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

/* CSS变量定义 */
:root {
    --primary-color: #4285F4;
    --secondary-color: #34A853;
    --accent-color: #FBBC05;
    --error-color: #EA4335;
    --background-color: #ffffff;
    --text-color: #202124;
    --text-secondary: #5f6368;
    --border-color: #e0e0e0;
    --section-background: #f8f9fa;
    --card-background: #ffffff;
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 8px rgba(0, 0, 0, 0.1);
    --border-radius: 4px;
    --transition: all 0.3s ease;
}

/* 深色模式 */
@media (prefers-color-scheme: dark) {
    :root {
        --background-color: #202124;
        --text-color: #ffffff;
        --text-secondary: #dadce0;
        --border-color: #3c4043;
        --section-background: #303134;
        --card-background: #303134;
        --shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
        --shadow-hover: 0 4px 8px rgba(0, 0, 0, 0.3);
    }
}

/* 全局样式 */
body {
    font-family: 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
    transition: var(--transition);
}

/* 容器样式 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: var(--transition);
}

@media (prefers-color-scheme: dark) {
    .header {
        background-color: rgba(32, 33, 36, 0.95);
    }
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.nav-logo svg {
    width: 100px;
    height: 32px;
    fill: var(--text-color);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
}

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

.nav-links .btn-primary {
    background-color: var(--primary-color);
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

.nav-links .btn-primary:hover {
    background-color: #3367d6;
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 2px;
    background-color: var(--text-color);
    transition: var(--transition);
}

/* 按钮样式 */
.btn-primary {
    background-color: var(--primary-color);
    color: white;
    padding: 0.75rem 2rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-primary:hover {
    background-color: #3367d6;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    padding: 0.75rem 2rem;
    border: 2px solid var(--primary-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

/* 英雄区域样式 */
.hero {
    padding: 120px 0 80px;
    background-color: var(--background-color);
    position: relative;
    overflow: hidden;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 500px;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    color: var(--text-color);
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    color: var(--text-secondary);
}

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

.hero-image {
    position: absolute;
    top: 50%;
    right: 10%;
    transform: translateY(-50%);
    z-index: 1;
    opacity: 0.8;
}

.hero-image svg {
    width: 600px;
    height: 400px;
}

/* 特性区域样式 */
.features {
    padding: 80px 0;
    background-color: var(--section-background);
}

.features h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

.section-description {
    font-size: 1.25rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

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

.feature-card {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

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

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-color);
}

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

/* 性能区域样式 */
.performance {
    padding: 80px 0;
    background-color: var(--background-color);
}

.performance h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

.performance-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.stat-item {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.stat-label {
    font-size: 1rem;
    color: var(--text-secondary);
}

/* 安全区域样式 */
.security {
    padding: 80px 0;
    background-color: var(--section-background);
}

.security h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

.security-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.security-item {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.security-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.security-item h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.security-item p {
    color: var(--text-secondary);
}

/* 评价区域样式 */
.testimonial {
    padding: 80px 0;
    background-color: var(--background-color);
}

.testimonial h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
    text-align: center;
    color: var(--text-color);
}

.testimonial-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 3rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.testimonial-content p {
    font-size: 1.25rem;
    font-style: italic;
    margin-bottom: 2rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.testimonial-author {
    text-align: center;
}

.author-name {
    font-weight: 600;
    color: var(--text-color);
    display: block;
    margin-bottom: 0.5rem;
}

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

/* 下载CTA区域样式 */
.download-cta {
    padding: 80px 0;
    background-color: var(--primary-color);
    text-align: center;
    color: white;
}

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

.download-cta p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.download-cta .btn-primary {
    background-color: white;
    color: var(--primary-color);
}

.download-cta .btn-primary:hover {
    background-color: #f8f9fa;
    transform: translateY(-2px);
}

/* 下载页面英雄区域 */
.download-hero {
    padding: 120px 0 60px;
    background-color: var(--primary-color);
    text-align: center;
    color: white;
}

.download-hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

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

/* 下载选项区域 */
.download-options {
    padding: 80px 0;
    background-color: var(--background-color);
}

.download-options h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

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

.platform-item {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.platform-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

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

.platform-item h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.platform-item p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

/* 系统要求区域 */
.system-requirements {
    padding: 80px 0;
    background-color: var(--section-background);
}

.system-requirements h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.requirement-item {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.requirement-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.requirement-item h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.requirement-item ul {
    list-style-type: none;
    color: var(--text-secondary);
}

.requirement-item li {
    margin-bottom: 0.75rem;
    position: relative;
    padding-left: 1.5rem;
}

.requirement-item li::before {
    content: '•';
    color: var(--primary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* FAQ区域 */
.faq {
    padding: 80px 0;
    background-color: var(--background-color);
}

.faq h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
    color: var(--text-color);
}

.faq-items {
    max-width: 800px;
    margin: 3rem auto 0;
}

.faq-item {
    margin-bottom: 1rem;
    border-radius: var(--border-radius);
    overflow: hidden;
    background-color: var(--card-background);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background-color: var(--card-background);
    border: none;
    text-align: left;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-color);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.faq-question:hover {
    background-color: var(--section-background);
}

.faq-question::after {
    content: '+';
    position: absolute;
    right: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.5rem;
    font-weight: bold;
    transition: var(--transition);
}

.faq-item.active .faq-question::after {
    content: '−';
}

.faq-answer {
    padding: 0 1.5rem;
    max-height: 0;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item.active .faq-answer {
    padding: 0 1.5rem 1.5rem;
    max-height: 200px;
}

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

/* 页脚样式 */
.footer {
    padding: 60px 0;
    background-color: var(--section-background);
    border-top: 1px solid var(--border-color);
}

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

.footer-logo svg {
    width: 120px;
    height: 40px;
    fill: var(--text-color);
    margin-bottom: 2rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    justify-content: center;
}

.footer-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
}

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

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

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background-color: var(--background-color);
        flex-direction: column;
        align-items: center;
        padding: 2rem 0;
        gap: 1.5rem;
        box-shadow: var(--shadow);
        transform: translateY(-150%);
        opacity: 0;
        transition: var(--transition);
        border-bottom: 1px solid var(--border-color);
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
    }

    .nav-toggle {
        display: flex;
    }

    .hero {
        padding: 100px 0 60px;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
        margin-bottom: 2rem;
    }

    .hero-image {
        position: relative;
        top: 0;
        right: 0;
        transform: none;
        margin-top: 2rem;
    }

    .hero-image svg {
        width: 100%;
        max-width: 400px;
        height: auto;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

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

    .features h2,
    .performance h2,
    .security h2,
    .testimonial h2,
    .download-cta h2,
    .download-hero h1,
    .download-options h2,
    .system-requirements h2,
    .faq h2 {
        font-size: 2rem;
    }

    .section-description {
        font-size: 1.1rem;
    }

    .performance-stats {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }

    .stat-number {
        font-size: 2.5rem;
    }

    .testimonial-content {
        padding: 2rem;
    }

    .testimonial-content p {
        font-size: 1.1rem;
    }

    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .btn-primary,
    .btn-secondary {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }

    .features-grid,
    .security-features,
    .platforms,
    .requirements-grid {
        grid-template-columns: 1fr;
    }

    .feature-card,
    .security-item,
    .platform-item,
    .requirement-item {
        padding: 1.5rem;
    }

    .faq-question {
        padding: 1.25rem;
        font-size: 1rem;
    }

    .faq-answer {
        padding: 0 1.25rem;
    }

    .faq-item.active .faq-answer {
        padding: 0 1.25rem 1.25rem;
    }

    .testimonial-content {
        padding: 1.5rem;
    }

    .testimonial-content p {
        font-size: 1rem;
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--section-background);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #3367d6;
}

/* 选择文本样式 */
::selection {
    background-color: var(--primary-color);
    color: white;
}

/* 焦点样式 */
:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* 动画延迟 */
.feature-card:nth-child(1) {
    animation-delay: 0.1s;
}

.feature-card:nth-child(2) {
    animation-delay: 0.2s;
}

.feature-card:nth-child(3) {
    animation-delay: 0.3s;
}

.feature-card:nth-child(4) {
    animation-delay: 0.4s;
}

.stat-item:nth-child(1) {
    animation-delay: 0.1s;
}

.stat-item:nth-child(2) {
    animation-delay: 0.2s;
}

.stat-item:nth-child(3) {
    animation-delay: 0.3s;
}

.stat-item:nth-child(4) {
    animation-delay: 0.4s;
}

.security-item:nth-child(1) {
    animation-delay: 0.1s;
}

.security-item:nth-child(2) {
    animation-delay: 0.2s;
}

.security-item:nth-child(3) {
    animation-delay: 0.3s;
}

.security-item:nth-child(4) {
    animation-delay: 0.4s;
}

.platform-item:nth-child(1) {
    animation-delay: 0.1s;
}

.platform-item:nth-child(2) {
    animation-delay: 0.2s;
}

.platform-item:nth-child(3) {
    animation-delay: 0.3s;
}

.platform-item:nth-child(4) {
    animation-delay: 0.4s;
}

.requirement-item:nth-child(1) {
    animation-delay: 0.1s;
}

.requirement-item:nth-child(2) {
    animation-delay: 0.2s;
}

.requirement-item:nth-child(3) {
    animation-delay: 0.3s;
}

.requirement-item:nth-child(4) {
    animation-delay: 0.4s;
}

.faq-item:nth-child(1) {
    animation-delay: 0.1s;
}

.faq-item:nth-child(2) {
    animation-delay: 0.2s;
}

.faq-item:nth-child(3) {
    animation-delay: 0.3s;
}

.faq-item:nth-child(4) {
    animation-delay: 0.4s;
}

.faq-item:nth-child(5) {
    animation-delay: 0.5s;
}

.faq-item:nth-child(6) {
    animation-delay: 0.6s;
}

/* 淡入动画 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    animation: fadeIn 0.6s ease-out forwards;
}