@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-buttons .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        flex-direction: column;
        background-color: var(--white);
        padding: var(--spacing-lg);
        box-shadow: var(--shadow-md);
        transition: left var(--transition-normal);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-container {
        grid-template-columns: 1fr;
    }
    
    .cart-sidebar {
        width: 100%;
        right: -100%;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.5rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .publications-grid {
        grid-template-columns: 1fr;
    }
}