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

:root {
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #06b6d4;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    color: var(--text-dark);
    background: linear-gradient(135deg, #868686 0%, #888788 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: var(--bg-white);
    border-radius: 24px;
    box-shadow: var(--shadow-xl);
    overflow: hidden;
}

/* Navigation */
.product-nav {
    background: var(--bg-white);
    padding: 20px;
    border-bottom: 2px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.nav-wrapper {
    display: flex;
    gap: 12px;
    max-width: 600px;
    margin: 0 auto;
}

.nav-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 20px;
    background: var(--bg-light);
    border: 2px solid transparent;
    border-radius: 12px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    color: var(--text-light);
    transition: all 0.3s ease;
}

.nav-btn:hover {
    background: #e0e7ff;
    color: var(--primary-color);
}

.nav-btn.active {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--bg-white);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.nav-btn .icon {
    font-size: 20px;
}

.nav-btn .text {
    display: none;
}

@media (min-width: 640px) {
    .nav-btn .text {
        display: inline;
    }
}

/* Product Sections */
.product-section {
    display: none;
    animation: fadeIn 0.5s ease;
}

.product-section.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Hero Section */
.product-hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--bg-white);
    padding: 60px 30px;
    text-align: center;
}

#photo-recover .product-hero {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.product-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.2;
}

.product-subtitle {
    font-size: 1.25rem;
    line-height: 1.6;
    opacity: 0.95;
}

/* Features Section */
.features-section,
.use-cases-section,
.screenshots-section,
.cta-section {
    padding: 60px 30px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-dark);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
    max-width: 900px;
    margin: 0 auto;
}

.feature-card {
    background: var(--bg-light);
    padding: 30px;
    border-radius: 16px;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 12px;
    color: var(--text-dark);
}

.feature-card p {
    color: var(--text-light);
    line-height: 1.6;
}

/* Use Cases */
.use-cases {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.use-case {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px;
    background: var(--bg-light);
    border-radius: 12px;
    font-size: 1.125rem;
}

.check-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 50%;
    font-weight: bold;
    flex-shrink: 0;
}

/* Screenshots Carousel */
.screenshots-section {
    background: var(--bg-light);
}

.screenshots-carousel {
    max-width: 900px;
    margin: 0 auto;
}

.carousel-container {
    position: relative;
    display: flex;
    align-items: center;
    gap: 20px;
}

.carousel-track-container {
    flex: 1;
    overflow: hidden;
    border-radius: 16px;
    box-shadow: var(--shadow-xl);
}

.carousel-track {
    display: flex;
    transition: transform 0.5s ease;
}

.carousel-slide {
    min-width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: #000;
}

.carousel-slide img {
    width: 100%;
    height: auto;
    display: block;
    max-height: 600px;
    object-fit: contain;
}

.carousel-btn {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--bg-white);
    border: 2px solid var(--border-color);
    color: var(--text-dark);
    font-size: 2rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.carousel-btn:hover {
    background: var(--primary-color);
    color: var(--bg-white);
    border-color: var(--primary-color);
    transform: scale(1.1);
}

.carousel-indicators {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 24px;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--border-color);
    cursor: pointer;
    transition: all 0.3s ease;
}

.indicator:hover {
    background: var(--text-light);
}

.indicator.active {
    background: var(--primary-color);
    width: 32px;
    border-radius: 6px;
}

/* CTA Section */
.cta-section {
    background: var(--bg-white);
    color: var(--text-dark);
    text-align: center;
}

.cta-text {
    font-size: 1.5rem;
    line-height: 1.6;
    max-width: 800px;
    margin: 0 auto 30px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 16px 32px;
    background: #000;
    color: #fff;
    border-radius: 12px;
    text-decoration: none;
    font-size: 1.125rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-md);
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: #333;
}

.download-btn img {
    width: 24px;
    height: 24px;
}

.download-btn .btn-text {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.download-btn .btn-text small {
    font-size: 0.75rem;
    font-weight: 400;
    opacity: 0.8;
}

.download-btn .btn-text span {
    font-size: 1.25rem;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: scale(0);
    transition: all 0.3s ease;
    z-index: 1000;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: scale(1);
}

.back-to-top:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-xl);
}

.back-to-top:active {
    transform: scale(0.95);
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    .container {
        border-radius: 16px;
    }

    .product-title {
        font-size: 2rem;
    }

    .product-subtitle {
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .product-hero,
    .features-section,
    .use-cases-section,
    .screenshots-section,
    .cta-section {
        padding: 40px 20px;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .download-btn {
        padding: 14px 24px;
        font-size: 1rem;
    }

    .download-btn .btn-text span {
        font-size: 1.125rem;
    }

    .carousel-btn {
        width: 40px;
        height: 40px;
        font-size: 1.5rem;
    }

    .cta-text {
        font-size: 1.125rem;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 45px;
        height: 45px;
    }
}

@media (max-width: 480px) {
    .carousel-container {
        gap: 10px;
    }

    .carousel-btn {
        width: 35px;
        height: 35px;
        font-size: 1.25rem;
    }
}