/* 平板端 (768px - 991px) */
@media (max-width: 991px) {
    .container {
        padding: 0 var(--space-4);
    }
    
    .hero-grid {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }
    
    .hero-visual {
        order: -1;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .demo-grid {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }
    
    .nav-menu {
        margin-left: var(--space-4);
        gap: var(--space-4);
    }
    
    .nav-right .btn-outline {
        display: none;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--space-4);
        text-align: center;
    }
}

/* 移动端 (576px - 767px) */
@media (max-width: 767px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: var(--space-4);
        gap: 0;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-lg);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-item {
        width: 100%;
    }
    
    .nav-link {
        padding: var(--space-3) var(--space-2);
        width: 100%;
        justify-content: space-between;
        border-bottom: 1px solid var(--border-color);
    }
    
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        display: none;
        min-width: auto;
        box-shadow: none;
        border: none;
        padding: var(--space-2) 0 var(--space-2) var(--space-4);
    }
    
    .nav-item.open .dropdown-menu {
        display: block;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-title {
        font-size: var(--font-size-3xl);
    }
    
    .hero-subtitle {
        font-size: var(--font-size-base);
    }
    
    .section-header h2 {
        font-size: var(--font-size-2xl);
    }
    
    .section-header p {
        font-size: var(--font-size-base);
    }
    
    .solutions-grid {
        grid-template-columns: 1fr;
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    .cta-buttons {
        flex-direction: column;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 小移动端 (<= 575px) */
@media (max-width: 575px) {
    .hero-title {
        font-size: var(--font-size-2xl);
    }
    
    .hero-stats {
        grid-template-columns: 1fr;
    }
    
    .battery-status {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .partners-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
    }
}