@media screen and (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background: var(--white);
    }

    .nav-menu.active {
        display: block;
    }

    .nav-toggle {
        display: block;
    }

    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .testimonial-grid {
        grid-template-columns: 1fr;
    }

    .product-grid {
        grid-template-columns: 1fr;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 2rem;
    }
}

@media screen and (max-width: 480px) {
    .feature-grid {
        grid-template-columns: 1fr;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }
}

/* 其他响应式样式... */