/* ===================================
   CavaLunagroup - Minimalist Design
   =================================== */

/* CSS Variables */
:root {
    --color-primary: #1a1a1a;
    --color-secondary: #666;
    --color-accent: #000;
    --color-bg: #ffffff;
    --color-bg-light: #fafafa;
    --color-border: #e5e5e5;
    --color-text: #333;
    --color-text-light: #666;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: var(--font-primary);
    font-weight: 400;
    line-height: 1.7;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header & Navigation */
.header {
    position: sticky;
    top: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: var(--transition);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) 0;
}

.logo a {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--color-accent);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-menu a {
    font-size: 0.9375rem;
    font-weight: 400;
    color: var(--color-text-light);
    position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--color-accent);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-accent);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-accent);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    padding: var(--spacing-xl) 0;
    text-align: center;
    background: var(--color-bg);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 600;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: var(--spacing-sm);
    color: var(--color-accent);
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    font-weight: 300;
    color: var(--color-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Search Section */
.search-section {
    padding: var(--spacing-md) 0;
    background: var(--color-bg-light);
}

.search-box {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    background: white;
    border: 1px solid var(--color-border);
    border-radius: 0;
    overflow: hidden;
    transition: var(--transition);
}

.search-box:focus-within {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.05);
}

.search-box input {
    flex: 1;
    padding: 1rem 1.5rem;
    border: none;
    font-size: 0.9375rem;
    outline: none;
}

.search-box button {
    padding: 0 1.5rem;
    background: transparent;
    transition: var(--transition);
}

.search-box button:hover {
    background: var(--color-bg-light);
}

/* Search Results Info */
.search-results-info {
    margin-bottom: var(--spacing-md);
    padding: 1rem 0;
}

.search-results-info p {
    font-size: 1rem;
    color: var(--color-text-light);
}

.search-results-info strong {
    color: var(--color-accent);
    font-weight: 600;
}

/* Categories */
.categories {
    padding: var(--spacing-lg) 0;
    background: var(--color-bg);
}

.category-filter {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    justify-content: center;
}

.category-btn {
    padding: 0.625rem 1.5rem;
    font-size: 0.875rem;
    font-weight: 400;
    color: var(--color-text-light);
    background: transparent;
    border: 1px solid var(--color-border);
    transition: var(--transition);
    white-space: nowrap;
}

.category-btn:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.category-btn.active {
    background: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
}

/* Articles Grid */
.articles {
    padding: var(--spacing-lg) 0 var(--spacing-xl);
    background: var(--color-bg);
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.article-card {
    background: white;
    transition: var(--transition);
    opacity: 0;
    animation: fadeInUp 0.3s ease forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.article-card:hover {
    transform: translateY(-4px);
}

.article-image {
    width: 100%;
    aspect-ratio: 16 / 10;
    overflow: hidden;
    background: var(--color-bg-light);
    position: relative;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease, opacity 0.3s ease;
}

/* Image Loading States */
.image-container {
    width: 100%;
    height: 100%;
    position: relative;
    overflow: hidden;
}

.image-container.loading {
    background: linear-gradient(
        90deg,
        #f0f0f0 25%,
        #e0e0e0 50%,
        #f0f0f0 75%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
}

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

.image-container.loading img {
    opacity: 0;
}

.image-container.loaded img {
    opacity: 1;
}

.image-container.error {
    background: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-container.error::after {
    content: '⚠';
    font-size: 2rem;
    color: #999;
}

/* Lazy Image */
.lazy-image {
    opacity: 0;
    transition: opacity 0.3s ease;
}

.lazy-image.loaded {
    opacity: 1;
}

.article-card:hover .article-image img {
    transform: scale(1.05);
}

.article-content {
    padding: var(--spacing-md);
}

.article-meta {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    font-size: 0.8125rem;
    color: var(--color-text-light);
}

.article-category {
    font-weight: 500;
    color: var(--color-accent);
}

.article-title {
    font-size: 1.25rem;
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
    color: var(--color-accent);
}

.article-excerpt {
    font-size: 0.9375rem;
    line-height: 1.6;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

.read-more {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-accent);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.read-more::after {
    content: '→';
    transition: transform 0.3s ease;
}

.article-card:hover .read-more::after {
    transform: translateX(4px);
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

.page-btn {
    min-width: 40px;
    height: 40px;
    padding: 0 1rem;
    font-size: 0.875rem;
    color: var(--color-text);
    background: transparent;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

.page-btn:hover:not(.active) {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.page-btn.active {
    background: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
}

/* Page Hero */
.page-hero {
    padding: var(--spacing-xl) 0 var(--spacing-lg);
    text-align: center;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.page-hero h1 {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--color-accent);
    margin-bottom: var(--spacing-sm);
}

.page-hero p {
    font-size: 1.125rem;
    color: var(--color-text-light);
}

/* About Content */
.about-content {
    padding: var(--spacing-xl) 0;
}

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

.about-text h2 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    margin-top: var(--spacing-lg);
    color: var(--color-accent);
}

.about-text h2:first-child {
    margin-top: 0;
}

.about-text p {
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
}

.about-categories {
    display: grid;
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
}

.about-category {
    padding: var(--spacing-md);
    background: var(--color-bg-light);
    border-left: 2px solid var(--color-accent);
}

.about-category h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--color-accent);
}

.about-category p {
    font-size: 0.9375rem;
    color: var(--color-text-light);
    margin: 0;
}

/* Contact Content */
.contact-content {
    padding: var(--spacing-xl) 0;
}

.contact-wrapper {
    max-width: 1000px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

.contact-info h2 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--color-accent);
}

.contact-info > p {
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-lg);
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.contact-method h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--color-accent);
}

.contact-method p {
    font-size: 0.9375rem;
    color: var(--color-text-light);
}

.contact-method a {
    color: var(--color-accent);
    text-decoration: underline;
}

.contact-method a:hover {
    opacity: 0.7;
}

/* Contact Form */
.contact-form-wrapper {
    background: var(--color-bg-light);
    padding: var(--spacing-lg);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-accent);
}

.form-group input,
.form-group textarea {
    padding: 0.875rem;
    font-family: inherit;
    font-size: 0.9375rem;
    border: 1px solid var(--color-border);
    background: white;
    outline: none;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.05);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.btn-submit {
    padding: 1rem 2rem;
    font-size: 0.9375rem;
    font-weight: 500;
    color: white;
    background: var(--color-accent);
    border: none;
    transition: var(--transition);
    align-self: flex-start;
}

.btn-submit:hover {
    opacity: 0.85;
    transform: translateY(-2px);
}

.form-message {
    font-size: 0.875rem;
    padding: 0.75rem;
    border-radius: 4px;
    display: none;
}

.form-message.success {
    display: block;
    background: #e8f5e9;
    color: #2e7d32;
    border: 1px solid #a5d6a7;
}

.form-message.error {
    display: block;
    background: #ffebee;
    color: #c62828;
    border: 1px solid #ef9a9a;
}

/* Article Detail Page */
.article-detail {
    padding: var(--spacing-xl) 0;
}

.article-detail-header {
    max-width: 800px;
    margin: 0 auto var(--spacing-lg);
    text-align: center;
}

.article-detail-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--color-accent);
}

.article-detail-meta {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    font-size: 0.9375rem;
    color: var(--color-text-light);
}

.article-detail-featured {
    width: 100%;
    max-width: 1000px;
    margin: 0 auto var(--spacing-lg);
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: var(--color-bg-light);
}

.article-detail-featured img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

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

.article-body {
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--color-text);
}

.article-body h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin: var(--spacing-lg) 0 var(--spacing-md);
    color: var(--color-accent);
}

.article-body h3 {
    font-size: 1.375rem;
    font-weight: 600;
    margin: var(--spacing-md) 0 var(--spacing-sm);
    color: var(--color-accent);
}

.article-body p {
    margin-bottom: var(--spacing-md);
}

.article-body a {
    color: #0a56d6;
    text-decoration: underline;
    text-decoration-thickness: 2px;
    text-underline-offset: 3px;
    transition: color 0.2s ease, background-color 0.2s ease;
}

.article-body a:hover,
.article-body a:focus {
    color: #083ea3;
    background-color: rgba(10, 86, 214, 0.08);
    outline: none;
}

.article-body ul,
.article-body ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-md);
}

.article-body li {
    margin-bottom: var(--spacing-xs);
}

.article-body img {
    width: 100%;
    margin: var(--spacing-lg) 0;
    border-radius: 0;
}

.article-body blockquote {
    margin: var(--spacing-lg) 0;
    padding-left: var(--spacing-md);
    border-left: 3px solid var(--color-accent);
    font-style: italic;
    color: var(--color-text-light);
}

/* Product Card */
.product-card {
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-md);
    background: var(--color-bg-light);
    border: 1px solid var(--color-border);
}

.product-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--color-accent);
}

.product-info {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.product-image {
    width: 200px;
    height: 200px;
    background: white;
    overflow: hidden;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.product-details h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--color-accent);
}

.product-details p {
    font-size: 0.9375rem;
    line-height: 1.6;
    color: var(--color-text-light);
}

.product-rating {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    margin: var(--spacing-sm) 0;
    font-size: 0.875rem;
}

.stars {
    color: #ffa500;
}

.product-features {
    margin: var(--spacing-sm) 0;
}

.product-features ul {
    list-style-position: inside;
    padding: 0;
}

.product-price {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-accent);
    margin: var(--spacing-sm) 0;
}

/* Loading Indicator */
.articles-loader {
    grid-column: 1/-1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 4rem 0;
    gap: 1rem;
}

.loader-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--color-bg-light);
    border-top: 4px solid var(--color-accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

.articles-loader p {
    color: var(--color-text-light);
    font-size: 0.9375rem;
}

/* Skeleton Loading for Article Cards */
.article-card.skeleton {
    pointer-events: none;
}

.article-card.skeleton .article-image,
.article-card.skeleton .article-title,
.article-card.skeleton .article-excerpt {
    background: linear-gradient(
        90deg,
        #f0f0f0 25%,
        #e0e0e0 50%,
        #f0f0f0 75%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    color: transparent;
    border-radius: 4px;
}

.article-card.skeleton .article-title {
    height: 1.5rem;
    margin-bottom: 0.5rem;
}

.article-card.skeleton .article-excerpt {
    height: 3rem;
}

/* Footer */
.footer {
    background: var(--color-accent);
    color: white;
    padding: var(--spacing-xl) 0 var(--spacing-md);
    margin-top: var(--spacing-xl);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section h3,
.footer-section h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    font-size: 0.9375rem;
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.7);
}

.footer-brand {
    grid-column: span 1;
}

.footer-brand p {
    margin-top: var(--spacing-sm);
}

/* Footer Links */
.footer-links {
    list-style: none;
    padding: 0;
    margin: 0;
}

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

.footer-links a {
    font-size: 0.9375rem;
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition);
    display: inline-block;
}

.footer-links a:hover {
    color: white;
    transform: translateX(3px);
}

/* Newsletter Form */
.footer-newsletter-text {
    font-size: 0.875rem;
    margin-bottom: var(--spacing-md);
}

.footer-newsletter-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.footer-newsletter-form input {
    padding: 0.75rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 0.875rem;
    outline: none;
    transition: var(--transition);
}

.footer-newsletter-form input::placeholder {
    color: rgba(255, 255, 255, 0.5);
}

.footer-newsletter-form input:focus {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.4);
}

.footer-newsletter-form button {
    padding: 0.75rem;
    background: white;
    color: var(--color-accent);
    font-size: 0.875rem;
    font-weight: 500;
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

.footer-newsletter-form button:hover {
    background: rgba(255, 255, 255, 0.9);
    transform: translateY(-1px);
}

/* Footer Social Section */
.footer-social-section {
    margin-top: var(--spacing-md);
}

.footer-social-section p {
    font-size: 0.875rem;
    margin-bottom: var(--spacing-sm);
    color: rgba(255, 255, 255, 0.7);
}

.social-icons {
    display: flex;
    gap: var(--spacing-xs);
}

.social-icons a {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.social-icons a:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
}

.footer-bottom p {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
}

/* Animations */
.fade-in {
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
    }

    .nav-menu {
        position: fixed;
        top: 73px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: var(--spacing-md);
        gap: var(--spacing-sm);
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        transition: var(--transition);
        pointer-events: none;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: all;
    }

    .menu-toggle {
        display: flex;
    }

    .menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translateY(10px);
    }

    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translateY(-10px);
    }

    .articles-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .category-filter {
        flex-direction: column;
    }

    .category-btn {
        width: 100%;
        text-align: center;
    }

    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }

    .product-info {
        grid-template-columns: 1fr;
    }

    .product-image {
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .article-detail-meta {
        flex-direction: column;
        gap: var(--spacing-xs);
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }

    .container {
        padding: 0 var(--spacing-sm);
    }
}

/* Print Styles */
@media print {
    .header,
    .search-section,
    .categories,
    .footer {
        display: none;
    }
}

/* ===================================
   UI Enhancements
   =================================== */

/* Reading Progress Bar */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    z-index: 10000;
    transition: width 0.1s ease-out;
    box-shadow: 0 2px 4px rgba(102, 126, 234, 0.3);
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 9999;
}

.back-to-top:hover {
    background: var(--color-accent);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.back-to-top:active {
    transform: translateY(0);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top svg {
    width: 20px;
    height: 20px;
}

/* Mobile adjustments */
@media (max-width: 768px) {
    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
    }

    .reading-progress {
        height: 2px;
    }
}