/* ========================================
   Yonggu Intelligent - SMT Equipment Website
   Style Sheet
   ======================================== */

/* CSS Variables */
:root {
    /* Primary Colors - Navy Blue */
    --color-primary: #1a365d;
    --color-primary-dark: #0f2744;
    --color-primary-light: #2c5282;
    
    /* Accent Colors - Orange */
    --color-accent: #ed8936;
    --color-accent-dark: #dd6b20;
    --color-accent-light: #f6ad55;
    
    /* Neutral Colors */
    --color-white: #ffffff;
    --color-gray-50: #f7fafc;
    --color-gray-100: #edf2f7;
    --color-gray-200: #e2e8f0;
    --color-gray-300: #cbd5e0;
    --color-gray-400: #a0aec0;
    --color-gray-500: #718096;
    --color-gray-600: #4a5568;
    --color-gray-700: #2d3748;
    --color-gray-800: #1a202c;
    --color-gray-900: #171923;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    
    /* Font Weights */
    --font-light: 300;
    --font-normal: 400;
    --font-medium: 500;
    --font-semibold: 600;
    --font-bold: 700;
    
    /* Line Heights */
    --leading-tight: 1.25;
    --leading-snug: 1.375;
    --leading-normal: 1.5;
    --leading-relaxed: 1.625;
    --leading-loose: 2;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    
    /* Container */
    --container-max: 1280px;
    --container-padding: 1.5rem;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--leading-normal);
    color: var(--color-gray-700);
    background-color: var(--color-white);
}

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

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

ul, ol {
    list-style: none;
}

input, textarea, select {
    font-family: inherit;
    font-size: inherit;
}

/* Container */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* ========================================
   Header
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: var(--color-primary);
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.logo-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    font-weight: var(--font-bold);
    font-size: var(--font-size-lg);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-name {
    color: var(--color-white);
    font-weight: var(--font-semibold);
    font-size: var(--font-size-lg);
    line-height: var(--leading-tight);
}

.logo-subtitle {
    color: var(--color-gray-300);
    font-size: var(--font-size-xs);
    letter-spacing: 0.05em;
}

.logo-img {
    height: 40px;
    width: auto;
    max-width: 160px;
    object-fit: contain;
    background-color: var(--color-white);
    border-radius: var(--radius-md);
    padding: 4px;
}

/* Navigation */
.nav-list {
    display: flex;
    align-items: center;
    gap: var(--space-8);
}

.nav-link {
    color: var(--color-gray-300);
    font-weight: var(--font-medium);
    font-size: var(--font-size-sm);
    padding: var(--space-2) 0;
    position: relative;
    transition: var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-accent);
    transition: var(--transition-base);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-white);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Header Actions */
.header-actions {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

.lang-switch {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-gray-300);
    font-size: var(--font-size-sm);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
}

.lang-switch:hover {
    color: var(--color-white);
    background-color: rgba(255, 255, 255, 0.1);
}

.lang-current {
    color: var(--color-white);
    font-weight: var(--font-medium);
}

.lang-separator {
    color: var(--color-gray-500);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    font-weight: var(--font-medium);
    font-size: var(--font-size-sm);
    border-radius: var(--radius-md);
    transition: var(--transition-base);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
    color: var(--color-white);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--color-accent-dark) 0%, #c05621 100%);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-outline {
    background-color: transparent;
    color: var(--color-white);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-outline:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: var(--color-white);
}

.btn-lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--font-size-base);
}

.btn-block {
    width: 100%;
}

.btn-sm {
    padding: var(--space-2) var(--space-4);
    font-size: var(--font-size-sm);
}

.icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: var(--space-2);
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-white);
    transition: var(--transition-base);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(237, 137, 54, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(237, 137, 54, 0.1) 0%, transparent 40%),
        radial-gradient(circle at 60% 80%, rgba(44, 82, 130, 0.3) 0%, transparent 50%);
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 700px;
    padding-top: 72px;
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: var(--font-bold);
    color: var(--color-white);
    line-height: var(--leading-tight);
    margin-bottom: var(--space-6);
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-medium);
    color: var(--color-accent-light);
    margin-bottom: var(--space-4);
}

.hero-desc {
    font-size: var(--font-size-lg);
    color: var(--color-gray-300);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-8);
    max-width: 560px;
}

.hero-actions {
    display: flex;
    gap: var(--space-4);
    flex-wrap: wrap;
}

.hero-scroll {
    position: absolute;
    bottom: var(--space-8);
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
}

.scroll-indicator {
    width: 24px;
    height: 40px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: var(--radius-full);
    display: flex;
    justify-content: center;
    padding-top: var(--space-2);
}

.scroll-indicator span {
    width: 4px;
    height: 8px;
    background-color: var(--color-accent);
    border-radius: var(--radius-full);
    animation: scrollBounce 2s infinite;
}

@keyframes scrollBounce {
    0%, 100% { transform: translateY(0); opacity: 1; }
    50% { transform: translateY(8px); opacity: 0.5; }
}

/* ========================================
   Features Section
   ======================================== */
.features {
    background-color: var(--color-white);
    padding: var(--space-16) 0;
    border-bottom: 1px solid var(--color-gray-100);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-8);
}

.feature-item {
    text-align: center;
    padding: var(--space-6);
}

.feature-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-5);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
}

.feature-icon svg {
    width: 32px;
    height: 32px;
}

.feature-item h3 {
    font-size: var(--font-size-lg);
    font-weight: var(--font-semibold);
    color: var(--color-gray-800);
    margin-bottom: var(--space-2);
}

.feature-item p {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* ========================================
   Section Headers
   ======================================== */
.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--space-12);
}

.section-tag {
    display: inline-block;
    font-size: var(--font-size-sm);
    font-weight: var(--font-semibold);
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-3);
}

.section-title {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-bold);
    color: var(--color-gray-800);
    margin-bottom: var(--space-4);
}

.section-desc {
    font-size: var(--font-size-lg);
    color: var(--color-gray-500);
}

/* ========================================
   Products Section
   ======================================== */
.products {
    padding: var(--space-24) 0;
    background-color: var(--color-gray-50);
}

/* Product Categories */
.product-categories {
    display: flex;
    justify-content: center;
    gap: var(--space-3);
    margin-bottom: var(--space-10);
    flex-wrap: wrap;
}

.category-btn {
    padding: var(--space-3) var(--space-6);
    font-size: var(--font-size-sm);
    font-weight: var(--font-medium);
    color: var(--color-gray-600);
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-full);
    transition: var(--transition-base);
}

.category-btn:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.category-btn.active {
    color: var(--color-white);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    border-color: var(--color-primary);
}

/* Products Grid */
.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
}

.product-card {
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-base);
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.product-image {
    position: relative;
    aspect-ratio: 4/3;
    background: linear-gradient(135deg, var(--color-gray-100) 0%, var(--color-gray-200) 100%);
    overflow: hidden;
}

.product-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-base);
}

.product-card:hover .product-img {
    transform: scale(1.05);
}

.product-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-6);
    color: var(--color-gray-400);
}

.product-placeholder svg {
    width: 100%;
    height: 100%;
    max-width: 160px;
}

.product-overlay {
    position: absolute;
    inset: 0;
    background-color: rgba(26, 54, 93, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition-base);
}

.product-card:hover .product-overlay {
    opacity: 1;
}

.btn-view {
    padding: var(--space-3) var(--space-6);
    background-color: var(--color-accent);
    color: var(--color-white);
    font-weight: var(--font-medium);
    font-size: var(--font-size-sm);
    border-radius: var(--radius-md);
    transform: translateY(10px);
    transition: var(--transition-base);
}

.product-card:hover .btn-view {
    transform: translateY(0);
}

.btn-view:hover {
    background-color: var(--color-accent-dark);
}

.product-info {
    padding: var(--space-5);
}

.product-name {
    font-size: var(--font-size-lg);
    font-weight: var(--font-semibold);
    color: var(--color-gray-800);
    margin-bottom: var(--space-2);
}

.product-desc {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
    margin-bottom: var(--space-3);
    line-height: var(--leading-relaxed);
}

.product-tags {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
}

.tag {
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: var(--font-medium);
    color: var(--color-primary);
    background-color: rgba(26, 54, 93, 0.08);
    border-radius: var(--radius-full);
}

/* ========================================
   About Section
   ======================================== */
.about {
    padding: var(--space-24) 0;
    background-color: var(--color-white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
}

.about-content .section-tag {
    margin-bottom: var(--space-4);
}

.about-content .section-title {
    text-align: left;
    margin-bottom: var(--space-6);
}

.about-text {
    font-size: var(--font-size-base);
    color: var(--color-gray-600);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-4);
}

.about-stats {
    display: flex;
    gap: var(--space-10);
    margin-top: var(--space-8);
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-gray-200);
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: var(--font-size-3xl);
    font-weight: var(--font-bold);
    color: var(--color-primary);
    line-height: var(--leading-tight);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

.about-visual {
    position: relative;
    aspect-ratio: 4/3;
}

.visual-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    border-radius: var(--radius-2xl);
    transform: rotate(-3deg);
}

.visual-content {
    position: relative;
    width: 100%;
    height: 100%;
    background-color: var(--color-white);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-8);
    color: var(--color-primary);
}

.visual-content svg {
    width: 100%;
    height: auto;
    max-width: 280px;
}

/* ========================================
   Contact Section
   ======================================== */
.contact {
    padding: var(--space-24) 0;
    background-color: var(--color-gray-50);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: var(--space-12);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
}

.contact-card {
    display: flex;
    align-items: flex-start;
    gap: var(--space-4);
    padding: var(--space-6);
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-base);
}

.contact-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(4px);
}

.contact-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    flex-shrink: 0;
}

.contact-icon svg {
    width: 24px;
    height: 24px;
}

.contact-details h3 {
    font-size: var(--font-size-base);
    font-weight: var(--font-semibold);
    color: var(--color-gray-800);
    margin-bottom: var(--space-1);
}

.contact-link {
    font-size: var(--font-size-lg);
    font-weight: var(--font-semibold);
    color: var(--color-primary);
    display: block;
    margin-bottom: var(--space-1);
    transition: var(--transition-fast);
}

.contact-link:hover {
    color: var(--color-accent);
}

.contact-details p:last-child {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* Contact Form */
.contact-form-wrapper {
    background-color: var(--color-white);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    box-shadow: var(--shadow-lg);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-5);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-5);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.form-group label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-medium);
    color: var(--color-gray-700);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-md);
    background-color: var(--color-white);
    color: var(--color-gray-800);
    transition: var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(26, 54, 93, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background-color: var(--color-gray-800);
    color: var(--color-gray-300);
    padding-top: var(--space-16);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: var(--space-10);
    padding-bottom: var(--space-12);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .logo {
    margin-bottom: var(--space-4);
}

.footer-desc {
    font-size: var(--font-size-sm);
    line-height: var(--leading-relaxed);
    max-width: 280px;
}

.footer-links h4,
.footer-contact h4 {
    font-size: var(--font-size-base);
    font-weight: var(--font-semibold);
    color: var(--color-white);
    margin-bottom: var(--space-4);
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.footer-links a {
    font-size: var(--font-size-sm);
    color: var(--color-gray-400);
    transition: var(--transition-fast);
}

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

.footer-contact p {
    font-size: var(--font-size-sm);
    margin-bottom: var(--space-2);
}

.footer-contact strong {
    color: var(--color-gray-400);
    font-weight: var(--font-normal);
}

.footer-contact a {
    color: var(--color-gray-300);
    transition: var(--transition-fast);
}

.footer-contact a:hover {
    color: var(--color-accent);
}

.footer-bottom {
    padding: var(--space-6) 0;
    text-align: center;
}

.footer-bottom p {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1200px) {
    .products-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 992px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: var(--font-size-4xl);
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .products-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .about-grid {
        grid-template-columns: 1fr;
        gap: var(--space-10);
    }
    
    .about-image {
        order: -1;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --container-padding: 1rem;
    }
    
    .header-actions .btn-primary {
        display: none;
    }
    
    .hero-title {
        font-size: var(--font-size-3xl);
    }
    
    .hero-subtitle {
        font-size: var(--font-size-xl);
    }
    
    .features-grid {
        grid-template-columns: 1fr;
        gap: var(--space-4);
    }
    
    .feature-item {
        display: flex;
        align-items: center;
        text-align: left;
        gap: var(--space-4);
        padding: var(--space-4);
    }
    
    .feature-icon {
        margin: 0;
        flex-shrink: 0;
    }
    
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .product-categories {
        gap: var(--space-2);
    }
    
    .category-btn {
        padding: var(--space-2) var(--space-4);
        font-size: var(--font-size-xs);
    }
    
    .about-stats {
        gap: var(--space-6);
    }
    
    .stat-number {
        font-size: var(--font-size-2xl);
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }
}

@media (max-width: 480px) {
    .hero-actions {
        flex-direction: column;
    }
    
    .btn-lg {
        width: 100%;
    }
    
    .about-stats {
        flex-direction: column;
        gap: var(--space-4);
    }
    
    .stat-item {
        text-align: left;
        display: flex;
        align-items: center;
        gap: var(--space-3);
    }
}

/* ========================================
   Animations
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.product-card {
    animation: fadeInUp 0.5s ease forwards;
}

.product-card:nth-child(1) { animation-delay: 0.1s; }
.product-card:nth-child(2) { animation-delay: 0.15s; }
.product-card:nth-child(3) { animation-delay: 0.2s; }
.product-card:nth-child(4) { animation-delay: 0.25s; }
.product-card:nth-child(5) { animation-delay: 0.3s; }
.product-card:nth-child(6) { animation-delay: 0.35s; }
.product-card:nth-child(7) { animation-delay: 0.4s; }
.product-card:nth-child(8) { animation-delay: 0.45s; }

/* Utility Classes */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* ========================================
   企业微信客服浮动按钮
   ======================================== */
.wechat-float {
    position: fixed;
    right: 24px;
    bottom: 48px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.wechat-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, #07c160, #06ad56);
    color: #fff;
    border: none;
    border-radius: 50%;
    box-shadow: 0 4px 16px rgba(7, 193, 96, 0.45);
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    padding: 0;
    text-decoration: none;
}

.wechat-btn:hover {
    transform: scale(1.08) translateY(-2px);
    box-shadow: 0 8px 24px rgba(7, 193, 96, 0.55);
}

/* WhatsApp 按钮专属颜色 */
.wechat-btn-en {
    background: linear-gradient(135deg, #25d366, #1da851);
    box-shadow: 0 4px 16px rgba(37, 211, 102, 0.45);
}

.wechat-btn-en:hover {
    box-shadow: 0 8px 24px rgba(37, 211, 102, 0.58);
}

.wechat-label {
    font-size: 9px;
    font-weight: 600;
    letter-spacing: 0.5px;
    line-height: 1;
}

.wechat-popup {
    position: absolute;
    bottom: 76px;
    right: 0;
    width: 220px;
    background: #fff;
    border-radius: 14px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.16), 0 2px 8px rgba(0, 0, 0, 0.08);
    overflow: hidden;
    opacity: 0;
    transform: translateY(12px) scale(0.95);
    pointer-events: none;
    transition: opacity 0.22s ease, transform 0.22s ease;
    transform-origin: bottom right;
}

.wechat-popup.active {
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: auto;
}

.wechat-popup-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 14px 10px;
    background: linear-gradient(135deg, #07c160, #06ad56);
    color: #fff;
    font-size: 13px;
    font-weight: 600;
}

.wechat-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    border-radius: 50%;
    color: #fff;
    cursor: pointer;
    transition: background 0.2s;
    padding: 0;
}

.wechat-close:hover {
    background: rgba(255, 255, 255, 0.35);
}

.wechat-popup-body {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 16px 14px 18px;
    gap: 6px;
}

.wechat-qr {
    width: 160px;
    height: 160px;
    object-fit: contain;
    border-radius: 8px;
    border: 1px solid #f0f0f0;
    display: block;
}

.wechat-name {
    font-size: 15px;
    font-weight: 700;
    color: #1a202c;
    margin: 4px 0 0;
}

.wechat-company {
    font-size: 12px;
    color: #718096;
    margin: 0;
}

/* ========================================
   Blog Section Styles
   ======================================== */

.blog-section {
    padding: 80px 0;
    background: #f8fafc;
}

.blog-preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.blog-preview-card {
    background: #fff;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.blog-preview-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0,0,0,0.1);
}

.blog-preview-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.blog-preview-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.blog-preview-card:hover .blog-preview-image img {
    transform: scale(1.05);
}

.blog-preview-tag {
    position: absolute;
    top: 16px;
    left: 16px;
    padding: 6px 14px;
    background: #3b82f6;
    color: #fff;
    font-size: 12px;
    font-weight: 600;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.blog-preview-content {
    padding: 24px;
}

.blog-preview-meta {
    display: flex;
    gap: 16px;
    margin-bottom: 12px;
    font-size: 13px;
    color: #64748b;
}

.blog-preview-content h3 {
    font-size: 18px;
    font-weight: 600;
    color: #0f172a;
    margin-bottom: 12px;
    line-height: 1.4;
}

.blog-preview-content p {
    font-size: 14px;
    color: #64748b;
    line-height: 1.6;
    margin-bottom: 16px;
}

.blog-view-all {
    text-align: center;
    margin-top: 48px;
}

/* ========================================
   Social Links Styles
   ======================================== */

.social-links {
    display: flex;
    gap: 12px;
    margin-top: 20px;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: #94a3b8;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: #3b82f6;
    color: #fff;
    transform: translateY(-2px);
}

.social-link svg {
    width: 20px;
    height: 20px;
}

.wechat-tip {
    font-size: 11px;
    color: #a0aec0;
    text-align: center;
    margin: 4px 0 0;
    line-height: 1.5;
}

@media (max-width: 480px) {
    .wechat-float {
        right: 14px;
        bottom: 32px;
    }
    .wechat-btn {
        width: 56px;
        height: 56px;
    }
    .wechat-popup {
        width: 195px;
    }
    .wechat-qr {
        width: 140px;
        height: 140px;
    }
}