@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ========================================
   CSS Custom Properties
   ======================================== */
:root {
    --color-primary: #6c63ff;
    --color-secondary: #00d4ff;
    --color-accent: #ff6b6b;
    --color-success: #2ecc71;
    --color-warning: #f39c12;
    --color-danger: #e74c3c;
    --color-surface: rgba(255, 255, 255, 0.08);
    --color-surface-hover: rgba(255, 255, 255, 0.14);
    --color-border: rgba(255, 255, 255, 0.12);
    --color-text: #f0f0f0;
    --color-text-muted: rgba(255, 255, 255, 0.6);
    --font-main: 'Inter', sans-serif;
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-full: 50px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.4);
    --shadow-glow-primary: 0 0 20px rgba(108, 99, 255, 0.3);
    --shadow-glow-secondary: 0 0 20px rgba(0, 212, 255, 0.3);
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========================================
   Base & Animated Background
   ======================================== */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    text-align: center;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    background: linear-gradient(-45deg, #0f0c29, #302b63, #24243e, #1a1a2e);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

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

/* ========================================
   Header & Navigation
   ======================================== */
header {
    background: rgba(15, 12, 41, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
    padding: 28px 20px;
    position: sticky;
    top: 0;
    z-index: 100;
    animation: slideDown 0.6s ease-out;
}

@keyframes slideDown {
    from { transform: translateY(-100%); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

header h1 {
    font-size: 2.2rem;
    font-weight: 800;
    margin: 0 0 6px 0;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: 2px;
    text-transform: uppercase;
}

header p {
    color: var(--color-text-muted);
    margin: 0 0 16px 0;
    font-size: 0.95rem;
    font-weight: 300;
}

nav {
    display: flex;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
}

nav a {
    text-decoration: none;
    font-weight: 500;
    color: var(--color-text-muted);
    padding: 8px 18px;
    border-radius: var(--radius-full);
    transition: var(--transition);
    position: relative;
    font-size: 0.9rem;
}

nav a:hover,
nav a.active {
    color: white;
    background: var(--color-surface-hover);
}

nav a.active {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    font-weight: 600;
}

/* ========================================
   Divider
   ======================================== */
hr {
    border: none;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--color-border), transparent);
    margin: 0;
}

/* ========================================
   Search Bar
   ======================================== */
.search-container {
    margin-top: 32px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    padding: 0 20px;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

.search-container label {
    font-weight: 500;
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

.search-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    gap: 10px;
}

input[list] {
    padding: 12px 20px;
    border-radius: var(--radius-full);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    color: white;
    width: 280px;
    font-family: var(--font-main);
    font-size: 0.9rem;
    transition: var(--transition);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

input[list]:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: var(--shadow-glow-primary);
    width: 320px;
}

input[list]::placeholder {
    color: var(--color-text-muted);
}

/* ========================================
   Buttons
   ======================================== */
button {
    background: linear-gradient(135deg, var(--color-primary), #8b5cf6);
    color: white;
    border: none;
    padding: 12px 28px;
    cursor: pointer;
    border-radius: var(--radius-full);
    font-weight: 600;
    font-family: var(--font-main);
    font-size: 0.9rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    letter-spacing: 0.5px;
}

button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: 0.5s;
}

button:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: var(--shadow-glow-primary), var(--shadow-md);
}

button:hover::before {
    left: 100%;
}

button:active {
    transform: translateY(0) scale(0.98);
}

.search-btn {
    padding: 12px 24px;
    background: linear-gradient(135deg, var(--color-secondary), #0099ff);
}

.search-btn:hover {
    box-shadow: var(--shadow-glow-secondary), var(--shadow-md);
}

/* ========================================
   Product Cards
   ======================================== */
main {
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 20px;
}

section h2 {
    color: var(--color-secondary);
    text-decoration: none;
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 32px;
    position: relative;
    display: inline-block;
}

section h2::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    border-radius: 2px;
}

.product-card {
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 32px;
    margin: 24px auto;
    width: 100%;
    max-width: 600px;
    text-align: left;
    transition: var(--transition);
    animation: fadeInUp 0.8s ease-out both;
    position: relative;
    overflow: hidden;
}

.product-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary), var(--color-accent));
    opacity: 0;
    transition: var(--transition);
}

.product-card:hover {
    transform: translateY(-6px);
    border-color: rgba(108, 99, 255, 0.3);
    box-shadow: var(--shadow-lg), var(--shadow-glow-primary);
    background: rgba(255, 255, 255, 0.1);
}

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

.product-card:nth-child(2) {
    animation-delay: 0.15s;
}

.product-card:nth-child(3) {
    animation-delay: 0.3s;
}

.product-card h3 {
    color: var(--color-secondary);
    font-size: 1.3rem;
    font-weight: 700;
    margin: 0 0 16px 0;
}

.product-card figure {
    margin: 0 0 16px 0;
    text-align: center;
}

.product-card img {
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    transition: var(--transition);
    filter: brightness(0.9);
}

.product-card:hover img {
    filter: brightness(1);
    transform: scale(1.03);
}

.product-card figcaption {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin-top: 8px;
}

.product-card p {
    font-size: 1.05rem;
    margin: 12px 0;
}

.product-card p b {
    color: var(--color-text-muted);
    font-weight: 500;
}

/* Price styling */
.product-card p b + span,
.product-card p {
    font-weight: 400;
}

/* ========================================
   Stock Meter
   ======================================== */
.stock-info {
    margin: 16px 0;
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.stock-info label {
    font-weight: 500;
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

meter {
    width: 140px;
    height: 14px;
    border-radius: 7px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--color-border);
}

meter::-webkit-meter-bar {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 7px;
    border: none;
}

meter::-webkit-meter-optimum-value {
    background: linear-gradient(90deg, var(--color-success), #27ae60);
    border-radius: 7px;
}

meter::-webkit-meter-suboptimum-value {
    background: linear-gradient(90deg, var(--color-warning), #e67e22);
    border-radius: 7px;
}

meter::-webkit-meter-even-less-good-value {
    background: linear-gradient(90deg, var(--color-danger), #c0392b);
    border-radius: 7px;
}

meter::-moz-meter-bar {
    background: linear-gradient(90deg, var(--color-success), #27ae60);
    border-radius: 7px;
}

.stock-badge {
    font-size: 0.8rem;
    font-weight: 600;
    padding: 3px 10px;
    border-radius: var(--radius-full);
}

.stock-badge.in-stock {
    color: var(--color-success);
    background: rgba(46, 204, 113, 0.15);
    border: 1px solid rgba(46, 204, 113, 0.3);
}

.stock-badge.low-stock {
    color: var(--color-danger);
    background: rgba(231, 76, 60, 0.15);
    border: 1px solid rgba(231, 76, 60, 0.3);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* ========================================
   Details / Specifications
   ======================================== */
details {
    margin: 16px 0;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: var(--transition);
}

details[open] {
    background: rgba(255, 255, 255, 0.04);
}

summary {
    color: var(--color-primary);
    cursor: pointer;
    font-weight: 600;
    padding: 12px 16px;
    font-size: 0.9rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 8px;
    user-select: none;
}

summary:hover {
    color: var(--color-secondary);
    background: var(--color-surface);
}

summary::before {
    content: '▸';
    transition: transform 0.3s ease;
    display: inline-block;
}

details[open] summary::before {
    transform: rotate(90deg);
}

details ul {
    margin: 0;
    padding: 0 16px 16px 40px;
    list-style: none;
}

details li {
    padding: 6px 0;
    color: var(--color-text-muted);
    font-size: 0.9rem;
    position: relative;
}

details li::before {
    content: '●';
    color: var(--color-secondary);
    position: absolute;
    left: -18px;
    font-size: 0.5rem;
    top: 10px;
}

/* ========================================
   Offer Banner
   ======================================== */
.offer-box {
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    color: var(--color-text);
    padding: 28px;
    width: 100%;
    max-width: 500px;
    margin: 32px auto;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.8s ease-out 0.5s both;
}

.offer-box::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    background: linear-gradient(45deg, var(--color-primary), var(--color-secondary), var(--color-accent), var(--color-primary));
    background-size: 300% 300%;
    border-radius: calc(var(--radius-lg) + 2px);
    z-index: -1;
    animation: borderGradient 4s ease infinite;
}

@keyframes borderGradient {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.offer-box mark {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    padding: 6px 14px;
    border-radius: var(--radius-full);
    font-weight: 700;
    font-size: 0.85rem;
    letter-spacing: 1px;
    display: inline-block;
    margin-bottom: 12px;
}

.offer-box p {
    margin: 0;
    color: var(--color-text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ========================================
   Footer
   ======================================== */
footer {
    background: rgba(15, 12, 41, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid var(--color-border);
    padding: 32px 20px;
    margin-top: 48px;
}

footer label {
    font-weight: 500;
    color: var(--color-text-muted);
    font-size: 0.9rem;
}

progress {
    width: 200px;
    height: 12px;
    margin: 8px;
    border-radius: 6px;
    vertical-align: middle;
}

progress::-webkit-progress-bar {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 6px;
    border: 1px solid var(--color-border);
}

progress::-webkit-progress-value {
    background: linear-gradient(90deg, var(--color-secondary), var(--color-primary));
    border-radius: 6px;
    transition: width 1s ease;
}

progress::-moz-progress-bar {
    background: linear-gradient(90deg, var(--color-secondary), var(--color-primary));
    border-radius: 6px;
}

footer span {
    color: var(--color-secondary);
    font-weight: 600;
    font-size: 0.9rem;
}

footer p {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin: 8px 0 0 0;
}

footer small {
    color: rgba(255, 255, 255, 0.35);
    font-size: 0.8rem;
}

/* ========================================
   Animations
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.6rem;
    }

    nav {
        gap: 6px;
    }

    nav a {
        padding: 6px 12px;
        font-size: 0.8rem;
    }

    .search-container {
        flex-direction: column;
        gap: 10px;
    }

    input[list] {
        width: 100%;
        max-width: 300px;
    }

    input[list]:focus {
        width: 100%;
        max-width: 340px;
    }

    .product-card {
        padding: 24px;
        margin: 16px auto;
    }

    section h2 {
        font-size: 1.4rem;
    }

    .offer-box {
        padding: 20px;
    }

    progress {
        width: 140px;
    }
}

@media (max-width: 480px) {
    header {
        padding: 20px 16px;
    }

    header h1 {
        font-size: 1.3rem;
    }

    main {
        padding: 24px 16px;
    }

    .product-card {
        padding: 20px;
    }

    button {
        padding: 10px 20px;
        font-size: 0.85rem;
    }
}