/* ========== 基础样式 ========== */
:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --secondary: #6366f1;
    --dark: #1e293b;
    --gray: #64748b;
    --light-gray: #f1f5f9;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #3b82f6, #8b5cf6);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--dark);
    line-height: 1.6;
    background: var(--white);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ========== 导航栏 ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #e2e8f0;
    z-index: 1000;
    padding: 16px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    font-weight: 700;
    font-size: 20px;
    color: var(--dark);
}

.logo-img {
    height: 32px;
    width: auto;
}

.logo-icon {
    font-size: 28px;
}

.footer-logo {
    height: 40px;
    width: auto;
    margin-bottom: 8px;
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray);
    font-weight: 500;
    transition: color 0.2s;
}

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

/* ========== 按钮 ========== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
    font-size: 14px;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.btn-secondary {
    background: var(--light-gray);
    color: var(--dark);
}

.btn-secondary:hover {
    background: #e2e8f0;
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

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

.btn-large {
    padding: 14px 28px;
    font-size: 16px;
}

/* ========== Hero 区域 ========== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-title {
    font-size: 52px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
}

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

.hero-subtitle {
    font-size: 18px;
    color: var(--gray);
    margin-bottom: 32px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: flex;
    gap: 48px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 28px;
    font-weight: 700;
    color: var(--primary);
}

.stat-label {
    font-size: 14px;
    color: var(--gray);
}

/* Hero 模拟图 */
.hero-mockup {
    perspective: 1000px;
}

.mockup-screen {
    background: var(--dark);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 25px 50px rgba(0,0,0,0.15);
    transform: rotateY(-5deg) rotateX(5deg);
}

.mockup-header {
    background: #374151;
    padding: 12px 16px;
    display: flex;
    gap: 8px;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #f59e0b; }
.dot.green { background: #10b981; }

.mockup-content {
    display: flex;
    height: 300px;
}

.mockup-sidebar {
    width: 60px;
    background: #1f2937;
}

.mockup-main {
    flex: 1;
    padding: 20px;
    background: #111827;
}

.mockup-video {
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    height: 180px;
    border-radius: 8px;
    margin-bottom: 16px;
}

.mockup-controls {
    height: 40px;
    background: #1f2937;
    border-radius: 6px;
}

/* ========== 功能预览 ========== */
.features-preview {
    padding: 80px 0;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 12px;
}

.section-subtitle {
    font-size: 18px;
    color: var(--gray);
    text-align: center;
    margin-bottom: 48px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--white);
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    padding: 32px;
    text-align: center;
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0,0,0,0.08);
    border-color: var(--primary);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--gray);
    font-size: 14px;
}

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

/* ========== 使用流程 ========== */
.how-it-works {
    padding: 80px 0;
    background: var(--light-gray);
}

.steps {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
}

.step {
    text-align: center;
    padding: 32px;
    background: var(--white);
    border-radius: 16px;
    flex: 1;
    max-width: 280px;
}

.step-number {
    width: 48px;
    height: 48px;
    background: var(--gradient);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: 700;
    margin: 0 auto 16px;
}

.step h3 {
    margin-bottom: 8px;
}

.step p {
    color: var(--gray);
    font-size: 14px;
}

.step-arrow {
    font-size: 32px;
    color: var(--primary);
}

/* ========== CTA ========== */
.cta-section {
    padding: 80px 0;
    background: var(--gradient);
    text-align: center;
    color: white;
}

.cta-section h2 {
    font-size: 36px;
    margin-bottom: 16px;
}

.cta-section p {
    font-size: 18px;
    opacity: 0.9;
    margin-bottom: 32px;
}

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

/* ========== 页脚 ========== */
.footer {
    padding: 60px 0 30px;
    background: var(--dark);
    color: white;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    margin-bottom: 40px;
}

.footer-brand .logo-icon,
.footer-brand .logo-text {
    display: inline;
}

.footer-brand p {
    color: var(--gray);
    margin-top: 8px;
}

.footer-links {
    display: flex;
    gap: 80px;
}

.footer-column h4 {
    margin-bottom: 16px;
}

.footer-column a {
    display: block;
    color: var(--gray);
    text-decoration: none;
    margin-bottom: 8px;
    transition: color 0.2s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid #374151;
    color: var(--gray);
}

/* ========== 页面标题 ========== */
.page-header {
    padding: 140px 0 60px;
    background: var(--light-gray);
    text-align: center;
}

.page-header h1 {
    font-size: 42px;
    margin-bottom: 12px;
}

.page-header p {
    color: var(--gray);
    font-size: 18px;
}

/* ========== 功能详情页 ========== */
.feature-detail {
    padding: 80px 0;
}

.feature-detail.alt-bg {
    background: var(--light-gray);
}

.feature-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.feature-row.reverse {
    direction: rtl;
}

.feature-row.reverse > * {
    direction: ltr;
}

.feature-badge {
    display: inline-block;
    background: var(--gradient);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 16px;
}

.feature-info h2 {
    font-size: 32px;
    margin-bottom: 16px;
}

.feature-info > p {
    color: var(--gray);
    margin-bottom: 24px;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    padding: 8px 0;
    font-size: 15px;
}

.feature-visual {
    display: flex;
    justify-content: center;
}

.feature-demo {
    background: var(--light-gray);
    border-radius: 16px;
    padding: 32px;
    width: 100%;
    max-width: 400px;
}

/* ========== 下载页 ========== */
.download-section {
    padding: 60px 0;
}

.download-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
    max-width: 800px;
    margin: 0 auto;
}

.download-card {
    background: var(--white);
    border: 2px solid #e2e8f0;
    border-radius: 16px;
    padding: 40px;
    text-align: center;
    transition: all 0.3s;
}

.download-card:hover {
    border-color: var(--primary);
    box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}

.os-icon {
    font-size: 64px;
    margin-bottom: 16px;
}

.download-card h2 {
    margin-bottom: 8px;
}

.download-card .version {
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 4px;
}

.download-card .requirements,
.download-card .size {
    color: var(--gray);
    font-size: 14px;
    margin-bottom: 4px;
}

.download-btn {
    margin-top: 24px;
    width: 100%;
    justify-content: center;
}

/* 安装指南 */
.install-guide {
    padding: 60px 0;
    background: var(--light-gray);
}

.guide-tabs {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 32px;
}

.guide-tab {
    padding: 12px 32px;
    background: var(--white);
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s;
}

.guide-tab.active {
    background: var(--primary);
    color: white;
}

.guide-panel {
    display: none;
    max-width: 600px;
    margin: 0 auto;
}

.guide-panel.active {
    display: block;
}

.install-steps {
    list-style: none;
}

.install-steps li {
    display: flex;
    gap: 20px;
    margin-bottom: 24px;
    background: var(--white);
    padding: 24px;
    border-radius: 12px;
}

.step-num {
    width: 36px;
    height: 36px;
    background: var(--gradient);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

.step-content h4 {
    margin-bottom: 4px;
}

.step-content p {
    color: var(--gray);
    font-size: 14px;
}

/* 更新日志 */
.changelog {
    padding: 60px 0;
}

.changelog-list {
    max-width: 600px;
    margin: 0 auto;
}

.changelog-item {
    border-left: 3px solid var(--primary);
    padding-left: 24px;
    margin-bottom: 32px;
}

.changelog-header {
    display: flex;
    gap: 16px;
    align-items: center;
    margin-bottom: 12px;
}

.changelog-version {
    background: var(--gradient);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
}

.changelog-date {
    color: var(--gray);
    font-size: 14px;
}

.changelog-changes {
    list-style: disc;
    padding-left: 20px;
    color: var(--gray);
}

.changelog-changes li {
    margin-bottom: 4px;
}

/* ========== 定价页 ========== */
.free-tier {
    padding: 60px 0;
}

.free-card {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
    background: linear-gradient(135deg, #f0f9ff, #e0f2fe);
    border-radius: 20px;
    padding: 40px;
}

.free-badge {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 16px;
}

.free-card h2 {
    font-size: 28px;
    margin-bottom: 8px;
}

.free-desc {
    color: var(--gray);
    margin-bottom: 24px;
}

.free-features {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    margin-bottom: 24px;
}

.free-feature {
    background: var(--white);
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 14px;
}

.pricing-section {
    padding: 60px 0;
}

.pricing-section.alt-bg {
    background: var(--light-gray);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
    max-width: 900px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--white);
    border: 2px solid #e2e8f0;
    border-radius: 16px;
    padding: 32px;
    text-align: center;
    position: relative;
    transition: all 0.3s;
}

.pricing-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0,0,0,0.08);
}

.pricing-card.popular {
    border-color: var(--primary);
}

.popular-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient);
    color: white;
    padding: 4px 16px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.pricing-card h3 {
    font-size: 18px;
    margin-bottom: 16px;
    color: var(--gray);
}

.price {
    margin-bottom: 8px;
}

.currency {
    font-size: 24px;
    vertical-align: top;
}

.amount {
    font-size: 48px;
    font-weight: 700;
}

.bonus {
    color: #10b981;
    font-weight: 600;
    margin-bottom: 8px;
}

.total {
    color: var(--gray);
    font-size: 14px;
    margin-bottom: 24px;
}

.pricing-features {
    list-style: none;
    text-align: left;
    margin-bottom: 24px;
}

.pricing-features li {
    padding: 8px 0;
    font-size: 14px;
    color: var(--gray);
}

.pricing-card .btn {
    width: 100%;
    justify-content: center;
}

/* FAQ */
.faq-section {
    padding: 60px 0;
}

.faq-list {
    max-width: 700px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid #e2e8f0;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    cursor: pointer;
    font-weight: 500;
}

.faq-toggle {
    font-size: 24px;
    color: var(--primary);
}

.faq-answer {
    display: none;
    padding-bottom: 20px;
    color: var(--gray);
}

.faq-item.open .faq-answer {
    display: block;
}

/* ========== 响应式 ========== */

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 1001;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--dark);
    border-radius: 2px;
    transition: all 0.3s ease;
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }
    
    .navbar .container {
        position: relative;
    }
    
    .navbar .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(10px);
        flex-direction: column;
        padding: 20px 24px;
        gap: 0;
        border-top: 1px solid #e2e8f0;
        box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    }
    
    .navbar .nav-links.active {
        display: flex;
    }
    
    .navbar .nav-links a {
        padding: 14px 0;
        border-bottom: 1px solid #f1f5f9;
        font-size: 16px;
        color: #1e293b !important;  /* 深色文字，确保可见 */
    }
    
    .navbar .nav-links a:hover,
    .navbar .nav-links a.active {
        color: #3b82f6 !important;  /* 悬停/激活状态为主色 */
    }
    
    .navbar .nav-links a:last-child {
        border-bottom: none;
    }
    
    .navbar .btn-primary {
        display: none;
    }
    
    .hero .container {
        grid-template-columns: 1fr;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-image {
        display: none;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .steps {
        flex-direction: column;
    }
    
    .step-arrow {
        transform: rotate(90deg);
    }
    
    .feature-row {
        grid-template-columns: 1fr;
    }
    
    .download-cards {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 40px;
    }
    
    .footer-links {
        gap: 40px;
    }
    
    .page-header {
        padding: 100px 0 40px;
    }
    
    .page-header h1 {
        font-size: 28px;
    }
    
    .section-title {
        font-size: 28px;
    }
}