/* ==========================================================================
   CSS VARIABLES - RICH RED PALETTE & DESIGN TOKENS
   ========================================================================== */
   :root {
    /* Color Palette: Deep, elegant reds */
    --c-primary-50: #fff5f5;
    --c-primary-100: #fee2e2;
    --c-primary-200: #fecaca;
    --c-primary-300: #fca5a5;
    --c-primary-400: #f87171;
    --c-primary-500: #ef4444; /* Core Brand Red */
    --c-primary-600: #dc2626;
    --c-primary-700: #b91c1c;
    --c-primary-800: #991b1b;
    --c-primary-900: #7f1d1d;
    --c-primary-950: #450a0a;

    /* Neutrals */
    --c-bg-main: #fcfaf9;
    --c-surface: #ffffff;
    --c-text-main: #1f2937;
    --c-text-muted: #6b7280;
    --c-text-light: #9ca3af;
    --c-border: #f3f4f6;
    
    /* Stars / Accents */
    --c-accent-gold: #f59e0b;
    --c-success: #059669;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.05), 0 2px 4px -2px rgb(0 0 0 / 0.05);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.05), 0 4px 6px -4px rgb(0 0 0 / 0.05);
    --shadow-xl: 0 20px 25px -5px rgb(153 27 27 / 0.1), 0 8px 10px -6px rgb(153 27 27 / 0.1);
    --shadow-glow: 0 0 30px 0 rgb(239 68 68 / 0.15);
    --shadow-inner: inset 0 2px 4px 0 rgb(0 0 0 / 0.05);

    /* Gradients */
    --grad-primary: linear-gradient(135deg, var(--c-primary-500) 0%, var(--c-primary-700) 100%);
    --grad-surface: linear-gradient(180deg, rgba(255,255,255,1) 0%, rgba(255,255,255,0.95) 100%);
    --grad-blob: radial-gradient(circle, var(--c-primary-200) 0%, rgba(254,226,226,0) 70%);

    /* Typography */
    --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    
    /* Layout */
    --radius-md: 0.75rem;
    --radius-lg: 1.25rem;
    --radius-xl: 2rem;
    --transition-fast: 0.15s ease-in-out;
    --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    --transition-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ==========================================================================
   RESET & BASE STYLES
   ========================================================================== */
html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background-color: var(--c-bg-main);
    color: var(--c-text-main);
    position: relative;
    overflow-x: hidden;
    line-height: 1.6;
}

::selection {
    background: var(--c-primary-200);
    color: var(--c-primary-900);
}

/* ==========================================================================
   DECORATIVE BACKGROUNDS (Blobs & Noise)
   ========================================================================== */
.bg-decorative {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.5;
    animation: blob-float 20s infinite alternate;
}

.blob-1 {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: var(--grad-blob);
}

.blob-2 {
    bottom: -20%;
    right: -10%;
    width: 60vw;
    height: 60vw;
    background: radial-gradient(circle, var(--c-primary-100) 0%, rgba(254,226,226,0) 70%);
    animation-delay: -5s;
    animation-duration: 25s;
}

.blob-3 {
    top: 40%;
    left: 50%;
    transform: translateX(-50%);
    width: 40vw;
    height: 40vw;
    background: radial-gradient(circle, var(--c-primary-50) 0%, rgba(255,245,245,0) 70%);
    animation-delay: -10s;
}

.noise-overlay {
    position: absolute;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.02'/%3E%3C/svg%3E");
    opacity: 0.4;
    mix-blend-mode: overlay;
}

@keyframes blob-float {
    0% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -50px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
    100% { transform: translate(0, 0) scale(1); }
}

/* Glassmorphism Panel Utility */
.glass-panel {
    background: var(--grad-surface);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.6);
    box-shadow: var(--shadow-xl), var(--shadow-glow);
    border-radius: var(--radius-xl);
}

/* ==========================================================================
   HEADER
   ========================================================================== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--c-primary-100);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-smooth);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4.5rem;
}

.header-empty, .header-secure {
    flex: 1;
    display: flex;
    align-items: center;
}

.header-secure {
    justify-content: flex-end;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--c-primary-700);
    gap: 0.5rem;
}

.secure-icon {
    width: 1.25rem;
    height: 1.25rem;
    color: var(--c-primary-500);
}

.premium-badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    background: var(--c-primary-50);
    color: var(--c-primary-800);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-radius: 9999px;
    border: 1px solid var(--c-primary-200);
}

.header-title-wrapper {
    flex: 2;
    text-center: center;
    display: flex;
    justify-content: center;
}

.header-title {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--c-primary-900);
    letter-spacing: -0.025em;
    position: relative;
}

.header-title::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 20%;
    width: 60%;
    height: 2px;
    background: var(--grad-primary);
    border-radius: 2px;
    opacity: 0;
    transition: var(--transition-smooth);
}

.site-header:hover .header-title::after {
    opacity: 1;
    width: 100%;
    left: 0;
}

/* ==========================================================================
   PRODUCT HERO SECTION
   ========================================================================== */
.product-hero {
    padding: 3rem 0;
    perspective: 1000px;
}

.product-card {
    padding: 2.5rem;
    position: relative;
    overflow: hidden;
    animation: fade-in-up 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Subtle corner glow in product card */
.product-card::before {
    content: '';
    position: absolute;
    top: -50px;
    left: -50px;
    width: 150px;
    height: 150px;
    background: radial-gradient(circle, var(--c-primary-100) 0%, transparent 70%);
    border-radius: 50%;
    opacity: 0.6;
    z-index: 0;
    pointer-events: none;
}

.product-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    position: relative;
    z-index: 1;
}

/* ==========================================================================
   CSS-ONLY GALLERY
   ========================================================================== */
.product-gallery {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.main-image-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 1 / 1;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: inset 0 0 0 1px rgba(0,0,0,0.05), var(--shadow-md);
    background-color: #fff;
}

.image-showcase {
    position: absolute;
    inset: 0;
    opacity: 0;
    transform: scale(0.95);
    transition: opacity 0.5s ease, transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1;
}

.image-showcase img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

.image-glow {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center, transparent 40%, rgba(0,0,0,0.03) 100%);
    pointer-events: none;
    mix-blend-mode: multiply;
}

/* Gallery Logic (The Magic) */
#img-1:checked ~ .main-image-wrapper #showcase-1,
#img-2:checked ~ .main-image-wrapper #showcase-2,
#img-3:checked ~ .main-image-wrapper #showcase-3,
#img-4:checked ~ .main-image-wrapper #showcase-4 {
    opacity: 1;
    transform: scale(1);
    z-index: 2;
}

.thumbnails-wrapper {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
}

.thumbnail-item {
    position: relative;
    aspect-ratio: 1 / 1;
    border-radius: var(--radius-md);
    overflow: hidden;
    cursor: pointer;
    background: #fff;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-smooth);
}

.thumbnail-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.thumb-border {
    position: absolute;
    inset: 0;
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
    z-index: 10;
}

.thumbnail-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.thumbnail-item:hover img {
    transform: scale(1.05);
}

/* Active Thumbnail Logic */
#img-1:checked ~ .thumbnails-wrapper label[for="img-1"] .thumb-border,
#img-2:checked ~ .thumbnails-wrapper label[for="img-2"] .thumb-border,
#img-3:checked ~ .thumbnails-wrapper label[for="img-3"] .thumb-border,
#img-4:checked ~ .thumbnails-wrapper label[for="img-4"] .thumb-border {
    border-color: var(--c-primary-500);
    box-shadow: inset 0 0 0 2px var(--c-primary-50);
}

#img-1:checked ~ .thumbnails-wrapper label[for="img-1"],
#img-2:checked ~ .thumbnails-wrapper label[for="img-2"],
#img-3:checked ~ .thumbnails-wrapper label[for="img-3"],
#img-4:checked ~ .thumbnails-wrapper label[for="img-4"] {
    opacity: 0.8;
}

/* ==========================================================================
   PRODUCT INFORMATION
   ========================================================================== */
.product-info {
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.product-title {
    font-size: 2.5rem;
    font-weight: 800;
    line-height: 1.1;
    color: var(--c-text-main);
    margin-bottom: 1rem;
    letter-spacing: -0.03em;
}

.amazon-rating {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.stars {
    display: flex;
    color: var(--c-accent-gold);
}

.star {
    width: 1.25rem;
    height: 1.25rem;
}

.rating-text {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--c-text-muted);
}

.divider {
    height: 1px;
    background: linear-gradient(to right, var(--c-primary-100), transparent);
    margin: 1.5rem 0;
}

.section-subtitle {
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--c-primary-600);
    margin-bottom: 1rem;
}

.feature-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    font-size: 1rem;
    color: var(--c-text-main);
    line-height: 1.5;
}

.check-icon {
    flex-shrink: 0;
    width: 1.25rem;
    height: 1.25rem;
    margin-top: 0.125rem;
    background-color: var(--c-primary-100);
    border-radius: 50%;
    position: relative;
    color: var(--c-primary-600);
}

.check-icon::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0.35rem;
    height: 0.6rem;
    border: solid currentColor;
    border-width: 0 2px 2px 0;
    transform: translate(-50%, -60%) rotate(45deg);
}

/* SEO Block */
.seo-safe-box {
    margin-top: 2rem;
    padding: 1.25rem;
    background: linear-gradient(to right, var(--c-primary-50), transparent);
    border-left: 4px solid var(--c-primary-400);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    display: flex;
    gap: 1rem;
    align-items: flex-start;
}

.seo-icon-wrap {
    color: var(--c-primary-500);
    width: 1.5rem;
    height: 1.5rem;
    flex-shrink: 0;
    margin-top: 0.125rem;
}

.seo-text {
    font-size: 0.875rem;
    color: var(--c-primary-900);
    line-height: 1.6;
}

.product-tags {
    margin-top: 2rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    display: inline-flex;
    padding: 0.35rem 0.85rem;
    background-color: var(--c-primary-100);
    color: var(--c-primary-800);
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.tag-outline {
    background-color: transparent;
    border: 1px solid var(--c-primary-200);
    color: var(--c-primary-700);
}

/* ==========================================================================
   CTA SECTION
   ========================================================================== */
.cta-section {
    padding: 4rem 0;
}

.cta-card {
    padding: 4rem 2rem;
    border-radius: var(--radius-xl);
    text-align: center;
    background: var(--c-surface);
}

.cta-bg-elements {
    position: absolute;
    inset: 0;
    background-image: radial-gradient(circle at 100% 0%, var(--c-primary-50) 0%, transparent 40%),
                      radial-gradient(circle at 0% 100%, var(--c-primary-100) 0%, transparent 40%);
    opacity: 0.8;
    z-index: 0;
}

.cta-title {
    font-size: 2.25rem;
    font-weight: 800;
    color: var(--c-primary-950);
    margin-bottom: 0.5rem;
}

.cta-subtitle {
    font-size: 1.125rem;
    color: var(--c-text-muted);
}

.cta-button-wrapper {
    position: relative;
    display: inline-block;
}

.btn-primary {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1.25rem 3rem;
    background: var(--grad-primary);
    color: white;
    font-size: 1.125rem;
    font-weight: 700;
    text-decoration: none;
    border-radius: 9999px;
    box-shadow: 0 10px 25px -5px rgba(220, 38, 38, 0.4), 0 8px 10px -6px rgba(220, 38, 38, 0.4);
    overflow: hidden;
    transition: var(--transition-bounce);
    z-index: 1;
}

.btn-text {
    position: relative;
    z-index: 2;
}

.btn-icon {
    width: 1.5rem;
    height: 1.5rem;
    position: relative;
    z-index: 2;
    transition: transform 0.3s ease;
}

.btn-shine {
    position: absolute;
    top: 0;
    left: -100%;
    width: 50%;
    height: 100%;
    background: linear-gradient(to right, rgba(255,255,255,0) 0%, rgba(255,255,255,0.3) 50%, rgba(255,255,255,0) 100%);
    transform: skewX(-20deg);
    z-index: 1;
    animation: button-shine 6s infinite;
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 20px 30px -5px rgba(220, 38, 38, 0.5), 0 10px 15px -5px rgba(220, 38, 38, 0.3);
}

.btn-primary:hover .btn-icon {
    transform: translateX(4px);
}

.btn-primary:active {
    transform: translateY(1px);
    box-shadow: 0 5px 10px rgba(220, 38, 38, 0.4);
}

.btn-primary:focus-visible {
    outline: 2px solid var(--c-primary-400);
    outline-offset: 4px;
}

@keyframes button-shine {
    0%, 80% { left: -100%; }
    100% { left: 200%; }
}

/* ==========================================================================
   REVIEWS SECTION (Amazon Style, Elevated)
   ========================================================================== */
.reviews-section {
    padding: 2rem 0 6rem 0;
    max-width: 48rem;
    margin: 0 auto;
}

.section-title {
    font-size: 2rem;
    font-weight: 800;
    color: var(--c-text-main);
}

.title-underline {
    width: 60px;
    height: 4px;
    background: var(--grad-primary);
    margin: 1rem auto 0;
    border-radius: 2px;
}

.reviews-list {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.review-card {
    padding: 2rem;
    transition: var(--transition-smooth);
}

.review-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl), var(--shadow-glow);
    border-color: var(--c-primary-200);
}

.review-layout {
    display: flex;
    gap: 1.5rem;
}

.review-avatar {
    flex-shrink: 0;
}

.review-avatar img {
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--c-primary-100);
    box-shadow: var(--shadow-sm);
}

.review-body {
    flex-grow: 1;
    min-width: 0; /* Prevents text overflow */
}

.reviewer-name {
    font-size: 1rem;
    font-weight: 700;
    color: var(--c-text-main);
    margin-bottom: 0.25rem;
}

.review-rating-row {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.25rem;
}

.review-rating-row .stars .star {
    width: 1rem;
    height: 1rem;
}

.review-heading {
    font-weight: 700;
    font-size: 1rem;
    color: var(--c-text-main);
}

.review-date {
    font-size: 0.8125rem;
    color: var(--c-text-light);
    margin-bottom: 0.5rem;
}

.review-specs {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.spec-text {
    font-size: 0.75rem;
    color: var(--c-text-muted);
    border-right: 1px solid var(--c-border);
    padding-right: 0.75rem;
}

.verified-badge {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--c-primary-700);
}

.review-content {
    font-size: 0.9375rem;
    color: var(--c-text-main);
    line-height: 1.6;
}

.review-content p {
    margin: 0;
}

.review-attachment {
    margin-top: 1rem;
}

.review-attachment img {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: var(--radius-md);
    border: 1px solid var(--c-border);
    cursor: pointer;
    transition: var(--transition-fast);
}

.review-attachment img:hover {
    opacity: 0.9;
    box-shadow: var(--shadow-md);
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
    background-color: var(--c-surface);
    border-top: 1px solid var(--c-border);
    padding: 4rem 0 2rem 0;
    position: relative;
}

.site-footer::before {
    content: '';
    position: absolute;
    top: -1px;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--c-primary-300), transparent);
}

.footer-top {
    text-align: center;
    margin-bottom: 2rem;
}

.footer-logo {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--c-primary-900);
}

.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2rem;
}

.footer-link {
    font-size: 0.875rem;
    color: var(--c-text-muted);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer-link:hover, .footer-link:focus {
    color: var(--c-primary-600);
    text-decoration: underline;
}

.link-separator {
    color: var(--c-border);
}

.footer-bottom {
    text-align: center;
    font-size: 0.75rem;
    color: var(--c-text-light);
}

/* ==========================================================================
   ANIMATIONS
   ========================================================================== */
@keyframes fade-in-up {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ==========================================================================
   MEDIA QUERIES (Mobile-First approach overrides handled downward)
   ========================================================================== */

/* Very small screens (320px) */
@media (max-width: 374.98px) {
    .product-title {
        font-size: 1.75rem;
    }
    .cta-title {
        font-size: 1.5rem;
    }
    .btn-primary {
        width: 100%;
        padding: 1rem 1.5rem;
    }
    .review-layout {
        flex-direction: column;
        gap: 1rem;
    }
    .review-avatar img {
        width: 2.5rem;
        height: 2.5rem;
    }
}

/* Mobile (up to 767px) */
@media (max-width: 767.98px) {
    .product-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .product-card {
        padding: 1.5rem;
    }
    
    .header-inner {
        flex-wrap: wrap;
    }
    
    .header-empty, .header-secure {
        display: none;
    }
    
    .header-title-wrapper {
        flex: 1;
    }
    
    .thumbnails-wrapper {
        gap: 0.5rem;
    }
    
    .cta-card {
        padding: 3rem 1rem;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }
    
    .link-separator {
        display: none;
    }
    
    .spec-text {
        border-right: none;
        padding-right: 0;
        display: block;
        width: 100%;
        margin-bottom: 0.25rem;
    }
}

/* Tablet and up (768px+) */
@media (min-width: 768px) {
    .product-info {
        padding-left: 1rem;
    }
}

/* Desktop and up (1024px+) */
@media (min-width: 1024px) {
    .product-hero {
        padding: 4rem 0;
    }
    
    .product-card {
        padding: 3.5rem;
    }
    
    .product-title {
        font-size: 3rem;
    }
}

/* Large Desktop (1280px+) */
@media (min-width: 1280px) {
    .product-grid {
        gap: 5rem;
    }
}