ============================================
   功能展示区域
   ============================================ */
.features-section {
    padding: 80px 20px;
    background: var(--bg-white);
}

.section-title {
    text-align: center;
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

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

.feature-card {
    background: var(--bg-white);
    padding: 2.5rem;
    border-radius: 16px;
    text-align: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--bg-gradient);
    transform: scaleX(0);
    transition: transform 0.4s ease;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-light);
}

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

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

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

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

/* ============================================
   用户评价区域
   ============================================ */
.reviews-section {
    padding: 80px 20px;
    background: var(--bg-light);
}

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

.review-card {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    position: relative;
}

.review-card::after {
    content: '"';
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 4rem;
    color: var(--primary-light);
    opacity: 0.2;
    font-family: Georgia, serif;
}

.review-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.review-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.review-avatar {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
}

.review-name {
    font-weight: 600;
    color: var(--text-primary);
}

.review-rating {
    color: #fbbf24;
    font-size: 0.9rem;
}

.review-text {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.review-date {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* ============================================
   对比表格
   ============================================ */
.comparison-section {
    padding: 80px 20px;
    background: var(--bg-white);
}

.comparison-table {
    overflow-x: auto;
    margin-bottom: 2rem;
}

.comparison-table table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.comparison-table th,
.comparison-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.comparison-table th {
    background: var(--bg-light);
    font-weight: 600;
    color: var(--text-primary);
}

.comparison-table th.highlight {
    background: var(--primary-color);
    color: white;
}

.comparison-table td.highlight {
    background: #eff6ff;
    font-weight: 600;
    color: var(--primary-color);
}

.comparison-table tr:last-child td {
    border-bottom: none;
}

.comparison-cta {
    text-align: center;
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   教程预览
   ============================================ */
.tutorial-preview-section {
    padding: 80px 20px;
    background: var(--bg-light);
}

.tutorial-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.tutorial-step {
    text-align: center;
}

.step-number {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 auto 1rem;
}

.tutorial-step h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

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

.tutorial-cta {
    text-align: center;
}

/* ============================================
   更新日志
   ============================================ */
.changelog-section {
    padding: 80px 20px;
    background: var(--bg-white);
}

.changelog-list {
    max-width: 800px;
    margin: 0 auto;
}

.changelog-item {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: 16px;
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--primary-color);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.changelog-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-lg);
    border-left-width: 6px;
}

.changelog-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.changelog-version {
    font-weight: 600;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.changelog-date {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.changelog-content {
    list-style: none;
    padding-left: 0;
}

.changelog-content li {
    padding: 0.5rem 0;
    color: var(--text-secondary);
    padding-left: 1.5rem;
    position: relative;
}

.changelog-content li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

/* ============================================
   SEO内容区域
   ============================================ */
.seo-content-section {
    padding: 80px 20px;
    background: var(--bg-light);
}

.seo-article {
    max-width: 900px;
    margin: 0 auto;
    background: var(--bg-white);
    padding: 3rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.seo-article h2 {
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.seo-article h3 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: var(--text-primary);
}

.seo-article p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1rem;
}

.seo-article strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* ============================================
   页脚
   ============================================ */
.footer {
    background: #1f2937;
    color: #9ca3af;
    padding: 60px 20px 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-column h3 {
    color: white;
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

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

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

.footer-column ul li a {
    color: #9ca3af;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-column ul li a:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
}

.footer-bottom p {
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.footer-bottom a {
    color: #9ca3af;
    text-decoration: none;
}

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

.disclaimer {
    color: var(--warning-color);
    font-weight: 600;
}

/* ============================================
   返回顶部按钮
   ============================================ */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    transition: all 0.3s;
    z-index: 999;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-5px);
}

.back-to-top.show {
    display: flex;
}

/* ============================================
   单页网站section间距
   ============================================ */
section[id] {
    scroll-margin-top: 80px;
}

.download-section {
    padding: 80px 20px;
}

/* ============================================
   响应式设计
   ============================================ */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        background: var(--bg-white);
        flex-direction: column;
        padding: 2rem;
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
        transition: left 0.3s;
    }

    .nav-menu.active {
        left: 0;
    }

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

    .hero-wrapper {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        text-align: center;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-stats {
        gap: 2rem;
        justify-content: center;
    }

    .features-grid,
    .reviews-grid {
        grid-template-columns: 1fr;
    }

    .tutorial-steps {
        grid-template-columns: 1fr;
    }

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

    .comparison-table {
        font-size: 0.875rem;
    }
}

/* ============================================
   图片懒加载
   ============================================ */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s;
}

img[loading="lazy"].loaded {
    opacity: 1;
}