/* HEATSense Shop - Main Styles - Mobile First */
:root {
    --primary: #1a1a2e;
    --accent: #e94560;
    --accent-light: #ff6b81;
    --bg: #f8f9fa;
    --white: #ffffff;
    --text: #2d3436;
    --text-light: #636e72;
    --glass: rgba(255,255,255,0.85);
    --shadow: 0 8px 32px rgba(0,0,0,0.08);
    --shadow-lg: 0 20px 60px rgba(0,0,0,0.12);
    --success: #00b894;
    --error: #d63031;
    --warning: #fdcb6e;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Inter', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
    width: 100%;
}

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

/* Navigation - Mobile First */
.main-nav {
    position: fixed; top: 0; width: 100%; z-index: 1000;
    background: var(--glass);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
}
.nav-container {
    max-width: 1200px; margin: 0 auto;
    display: flex; justify-content: space-between; align-items: center;
    padding: 1rem;
}
.logo {
    font-size: 1.5rem; font-weight: 800; color: var(--primary);
    text-decoration: none;
}
.logo span { color: var(--accent); }
.nav-links { display: none; list-style: none; }
.nav-links a {
    text-decoration: none; color: var(--text);
    font-weight: 500; font-size: 0.95rem;
    transition: color 0.3s;
}
.nav-links a:hover { color: var(--accent); }

/* Mobile menu toggle */
.mobile-menu-btn {
    display: block;
    background: none; border: none;
    font-size: 1.5rem; cursor: pointer;
    color: var(--primary);
}

/* Main Content */
main { padding-top: 70px; min-height: calc(100vh - 300px); width: 100%; }

/* Hero Section - Mobile First */
.hero {
    padding: 2rem 1rem;
    background: linear-gradient(135deg, var(--primary) 0%, #16213e 100%);
    color: var(--white); text-align: center;
    width: 100%;
}
.hero h1 { font-size: 1.8rem; font-weight: 800; margin-bottom: 1rem; line-height: 1.2; }
.hero h1 span { color: var(--accent-light); }
.hero p { font-size: 1rem; color: rgba(255,255,255,0.7); max-width: 100%; margin: 0 auto 1.5rem; }
.hero .btn { margin-bottom: 0.5rem; }

/* Buttons */
.btn {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.8rem 1.5rem; border-radius: 50px;
    font-weight: 600; font-size: 0.9rem;
    text-decoration: none; transition: all 0.3s;
    cursor: pointer; border: none;
}
.btn-primary {
    background: var(--accent); color: var(--white);
    box-shadow: 0 4px 20px rgba(233,69,96,0.3);
}
.btn-primary:hover { background: var(--accent-light); transform: translateY(-2px); }
.btn-outline {
    border: 2px solid var(--white); color: var(--white); background: transparent;
}
.btn-outline:hover { background: var(--white); color: var(--primary); }
.btn-sm { padding: 0.5rem 1.2rem; font-size: 0.85rem; }
.btn-danger { background: var(--error); color: var(--white); }
.btn-success { background: var(--success); color: var(--white); }

/* Container */
.container {
    max-width: 1200px; margin: 0 auto; padding: 1rem;
    width: 100%;
}

/* Page Header */
.page-header {
    padding: 2rem 1rem; background: var(--white);
    border-bottom: 1px solid rgba(0,0,0,0.05);
}
.page-header h1 { font-size: 1.8rem; font-weight: 800; color: var(--primary); }
.page-header p { color: var(--text-light); margin-top: 0.5rem; }

/* Section Header */
.section-header {
    text-align: center; max-width: 100%; margin: 0 auto 2rem;
    padding: 0 1rem;
}
.section-header h2 {
    font-size: 1.8rem; font-weight: 800; color: var(--primary);
    margin-bottom: 1rem;
}
.section-header p { color: var(--text-light); font-size: 1rem; }

/* Product Grid - Mobile First (1 column default) */
.product-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 1rem 0;
    width: 100%;
}
.product-card {
    background: var(--white); border-radius: 16px;
    overflow: hidden; transition: all 0.4s;
    box-shadow: var(--shadow);
    width: 100%;
}
.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}
.product-image {
    position: relative; padding: 1rem;
    background: var(--bg); display: flex; justify-content: center;
    min-height: 200px; align-items: center;
}
.product-image img {
    max-width: 100%; max-height: 200px; object-fit: contain;
    transition: transform 0.3s;
}
.product-card:hover .product-image img { transform: scale(1.05); }
.product-badge {
    position: absolute; top: 1rem; left: 1rem;
    background: var(--accent); color: var(--white);
    padding: 0.3rem 0.8rem; border-radius: 20px;
    font-size: 0.75rem; font-weight: 600;
}
.product-badge.sale { background: var(--warning); color: var(--primary); }
.product-info { padding: 1.5rem; }
.product-category {
    font-size: 0.8rem; color: var(--accent);
    font-weight: 600; text-transform: uppercase;
    margin-bottom: 0.5rem;
}
.product-name {
    font-size: 1.1rem; font-weight: 700; color: var(--primary);
    margin-bottom: 0.5rem; text-decoration: none; display: block;
}
.product-name:hover { color: var(--accent); }
.product-description {
    font-size: 0.9rem; color: var(--text-light);
    margin-bottom: 1rem; line-height: 1.5;
}
.product-price {
    display: flex; align-items: center; gap: 0.75rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}
.price { font-size: 1.3rem; font-weight: 800; color: var(--primary); }
.old-price { font-size: 1rem; color: var(--text-light); text-decoration: line-through; }
.product-actions { display: flex; gap: 0.5rem; }
.product-actions .btn { flex: 1; justify-content: center; }

/* Product Detail - Mobile First */
.product-detail {
    display: grid; grid-template-columns: 1fr;
    gap: 2rem; padding: 1rem 0;
    width: 100%;
}
.product-detail-image {
    background: var(--white); border-radius: 16px;
    padding: 1.5rem; display: flex; align-items: center; justify-content: center;
}
.product-detail-image img { max-width: 100%; max-height: 300px; }
.product-detail-info h1 { font-size: 1.8rem; font-weight: 800; margin-bottom: 1rem; }
.product-detail-info .price { font-size: 1.8rem; margin-bottom: 1.5rem; }
.product-detail-info .description { color: var(--text-light); margin-bottom: 2rem; line-height: 1.7; }
.product-meta { margin-bottom: 2rem; }
.product-meta-item { display: flex; justify-content: space-between; padding: 0.75rem 0; border-bottom: 1px solid var(--bg); }
.product-meta-item span { color: var(--text-light); }
.quantity-selector { display: flex; align-items: center; gap: 1rem; margin-bottom: 2rem; }
.quantity-selector input {
    width: 60px; padding: 0.5rem; text-align: center;
    border: 1px solid rgba(0,0,0,0.1); border-radius: 8px;
    font-size: 1rem;
}

/* Cart - Mobile First */
.cart-container { max-width: 100%; margin: 0 auto; padding: 1rem; }
.cart-table { 
    width: 100%; 
    border-collapse: collapse; 
    margin-bottom: 2rem;
    font-size: 0.9rem;
}
.cart-table th { 
    text-align: left; 
    padding: 0.75rem; 
    border-bottom: 2px solid var(--bg); 
    font-weight: 600; 
    font-size: 0.85rem;
}
.cart-table td { 
    padding: 0.75rem; 
    border-bottom: 1px solid var(--bg); 
    vertical-align: middle; 
}
.cart-product { display: flex; align-items: center; gap: 0.75rem; }
.cart-product img { width: 60px; height: 60px; object-fit: contain; border-radius: 8px; background: var(--bg); }
.cart-product-info a { font-weight: 600; color: var(--primary); text-decoration: none; font-size: 0.9rem; }
.cart-qty input { width: 50px; padding: 0.3rem; text-align: center; border: 1px solid rgba(0,0,0,0.1); border-radius: 6px; }
.cart-summary { background: var(--white); border-radius: 16px; padding: 1.5rem; }
.cart-summary-row { display: flex; justify-content: space-between; padding: 0.75rem 0; }
.cart-summary-row.total { font-size: 1.2rem; font-weight: 800; border-top: 2px solid var(--bg); margin-top: 0.5rem; padding-top: 1rem; }
.empty-cart { text-align: center; padding: 3rem 1rem; }
.empty-cart h2 { font-size: 1.5rem; margin-bottom: 1rem; }

/* Checkout - Mobile First */
.checkout-grid { display: grid; grid-template-columns: 1fr; gap: 2rem; }
.checkout-form { background: var(--white); border-radius: 16px; padding: 1.5rem; }
.checkout-summary { background: var(--white); border-radius: 16px; padding: 1.5rem; }
.form-group { margin-bottom: 1.25rem; }
.form-group label { display: block; font-size: 0.9rem; font-weight: 500; margin-bottom: 0.5rem; }
.form-group label .required { color: var(--accent); }
.form-group input, .form-group textarea, .form-group select {
    width: 100%; padding: 0.9rem 1rem;
    border: 1px solid rgba(0,0,0,0.1); border-radius: 10px;
    font-size: 1rem; font-family: 'Inter', sans-serif;
    transition: all 0.3s;
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus {
    outline: none; border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(233,69,96,0.1);
}
.form-row { display: grid; grid-template-columns: 1fr; gap: 1rem; }

/* Alerts */
.alert { padding: 1rem 1.5rem; border-radius: 12px; margin-bottom: 1.5rem; }
.alert-success { background: rgba(0,184,148,0.1); border: 1px solid var(--success); color: var(--success); }
.alert-error { background: rgba(214,48,49,0.1); border: 1px solid var(--error); color: var(--error); }
.alert-warning { background: rgba(253,203,110,0.1); border: 1px solid var(--warning); color: #b08d00; }

/* Admin Login */
.admin-login {
    min-height: 100vh; display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, #16213e 100%);
    padding: 1rem;
}
.login-box {
    background: var(--white); border-radius: 24px;
    padding: 2rem; width: 100%; max-width: 420px;
    box-shadow: var(--shadow-lg);
}
.login-box h1 { text-align: center; margin-bottom: 2rem; font-size: 1.5rem; }
.login-box .logo { justify-content: center; margin-bottom: 2rem; display: flex; }

/* Admin Layout - Mobile First */
.admin-layout { display: block; min-height: 100vh; }
.admin-sidebar {
    background: var(--primary); color: var(--white);
    padding: 1.5rem; width: 100%;
}
.admin-sidebar .logo { color: var(--white); margin-bottom: 1.5rem; display: block; font-size: 1.3rem; }
.admin-sidebar .logo span { color: var(--accent-light); }
.admin-nav { list-style: none; display: flex; flex-wrap: wrap; gap: 0.5rem; }
.admin-nav li { margin: 0; }
.admin-nav a {
    display: flex; align-items: center; gap: 0.5rem;
    padding: 0.5rem 0.75rem; border-radius: 8px;
    color: rgba(255,255,255,0.7); text-decoration: none;
    transition: all 0.3s; font-size: 0.85rem;
}
.admin-nav a:hover, .admin-nav a.active {
    background: rgba(255,255,255,0.1); color: var(--white);
}
.admin-main { padding: 1rem; background: var(--bg); min-height: 100vh; width: 100%; }
.admin-header { display: flex; flex-direction: column; gap: 1rem; margin-bottom: 1.5rem; }
.admin-header h1 { font-size: 1.5rem; font-weight: 700; }

/* Stats Cards */
.stats-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; margin-bottom: 1.5rem; }
.stat-card {
    background: var(--white); border-radius: 16px;
    padding: 1.25rem; box-shadow: var(--shadow);
}
.stat-card h3 { font-size: 0.85rem; color: var(--text-light); margin-bottom: 0.5rem; }
.stat-card .value { font-size: 1.5rem; font-weight: 800; color: var(--primary); }
.stat-card .change { font-size: 0.8rem; color: var(--success); margin-top: 0.25rem; }

/* Admin Tables */
.admin-table { 
    width: 100%; 
    background: var(--white); 
    border-radius: 16px; 
    overflow: hidden; 
    box-shadow: var(--shadow);
    font-size: 0.85rem;
}
.admin-table th { background: var(--bg); padding: 0.75rem; text-align: left; font-weight: 600; font-size: 0.8rem; text-transform: uppercase; color: var(--text-light); }
.admin-table td { padding: 0.75rem; border-bottom: 1px solid var(--bg); }
.admin-table tr:last-child td { border-bottom: none; }
.admin-table .actions { display: flex; gap: 0.5rem; }
.admin-table .btn-sm { padding: 0.3rem 0.6rem; font-size: 0.75rem; }
.status-badge {
    display: inline-block; padding: 0.25rem 0.6rem;
    border-radius: 20px; font-size: 0.75rem; font-weight: 600;
}
.status-pending { background: var(--warning); color: #8a6d00; }
.status-processing { background: #74b9ff; color: #0984e3; }
.status-shipped { background: #a29bfe; color: #6c5ce7; }
.status-delivered { background: var(--success); color: #fff; }
.status-cancelled { background: var(--error); color: #fff; }

/* Pagination */
.pagination { display: flex; gap: 0.5rem; justify-content: center; margin-top: 2rem; flex-wrap: wrap; }
.pagination a, .pagination span {
    padding: 0.5rem 1rem; border-radius: 8px;
    text-decoration: none; font-weight: 500;
    transition: all 0.3s;
}
.pagination a { background: var(--white); color: var(--primary); }
.pagination a:hover { background: var(--accent); color: var(--white); }
.pagination span { background: var(--accent); color: var(--white); }

/* Footer */
.main-footer { background: var(--primary); color: rgba(255,255,255,0.6); padding: 2rem 1rem 1rem; }
.footer-container { max-width: 1200px; margin: 0 auto; }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 2rem; margin-bottom: 2rem; }
.footer-col h3, .footer-col h4 { color: var(--white); margin-bottom: 1rem; }
.footer-col h3 span { color: var(--accent-light); }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 0.5rem; }
.footer-col a { color: rgba(255,255,255,0.6); text-decoration: none; transition: color 0.3s; }
.footer-col a:hover { color: var(--accent-light); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 1.5rem; text-align: center; font-size: 0.85rem; }

/* Features Section */
.features {
    padding: 3rem 1rem; background: var(--white);
}
.features-grid {
    max-width: 1200px; margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}
.feature-card {
    background: var(--bg); border-radius: 16px; padding: 1.5rem;
    transition: all 0.4s; position: relative; overflow: hidden;
}
.feature-card::before {
    content: ''; position: absolute; top: 0; left: 0;
    width: 100%; height: 4px; background: var(--accent);
    transform: scaleX(0); transform-origin: left;
    transition: transform 0.4s;
}
.feature-card:hover::before { transform: scaleX(1); }
.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}
.feature-icon {
    width: 48px; height: 48px; border-radius: 12px;
    background: rgba(233,69,96,0.1); color: var(--accent);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.25rem; margin-bottom: 1rem;
}
.feature-card h3 {
    font-size: 1.1rem; font-weight: 700;
    margin-bottom: 0.5rem; color: var(--primary);
}
.feature-card p { color: var(--text-light); line-height: 1.6; font-size: 0.9rem; }

/* Showcase Section */
.showcase {
    padding: 3rem 1rem;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: var(--white); position: relative; overflow: hidden;
}
.showcase-container {
    max-width: 1200px; margin: 0 auto;
    display: grid; grid-template-columns: 1fr;
    gap: 2rem; align-items: center;
}
.showcase-images { display: grid; gap: 1rem; }
.showcase-images img {
    width: 100%; border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}
.showcase-text h2 {
    font-size: 1.8rem; font-weight: 800; margin-bottom: 1rem;
}
.showcase-text h2 span { color: var(--accent-light); }
.showcase-text p {
    font-size: 1rem; color: rgba(255,255,255,0.7);
    line-height: 1.7; margin-bottom: 1.5rem;
}
.specs { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1rem; }
.spec-item {
    background: rgba(255,255,255,0.05); padding: 1rem;
    border-radius: 10px; border: 1px solid rgba(255,255,255,0.08);
}
.spec-item strong {
    display: block; font-size: 1.2rem; color: var(--accent-light);
    margin-bottom: 0.25rem;
}
.spec-item span { font-size: 0.85rem; color: rgba(255,255,255,0.6); }

/* App Section */
.app-section {
    padding: 3rem 1rem; background: var(--bg);
}
.app-container {
    max-width: 1200px; margin: 0 auto;
    display: grid; grid-template-columns: 1fr;
    gap: 2rem; align-items: center;
}
.app-image { position: relative; }
.app-image img {
    width: 100%; border-radius: 16px;
    box-shadow: var(--shadow-lg);
}
.app-text h2 {
    font-size: 1.8rem; font-weight: 800; color: var(--primary);
    margin-bottom: 1rem;
}
.app-text h2 span { color: var(--accent); }
.app-text p {
    font-size: 1rem; color: var(--text-light);
    line-height: 1.7; margin-bottom: 1.5rem;
}
.app-list { list-style: none; }
.app-list li {
    display: flex; align-items: center; gap: 0.75rem;
    padding: 0.5rem 0; font-size: 0.95rem;
    color: var(--text);
}
.app-list li::before {
    content: '✓'; width: 24px; height: 24px;
    border-radius: 50%; background: rgba(233,69,96,0.1);
    color: var(--accent); display: flex; align-items: center;
    justify-content: center; font-size: 0.8rem; font-weight: 700;
    flex-shrink: 0;
}

/* Gallery */
.gallery {
    padding: 2rem 1rem; background: var(--white);
}
.gallery-grid {
    max-width: 1200px; margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
}
.gallery-item {
    border-radius: 12px; overflow: hidden;
    position: relative; cursor: pointer;
    aspect-ratio: 1;
}
.gallery-item img {
    width: 100%; height: 100%; object-fit: cover;
    transition: transform 0.4s;
}
.gallery-item:hover img { transform: scale(1.05); }
.gallery-item::after {
    content: ''; position: absolute; inset: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.6) 0%, transparent 50%);
    opacity: 0; transition: opacity 0.3s;
}
.gallery-item:hover::after { opacity: 1; }
.gallery-item span {
    position: absolute; bottom: 0.5rem; left: 0.5rem;
    color: var(--white); font-weight: 600; font-size: 0.75rem;
    z-index: 2; opacity: 0; transform: translateY(8px);
    transition: all 0.3s;
}
.gallery-item:hover span { opacity: 1; transform: translateY(0); }

/* Contact Section */
.contact {
    padding: 3rem 1rem;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: var(--white); position: relative; overflow: hidden;
}
.contact-container {
    max-width: 800px; margin: 0 auto;
    position: relative; z-index: 1;
}
.contact-header {
    text-align: center; margin-bottom: 2rem;
}
.contact-header h2 {
    font-size: 1.8rem; font-weight: 800; margin-bottom: 1rem;
}
.contact-header h2 span { color: var(--accent-light); }
.contact-header p {
    font-size: 1rem; color: rgba(255,255,255,0.7);
}

/* Contact Form */
.contact-form {
    background: rgba(255,255,255,0.05);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 20px;
    padding: 1.5rem;
}
.contact-form .form-group label {
    color: rgba(255,255,255,0.8);
}
.contact-form .form-group input,
.contact-form .form-group textarea,
.contact-form .form-group select {
    background: rgba(255,255,255,0.05);
    border-color: rgba(255,255,255,0.15);
    color: var(--white);
}
.contact-form .form-group input::placeholder,
.contact-form .form-group textarea::placeholder {
    color: rgba(255,255,255,0.3);
}
.gdpr-group {
    display: flex; align-items: flex-start; gap: 0.75rem;
    margin-bottom: 1.5rem;
}
.gdpr-group input[type="checkbox"] {
    width: 20px; height: 20px;
    border-radius: 6px; border: 2px solid rgba(255,255,255,0.3);
    background: transparent;
    cursor: pointer; accent-color: var(--accent);
    flex-shrink: 0; margin-top: 2px;
}
.gdpr-group label {
    font-size: 0.85rem; color: rgba(255,255,255,0.6);
    line-height: 1.5;
    cursor: pointer;
}
.gdpr-group label a {
    color: var(--accent-light); text-decoration: underline;
}
.btn-cta {
    background: var(--accent); color: var(--white);
    padding: 1rem 2rem; font-size: 1rem;
    box-shadow: 0 8px 30px rgba(233,69,96,0.4);
    width: 100%; justify-content: center;
}
.btn-cta:hover {
    background: var(--accent-light);
    transform: translateY(-3px);
}

/* Hero Badge */
.hero-badge {
    position: absolute; bottom: -15px; left: 10px;
    background: var(--white); padding: 0.75rem 1rem;
    border-radius: 12px; box-shadow: var(--shadow);
    display: flex; align-items: center; gap: 0.5rem;
}
.hero-badge .icon {
    width: 32px; height: 32px; border-radius: 50%;
    background: rgba(233,69,96,0.1);
    display: flex; align-items: center; justify-content: center;
    color: var(--accent); font-size: 1rem;
}
.hero-badge-text { font-size: 0.8rem; }
.hero-badge-text strong { display: block; font-size: 1rem; color: var(--primary); }

/* Hero Image */
.hero-image {
    position: relative; display: flex; justify-content: center;
    margin-top: 2rem;
}
.hero-image img {
    max-width: 100%; border-radius: 16px;
    box-shadow: var(--shadow-lg);
}

/* Specs Section */
.specs-section {
    padding: 3rem 1rem; background: var(--white);
}
.specs-container {
    max-width: 1200px; margin: 0 auto;
    display: grid; grid-template-columns: 1fr;
    gap: 2rem; align-items: start;
}
.specs-image {
    display: flex; align-items: center; justify-content: center;
    padding: 1rem;
}
.specs-image img {
    max-width: 100%; border-radius: 16px;
    filter: drop-shadow(0 10px 20px rgba(0,0,0,0.1));
}
.specs-content h2 {
    font-size: 1.8rem; font-weight: 800; color: var(--primary);
    margin-bottom: 1rem;
}
.specs-content h2 span { color: var(--accent); }
.specs-content > p {
    color: var(--text-light); font-size: 1rem;
    margin-bottom: 1.5rem;
}
.specs-tabs {
    display: flex; gap: 0.5rem; margin-bottom: 1rem;
    border-bottom: 2px solid var(--bg);
    overflow-x: auto;
}
.specs-tab {
    padding: 0.5rem 1rem; cursor: pointer;
    font-weight: 600; color: var(--text-light);
    border-bottom: 3px solid transparent;
    transition: all 0.3s; border-radius: 8px 8px 0 0;
    white-space: nowrap;
    font-size: 0.9rem;
}
.specs-tab:hover { color: var(--accent); background: var(--bg); }
.specs-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}
.specs-panel { display: none; }
.specs-panel.active { display: block; animation: fadeIn 0.4s ease; }
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}
.spec-row {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0.75rem 0; border-bottom: 1px solid var(--bg);
    font-size: 0.9rem;
}
.spec-row span { color: var(--text-light); }
.spec-row strong { color: var(--primary); font-weight: 600; text-align: right; }

/* Tablet (768px+) */
@media (min-width: 768px) {
    .nav-container { padding: 1rem 2rem; }
    .nav-links { display: flex; gap: 2rem; }
    .mobile-menu-btn { display: none; }

    .hero { padding: 4rem 2rem; }
    .hero h1 { font-size: 2.5rem; }
    .hero p { font-size: 1.1rem; }

    .container { padding: 2rem; }
    .page-header { padding: 3rem 2rem; }
    .page-header h1 { font-size: 2.2rem; }

    .product-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
        padding: 2rem 0;
    }
    .product-detail {
        grid-template-columns: 1fr 1fr;
        padding: 2rem 0;
    }
    .product-detail-image img { max-height: 400px; }

    .features { padding: 4rem 2rem; }
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .feature-icon { width: 56px; height: 56px; font-size: 1.5rem; }
    .feature-card h3 { font-size: 1.25rem; }
    .feature-card { padding: 2rem; }

    .showcase { padding: 4rem 2rem; }
    .showcase-text h2 { font-size: 2.2rem; }
    .specs { grid-template-columns: repeat(4, 1fr); }

    .app-section { padding: 4rem 2rem; }
    .app-text h2 { font-size: 2.2rem; }

    .gallery { padding: 3rem 2rem; }
    .gallery-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 1rem;
    }
    .gallery-item span { font-size: 0.85rem; bottom: 0.75rem; left: 0.75rem; }

    .contact { padding: 4rem 2rem; }
    .contact-header h2 { font-size: 2.2rem; }
    .contact-form { padding: 2rem; }
    .btn-cta { width: auto; }

    .specs-section { padding: 4rem 2rem; }
    .specs-container { grid-template-columns: 1fr 1.5fr; }
    .specs-content h2 { font-size: 2.2rem; }

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

    .cart-container { padding: 2rem; }

    .admin-layout { display: grid; grid-template-columns: 260px 1fr; }
    .admin-sidebar {
        position: fixed; width: 260px; height: 100vh;
        padding: 2rem 1.5rem;
    }
    .admin-nav { display: block; }
    .admin-nav li { margin-bottom: 0.5rem; }
    .admin-nav a { padding: 0.75rem 1rem; font-size: 0.95rem; }
    .admin-main { margin-left: 260px; padding: 2rem; }
    .admin-header { flex-direction: row; }
    .admin-header h1 { font-size: 1.8rem; }

    .stats-grid { grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }
    .stat-card { padding: 1.5rem; }
    .stat-card .value { font-size: 2rem; }

    .footer-grid { grid-template-columns: 2fr 1fr 1fr; }

    .login-box { padding: 3rem; }
    .login-box h1 { font-size: 1.8rem; }
}

/* Desktop (1024px+) */
@media (min-width: 1024px) {
    .hero h1 { font-size: 3rem; }
    .hero p { max-width: 600px; }

    .product-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    }

    .features-grid { grid-template-columns: repeat(3, 1fr); }
}