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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f5f7fa;
    overflow-x: hidden;
}

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

.header {
    background: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 0;
}

.logo h1 {
    font-size: 24px;
    color: #1a73e8;
    font-weight: 700;
}

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

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #1a73e8;
}

.nav-buttons {
    display: flex;
    gap: 12px;
}

.btn {
    padding: 10px 24px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    display: inline-block;
}

.btn-primary {
    background: #1a73e8;
    color: white;
}

.btn-primary:hover {
    background: #1557b0;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.3);
}

.btn-secondary {
    background: white;
    color: #1a73e8;
    border: 2px solid #1a73e8;
}

.btn-secondary:hover {
    background: #f0f4ff;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    border-radius: 2px;
}

.hero-section {
    padding: 80px 0;
    text-align: center;
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
}

.hero-title {
    font-size: 42px;
    color: #1a237e;
    margin-bottom: 20px;
    font-weight: 700;
}

.hero-description {
    font-size: 18px;
    color: #424242;
    margin-bottom: 35px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-bottom: 50px;
}

.btn-large {
    padding: 14px 36px;
    font-size: 16px;
}

.btn-outline {
    background: transparent;
    color: #1a73e8;
    border: 2px solid #1a73e8;
}

.btn-outline:hover {
    background: white;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 80px;
    margin-top: 40px;
}

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

.stat-item h3 {
    font-size: 32px;
    color: #1a73e8;
    margin-bottom: 8px;
}

.stat-item p {
    color: #666;
    font-size: 14px;
}

.section-title {
    font-size: 36px;
    text-align: center;
    margin-bottom: 15px;
    color: #1a237e;
    font-weight: 700;
}

.section-subtitle {
    text-align: center;
    font-size: 16px;
    color: #666;
    margin-bottom: 45px;
}

.features-section {
    padding: 80px 0;
    background: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-card {
    background: #fff;
    border: 2px solid #e0e0e0;
    padding: 35px 25px;
    border-radius: 12px;
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: #1a73e8;
    box-shadow: 0 8px 24px rgba(26, 115, 232, 0.15);
}

.feature-icon {
    font-size: 40px;
    margin-bottom: 15px;
}

.feature-card h3 {
    font-size: 20px;
    color: #1a237e;
    margin-bottom: 12px;
}

.feature-card p {
    color: #666;
    line-height: 1.7;
    font-size: 14px;
}

.download-section {
    padding: 80px 0;
    background: #f5f7fa;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.download-card {
    background: white;
    padding: 35px 25px;
    border-radius: 12px;
    text-align: center;
    border: 2px solid #e0e0e0;
    transition: all 0.3s;
}

.download-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border-color: #1a73e8;
}

.card-icon {
    font-size: 48px;
    margin-bottom: 18px;
}

.download-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: #1a237e;
}

.download-card p {
    color: #666;
    margin-bottom: 20px;
    font-size: 13px;
    line-height: 1.6;
}

.btn-download {
    background: #1a73e8;
    color: white;
    padding: 10px 24px;
}

.scenario-section {
    padding: 80px 0;
    background: white;
}

.scenario-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    margin-bottom: 80px;
}

.scenario-item.reverse .scenario-image {
    order: 2;
}

.scenario-item.reverse .scenario-text {
    order: 1;
}

.scenario-image {
    height: 320px;
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
    border-radius: 12px;
    border: 2px solid #e0e0e0;
}

.scenario-text h2 {
    font-size: 28px;
    color: #1a237e;
    margin-bottom: 18px;
    font-weight: 700;
}

.scenario-text p {
    color: #666;
    margin-bottom: 25px;
    line-height: 1.7;
}

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

.scenario-list li {
    color: #424242;
    padding: 8px 0;
    font-size: 15px;
}

.faq-section {
    padding: 80px 0;
    background: #f5f7fa;
}

.faq-list {
    max-width: 900px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    border-radius: 8px;
    margin-bottom: 15px;
    overflow: hidden;
    border: 2px solid #e0e0e0;
}

.faq-question {
    width: 100%;
    padding: 20px 25px;
    background: transparent;
    border: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-size: 16px;
    color: #1a237e;
    font-weight: 600;
    text-align: left;
}

.faq-icon {
    font-size: 24px;
    color: #1a73e8;
    transition: transform 0.3s;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

.faq-answer p {
    padding: 0 25px 20px;
    color: #666;
    line-height: 1.7;
}

.cta-section {
    padding: 80px 0;
    text-align: center;
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
}

.cta-section h2 {
    font-size: 36px;
    color: #1a237e;
    margin-bottom: 18px;
    font-weight: 700;
}

.cta-section p {
    font-size: 16px;
    color: #424242;
    margin-bottom: 35px;
}

.footer {
    background: #1a237e;
    padding: 60px 0 30px;
    color: rgba(255, 255, 255, 0.8);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h4 {
    color: white;
    font-size: 16px;
    margin-bottom: 18px;
    font-weight: 600;
}

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

.footer-column a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    display: block;
    padding: 6px 0;
    font-size: 14px;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 25px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    font-size: 14px;
}

.disclaimer {
    margin-top: 8px;
    color: rgba(255, 255, 255, 0.6);
    font-size: 13px;
}

@media (max-width: 1024px) {
    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu, .nav-buttons {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 25px;
    }
    
    .download-grid, .features-grid {
        grid-template-columns: 1fr;
    }
    
    .scenario-item, .scenario-item.reverse {
        grid-template-columns: 1fr;
    }
    
    .scenario-item.reverse .scenario-image,
    .scenario-item.reverse .scenario-text {
        order: 0;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
}