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

:root {
    --primary-color: #3b82f6;
    --secondary-color: #8b5cf6;
    --accent-color: #06b6d4;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: #d9d9d9;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4rem;
}

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

.brand-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
    transition: all 0.3s ease;
}

.brand-icon {
    width: 2rem;
    height: 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-md);
    margin-right: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1rem;
}

.brand-text {
    font-weight: 700;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background: rgba(59, 130, 246, 0.1);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.theme-toggle {
    background: none;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.theme-toggle:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 1.5rem;
    height: 2px;
    background: var(--text-primary);
    margin: 2px 0;
    transition: all 0.3s ease;
    border-radius: 1px;
}

/* 主要内容 */
.main-content {
    margin-top: 4rem;
}

/* 英雄区域 */
.hero-section {
    padding: 6rem 0;
    background: #d9d9d9;
    color: var(--text-primary);
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border-color);
}

.hero-section::before {
    display: none;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    animation: slideInLeft 0.8s ease-out;
}

.hero-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    padding: 0.5rem 1rem;
    border-radius: 2rem;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.title-line {
    display: block;
    animation: slideInUp 0.8s ease-out;
}

.title-line:nth-child(2) {
    animation-delay: 0.2s;
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    padding: 0.875rem 1.5rem;
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

/* 浮动卡片 */
.hero-visual {
    position: relative;
    height: 400px;
    animation: slideInRight 0.8s ease-out;
}

.floating-card {
    position: absolute;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    animation: float 3s ease-in-out infinite;
}

.card-1 {
    top: 2rem;
    right: 2rem;
    animation-delay: 0s;
}

.card-2 {
    top: 8rem;
    left: 1rem;
    animation-delay: 1s;
}

.card-3 {
    bottom: 2rem;
    right: 4rem;
    animation-delay: 2s;
}

.card-icon {
    margin-bottom: 0.5rem;
    color: white;
}

.card-text {
    font-size: 0.875rem;
    font-weight: 500;
}

/* 特色功能区域 */
.features-section {
    padding: 6rem 0;
    background: var(--bg-primary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.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: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: var(--radius-xl);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

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

.feature-icon {
    margin-bottom: 1.5rem;
}

.icon-bg {
    width: 4rem;
    height: 4rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto;
    color: white;
}

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

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

/* 介绍区域 */
.about-section {
    padding: 6rem 0;
    background: var(--bg-secondary);
}

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

.about-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.about-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 2rem;
}

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

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

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.about-visual {
    position: relative;
}

.visual-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.card-header {
    background: var(--bg-tertiary);
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.card-dots {
    display: flex;
    gap: 0.5rem;
}

.card-dots span {
    width: 0.75rem;
    height: 0.75rem;
    border-radius: 50%;
    background: var(--text-muted);
}

.card-dots span:nth-child(1) { background: #ef4444; }
.card-dots span:nth-child(2) { background: #f59e0b; }
.card-dots span:nth-child(3) { background: #10b981; }

.card-content {
    padding: 1.5rem;
}

.chat-bubble {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.user-bubble {
    justify-content: flex-end;
    flex-direction: row-reverse;
}

.ai-bubble {
    justify-content: flex-start;
}

.bubble-avatar {
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    color: white;
}

.user-bubble .bubble-avatar {
    background: var(--primary-color);
}

.ai-bubble .bubble-avatar {
    background: var(--secondary-color);
}

.bubble-text {
    background: var(--bg-tertiary);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    line-height: 1.5;
    max-width: 200px;
}

.user-bubble .bubble-text {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.ai-bubble .bubble-text {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

/* 教程区域 */
.tutorial-section {
    padding: 6rem 0;
    background: var(--bg-primary);
}

.tutorial-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.tutorial-header {
    margin-bottom: 3rem;
}

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

.tutorial-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
}

.tutorial-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-2xl);
    padding: 3rem;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

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

.tutorial-icon {
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.tutorial-card-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.tutorial-card-description {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.tutorial-link {
    display: inline-flex;
    align-items: center;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.tutorial-link:hover {
    color: var(--secondary-color);
}

.link-arrow {
    margin-left: 0.5rem;
    transition: transform 0.3s ease;
}

.tutorial-link:hover .link-arrow {
    transform: translateX(4px);
}

/* 下载区域 */
.download-section {
    padding: 6rem 0;
    background: #d9d9d9;
    color: var(--text-primary);
    border-top: 1px solid var(--border-color);
}

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

.download-header {
    margin-bottom: 3rem;
}

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

.download-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
}

.download-actions {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem 2rem;
    border-radius: var(--radius-xl);
    text-decoration: none;
    transition: all 0.3s ease;
    min-width: 200px;
}

.download-btn.primary {
    background: white;
    color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

.download-btn.primary:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

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

.download-btn.secondary:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-4px);
}

.btn-icon {
    color: currentColor;
}

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

.btn-title {
    font-weight: 600;
    font-size: 1.125rem;
    margin-bottom: 0.25rem;
}

.btn-subtitle {
    font-size: 0.875rem;
    opacity: 0.8;
}

/* 页脚 */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    margin-bottom: 2rem;
}

.footer-brand {
    max-width: 300px;
}

.footer-logo {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.footer-description {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.6;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.link-group {
    display: flex;
    flex-direction: column;
}

.link-title {
    font-weight: 600;
    margin-bottom: 1rem;
    color: white;
}

.footer-link {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

.footer-link:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
    text-align: center;
}

.copyright {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.875rem;
}

/* 全屏查看器 */
.fullscreen-viewer {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    z-index: 2000;
    justify-content: center;
    align-items: center;
}

.fullscreen-viewer img,
.fullscreen-viewer video {
    max-width: 90%;
    max-height: 90%;
    border-radius: var(--radius-lg);
}

.close-btn {
    position: absolute;
    top: 2rem;
    right: 2rem;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    font-size: 2rem;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.3s ease;
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* 动画 */
@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

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

    .hero-container {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-actions {
        justify-content: center;
        flex-wrap: wrap;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .about-stats {
        justify-content: center;
    }

    .download-actions {
        flex-direction: column;
        align-items: center;
    }

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

    .footer-links {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .hero-section {
        padding: 4rem 0;
    }

    .hero-title {
        font-size: 2rem;
    }

    .section-title {
        font-size: 2rem;
    }

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

    .tutorial-card {
        padding: 2rem;
    }
}

/* 暗色主题 */
body.dark-mode {
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --border-color: #475569;
}

body.dark-mode .navbar {
    background: rgba(15, 23, 42, 0.8);
    border-bottom-color: var(--border-color);
}

body.dark-mode .hero-section {
    background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
}