/* 响应式设计 */
@media (max-width: 1024px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .features h2,
    .download-cta h2,
    .section-header h2 {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
        gap: 3rem;
    }
    
    .hero-actions {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .hero-features {
        justify-content: center;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: var(--bg-color);
        flex-direction: column;
        padding: 2rem;
        box-shadow: var(--shadow);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .mobile-menu-btn.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    
    .download-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .download-btn {
        width: 100%;
        max-width: 300px;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .btn-large {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }
    
    .features h2,
    .download-cta h2,
    .section-header h2 {
        font-size: 1.75rem;
    }
    
    .feature-card,
    .tutorial-item,
    .news-card {
        padding: 1.5rem;
    }
    
    .download-btn {
        height: 80px;
    }
    
    .download-btn span {
        font-size: 1rem;
    }
}