/* ============================================
   Infinity Stone Works - Modern Design System
   ============================================ */

/* CSS Variables (Design Tokens) */
:root {
  /* Colors - Warm Minimalism Palette */
  --color-primary: #2C2C2C;           /* Warm Charcoal */
  --color-secondary: #8B9479;          /* Muted Olive */
  --color-accent: #C9B8A3;             /* Warm Taupe */

  --color-bg-primary: #FAF8F5;         /* Warm Cream */
  --color-bg-secondary: #E8E4DF;       /* Warm Gray */
  --color-bg-white: #FFFFFF;

  --color-text-primary: #1A1A1A;       /* Rich Black */
  --color-text-secondary: #666666;
  --color-text-light: #999999;

  /* Typography */
  --font-heading: 'Cormorant Garamond', serif;
  --font-subheading: 'Josefin Sans', sans-serif;
  --font-body: 'Karla', sans-serif;

  /* Font Sizes */
  --font-size-hero: clamp(48px, 8vw, 64px);
  --font-size-h1: clamp(42px, 6vw, 56px);
  --font-size-h2: clamp(36px, 5vw, 42px);
  --font-size-h3: clamp(24px, 3vw, 28px);
  --font-size-h4: clamp(18px, 2vw, 20px);
  --font-size-body: clamp(16px, 1.5vw, 18px);
  --font-size-small: 14px;

  /* Spacing */
  --spacing-hero: clamp(120px, 15vw, 150px);
  --spacing-section: clamp(80px, 10vw, 100px);
  --spacing-large: clamp(60px, 8vw, 80px);
  --spacing-medium: clamp(40px, 5vw, 60px);
  --spacing-small: clamp(20px, 3vw, 30px);
  --spacing-xs: 16px;

  /* Container */
  --container-max: 1400px;
  --container-text: 1200px;
  --container-padding: 40px;

  /* Border Radius */
  --radius-small: 4px;
  --radius-medium: 8px;
  --radius-large: 12px;

  /* Shadows */
  --shadow-small: 0 2px 12px rgba(0, 0, 0, 0.06);
  --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-large: 0 6px 24px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --transition-fast: 0.2s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  --transition-slow: 0.4s ease-in-out;

  /* Z-index */
  --z-navbar: 1000;
  --z-modal: 2000;
  --z-back-to-top: 900;
}

/* ============================================
   Reset & Base Styles
   ============================================ */

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

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

body {
  font-family: var(--font-body);
  font-size: var(--font-size-body);
  line-height: 1.7;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  overflow-x: hidden;
}

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

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

a:hover {
  color: var(--color-secondary);
}

ul {
  list-style: none;
}

/* ============================================
   Typography
   ============================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.2;
  color: var(--color-primary);
  margin-bottom: 1rem;
}

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

h2 {
  font-size: var(--font-size-h2);
}

h3 {
  font-size: var(--font-size-h3);
}

h4 {
  font-size: var(--font-size-h4);
}

p {
  margin-bottom: 1rem;
}

/* ============================================
   Container & Layout
   ============================================ */

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

@media (max-width: 768px) {
  .container {
    padding: 0 20px;
  }
}

section {
  padding: var(--spacing-section) 0;
}

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

.section-header h2 {
  margin-bottom: 1rem;
}

.section-header p {
  font-size: 18px;
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

.section-cta {
  text-align: center;
  margin-top: var(--spacing-medium);
}

/* ============================================
   Buttons
   ============================================ */

.btn {
  display: inline-block;
  padding: 16px 32px;
  font-family: var(--font-subheading);
  font-size: 16px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  border-radius: var(--radius-small);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-align: center;
}

.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-bg-white);
  border-color: var(--color-primary);
}

.btn-primary:hover {
  background-color: var(--color-secondary);
  border-color: var(--color-secondary);
  color: var(--color-bg-white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-medium);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.btn-secondary:hover {
  background-color: var(--color-primary);
  color: var(--color-bg-white);
  transform: translateY(-2px);
}

.btn-large {
  padding: 20px 40px;
  font-size: 18px;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* ============================================
   Navigation
   ============================================ */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: transparent;
  padding: 20px 0;
  transition: all var(--transition-normal);
  z-index: var(--z-navbar);
}

.navbar.scrolled {
  background-color: var(--color-primary);
  padding: 15px 0;
  box-shadow: var(--shadow-small);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo a {
  font-family: var(--font-heading);
  font-size: 28px;
  font-weight: 700;
  color: var(--color-bg-white);
  transition: color var(--transition-fast);
}

.nav-logo a:hover {
  color: var(--color-accent);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 30px;
}

.nav-link {
  font-family: var(--font-subheading);
  font-size: 16px;
  font-weight: 500;
  color: var(--color-bg-white);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-accent);
}

.nav-cta {
  padding: 12px 24px;
  font-size: 14px;
}

/* Mobile Navigation Toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 5px;
}

.nav-toggle span {
  display: block;
  width: 25px;
  height: 3px;
  background-color: var(--color-bg-white);
  transition: all var(--transition-fast);
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 400px;
    height: 100vh;
    background-color: var(--color-primary);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 40px;
    transition: right var(--transition-normal);
  }

  .nav-menu.active {
    right: 0;
  }

  .nav-link {
    font-size: 20px;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
  }

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

  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
  }
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  background: linear-gradient(135deg, #2C2C2C 0%, #3A4A52 100%);
  background-image: url('../images/hero-background.jpg');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  overflow: hidden;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.5));
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  padding: 0 20px;
  animation: fadeInUp 1s ease-out;
}

.hero-title {
  font-size: var(--font-size-hero);
  color: var(--color-bg-white);
  margin-bottom: 1rem;
  font-weight: 700;
}

.hero-subtitle {
  font-family: var(--font-subheading);
  font-size: clamp(24px, 4vw, 32px);
  color: var(--color-accent);
  margin-bottom: 1.5rem;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
}

.hero-description {
  font-size: clamp(18px, 2vw, 20px);
  color: var(--color-bg-white);
  margin-bottom: 2.5rem;
  opacity: 0.9;
}

.hero-cta {
  display: flex;
  gap: 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  color: var(--color-bg-white);
  font-size: 14px;
  letter-spacing: 1px;
  text-transform: uppercase;
  z-index: 2;
}

.scroll-indicator {
  width: 2px;
  height: 40px;
  background-color: var(--color-bg-white);
  margin: 10px auto 0;
  opacity: 0.6;
  animation: scrollBounce 2s infinite;
}

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

@keyframes scrollBounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(10px);
  }
}

@media (max-width: 768px) {
  .hero {
    background-attachment: scroll;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .hero-cta .btn {
    width: 100%;
    max-width: 300px;
  }
}

/* ============================================
   Collections Featured
   ============================================ */

.collections-featured {
  background-color: var(--color-bg-white);
}

.collections-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-bottom: var(--spacing-medium);
}

.collection-card {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-medium);
  box-shadow: var(--shadow-small);
  transition: all var(--transition-normal);
}

.collection-card:hover {
  box-shadow: var(--shadow-large);
  transform: translateY(-5px);
}

.collection-large {
  grid-column: span 2;
}

.collection-wide {
  grid-column: span 2;
}

@media (max-width: 968px) {
  .collection-large,
  .collection-wide {
    grid-column: span 1;
  }
}

.collection-image {
  position: relative;
  overflow: hidden;
  padding-top: 75%;
}

.collection-image img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

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

.collection-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.7));
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 30px;
  text-align: center;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.collection-card:hover .collection-overlay {
  opacity: 1;
}

.collection-overlay h3 {
  font-size: 32px;
  color: var(--color-bg-white);
  margin-bottom: 0.5rem;
}

.collection-overlay p {
  font-size: 18px;
  color: var(--color-bg-white);
  margin-bottom: 1.5rem;
  opacity: 0.9;
}

/* ============================================
   Why Choose Us / Features
   ============================================ */

.why-choose {
  background-color: var(--color-bg-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
}

.feature-card {
  text-align: center;
  padding: 40px 30px;
  background-color: var(--color-bg-white);
  border-radius: var(--radius-medium);
  transition: all var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-medium);
}

.feature-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-secondary);
}

.feature-card h3 {
  font-family: var(--font-subheading);
  font-size: 22px;
  margin-bottom: 1rem;
  color: var(--color-primary);
}

.feature-card p {
  color: var(--color-text-secondary);
  font-size: 16px;
  margin-bottom: 0;
}

/* ============================================
   Gallery
   ============================================ */

.gallery {
  background-color: var(--color-bg-white);
}

.gallery-filters {
  display: flex;
  justify-content: center;
  gap: 15px;
  flex-wrap: wrap;
  margin-bottom: var(--spacing-medium);
}

.filter-btn {
  padding: 12px 24px;
  font-family: var(--font-subheading);
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-small);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--color-primary);
  color: var(--color-bg-white);
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 30px;
  margin-bottom: var(--spacing-medium);
}

.gallery-item {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-medium);
  cursor: pointer;
  transition: all var(--transition-normal);
}

.gallery-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-large);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 4/3;
  transition: transform var(--transition-slow);
}

.gallery-item:hover img {
  transform: scale(1.1);
}

.gallery-item-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 20px;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  color: var(--color-bg-white);
  transform: translateY(100%);
  transition: transform var(--transition-normal);
}

.gallery-item:hover .gallery-item-overlay {
  transform: translateY(0);
}

.gallery-item-overlay h4 {
  font-size: 18px;
  color: var(--color-bg-white);
  margin-bottom: 0.25rem;
}

.gallery-item-overlay p {
  font-size: 14px;
  opacity: 0.9;
  margin-bottom: 0;
}

/* Gallery item hidden state (for filtering) */
.gallery-item.hidden {
  display: none;
}

/* ============================================
   Partners / Manufacturers
   ============================================ */

.partners {
  background-color: var(--color-bg-secondary);
}

/* .partners-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  align-items: center;
} */

.partners-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
  justify-content: center; /* centers rows */
  align-items: center;
}

.partners-grid > * {
  flex: 1 1 200px;
  max-width: 200px; /* optional but recommended */
}


.partner-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 30px;
  background-color: var(--color-bg-white);
  border-radius: var(--radius-medium);
  transition: all var(--transition-normal);
  min-height: 140px;
}

.partner-logo:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-medium);
}

.partner-logo img {
  max-width: 100%;
  max-height: 80px;
  width: auto;
  height: auto;
  filter: grayscale(100%);
  opacity: 0.7;
  transition: all var(--transition-normal);
}

.partner-logo:hover img {
  filter: grayscale(0%);
  opacity: 1;
}

@media (max-width: 768px) {
  .partners-grid {
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 20px;
  }

  .partner-logo {
    padding: 20px;
    min-height: 140px;
  }
}

/* ============================================
   Testimonials
   ============================================ */

.testimonials {
  background-color: var(--color-bg-white);
}

.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-bottom: var(--spacing-medium);
}

.testimonial-card {
  padding: 40px 30px;
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-medium);
  border-left: 4px solid var(--color-secondary);
  transition: all var(--transition-normal);
}

.testimonial-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-medium);
}

.testimonial-rating {
  color: var(--color-secondary);
  font-size: 20px;
  margin-bottom: 1rem;
  letter-spacing: 2px;
}

.testimonial-text {
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text-primary);
  font-style: italic;
  margin-bottom: 1.5rem;
}

.testimonial-author {
  border-top: 1px solid rgba(0, 0, 0, 0.1);
  padding-top: 1rem;
}

.author-name {
  font-family: var(--font-subheading);
  font-weight: 600;
  font-size: 16px;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.author-location {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

/* Skeleton loader for testimonials */
.testimonial-skeleton {
  padding: 40px 30px;
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: loading 1.5s infinite;
  border-radius: var(--radius-medium);
  height: 250px;
}

@keyframes loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

.testimonials-error {
  text-align: center;
  padding: 60px 20px;
}

.testimonials-error p {
  font-size: 18px;
  color: var(--color-text-secondary);
  margin-bottom: 2rem;
}

/* ============================================
   Contact Section
   ============================================ */

.contact {
  background-color: var(--color-bg-secondary);
}

.contact-wrapper {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 60px;
  align-items: start;
}

@media (max-width: 968px) {
  .contact-wrapper {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

.contact-info h2 {
  margin-bottom: 1rem;
}

.contact-info > p {
  color: var(--color-text-secondary);
  margin-bottom: 2rem;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.contact-detail {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.contact-detail svg {
  flex-shrink: 0;
  color: var(--color-secondary);
}

.contact-detail .detail-label {
  font-family: var(--font-subheading);
  font-weight: 600;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-text-secondary);
  margin-bottom: 0.5rem;
}

.contact-detail a {
  color: var(--color-primary);
  font-size: 18px;
}

.contact-detail a:hover {
  color: var(--color-secondary);
}

/* Forms */
.contact-form-wrapper,
.booking-form {
  background-color: var(--color-bg-white);
  padding: 40px;
  border-radius: var(--radius-medium);
  box-shadow: var(--shadow-small);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

@media (max-width: 768px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

.form-group label {
  display: block;
  font-family: var(--font-subheading);
  font-weight: 600;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--color-primary);
  margin-bottom: 0.5rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  font-family: var(--font-body);
  font-size: 16px;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  border: 2px solid transparent;
  border-radius: var(--radius-small);
  transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-secondary);
  background-color: var(--color-bg-white);
}

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

.form-message {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: var(--radius-small);
  font-size: 14px;
  text-align: center;
  display: none;
}

.form-message.success {
  display: block;
  background-color: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.form-message.error {
  display: block;
  background-color: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

/* ============================================
   Booking Section
   ============================================ */

.booking {
  background-color: var(--color-bg-white);
}

.booking-wrapper {
  max-width: 900px;
  margin: 0 auto;
}

.booking-header {
  text-align: center;
  margin-bottom: var(--spacing-medium);
}

.booking-header h2 {
  margin-bottom: 1rem;
}

.booking-header p {
  font-size: 18px;
  color: var(--color-text-secondary);
}

/* ============================================
   Footer
   ============================================ */

.footer {
  background-color: var(--color-primary);
  color: var(--color-bg-white);
  padding: var(--spacing-large) 0 30px;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
  margin-bottom: var(--spacing-medium);
}

.footer-column h3,
.footer-column h4 {
  color: var(--color-bg-white);
  margin-bottom: 1rem;
}

.footer-column h3 {
  font-size: 24px;
}

.footer-column h4 {
  font-family: var(--font-subheading);
  font-size: 16px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.footer-column p {
  color: var(--color-accent);
  font-size: 16px;
}

.footer-tagline {
  font-size: 14px !important;
  opacity: 0.8;
}

.footer-column ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-column ul li a {
  color: rgba(255, 255, 255, 0.8);
  transition: color var(--transition-fast);
}

.footer-column ul li a:hover {
  color: var(--color-accent);
}

.newsletter-form {
  display: flex;
  gap: 10px;
  margin-top: 1rem;
}

.newsletter-form input {
  flex: 1;
  padding: 12px 16px;
  font-size: 14px;
  border: none;
  border-radius: var(--radius-small);
}

.newsletter-form .btn {
  padding: 12px 20px;
  font-size: 14px;
}

@media (max-width: 768px) {
  .newsletter-form {
    flex-direction: column;
  }
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding-top: 30px;
  text-align: center;
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
  margin-bottom: 1rem;
}

.footer-partners span {
  color: rgba(255, 255, 255, 0.6);
  font-size: 12px;
}

/* ============================================
   Back to Top Button
   ============================================ */

.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  background-color: var(--color-secondary);
  color: var(--color-bg-white);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  z-index: var(--z-back-to-top);
  box-shadow: var(--shadow-medium);
}

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

.back-to-top:hover {
  background-color: var(--color-primary);
  transform: translateY(-5px);
}

/* ============================================
   Utility Classes
   ============================================ */

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

.mt-large {
  margin-top: var(--spacing-large);
}

.mb-large {
  margin-bottom: var(--spacing-large);
}

/* ============================================
   Animations
   ============================================ */

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

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

.slide-in-up {
  animation: slideInUp 0.6s ease-out;
}

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

/* Intersection Observer animations */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease-out;
}

.animate-on-scroll.animated {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   Lightbox
   ============================================ */

.lightbox {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.lightbox-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.9);
  cursor: pointer;
}

.lightbox-content {
  position: relative;
  max-width: 90%;
  max-height: 90vh;
  z-index: 1;
  animation: fadeInUp 0.3s ease-out;
}

.lightbox-content img {
  max-width: 100%;
  max-height: 80vh;
  border-radius: var(--radius-medium);
  box-shadow: var(--shadow-large);
}

.lightbox-close {
  position: absolute;
  top: -50px;
  right: 0;
  width: 40px;
  height: 40px;
  background-color: var(--color-bg-white);
  color: var(--color-primary);
  border: none;
  border-radius: 50%;
  font-size: 28px;
  line-height: 1;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.lightbox-close:hover {
  background-color: var(--color-secondary);
  color: var(--color-bg-white);
  transform: rotate(90deg);
}

.lightbox-caption {
  background-color: var(--color-bg-white);
  padding: 20px;
  border-radius: 0 0 var(--radius-medium) var(--radius-medium);
  margin-top: -4px;
}

.lightbox-caption h4 {
  margin-bottom: 0.5rem;
  color: var(--color-primary);
}

.lightbox-caption p {
  color: var(--color-text-secondary);
  font-size: 14px;
  margin-bottom: 0;
}

@media (max-width: 768px) {
  .lightbox-content {
    max-width: 95%;
  }

  .lightbox-close {
    top: 10px;
    right: 10px;
  }
}