/* ==========================================
   TECHSTORE - E-COMMERCE DEMO
   ========================================== */

:root {
    --primary: #667eea;
    --primary-dark: #5568d3;
    --secondary: #764ba2;
    --success: #4ade80;
    --danger: #ef4444;
    --warning: #fbbf24;
    
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.18);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================
   HEADER
   ========================================== */

.header {
    background: white;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
    gap: 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
}

.logo i {
    color: var(--primary);
}

.logo strong {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s;
}

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

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

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.search-box {
    position: relative;
    display: flex;
    align-items: center;
}

.search-box i {
    position: absolute;
    left: 15px;
    color: var(--text-muted);
}

.search-box input {
    padding: 0.75rem 1rem 0.75rem 2.75rem;
    border: 2px solid var(--border-color);
    border-radius: 50px;
    font-size: 0.95rem;
    width: 280px;
    transition: all 0.3s;
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.cart-btn {
    position: relative;
    background: var(--gradient-primary);
    color: white;
    border: none;
    padding: 0.75rem 1.25rem;
    border-radius: 50px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: transform 0.3s;
}

.cart-btn:hover {
    transform: translateY(-2px);
}

.cart-count {
    position: absolute;
    top: -5px;
    right: -5px;
    background: var(--danger);
    color: white;
    font-size: 0.75rem;
    font-weight: 700;
    padding: 2px 6px;
    border-radius: 50%;
    min-width: 20px;
}

/* ==========================================
   HERO
   ========================================== */

.hero {
    background: var(--gradient-primary);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero-content {
    max-width: 700px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.hero h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    margin-bottom: 1rem;
    font-weight: 800;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
}

.feature-item i {
    font-size: 1.2rem;
}

/* ==========================================
   PRODUCTS
   ========================================== */

.products {
    padding: 4rem 0;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.section-header h2 {
    font-size: 2rem;
    font-weight: 700;
}

.sort-options select {
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    font-size: 0.95rem;
    cursor: pointer;
    background: white;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.product-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    transition: all 0.3s;
    box-shadow: var(--shadow-md);
}

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

.product-image {
    position: relative;
    width: 100%;
    height: 250px;
    overflow: hidden;
    background: var(--bg-tertiary);
}

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

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

.product-badge {
    position: absolute;
    top: 10px;
    right: 10px;
    background: var(--success);
    color: white;
    padding: 5px 12px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
}

.product-content {
    padding: 1.5rem;
}

.product-category {
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: 0.5rem;
}

.product-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.product-description {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.product-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.product-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.btn-add-cart {
    background: var(--gradient-primary);
    color: white;
    border: none;
    padding: 0.75rem 1.25rem;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.3s;
}

.btn-add-cart:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* ==========================================
   CART SIDEBAR
   ========================================== */

.cart-sidebar {
    position: fixed;
    right: -400px;
    top: 0;
    width: 400px;
    height: 100vh;
    background: white;
    box-shadow: var(--shadow-xl);
    z-index: 1000;
    transition: right 0.3s;
    display: flex;
    flex-direction: column;
}

.cart-sidebar.active {
    right: 0;
}

.cart-header {
    padding: 1.5rem;
    border-bottom: 2px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.cart-header h3 {
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.close-cart {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color 0.3s;
}

.close-cart:hover {
    color: var(--danger);
}

.cart-items {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.cart-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    border-radius: 10px;
    background: var(--bg-secondary);
    margin-bottom: 1rem;
}

.cart-item-image {
    width: 80px;
    height: 80px;
    border-radius: 10px;
    object-fit: cover;
}

.cart-item-details {
    flex: 1;
}

.cart-item-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.cart-item-price {
    color: var(--primary);
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.cart-item-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.qty-btn {
    background: var(--primary);
    color: white;
    border: none;
    width: 28px;
    height: 28px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.qty-display {
    min-width: 30px;
    text-align: center;
    font-weight: 600;
}

.cart-item-remove {
    background: none;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 1.1rem;
    padding: 0.25rem;
}

.cart-empty {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted);
}

.cart-empty i {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.3;
}

.cart-footer {
    padding: 1.5rem;
    border-top: 2px solid var(--border-color);
}

.cart-total {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.total-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.btn-checkout {
    width: 100%;
    background: var(--gradient-primary);
    color: white;
    border: none;
    padding: 1rem;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
    transition: all 0.3s;
}

.btn-checkout:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-clear {
    width: 100%;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
    padding: 0.75rem;
    border-radius: 10px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.3s;
}

.btn-clear:hover {
    background: var(--danger);
    color: white;
    border-color: var(--danger);
}

.cart-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}

.cart-overlay.active {
    opacity: 1;
    pointer-events: all;
}

/* ==========================================
   MODAL
   ========================================== */

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}

.modal.active {
    opacity: 1;
    pointer-events: all;
}

.modal-content {
    background: white;
    border-radius: 20px;
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    z-index: 1;
}

.modal-header {
    text-align: center;
    padding: 2rem 2rem 1rem;
}

.modal-header i {
    font-size: 4rem;
    color: var(--success);
    margin-bottom: 1rem;
}

.modal-header h2 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
}

.modal-body {
    padding: 0 2rem 1rem;
}

.modal-body p {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.checkout-summary {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 10px;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.75rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.summary-item:last-child {
    border-bottom: none;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--primary);
}

.modal-footer {
    padding: 1rem 2rem 2rem;
}

.btn-primary {
    width: 100%;
    background: var(--gradient-primary);
    color: white;
    border: none;
    padding: 1rem;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

/* ==========================================
   FOOTER
   ========================================== */

.footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-col h4 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.footer-col p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 1rem;
}

.footer-col ul {
    list-style: none;
}

.footer-col ul li {
    margin-bottom: 0.5rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-col ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-col ul li a:hover {
    color: white;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s;
}

.social-links a:hover {
    background: var(--primary);
    transform: translateY(-3px);
}

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.7);
}

.back-to-portfolio {
    color: white;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50px;
    transition: all 0.3s;
}

.back-to-portfolio:hover {
    background: var(--primary);
}

/* ==========================================
   RESPONSIVE
   ========================================== */

@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .search-box input {
        width: 180px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-features {
        flex-direction: column;
        align-items: center;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 1.5rem;
    }
    
    .cart-sidebar {
        width: 100%;
        right: -100%;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
}