/* Modern Styles for 10 Dogs Website - 2025 Edition */
:root {
    --primary-color: #3A7BD5;
    --primary-gradient: linear-gradient(135deg, #3A7BD5, #00d2ff);
    --secondary-color: #FF9500;
    --accent-color: #FF3B30;
    --success-color: #34C759;
    --text-color: #333333;
    --text-light: #8A8A8E;
    --light-bg: #F8F9FA;
    --white: #ffffff;
    --border-color: #E5E5EA;
    --card-shadow: 0 10px 30px rgba(0,0,0,0.08);
    --transition-fast: 0.3s ease;
    --transition-slow: 0.5s ease;
    --border-radius-sm: 8px;
    --border-radius-md: 12px;
    --border-radius-lg: 24px;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-md: 1rem;
    --font-size-lg: 1.25rem;
    --font-size-xl: 1.5rem;
    --font-size-xxl: 2rem;
    --font-size-xxxl: 3rem;
}

/* Base Styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Nunito Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--light-bg);
    margin: 0;
    padding: 0;
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Grid System */
.grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: var(--spacing-lg);
}

/* Header Styles */
header {
    background: var(--primary-gradient);
    color: var(--white);
    position: relative;
    overflow: hidden;
    padding: var(--spacing-xxl) 0;
}

.header-content {
    position: relative;
    z-index: 2;
    padding: var(--spacing-xxl) var(--spacing-lg);
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.header-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('images/header-bg.jpg');
    background-size: cover;
    background-position: center;
    opacity: 0.15;
    z-index: 1;
}

.header-bg::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--primary-gradient);
    opacity: 0.7;
}

.site-title {
    font-size: var(--font-size-xxxl);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    color: var(--white);
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    animation: fadeInDown 1s ease-out;
    line-height: 1.2;
    margin-top: var(--spacing-xl);
}

.site-subtitle {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-xl);
    color: rgba(255,255,255,0.9);
    animation: fadeInUp 1s ease-out;
    font-weight: 600;
}

/* Navigation */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: all var(--transition-fast);
    padding: var(--spacing-sm) 0;
    transform: translateY(0);
}

.main-nav.hidden {
    transform: translateY(-100%);
}

.main-nav.scrolled {
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
    padding: var(--spacing-sm) 0;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-weight: 800;
    font-size: var(--font-size-lg);
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    transition: all var(--transition-fast);
}

.logo:hover {
    transform: scale(1.05);
}

.logo::before {
    content: '🐾';
    margin-right: var(--spacing-xs);
    font-size: 1.2em;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: var(--text-color);
    font-weight: 600;
    position: relative;
    padding: var(--spacing-xs) var(--spacing-sm);
    transition: all var(--transition-fast);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-gradient);
    transition: width var(--transition-fast);
    border-radius: 2px;
}

.nav-links a:hover {
    color: var(--primary-color);
}

.nav-links a:hover::after {
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    font-size: var(--font-size-xl);
    color: var(--text-color);
    transition: all var(--transition-fast);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.mobile-menu-toggle:hover {
    background-color: rgba(0,0,0,0.05);
    color: var(--primary-color);
}

.mobile-menu-toggle.active {
    color: var(--primary-color);
}

.mobile-menu {
    position: fixed;
    top: 60px;
    left: 0;
    width: 100%;
    background-color: var(--white);
    padding: 0;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: 999;
    max-height: 0;
    overflow: hidden;
}

.mobile-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    max-height: 300px;
    padding: var(--spacing-md);
}

.mobile-menu ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.mobile-menu li {
    margin-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.mobile-menu li:last-child {
    margin-bottom: 0;
    border-bottom: none;
}

.mobile-menu a {
    display: block;
    padding: var(--spacing-sm) 0;
    font-size: var(--font-size-md);
    color: var(--text-color);
    font-weight: 600;
    transition: all var(--transition-fast);
}

.mobile-menu a:hover {
    color: var(--primary-color);
    padding-left: var(--spacing-sm);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: var(--text-color);
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: var(--font-size-xxxl);
}

h2 {
    font-size: var(--font-size-xxl);
    text-align: center;
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-xl);
    position: relative;
    padding-bottom: var(--spacing-md);
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--primary-gradient);
    border-radius: 2px;
}

h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-md);
}

h4 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
}

h5 {
    font-size: var(--font-size-md);
    margin-bottom: var(--spacing-sm);
}

p {
    font-size: var(--font-size-md);
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

/* Product Sections */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(550px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xxl);
}

.product-section {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: all var(--transition-fast);
    display: flex;
    flex-direction: column;
    height: 100%;
    position: relative;
}

.product-section:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.product-header {
    padding: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.product-number {
    font-size: var(--font-size-xxl);
    font-weight: 800;
    color: var(--secondary-color);
    line-height: 1;
}

.product-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    margin: 0;
    flex: 1;
}

.product-image-container {
    position: relative;
    overflow: hidden;
    aspect-ratio: 16 / 9;
}

.product-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

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

.product-badge {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background-color: var(--accent-color);
    color: var(--white);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 50px;
    font-weight: 700;
    font-size: var(--font-size-sm);
    z-index: 2;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.product-content {
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.problem-solution {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.problem, .solution {
    padding: var(--spacing-md);
    border-radius: var(--border-radius-sm);
    position: relative;
}

.problem {
    background-color: rgba(255, 59, 48, 0.1);
    border-left: 4px solid var(--accent-color);
}

.solution {
    background-color: rgba(52, 199, 89, 0.1);
    border-left: 4px solid var(--success-color);
}

.problem h5, .solution h5 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
}

.problem h5::before, .solution h5::before {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    background-size: contain;
    background-repeat: no-repeat;
}

.problem h5::before {
    background-image: url('images/problem-icon.svg');
}

.solution h5::before {
    background-image: url('images/solution-icon.svg');
}

.social-proof {
    background-color: rgba(255, 149, 0, 0.1);
    padding: var(--spacing-md);
    border-radius: var(--border-radius-sm);
    margin-top: auto;
    margin-bottom: var(--spacing-lg);
    border-left: 4px solid var(--secondary-color);
}

.social-proof p {
    margin: 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.social-proof p::before {
    content: '';
    display: inline-block;
    width: 50px;
    height: 50px;
    background-image: url('images/star-icon.svg');
    background-size: contain;
    background-repeat: no-repeat;
    background-position-y: center;
}

/* CTA Button */
.button-container {
    text-align: center;
    margin-top: auto;
}

.cta-button {
    display: inline-block;
    background: var(--secondary-color);
    color: var(--white);
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--border-radius-sm);
    font-weight: 700;
    font-size: var(--font-size-md);
    text-align: center;
    transition: all var(--transition-fast);
    box-shadow: 0 4px 12px rgba(255, 149, 0, 0.3);
    position: relative;
    overflow: hidden;
    width: 100%;
}

.cta-button::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: 0.5s;
}

.cta-button:hover {
    background-color: #FF8000;
    transform: translateY(-3px);
    box-shadow: 0 6px 15px rgba(255, 149, 0, 0.4);
}

.cta-button:hover::after {
    left: 100%;
}

.header-cta {
    background: var(--white);
    color: var(--primary-color);
    font-weight: 700;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--border-radius-sm);
    display: inline-block;
    margin-top: var(--spacing-lg);
    box-shadow: 0 10px 20px rgba(0,0,0,0.15);
    transition: all var(--transition-fast);
}

.header-cta:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.2);
}

/* Intro and Conclusion Sections */
.intro, .conclusion {
    background-color: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-md);
    margin: var(--spacing-xl) 0;
    box-shadow: var(--card-shadow);
    position: relative;
    border-left: 5px solid var(--primary-color);
}

.intro::before, .conclusion::before {
    content: '';
    position: absolute;
    top: var(--spacing-lg);
    left: -15px;
    width: 25px;
    height: 25px;
    background-color: var(--primary-color);
    border-radius: 50%;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

/* Footer */
footer {
    background: var(--primary-gradient);
    color: var(--white);
    padding: var(--spacing-xxl) 0;
    margin-top: var(--spacing-xxl);
    position: relative;
    overflow: hidden;
}

.footer-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('images/footer-pattern.svg');
    background-size: cover;
    opacity: 0.1;
    z-index: 1;
}

.footer-content {
    position: relative;
    z-index: 2;
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    padding: 0 var(--spacing-lg);
}

.footer-column h3 {
    color: var(--white);
    margin-bottom: var(--spacing-lg);
    font-size: var(--font-size-lg);
    position: relative;
    padding-bottom: var(--spacing-sm);
}

.footer-column h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 3px;
    background-color: var(--secondary-color);
}

.footer-links {
    list-style: none;
    margin: 0;
    padding: 0;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: rgba(255,255,255,0.8);
    transition: all var(--transition-fast);
}

.footer-links a:hover {
    color: var(--white);
    padding-left: var(--spacing-xs);
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: rgba(255,255,255,0.1);
    border-radius: 50%;
    color: var(--white);
    transition: all var(--transition-fast);
}

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

.copyright {
    text-align: center;
    padding-top: var(--spacing-xl);
    margin-top: var(--spacing-xl);
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.7);
    font-size: var(--font-size-sm);
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.highlight {
    color: var(--accent-color);
    font-weight: 700;
}

.mb-0 {
    margin-bottom: 0;
}

.mt-0 {
    margin-top: 0;
}

.hidden {
    display: none;
}

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

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

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

.animate-pulse {
    animation: pulse 2s infinite;
}

.animate-fade-in {
    animation: fadeIn 1s ease-out;
}

.animate-fade-in-up {
    animation: fadeInUp 1s ease-out;
}

.animate-fade-in-down {
    animation: fadeInDown 1s ease-out;
}

/* Stats Section */
.stats-section {
    padding: var(--spacing-xl) 0;
    margin: var(--spacing-xxl) 0;
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    box-shadow: var(--card-shadow);
}

.stats-section .grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.stat-card {
    text-align: center;
    padding: var(--spacing-lg);
    transition: all var(--transition-fast);
}

.stat-card:hover {
    transform: translateY(-5px);
}

.stat-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
}

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--secondary-color);
    margin-bottom: var(--spacing-xs);
    line-height: 1;
}

.stat-label {
    font-size: var(--font-size-md);
    color: var(--text-light);
    font-weight: 600;
}

/* Testimonials Section */
.testimonials-section {
    margin: var(--spacing-xxl) 0;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.testimonial {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: all var(--transition-fast);
}

.testimonial:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.1);
}

.testimonial-content {
    padding: var(--spacing-lg);
    position: relative;
}

.testimonial-content i {
    font-size: 2rem;
    color: var(--primary-color);
    opacity: 0.2;
    position: absolute;
    top: var(--spacing-md);
    left: var(--spacing-md);
}

.testimonial-content p {
    position: relative;
    z-index: 1;
    font-style: italic;
    margin-bottom: 0;
    padding-left: var(--spacing-lg);
}

.testimonial-author {
    display: flex;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: rgba(58, 123, 213, 0.05);
    border-top: 1px solid var(--border-color);
}

.author-image {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    margin-right: var(--spacing-md);
    object-fit: cover;
}

.author-info h5 {
    margin: 0;
    font-weight: 700;
    font-size: var(--font-size-md);
}

.author-info p {
    margin: 0;
    font-size: var(--font-size-sm);
    color: var(--text-light);
}

/* Contact Section */
.contact-section {
    margin: var(--spacing-xxl) 0;
    text-align: center;
}

.subscribe-form {
    max-width: 600px;
    margin: var(--spacing-xl) auto;
}

.form-group {
    display: flex;
    margin-bottom: var(--spacing-md);
}

.form-group input {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm) 0 0 var(--border-radius-sm);
    font-size: var(--font-size-md);
    outline: none;
    transition: all var(--transition-fast);
}

.form-group input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(58, 123, 213, 0.2);
}

.subscribe-button {
    background: var(--primary-gradient);
    color: var(--white);
    border: none;
    padding: 0 var(--spacing-xl);
    border-radius: 0 var(--border-radius-sm) var(--border-radius-sm) 0;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.subscribe-button:hover {
    background: linear-gradient(135deg, #2A6AC5, #00b2df);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.form-disclaimer {
    font-size: var(--font-size-sm);
    color: var(--text-light);
}

/* Featured Product */
.featured-product {
    grid-column: 1 / -1;
    background: linear-gradient(135deg, #ffffff, #f0f7ff);
    border: 2px solid rgba(58, 123, 213, 0.2);
}

.featured-product .product-badge {
    background-color: var(--primary-color);
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: -28px;
    left: calc(50% - 38px);
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    color: rgba(255,255,255,0.8);
    font-size: var(--font-size-sm);
    animation: bounce 2s infinite;
    transition: all var(--transition-fast);
}

.scroll-indicator span {
    margin-bottom: var(--spacing-xs);
}

.scroll-indicator i {
    font-size: var(--font-size-lg);
}

.scroll-indicator.hidden {
    opacity: 0;
    visibility: hidden;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(-10px);
    }
    60% {
        transform: translateY(-5px);
    }
}

/* Ripple Effect for Buttons */
.cta-button {
    position: relative;
    overflow: hidden;
}

.ripple {
    position: absolute;
    border-radius: 50%;
    background-color: rgba(255,255,255,0.4);
    transform: scale(0);
    animation: ripple 0.6s linear;
    pointer-events: none;
}

@keyframes ripple {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    background-color: var(--primary-color);
    color: var(--white);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: 1000;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--secondary-color);
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.2);
}

/* Responsive Design */
@media (max-width: 1200px) {
    :root {
        --font-size-xxxl: 2.5rem;
        --font-size-xxl: 1.8rem;
    }
    
    /* .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(550px, 1fr));
    } */
}

@media (max-width: 992px) {
    :root {
        --font-size-xxxl: 2.2rem;
        --font-size-xxl: 1.6rem;
        --font-size-xl: 1.3rem;
    }
    
    .header-content {
        padding: var(--spacing-xl) var(--spacing-md);
    }
    
    .products-grid {
        /* grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); */
        gap: var(--spacing-lg);
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-xxxl: 2rem;
        --font-size-xxl: 1.5rem;
        --spacing-xxl: 32px;
    }
    
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .nav-links {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .mobile-menu {
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        background-color: var(--white);
        padding: var(--spacing-md);
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        transform: translateY(-100%);
        opacity: 0;
        transition: all var(--transition-fast);
        z-index: 999;
    }
    
    .mobile-menu.active {
        transform: translateY(0);
        opacity: 1;
    }
    
    .mobile-menu ul {
        list-style: none;
    }
    
    .mobile-menu li {
        margin-bottom: var(--spacing-md);
    }
    
    .mobile-menu a {
        display: block;
        padding: var(--spacing-sm) 0;
        font-size: var(--font-size-lg);
    }
    
    .products-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .product-header {
        flex-direction: row;
        align-items: center;
    }
    
    .product-number {
        margin-bottom: 0;
    }
    
    .problem-solution {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-column h3::after {
        left: 50%;
        transform: translateX(-50%);
    }
    
    .social-links {
        justify-content: center;
    }
}

@media (max-width: 576px) {
    :root {
        --font-size-xxxl: 1.8rem;
        --font-size-xxl: 1.4rem;
        --font-size-xl: 1.2rem;
        --spacing-xl: 24px;
    }
    
    .site-title {
        font-size: var(--font-size-xxl);
    }
    
    .site-subtitle {
        font-size: var(--font-size-md);
    }
    
    .header-content {
        padding: var(--spacing-lg) var(--spacing-sm);
    }
    
    .intro, .conclusion {
        padding: var(--spacing-lg);
    }
    
    .product-section {
        margin-bottom: var(--spacing-lg);
    }
    
    .product-header {
        padding: var(--spacing-md);
    }
    
    .product-content {
        padding: var(--spacing-md);
    }
    
    .back-to-top {
        width: 40px;
        height: 40px;
        bottom: var(--spacing-md);
        right: var(--spacing-md);
    }
}