/* ============================================
   BYOU - Chongqing Boyou Instrument & Meter Co., Ltd.
   Global Stylesheet
   ============================================ */

/* CSS Variables - Theme Colors */
:root {
    /* Primary Colors */
    --primary: #0066FF;
    --primary-dark: #003D99;
    --primary-light: #4D94FF;
    
    /* Neutral Colors */
    --white: #FFFFFF;
    --gray-50: #F5F7FA;
    --gray-100: #E8ECF1;
    --gray-200: #D1D9E6;
    --gray-300: #B0BDCC;
    --gray-400: #8A9BB3;
    --gray-500: #64748B;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1E293B;
    --gray-900: #0F172A;
    
    /* Accent Colors */
    --success: #10B981;
    --warning: #F59E0B;
    --danger: #EF4444;
    
    /* Typography */
    --font-primary: '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;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;
    
    /* Layout */
    --max-width: 1200px;
    --header-height: 80px;
    --border-radius-sm: 4px;
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --border-radius-xl: 16px;
    --border-radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition: 300ms ease;
    --transition-slow: 500ms ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--gray-700);
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul, ol {
    list-style: none;
}

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

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

/* ============================================
   Typography
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

@media (min-width: 768px) {
    h1 { font-size: var(--font-size-5xl); }
    h2 { font-size: var(--font-size-4xl); }
    h3 { font-size: var(--font-size-3xl); }
}

p {
    margin-bottom: var(--spacing-md);
}

.text-primary { color: var(--primary); }
.text-center { text-align: center; }

/* ============================================
   Layout Components
   ============================================ */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.section {
    padding: var(--spacing-4xl) 0;
}

.section-gray {
    background-color: var(--gray-50);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-base);
    font-weight: 600;
    border-radius: var(--border-radius);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

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

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

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

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

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

.btn-white:hover {
    background: var(--gray-50);
    transform: translateY(-2px);
}

.btn-sm {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
}

.btn-lg {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: var(--font-size-lg);
}

/* ============================================
   Header & Navigation
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: var(--white);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: all var(--transition);
}

.header.scrolled {
    box-shadow: var(--shadow);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo img {
    height: 22px;
    width: auto;
}

.logo-text {
    display: none;
}

/* Desktop Navigation */
.nav {
    display: none;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    font-size: var(--font-size-base);
    font-weight: 500;
    color: var(--gray-600);
    padding: var(--spacing-sm) 0;
    position: relative;
}

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

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

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

/* Mobile Menu Toggle */
.menu-toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    padding: var(--spacing-sm);
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* Mobile Navigation */
.mobile-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--white);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
}

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

.mobile-nav-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.mobile-nav-link {
    display: block;
    padding: var(--spacing-md);
    font-size: var(--font-size-lg);
    font-weight: 500;
    color: var(--gray-700);
    border-radius: var(--border-radius);
    transition: all var(--transition-fast);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
    background: var(--gray-50);
    color: var(--primary);
}

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

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 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='0.05'%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");
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: var(--white);
    max-width: 800px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius-full);
    font-size: var(--font-size-sm);
    font-weight: 500;
    margin-bottom: var(--spacing-xl);
    backdrop-filter: blur(10px);
}

.hero-title {
    color: var(--white);
    margin-bottom: var(--spacing-xl);
    line-height: 1.1;
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    opacity: 0.9;
    margin-bottom: var(--spacing-2xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-xl);
    margin-top: var(--spacing-3xl);
    padding-top: var(--spacing-3xl);
    border-top: 1px solid rgba(255, 255, 255, 0.2);
}

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

.hero-stat-number {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    display: block;
}

.hero-stat-label {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

/* ============================================
   Section Headers
   ============================================ */
.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-3xl);
}

.section-header h2 {
    margin-bottom: var(--spacing-md);
}

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

/* ============================================
   Category Cards
   ============================================ */
.categories-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.category-card {
    position: relative;
    background: var(--white);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    text-align: center;
    box-shadow: var(--shadow);
    transition: all var(--transition);
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary);
    transform: scaleX(0);
    transition: transform var(--transition);
}

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

.category-card:hover::before {
    transform: scaleX(1);
}

.category-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-lg);
    background: var(--gray-50);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: var(--primary);
    transition: all var(--transition);
}

.category-image {
    width: 100%;
    height: 160px;
    margin: 0 auto var(--spacing-lg);
    background: var(--gray-50);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.category-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    padding: 8px;
    transition: transform var(--transition);
}

.category-card:hover .category-icon {
    background: var(--primary);
    color: var(--white);
}

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

.category-card h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

.category-card p {
    color: var(--gray-500);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-lg);
}

.category-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--primary);
    font-weight: 600;
    font-size: var(--font-size-sm);
}

.category-link i {
    transition: transform var(--transition-fast);
}

.category-card:hover .category-link i {
    transform: translateX(5px);
}

/* ============================================
   Features / Advantages
   ============================================ */
.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-2xl);
}

.feature-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    color: var(--white);
}

.feature-card h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

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

/* ============================================
   Stats Section
   ============================================ */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-xl);
}

.stat-card {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow);
}

.stat-number {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
    margin-bottom: var(--spacing-sm);
}

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

/* ============================================
   CTA Section
   ============================================ */
.cta-section {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: var(--white);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 60%);
}

.cta-content {
    position: relative;
    z-index: 1;
}

.cta-section h2 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.cta-section p {
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--gray-900);
    color: var(--gray-300);
    padding-top: var(--spacing-4xl);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
    padding-bottom: var(--spacing-3xl);
    border-bottom: 1px solid var(--gray-700);
}

.footer-brand p {
    margin-top: var(--spacing-lg);
    font-size: var(--font-size-sm);
    line-height: 1.8;
}

.footer-column h4 {
    color: var(--white);
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

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

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

.footer-contact li {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-sm);
}

.footer-contact i {
    color: var(--primary-light);
    margin-top: 4px;
}

.footer-bottom {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.footer-bottom p {
    font-size: var(--font-size-sm);
    margin-bottom: 0;
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
}

.social-links a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-800);
    border-radius: var(--border-radius);
    color: var(--gray-400);
    transition: all var(--transition-fast);
}

.social-links a:hover {
    background: var(--primary);
    color: var(--white);
}

/* ============================================
   Page Header (Breadcrumb)
   ============================================ */
.page-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    padding: calc(var(--header-height) + var(--spacing-3xl)) 0 var(--spacing-3xl);
    color: var(--white);
    text-align: center;
}

.page-header h1 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.breadcrumb {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-sm);
    opacity: 0.9;
}

.breadcrumb a:hover {
    opacity: 0.8;
}

.breadcrumb-separator {
    opacity: 0.5;
}

/* ============================================
   Products Grid
   ============================================ */
.products-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
}

.product-card {
    background: var(--white);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all var(--transition);
}

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

.product-image {
    position: relative;
    height: 220px;
    background: var(--gray-100);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    overflow: hidden;
    padding: 12px;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.product-image i {
    font-size: 4rem;
}

.product-badge {
    position: absolute;
    top: var(--spacing-md);
    left: var(--spacing-md);
    background: var(--primary);
    color: var(--white);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--border-radius);
    font-size: var(--font-size-xs);
    font-weight: 600;
}

.product-content {
    padding: var(--spacing-xl);
}

.product-content h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

.product-content p {
    color: var(--gray-500);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-lg);
}

.product-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--gray-100);
}

.product-spec {
    font-size: var(--font-size-sm);
    color: var(--gray-400);
}

/* ============================================
   Large Category Cards (for products.html)
   ============================================ */
.category-large {
    background: var(--white);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    display: grid;
    grid-template-columns: 1fr;
    transition: all var(--transition);
}

.category-large:hover {
    box-shadow: var(--shadow-lg);
}

.category-large-image {
    height: 200px;
    background: linear-gradient(135deg, var(--gray-50) 0%, var(--gray-100) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    overflow: hidden;
}

.category-large-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    padding: 12px;
}

.category-large-image i {
    font-size: 4rem;
}

.category-large-content {
    padding: var(--spacing-xl);
}

.category-large-content h3 {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--spacing-md);
}

.category-large-content p {
    color: var(--gray-500);
    margin-bottom: var(--spacing-lg);
}

.category-large-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    color: var(--gray-400);
    font-size: var(--font-size-sm);
}

.category-large-meta i {
    color: var(--primary);
}

/* ============================================
   About Page Sections
   ============================================ */
.about-intro {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
    align-items: center;
}

.about-image {
    height: 300px;
    background: linear-gradient(135deg, var(--gray-100) 0%, var(--gray-200) 100%);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
}

.about-image i {
    font-size: 5rem;
}

.about-text h2 {
    margin-bottom: var(--spacing-lg);
}

.about-text p {
    color: var(--gray-600);
}

.certifications-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

.certification-item {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--gray-100);
}

.certification-item i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
    display: block;
}

.certification-item h4 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-xs);
}

.certification-item p {
    color: var(--gray-500);
    font-size: var(--font-size-sm);
    margin-bottom: 0;
}

/* ============================================
   Contact Page
   ============================================ */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
}

.contact-form {
    background: var(--white);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
    color: var(--gray-700);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--gray-200);
    border-radius: var(--border-radius);
    background: var(--white);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 102, 255, 0.1);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.form-group.error input,
.form-group.error select,
.form-group.error textarea {
    border-color: var(--danger);
}

.error-message {
    color: var(--danger);
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
    display: none;
}

.form-group.error .error-message {
    display: block;
}

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

.contact-card {
    background: var(--white);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow);
}

.contact-card h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.contact-card h3 i {
    color: var(--primary);
}

.contact-card ul {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.contact-card li {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    color: var(--gray-600);
    font-size: var(--font-size-sm);
}

.contact-card li i {
    color: var(--primary);
    margin-top: 4px;
}

.world-map {
    background: var(--gray-50);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
}

.world-map h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-lg);
}

.regions-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.region-tag {
    background: var(--white);
    border: 1px solid var(--gray-200);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    font-size: var(--font-size-sm);
    color: var(--gray-600);
}

/* ============================================
   Product Detail Page
   ============================================ */
.product-detail {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
}

.product-gallery {
    background: var(--gray-50);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    text-align: center;
}

.product-gallery-image {
    width: 100%;
    min-height: 300px;
    background: var(--white);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    margin-bottom: var(--spacing-lg);
}

.product-gallery-image img {
    max-width: 100%;
    max-height: 400px;
    width: auto;
    height: auto;
    object-fit: contain;
    border-radius: var(--border-radius);
}

.product-gallery-image i {
    font-size: 6rem;
}

.product-thumbnails {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

.product-thumbnail {
    width: 80px;
    height: 80px;
    background: var(--white);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
    overflow: hidden;
    padding: 4px;
}

.product-thumbnail img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.product-thumbnail:hover,
.product-thumbnail.active {
    border-color: var(--primary);
    color: var(--primary);
}

.product-info {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.product-info h1 {
    font-size: var(--font-size-2xl);
}

.product-info .lead {
    color: var(--gray-500);
}

.product-price {
    font-size: var(--font-size-2xl);
    color: var(--primary);
    font-weight: 700;
}

.product-params {
    background: var(--gray-50);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
}

.product-params h4 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-md);
}

.param-item {
    display: flex;
    justify-content: space-between;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--gray-200);
}

.param-item:last-child {
    border-bottom: none;
}

.param-label {
    color: var(--gray-500);
}

.param-value {
    font-weight: 500;
}

.product-actions {
    display: flex;
    gap: var(--spacing-md);
}

/* ============================================
   Application Areas
   ============================================ */
.applications-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.application-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
}

.application-item i {
    width: 40px;
    height: 40px;
    background: var(--gray-50);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
}

.application-item span {
    font-weight: 500;
}

/* ============================================
   Related Products
   ============================================ */
.related-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

/* ============================================
   Scroll Animation
   ============================================ */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease-out;
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Form Success/Error States
   ============================================ */
.form-success {
    display: none;
    text-align: center;
    padding: var(--spacing-2xl);
}

.form-success.show {
    display: block;
}

.form-success i {
    font-size: 4rem;
    color: var(--success);
    margin-bottom: var(--spacing-lg);
}

.form-success h3 {
    color: var(--success);
    margin-bottom: var(--spacing-md);
}

/* ============================================
   Responsive Breakpoints
   ============================================ */

/* Tablet */
@media (min-width: 640px) {
    .hero-stats {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .products-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .hero-buttons {
        flex-direction: row;
        justify-content: center;
    }
}

/* Desktop */
@media (min-width: 1024px) {
    .nav {
        display: block;
    }
    
    .menu-toggle {
        display: none;
    }
    
    .categories-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .about-intro {
        grid-template-columns: 1fr 1fr;
    }
    
    .about-image {
        height: 400px;
    }
    
    .contact-grid {
        grid-template-columns: 1.2fr 1fr;
    }
    
    .product-detail {
        grid-template-columns: 1fr 1fr;
    }
    
    .product-gallery-image {
        min-height: 400px;
    }
    
    .related-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 1.5fr 1fr 1fr 1fr;
    }
    
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

/* Large Desktop */
@media (min-width: 1280px) {
    .container {
        padding: 0 var(--spacing-2xl);
    }
}

/* ============================================
   Utility Classes
   ============================================ */
.hidden { display: none !important; }
.visible { display: block !important; }
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Gap utilities */
.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.gap-xl { gap: var(--spacing-xl); }

/* Margin utilities */
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mb-2xl { margin-bottom: var(--spacing-2xl); }

/* Padding utilities */
.py-lg { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }
.py-xl { padding-top: var(--spacing-xl); padding-bottom: var(--spacing-xl); }
.py-2xl { padding-top: var(--spacing-2xl); padding-bottom: var(--spacing-2xl); }


/* ============================================
   Specifications Table
   ============================================ */
.specs-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: var(--spacing-md);
}

.specs-table th,
.specs-table td {
    padding: var(--spacing-md);
    text-align: left;
    border-bottom: 1px solid var(--gray-200);
}

.specs-table th {
    background-color: var(--gray-50);
    font-weight: 600;
    color: var(--gray-800);
    width: 40%;
}

.specs-table td {
    color: var(--gray-600);
}

.specs-table tr:last-child th,
.specs-table tr:last-child td {
    border-bottom: none;
}

/* ============================================
   Category Image (Applications Grid)
   ============================================ */
.category-image {
    width: 100%;
    height: 160px;
    margin: 0 auto var(--spacing-lg);
    background: var(--gray-50);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.category-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    padding: 8px;
    transition: transform var(--transition);
}

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

/* ============================================
   Application Features List
   ============================================ */
.application-features {
    list-style: none;
    padding: 0;
    margin: var(--spacing-md) 0;
}

.application-features li {
    padding: var(--spacing-xs) 0;
    color: var(--gray-600);
    font-size: var(--font-size-sm);
}

.application-features li i {
    color: var(--primary);
    margin-right: var(--spacing-sm);
    width: 16px;
}

/* ============================================
   Table Responsive
   ============================================ */
.table-responsive {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.table-responsive .specs-table {
    min-width: 600px;
}

/* ============================================
   Placeholder Icon
   ============================================ */
.placeholder-icon {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--gray-100);
    color: var(--gray-400);
    font-size: 4rem;
}