/* ============================================
   客信新材料 - 响应式样式
   ============================================ */

/* --- Tablets & Small Laptops (≤1024px) --- */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        order: 2;
    }

    .hero-visual {
        order: 1;
    }

    .hero-desc {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-visual-inner {
        max-width: 380px;
        margin: 0 auto;
    }

    .hero-float:nth-child(4) {
        display: none;
    }

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

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

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

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

    .about-intro-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .about-intro-image {
        order: -1;
        aspect-ratio: 16/9;
    }

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

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

    .product-detail-grid {
        grid-template-columns: 1fr;
        padding: 30px;
    }

    .product-detail-visual {
        order: -1;
        aspect-ratio: 16/9;
        font-size: 4rem;
    }

    .process-steps {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px;
    }

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

/* --- Mobile (≤768px) --- */
@media (max-width: 768px) {
    :root {
        --section-padding: 70px 0;
    }

    .menu-toggle {
        display: flex;
    }

    .main-nav {
        position: fixed;
        top: 80px;
        left: 0;
        width: 100%;
        flex-direction: column;
        background: var(--white);
        padding: 20px;
        box-shadow: var(--shadow-lg);
        gap: 4px;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
        border-radius: 0 0 20px 20px;
    }

    .main-nav.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .main-nav a {
        padding: 14px 18px;
        width: 100%;
        font-size: 1rem;
    }

    .main-nav a::after {
        display: none;
    }

    .hero {
        min-height: auto;
        padding: 120px 0 80px;
    }

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

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

    .hero-float {
        display: none;
    }

    .hero-circle:nth-child(11),
    .hero-circle:nth-child(12),
    .hero-circle:nth-child(13) {
        display: none;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    .stat-card {
        padding: 24px 16px;
    }

    .stat-number {
        font-size: 2rem;
    }

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

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

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .page-banner {
        padding: 130px 0 60px;
    }

    .page-banner h1 {
        font-size: 1.8rem;
    }

    /* About Page Mobile */
    .timeline::before {
        left: 20px;
    }

    .timeline-item,
    .timeline-item:nth-child(even) {
        flex-direction: row;
        padding-left: 50px;
    }

    .timeline-content {
        width: 100%;
    }

    .timeline-dot {
        left: 20px;
    }

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

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

    /* Products Mobile */
    .product-tabs {
        gap: 8px;
    }

    .product-tab {
        padding: 10px 20px;
        font-size: 0.85rem;
    }

    .product-detail-grid {
        padding: 24px;
    }

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

    .product-detail-info h3 {
        font-size: 1.35rem;
    }

    .process-steps {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    /* Contact Mobile */
    .contact-form-wrap {
        padding: 28px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .cta-section h2 {
        font-size: 1.6rem;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 42px;
        height: 42px;
    }

    .whatsapp-float {
        bottom: 72px;
        right: 20px;
        width: 48px;
        height: 48px;
        font-size: 1.3rem;
    }
}

/* --- Small Mobile (≤480px) --- */
@media (max-width: 480px) {
    .hero-title {
        font-size: 1.6rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .stat-card {
        padding: 20px 12px;
    }

    .stat-number {
        font-size: 1.6rem;
    }

    .stat-icon {
        width: 48px;
        height: 48px;
        font-size: 1.2rem;
        margin-bottom: 14px;
    }

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

    .site-logo .logo-sub {
        display: none;
    }
}