/* ============================================
   Xi'an Hongying Vibration Isolation Technology
   Global Stylesheet
   Version: 1.0
   ============================================ */

/* CSS Variables */
:root {
    --primary-color: #1a237e;
    --primary-dark: #0f1558;
    --secondary-color: #ff6b35;
    --secondary-dark: #e55a2b;
    --text-dark: #333333;
    --text-light: #666666;
    --text-white: #ffffff;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --border-color: #e0e0e0;
    --success: #28a745;
    --error: #dc3545;
    --warning: #ffc107;
    --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 5px 20px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s ease;
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: var(--bg-white);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: var(--text-dark);
    transition: var(--transition);
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 15px;
}

h1 { font-size: 48px; }
h2 { font-size: 36px; }
h3 { font-size: 24px; }
h4 { font-size: 20px; }

p {
    margin-bottom: 15px;
    color: var(--text-light);
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    margin-bottom: 15px;
}

.section-header h2 span {
    color: var(--secondary-color);
}

.section-header p {
    font-size: 18px;
    max-width: 700px;
    margin: 0 auto;
}

/* Buttons */
.btn-primary, .btn-secondary, .btn-quote {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 30px;
    border-radius: 5px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-size: 16px;
}

.btn-primary {
    background: var(--primary-color);
    color: var(--text-white);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: var(--text-white);
    transform: translateY(-2px);
}

.btn-quote {
    background: var(--secondary-color);
    color: var(--text-white);
    padding: 8px 20px;
}

.btn-quote:hover {
    background: var(--secondary-dark);
    transform: translateY(-2px);
}

.read-more {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--secondary-color);
    font-weight: 500;
}

.read-more:hover {
    gap: 12px;
}

/* Header */
header {
    background: var(--bg-white);
    box-shadow: var(--shadow-sm);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    transition: var(--transition);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo h1 {
    font-size: 24px;
    margin-bottom: 0;
}

.logo span {
    color: var(--secondary-color);
}

/* Navigation */
.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-menu li {
    position: relative;
}

.nav-menu a {
    font-weight: 500;
    padding: 8px 0;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--secondary-color);
}

/* Dropdown Menu */
.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--bg-white);
    min-width: 220px;
    box-shadow: var(--shadow-md);
    border-radius: 8px;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 100;
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
}

.dropdown-menu li {
    padding: 0;
}

.dropdown-menu a {
    display: block;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color);
}

.dropdown-menu li:last-child a {
    border-bottom: none;
}

.dropdown-menu a:hover {
    background: var(--bg-light);
    padding-left: 25px;
}

/* Mobile Menu Toggle */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    margin: 3px 0;
    transition: var(--transition);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
    padding: 150px 0 100px;
    margin-top: 70px;
}

.hero-content {
    max-width: 600px;
}

.hero h1 {
    font-size: 52px;
    margin-bottom: 20px;
}

.hero .highlight {
    color: var(--secondary-color);
}

.hero p {
    font-size: 18px;
    margin-bottom: 30px;
}

.hero-buttons {
    display: flex;
    gap: 20px;
}

/* Page Header */
.page-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-white);
    padding: 120px 0 60px;
    text-align: center;
    margin-top: 70px;
}

.page-header h1 {
    font-size: 48px;
    margin-bottom: 15px;
}

.page-header p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 18px;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: var(--bg-white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-card {
    text-align: center;
    padding: 30px;
    background: var(--bg-light);
    border-radius: 10px;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.feature-card i {
    font-size: 48px;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.feature-card h3 {
    margin-bottom: 10px;
}

/* Products Preview */
.products-preview {
    padding: 80px 0;
    background: var(--bg-light);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.product-card {
    background: var(--bg-white);
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.product-card i {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 20px;
}

/* Product Detail Page */
.product-detail {
    padding: 80px 0;
}

.product-detail.alt-bg {
    background: var(--bg-light);
}

.product-detail-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.product-detail-grid.reverse {
    direction: rtl;
}

.product-detail-grid.reverse > * {
    direction: ltr;
}

.product-detail-image img {
    width: 100%;
    border-radius: 10px;
    box-shadow: var(--shadow-md);
}

.product-detail-content h2 {
    color: var(--primary-color);
    margin-bottom: 20px;
}

.product-detail-content h3 {
    margin: 20px 0 10px;
}

.product-detail-content ul {
    list-style: disc;
    padding-left: 20px;
    margin-bottom: 20px;
}

.product-detail-content li {
    margin-bottom: 8px;
    color: var(--text-light);
}

/* Specifications Table */
.specs {
    padding: 80px 0;
    background: var(--bg-light);
}

.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

th {
    background: var(--primary-color);
    color: var(--text-white);
}

tr:hover {
    background: var(--bg-light);
}

/* Contact Page */
.contact-info {
    padding: 60px 0;
}

.contact-info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.contact-card {
    text-align: center;
    padding: 30px;
    background: var(--bg-light);
    border-radius: 10px;
    transition: var(--transition);
}

.contact-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.contact-card i {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

/* Contact Form */
.contact-form-section {
    padding: 80px 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}

.inquiry-form .form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 16px;
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-note {
    font-size: 12px;
    color: var(--text-light);
    margin-top: 15px;
}

.form-message {
    margin-top: 20px;
    padding: 15px;
    border-radius: 5px;
    display: none;
}

.form-message.success {
    display: block;
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.form-message.error {
    display: block;
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* Blog Page */
.blog-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    padding: 60px 0;
}

.blog-card {
    background: var(--bg-white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.blog-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.blog-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.blog-card-content {
    padding: 20px;
}

.category {
    display: inline-block;
    background: var(--secondary-color);
    color: var(--text-white);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    margin-bottom: 12px;
}

.date {
    font-size: 14px;
    color: var(--text-light);
    margin-bottom: 12px;
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 40px 0;
}

.pagination a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    color: var(--text-dark);
}

.pagination a.active,
.pagination a:hover {
    background: var(--primary-color);
    color: var(--text-white);
    border-color: var(--primary-color);
}

/* Newsletter */
.newsletter {
    padding: 60px 0;
    background: var(--bg-light);
    text-align: center;
}

.newsletter-form {
    display: flex;
    justify-content: center;
    gap: 15px;
    max-width: 500px;
    margin: 30px auto 0;
}

.newsletter-form input {
    flex: 1;
    padding: 12px 20px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
}

/* Resource Tabs */
.resource-tabs {
    background: var(--bg-light);
    padding: 20px 0;
    position: sticky;
    top: 70px;
    z-index: 99;
}

.tab-buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 10px 25px;
    background: var(--bg-white);
    border: none;
    border-radius: 30px;
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
}

.tab-btn.active,
.tab-btn:hover {
    background: var(--primary-color);
    color: var(--text-white);
}

.resource-section {
    display: none;
    padding: 60px 0;
}

.resource-section.active {
    display: block;
}

/* FAQ Accordion */
.faq-accordion {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-white);
    border-radius: 10px;
    margin-bottom: 15px;
    box-shadow: var(--shadow-sm);
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    cursor: pointer;
}

.faq-question h3 {
    margin-bottom: 0;
    font-size: 18px;
}

.faq-question i {
    transition: var(--transition);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    display: none;
    padding: 0 20px 20px;
    color: var(--text-light);
    border-top: 1px solid var(--border-color);
}

.faq-item.active .faq-answer {
    display: block;
}

/* Quality & Capability Grids */
.quality-grid,
.capability-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.quality-item,
.capability-card {
    background: var(--bg-white);
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    box-shadow: var(--shadow-sm);
}

.quality-item i,
.capability-card i {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 20px;
}

/* CTA Section */
.cta {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-white);
    text-align: center;
}

.cta h2 {
    margin-bottom: 20px;
}

.cta p {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 30px;
}

.cta .btn-primary {
    background: var(--secondary-color);
}

.cta .btn-primary:hover {
    background: var(--secondary-dark);
}

/* Footer */
footer {
    background: #1a1a2e;
    color: var(--text-white);
    padding: 60px 0 20px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 2fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-about h3 {
    font-size: 24px;
    margin-bottom: 20px;
}

.footer-about span {
    color: var(--secondary-color);
}

.footer-about p {
    color: #aaa;
    margin-bottom: 20px;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: var(--text-white);
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.footer-links h4,
.footer-contact h4 {
    margin-bottom: 20px;
}

.footer-links ul li,
.footer-contact ul li {
    margin-bottom: 10px;
}

.footer-links a {
    color: #aaa;
}

.footer-links a:hover {
    color: var(--secondary-color);
}

.footer-contact i {
    width: 25px;
    color: var(--secondary-color);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #333;
    color: #aaa;
}

/* Back to Top Button */
#back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 45px;
    height: 45px;
    background: var(--primary-color);
    color: var(--text-white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
    display: flex;
    align-items: center;
    justify-content: center;
}

#back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

#back-to-top:hover {
    background: var(--secondary-color);
    transform: translateY(-3px);
}

/* WhatsApp Float Button */
#whatsapp-float {
    position: fixed;
    bottom: 100px;
    right: 30px;
    width: 55px;
    height: 55px;
    background: #25D366;
    color: var(--text-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 30px;
    z-index: 998;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

#whatsapp-float:hover {
    transform: scale(1.1);
}

/* Responsive Design */
@media (max-width: 992px) {
    h1 { font-size: 36px; }
    h2 { font-size: 30px; }
    
    .hero h1 { font-size: 40px; }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    
    .product-detail-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: var(--transition);
        box-shadow: var(--shadow-md);
        padding: 20px 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        box-shadow: none;
        display: none;
        width: 100%;
    }
    
    .dropdown.active .dropdown-menu {
        display: block;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .features-grid,
    .products-grid,
    .blog-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .inquiry-form .form-row {
        grid-template-columns: 1fr;
    }
    
    .newsletter-form {
        flex-direction: column;
    }
    
    .tab-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .page-header h1 {
        font-size: 32px;
    }
}