/* ==========================================================================
   VISUAL ADVANTAGE LUNOVUS EYELID FOAM - CUSTOM DESIGN SYSTEM
   Theme: Elegant Yellow/Amber Palette
   Type: CSS-Only Landing Page (No JS)
   Lines target: 800+
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. CSS VARIABLES (Theme Definition)
   -------------------------------------------------------------------------- */
:root {
    /* Color Palette - strictly Yellow/Amber based as per prompt */
    --color-primary: #eab308;       /* Tailwind yellow-500 */
    --color-primary-light: #fef08a; /* Tailwind yellow-200 */
    --color-primary-dark: #ca8a04;  /* Tailwind yellow-600 */
    --color-primary-darker: #a16207;/* Tailwind yellow-700 */
    --color-accent: #f59e0b;        /* Tailwind amber-500 */
    
    --color-bg-page: #fefce8;       /* Tailwind yellow-50 */
    --color-bg-card: #ffffff;
    --color-bg-subtle: #fef9c3;     /* Tailwind yellow-100 */
    
    --color-text-main: #1f2937;     /* Tailwind gray-800 */
    --color-text-heading: #111827;  /* Tailwind gray-900 */
    --color-text-muted: #6b7280;    /* Tailwind gray-500 */
    
    --color-border-light: #fef08a;  /* Yellow-200 */
    --color-border-subtle: #fef9c3; /* Yellow-100 */
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-primary) 100%);
    --gradient-glow: linear-gradient(180deg, rgba(253,224,71,0.4) 0%, rgba(253,224,71,0) 100%);
    --gradient-border: linear-gradient(to right, #fef08a, #eab308, #fef08a);
    --gradient-btn: linear-gradient(135deg, #fcd34d 0%, #fbbf24 50%, #f59e0b 100%);
    
    /* Shadows - Layered and deep, tinted with yellow */
    --shadow-soft: 0 4px 20px -2px rgba(234, 179, 8, 0.08);
    --shadow-medium: 0 10px 30px -5px rgba(234, 179, 8, 0.12), 0 4px 10px -2px rgba(234, 179, 8, 0.08);
    --shadow-heavy: 0 20px 40px -10px rgba(202, 138, 4, 0.15), 0 10px 20px -5px rgba(202, 138, 4, 0.1);
    --shadow-btn: 0 10px 25px -5px rgba(245, 158, 11, 0.4), 0 8px 10px -6px rgba(245, 158, 11, 0.3);
    --shadow-btn-hover: 0 15px 35px -5px rgba(245, 158, 11, 0.5), 0 10px 15px -5px rgba(245, 158, 11, 0.4);
    --shadow-inner-gallery: inset 0 2px 15px rgba(0,0,0,0.03);
    
    /* Radii */
    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1.25rem;
    --radius-xl: 2rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
    
    /* Layout */
    --header-height: 5rem;
}

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

body.theme-yellow-page {
    background-color: var(--color-bg-page);
    color: var(--color-text-main);
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    overflow-x: hidden;
    position: relative;
}

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

::-webkit-scrollbar {
    width: 10px;
}
::-webkit-scrollbar-track {
    background: var(--color-bg-page);
}
::-webkit-scrollbar-thumb {
    background: var(--color-primary-light);
    border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--color-primary);
}

/* --------------------------------------------------------------------------
   3. BACKGROUND AMBIENT BLOBS (Decorations)
   -------------------------------------------------------------------------- */
.ambient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    overflow: hidden;
    pointer-events: none;
}

.ambient-blob {
    position: absolute;
    filter: blur(80px);
    border-radius: 50%;
    opacity: 0.4;
    animation: blob-float 20s infinite alternate cubic-bezier(0.45, 0.05, 0.55, 0.95);
}

.blob-1 {
    width: 600px;
    height: 600px;
    background: var(--color-primary-light);
    top: -200px;
    left: -200px;
    animation-delay: 0s;
}

.blob-2 {
    width: 500px;
    height: 500px;
    background: #fde047;
    bottom: 10%;
    right: -150px;
    animation-delay: -5s;
    opacity: 0.3;
}

.blob-3 {
    width: 400px;
    height: 400px;
    background: var(--color-bg-subtle);
    top: 40%;
    left: 20%;
    animation-delay: -10s;
}

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

/* --------------------------------------------------------------------------
   4. HEADER STYLES
   -------------------------------------------------------------------------- */
.site-header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: 0 1px 3px rgba(0,0,0,0.02), 0 4px 20px rgba(234, 179, 8, 0.05);
}

.header-decoration-line {
    height: 3px;
    width: 100%;
    background: var(--gradient-border);
    position: absolute;
    bottom: 0;
    left: 0;
}

.brand-icon-wrapper {
    background: var(--color-primary-light);
    color: var(--color-primary-darker);
    padding: 0.5rem;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: inset 0 2px 4px rgba(255,255,255,0.5), 0 2px 5px rgba(234,179,8,0.2);
}

.brand-name {
    background: linear-gradient(to right, var(--color-text-heading), var(--color-primary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.trust-badge-text {
    background-color: var(--color-bg-page);
    border: 1px solid var(--color-primary-light);
    color: var(--color-primary-dark);
}

/* --------------------------------------------------------------------------
   5. PRODUCT HERO SECTION
   -------------------------------------------------------------------------- */
.product-card-container {
    position: relative;
    z-index: 10;
    margin: 0 auto;
}

.product-card-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(253,224,71,0.15) 0%, rgba(255,255,255,0) 70%);
    z-index: -1;
    pointer-events: none;
}

.product-card-inner {
    background-color: var(--color-bg-card);
    border-radius: var(--radius-xl);
    padding: 2rem;
    box-shadow: var(--shadow-heavy);
    border: 1px solid rgba(255, 255, 255, 0.8);
    position: relative;
    overflow: hidden;
}

/* Subtle corner decoration on product card */
.product-card-inner::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 150px;
    height: 150px;
    background: radial-gradient(circle at top right, var(--color-primary-light) 0%, transparent 70%);
    opacity: 0.5;
    pointer-events: none;
}

@media (min-width: 1024px) {
    .product-card-inner {
        padding: 3.5rem;
    }
}

/* --------------------------------------------------------------------------
   6. CSS-ONLY GALLERY (The Magic)
   -------------------------------------------------------------------------- */
.product-gallery-column {
    position: relative;
}

.css-gallery-wrapper {
    display: flex;
    flex-direction: column;
    width: 100%;
}

.gallery-main-view {
    background-color: var(--color-bg-page);
    border: 1px solid var(--color-border-subtle);
    aspect-ratio: 4/4;
    position: relative;
    box-shadow: var(--shadow-inner-gallery);
}

@media (min-width: 768px) {
    .gallery-main-view { aspect-ratio: 4/3; }
}
@media (min-width: 1024px) {
    .gallery-main-view { aspect-ratio: 1/1; }
}

.gallery-main-bg-shape {
    width: 70%;
    height: 70%;
    background: radial-gradient(circle, var(--color-primary-light) 0%, transparent 80%);
}

.gallery-slide {
    opacity: 0;
    visibility: hidden;
    transform: scale(0.95);
    transition: all var(--transition-slow);
}

.gallery-img {
    max-height: 100%;
    max-width: 100%;
    transition: transform var(--transition-bounce);
}

/* State logic for main images */
#gallery-img-1:checked ~ .gallery-main-view .slide-1,
#gallery-img-2:checked ~ .gallery-main-view .slide-2,
#gallery-img-3:checked ~ .gallery-main-view .slide-3,
#gallery-img-4:checked ~ .gallery-main-view .slide-4 {
    opacity: 1;
    visibility: visible;
    transform: scale(1);
}

/* Hover effect on main image */
.gallery-slide:hover .gallery-img {
    transform: scale(1.05);
}

/* Thumbnails General Styles */
.gallery-thumbnails {
    position: relative;
}

.thumb-label {
    border: 2px solid transparent;
    background-color: var(--color-bg-page);
}

.thumb-overlay {
    background-color: rgba(255,255,255,0.4);
    z-index: 10;
}

.thumb-label:hover {
    border-color: var(--color-primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-soft);
}

.thumb-label:hover .thumb-overlay {
    opacity: 0;
}

.thumb-indicator {
    background-color: var(--color-primary);
    transform: scaleX(0);
    transform-origin: bottom center;
}

/* State logic for thumbnails active borders and indicators */
#gallery-img-1:checked ~ .gallery-thumbnails label[for="gallery-img-1"],
#gallery-img-2:checked ~ .gallery-thumbnails label[for="gallery-img-2"],
#gallery-img-3:checked ~ .gallery-thumbnails label[for="gallery-img-3"],
#gallery-img-4:checked ~ .gallery-thumbnails label[for="gallery-img-4"] {
    border-color: var(--color-primary);
    box-shadow: 0 4px 12px rgba(234, 179, 8, 0.2);
}

#gallery-img-1:checked ~ .gallery-thumbnails label[for="gallery-img-1"] .thumb-overlay,
#gallery-img-2:checked ~ .gallery-thumbnails label[for="gallery-img-2"] .thumb-overlay,
#gallery-img-3:checked ~ .gallery-thumbnails label[for="gallery-img-3"] .thumb-overlay,
#gallery-img-4:checked ~ .gallery-thumbnails label[for="gallery-img-4"] .thumb-overlay {
    opacity: 0;
}

#gallery-img-1:checked ~ .gallery-thumbnails label[for="gallery-img-1"] .thumb-indicator,
#gallery-img-2:checked ~ .gallery-thumbnails label[for="gallery-img-2"] .thumb-indicator,
#gallery-img-3:checked ~ .gallery-thumbnails label[for="gallery-img-3"] .thumb-indicator,
#gallery-img-4:checked ~ .gallery-thumbnails label[for="gallery-img-4"] .thumb-indicator {
    transform: scaleX(1);
}

/* --------------------------------------------------------------------------
   7. PRODUCT DETAILS SECTION
   -------------------------------------------------------------------------- */
.product-category-badge span {
    background-color: var(--color-primary-light);
    color: var(--color-primary-darker);
    border: 1px solid rgba(234, 179, 8, 0.3);
}

.product-title {
    position: relative;
    display: inline-block;
}

.title-underline {
    animation: slide-right 1s ease-out forwards;
    transform-origin: left;
}

@keyframes slide-right {
    0% { stroke-dasharray: 0 100; opacity: 0; }
    100% { stroke-dasharray: 100 100; opacity: 1; }
}

/* Feature Items Customization */
.feature-item {
    background: transparent;
    border: 1px solid transparent;
}

.feature-item:hover {
    background: linear-gradient(90deg, var(--color-bg-page) 0%, transparent 100%);
    border-left: 3px solid var(--color-primary);
    transform: translateX(4px);
    box-shadow: var(--shadow-soft);
}

.feature-check {
    background: var(--color-primary-light);
    color: var(--color-primary-darker);
    transition: all var(--transition-base);
}

.feature-item:hover .feature-check {
    background: var(--color-primary);
    color: #fff;
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 4px 10px rgba(234, 179, 8, 0.4);
}

/* --------------------------------------------------------------------------
   8. CTA SECTION (Call to Action)
   -------------------------------------------------------------------------- */
.cta-section {
    background-color: var(--color-bg-subtle);
    border-top: 1px dashed var(--color-border-light);
    border-bottom: 1px dashed var(--color-border-light);
}

.cta-bg-shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    z-index: 0;
    opacity: 0.5;
}

.cta-bg-shape.shape-1 {
    width: 400px;
    height: 400px;
    background: var(--color-primary);
    top: -100px;
    left: -100px;
}

.cta-bg-shape.shape-2 {
    width: 300px;
    height: 300px;
    background: var(--color-primary-light);
    bottom: -50px;
    right: -50px;
}

/* Massive CTA Button */
.cta-button {
    box-shadow: var(--shadow-btn);
    transform: translateY(0);
}

.cta-btn-bg {
    background: var(--gradient-btn);
    transition: opacity var(--transition-base);
}

.cta-button:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-btn-hover);
}

.cta-button:active {
    transform: translateY(1px);
    box-shadow: var(--shadow-soft);
}

/* Shine effect animation */
.cta-btn-shine {
    background: linear-gradient(to right, rgba(255,255,255,0) 0%, rgba(255,255,255,0.4) 50%, rgba(255,255,255,0) 100%);
    width: 50%;
}

@keyframes shine {
    100% {
        transform: skewX(-12deg) translateX(250%);
    }
}

/* Pulse Ring */
.cta-pulse-ring {
    border: 2px solid var(--color-primary);
    animation: pulse-ring 2.5s cubic-bezier(0.215, 0.61, 0.355, 1) infinite;
}

@keyframes pulse-ring {
    0% {
        transform: scale(0.95);
        opacity: 0.8;
    }
    70% {
        transform: scale(1.15);
        opacity: 0;
    }
    100% {
        transform: scale(0.95);
        opacity: 0;
    }
}

/* --------------------------------------------------------------------------
   9. REVIEWS SECTION (Amazon-Style Elevated)
   -------------------------------------------------------------------------- */
.reviews-section {
    position: relative;
    z-index: 10;
}

.review-card {
    /* Amazon format but much nicer */
    border-left: 4px solid transparent;
}

.review-card:hover {
    border-left-color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.avatar-wrapper img {
    transition: transform var(--transition-base);
}

.review-card:hover .avatar-wrapper img {
    transform: scale(1.05) rotate(-2deg);
}

.avatar-backdrop {
    opacity: 0.2;
    transition: opacity var(--transition-base);
}

.review-card:hover .avatar-backdrop {
    opacity: 0.4;
}

.review-attributes span {
    position: relative;
    padding-left: 1.5rem;
}

/* Custom checkmark for "Verified Purchase" using pseudo-element */
.review-attributes span::before {
    content: '';
    position: absolute;
    left: 0.5rem;
    top: 50%;
    transform: translateY(-50%);
    width: 0.75rem;
    height: 0.75rem;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20' fill='%23a16207'%3E%3Cpath fill-rule='evenodd' d='M16.707 5.293a1 1 0 010 1.414l-8 8a1 1 0 01-1.414 0l-4-4a1 1 0 011.414-1.414L8 12.586l7.293-7.293a1 1 0 011.414 0z' clip-rule='evenodd'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: center;
}

/* --------------------------------------------------------------------------
   10. FOOTER STYLES
   -------------------------------------------------------------------------- */
.site-footer {
    border-top: 4px solid var(--color-primary);
}

.footer-wave-top svg {
    filter: drop-shadow(0 5px 5px rgba(0,0,0,0.02));
}

.footer-link-group ul li {
    position: relative;
}

.footer-link {
    position: relative;
}

.footer-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--color-primary);
    transition: width var(--transition-fast);
}

.footer-link:hover::after {
    width: 100%;
}

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

.footer-link:hover .link-bullet {
    transform: scale(1.5);
    background-color: var(--color-primary-dark);
}

/* --------------------------------------------------------------------------
   11. MEDIA QUERIES (Responsive Fine-tuning)
   -------------------------------------------------------------------------- */
/* Extra Small Devices */
@media (max-width: 480px) {
    .product-title {
        font-size: 2rem;
    }
    
    .cta-button {
        padding-left: 1.5rem;
        padding-right: 1.5rem;
        font-size: 1.125rem;
    }
    
    .review-card {
        padding: 1.25rem;
    }
    
    .feature-item {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .feature-icon-wrapper {
        margin-top: 0;
    }
}

/* Small to Medium Devices */
@media (min-width: 481px) and (max-width: 768px) {
    .product-card-inner {
        padding: 1.5rem;
    }
    
    .gallery-thumbnails {
        gap: 0.5rem;
    }
}

/* Medium to Large (Tablet) */
@media (min-width: 769px) and (max-width: 1024px) {
    .product-hero-section {
        padding-top: 3rem;
        padding-bottom: 3rem;
    }
}

/* Large and above */
@media (min-width: 1025px) {
    .product-card-container {
        max-width: 1100px;
    }
    
    .review-card {
        margin-left: auto;
        margin-right: auto;
        max-width: 900px;
    }
}

/* Fix for gallery layout on Desktop */
@media (min-width: 1024px) {
    .css-gallery-wrapper {
        position: sticky;
        top: 6rem;
    }
}

/* ==========================================================================
   END OF CUSTOM CSS
   ========================================================================== */