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

html {
  scroll-behavior: smooth;
}

:root {
  /* 2016 Flat Design Color Palette */
  --turquoise: #1abc9c;
  --emerald: #2ecc71;
  --peter-river: #3498db;
  --amethyst: #9b59b6;
  --wet-asphalt: #34495e;
  --sun-flower: #f1c40f;
  --carrot: #e67e22;
  --alizarin: #e74c3c;
  --clouds: #ecf0f1;
  --midnight: #2c3e50;

  --primary: var(--peter-river);
  --secondary: var(--turquoise);
  --accent: var(--sun-flower);
  --dark: var(--midnight);
  --light: var(--clouds);
}

body {
  font-family: "Open Sans", sans-serif;
  background: var(--light);
  color: var(--dark);
  overflow-x: hidden;
}

/* =====================
   INTRO NAVIGATION - 2016 Style
   ===================== */
.intro-nav {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  padding: 1rem 2rem;
  z-index: 100;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.intro-logo {
  font-family: "Montserrat", sans-serif;
  font-weight: 900;
  font-size: 1.5rem;
  color: #F8F4EC;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.intro-logo-icon {
  width: 40px;
  height: 40px;
  background: var(--primary);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: #F8F4EC;
  font-weight: 900;
}

.intro-nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.intro-nav-links a {
  color: #F8F4EC;
  text-decoration: none;
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.85rem;
  letter-spacing: 1px;
  transition: color 0.3s ease;
  position: relative;
}

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

.intro-nav-links a::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--accent);
  transition: width 0.3s ease;
}

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

/* =====================
   INTRODUCTION PAGE
   ===================== */
.intro-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem;
  background: url("back.gif") center center / cover no-repeat;
  position: relative;
  overflow: hidden;
}

.intro-page::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    135deg,
    rgba(44, 62, 80, 0.3) 0%,
    rgba(44, 62, 80, 0.4) 100%
  );
  z-index: 1;
}

.intro-page::after {
  content: "";
  position: absolute;
  bottom: -30%;
  right: -15%;
  width: 400px;
  height: 400px;
  background: var(--accent);
  border-radius: 50%;
  opacity: 0.1;
  animation: float 10s ease-in-out infinite reverse;
}

.intro-content {
  max-width: 800px;
  text-align: center;
  position: relative;
  z-index: 3;
  flex: 1;
}

.intro-year {
  font-family: "Montserrat", sans-serif;
  font-size: 8rem;
  font-weight: 900;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 1rem;
  text-shadow: 0 0 40px rgba(241, 196, 15, 0.3);
}

.intro-title {
  font-family: "Montserrat", sans-serif;
  font-size: 3.5rem;
  font-weight: 900;
  color: #F8F4EC;
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 3px;
}

.intro-subtitle {
  font-size: 1.4rem;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 2rem;
  font-weight: 600;
}

.intro-description {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.8;
  margin-bottom: 1.5rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.intro-tagline {
  font-family: "Montserrat", sans-serif;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--turquoise);
  margin-bottom: 3rem;
  font-style: italic;
}

.explore-btn {
  font-size: 1.2rem;
  padding: 1.5rem 3rem;
  background: var(--accent);
  color: var(--dark);
  border: none;
  cursor: pointer;
  transition: all 0.4s ease;
  font-family: "Montserrat", sans-serif;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 2px;
  position: relative;
  overflow: hidden;
}

.explore-btn::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.3),
    transparent
  );
  transition: left 0.6s ease;
}

.explore-btn:hover::before {
  left: 100%;
}

.explore-btn:hover {
  background: #d4ac0d;
  transform: translateY(-5px);
  box-shadow: 0 20px 50px rgba(241, 196, 15, 0.4);
}

.intro-visual {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
  z-index: 1;
}

.floating-icons {
  position: relative;
  width: 100%;
  height: 100%;
}

/* Intro page responsive */
@media (max-width: 900px) {
  .intro-page {
    padding: 4rem 1rem 2rem;
  }

  .intro-year {
    font-size: 5rem;
  }

  .intro-title {
    font-size: 2.5rem;
  }

  .intro-subtitle {
    font-size: 1.1rem;
  }

  .intro-description {
    font-size: 1rem;
  }

  .explore-btn {
    font-size: 1rem;
    padding: 1.2rem 2.5rem;
  }
}

/* =====================
   HERO SECTION
   ===================== */
.hero {
  min-height: 120vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem 6rem;
  position: relative;
  overflow: hidden;
  background: url("back_new.png") center center / cover no-repeat;
  background-attachment: scroll;
}

/* Dark overlay for better contrast */
.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.3);
  z-index: 1;
}

/* Geometric shapes removed - using background image instead */

.hero-content {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Hero text styles removed - using only interactive book */

/* Flat Design Buttons - Classic 2016 */
.btn {
  display: inline-block;
  padding: 1rem 2.5rem;
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  font-size: 0.9rem;
}

.btn-primary {
  background: var(--primary);
  color: #F8F4EC;
}

.btn-primary:hover {
  background: #2980b9;
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(52, 152, 219, 0.4);
}

.btn-secondary {
  background: transparent;
  color: var(--dark);
  border: 3px solid var(--dark);
}

.btn-secondary:hover {
  background: var(--dark);
  color: #F8F4EC;
  transform: translateY(-3px);
}

/* Book Mockup - Centered in hero */

.book-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.book-mockup {
  width: 480px;
  height: 640px;
  position: relative;
  perspective: 1500px;
}

.book-page {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--dark) 0%, var(--wet-asphalt) 100%);
  border-radius: 0 15px 15px 0;
  box-shadow: -8px 0 0 var(--primary), 0 20px 50px rgba(0, 0, 0, 0.3);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 2rem;
  text-align: center;
  transform-origin: left center;
  transition: all 0.6s cubic-bezier(0.645, 0.045, 0.355, 1);
  backface-visibility: hidden;
  opacity: 0;
  transform: rotateY(-30deg);
  pointer-events: none;
}

.book-page::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 15px;
  background: linear-gradient(to right, rgba(0, 0, 0, 0.3), transparent);
  border-radius: 0 0 0 0;
}

.book-page.active {
  opacity: 1;
  transform: rotateY(0deg);
  pointer-events: auto;
  z-index: 10;
}

.book-page.prev {
  opacity: 0;
  transform: rotateY(30deg);
  z-index: 5;
}

.book-page.next {
  opacity: 0;
  transform: rotateY(-30deg);
  z-index: 5;
}

/* Cover Styles */
.book-page.cover {
  background: linear-gradient(135deg, var(--dark) 0%, #1a252f 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 0;
  position: relative;
  overflow: hidden;
}

.book-page.cover::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 20px;
  background: linear-gradient(
    to right,
    rgba(0, 0, 0, 0.4) 0%,
    rgba(0, 0, 0, 0.2) 50%,
    rgba(0, 0, 0, 0.1) 100%
  );
  z-index: 15;
  border-radius: 0;
}

.book-page.cover::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    135deg,
    transparent 0%,
    rgba(255, 255, 255, 0.1) 30%,
    transparent 70%,
    rgba(0, 0, 0, 0.1) 100%
  );
  z-index: 12;
  pointer-events: none;
}

.book-cover-image {
  width: calc(100% - 8px);
  height: calc(100% - 8px);
  object-fit: cover;
  object-position: center center;
  border-radius: 0 12px 12px 0;
  filter: brightness(1.05) contrast(1.15) saturate(1.1);
  transition: all 0.3s ease;
  margin: 4px 4px 4px 0;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.2),
    inset 0 0 20px rgba(0, 0, 0, 0.1);
}

.book-year {
  font-family: "Montserrat", sans-serif;
  font-size: 5rem;
  font-weight: 900;
  color: var(--accent);
  line-height: 1;
}

.book-title {
  font-family: "Montserrat", sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: #F8F4EC;
  text-transform: uppercase;
  letter-spacing: 3px;
  margin-top: 1rem;
}

.book-subtitle {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.7);
  margin-top: 0.5rem;
}

.book-page.cover .page-hint {
  position: absolute;
  bottom: 1.5rem;
  right: 2rem;
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.95);
  animation: pulse 2s ease-in-out infinite;
  z-index: 20;
  background: linear-gradient(135deg, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0.6));
  padding: 0.4rem 0.8rem;
  border-radius: 15px;
  backdrop-filter: blur(8px);
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

@keyframes pulse {
  0%,
  100% {
    opacity: 0.5;
  }
  50% {
    opacity: 1;
  }
}

/* Inner Page Styles */
.book-page.page-1,
.book-page.page-2 {
  background: #f5f0e8;
  color: var(--dark);
  justify-content: flex-start;
  padding-top: 3rem;
}

.book-page.page-1::before,
.book-page.page-2::before,
.book-page.page-3::before {
  background: linear-gradient(to right, rgba(0, 0, 0, 0.1), transparent);
}

.page-header {
  font-family: "Montserrat", sans-serif;
  font-size: 1.3rem;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--primary);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--primary);
  width: 100%;
}

.page-content {
  text-align: left;
  flex: 1;
}

.page-content p {
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 1rem;
  color: var(--wet-asphalt);
}

.drop-cap::first-letter {
  font-size: 3rem;
  font-family: "Montserrat", sans-serif;
  font-weight: 900;
  float: left;
  line-height: 1;
  margin-right: 0.5rem;
  color: var(--primary);
}

.toc-list {
  list-style: none;
  text-align: left;
}

.toc-list li {
  padding: 0.8rem 0;
  border-bottom: 1px dashed rgba(0, 0, 0, 0.1);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.toc-icon {
  font-size: 1.3rem;
}

.page-number {
  position: absolute;
  bottom: 1.5rem;
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  color: rgba(0, 0, 0, 0.3);
}


.book-page.page-3 {
  padding: 0;
}

.book-last-page-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center center;
  border-radius: 0 15px 15px 0;
  display: block;
}


/* Book Controls */
.book-controls {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.page-nav {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: 3px solid var(--dark);
  background: white;
  font-size: 1.2rem;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-nav:hover {
  background: var(--dark);
  color: #F8F4EC;
  transform: scale(1.1);
}

.page-nav.buy-now {
  background: var(--accent);
  border-color: var(--accent);
  animation: pulse 1.5s ease-in-out infinite;
}

.page-indicator {
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--wet-asphalt);
}

/* Book Buy Section */
.book-buy-section {
  margin-top: 2rem;
  text-align: center;
}

.book-buy-btn {
  padding: 1.2rem 2.5rem;
  font-size: 1.1rem;
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  background: var(--accent);
  color: var(--dark);
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 1px;
  border-radius: 5px;
  transition: all 0.3s ease;
  box-shadow: 0 5px 20px rgba(241, 196, 15, 0.3);
}

.book-buy-btn:hover {
  background: #d4ac0d;
  transform: translateY(-3px);
  box-shadow: 0 15px 35px rgba(241, 196, 15, 0.5);
  color: var(--dark);
  text-decoration: none;
}

/* =====================
   CATEGORIES SECTION
   ===================== */
.categories-section {
  padding: 5rem 2rem;
  background: url("category_back.png") center center / cover no-repeat;
  text-align: center;
  position: relative;
}

.categories-cta h2 {
  font-family: "Montserrat", sans-serif;
  font-size: 2rem;
  font-weight: 900;
  color: var(--dark);
  margin-bottom: 0.5rem;
  text-align: center;
}

.categories-subtitle {
  color: var(--wet-asphalt);
  text-align: center;
  margin-bottom: 2rem;
  font-size: 1.1rem;
}

.category-names {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 3rem;
  flex-wrap: wrap;
}

.category-name {
  font-family: "Montserrat", sans-serif;
  font-size: 1.2rem;
  font-weight: 700;
  padding: 1rem 2rem;
  background: transparent;
  border: 3px solid var(--dark);
  color: var(--dark);
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.3s ease;
  border-radius: 0;
}

.category-name:hover {
  background: var(--dark);
  color: #F8F4EC;
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.category-name.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #F8F4EC;
}

/* Sub-filters styling */
.sub-filters {
  margin: 2rem auto;
  text-align: center;
  max-width: 800px;
  opacity: 0;
  transform: translateY(-10px);
  transition: all 0.3s ease;
}

.sub-filters.show {
  opacity: 1;
  transform: translateY(0);
}

.sub-filter-label {
  font-family: "Montserrat", sans-serif;
  font-size: 1rem;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.sub-filter-buttons {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.sub-filter-name {
  font-family: "Montserrat", sans-serif;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  background: rgba(255, 255, 255, 0.9);
  border: 2px solid var(--wet-asphalt);
  color: var(--wet-asphalt);
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.3s ease;
  border-radius: 25px;
}

.sub-filter-name:hover {
  background: var(--wet-asphalt);
  color: #F8F4EC;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.sub-filter-name.active {
  background: var(--turquoise);
  border-color: var(--turquoise);
  color: #F8F4EC;
  box-shadow: 0 5px 15px rgba(26, 188, 156, 0.3);
}

/* Product Widget */
.product-widget {
  max-width: 1400px;
  margin: 2rem auto 0;
  background: transparent;
  padding: 2rem;
  opacity: 1;
  transform: translateY(0);
  transition: all 0.3s ease;
}

.widget-header {
  text-align: center;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 3px solid white;
}

.widget-header h3 {
  font-family: "Montserrat", sans-serif;
  font-size: 2.2rem;
  font-weight: 900;
  color: #F8F4EC;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin: 0;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.widget-close {
  width: 40px;
  height: 40px;
  background: transparent;
  border: 2px solid var(--dark);
  font-size: 1.2rem;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
}

.widget-close:hover {
  background: var(--dark);
  color: #F8F4EC;
  transform: rotate(90deg);
}

/* Products Grid - Always 3 columns */
.widget-products {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  margin: 0 auto;
}

.widget-products .product-card {
  grid-column: span 1;
  grid-row: span 1;
  background: #F8F4EC;
  border-radius: 15px;
  padding: 2rem;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
  border: 3px solid transparent;
  min-height: 300px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.widget-products .product-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.25);
  border-color: var(--primary);
}

.widget-products .product-image {
  font-size: 4rem;
  margin-bottom: 1.5rem;
  height: 120px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.widget-products .product-card h3 {
  font-family: "Montserrat", sans-serif;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 1rem;
  line-height: 1.4;
}

.widget-products .product-card .price {
  font-family: "Montserrat", sans-serif;
  font-size: 1.3rem;
  font-weight: 900;
  color: var(--primary);
  margin-bottom: 1.5rem;
}

.widget-products .buy-widget {
  background: var(--primary);
  color: #F8F4EC;
  padding: 1rem 1.5rem;
  border-radius: 8px;
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  text-decoration: none;
  transition: all 0.3s ease;
  margin-top: auto;
}

.widget-products .buy-widget:hover {
  background: #2980b9;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(52, 152, 219, 0.4);
  text-decoration: none;
  color: #F8F4EC;
}

/* =====================
   CATEGORIES POPUP
   ===================== */
.popup-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(44, 62, 80, 0.95);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  opacity: 0;
  visibility: hidden;
  transition: all 0.4s ease;
}

.popup-overlay.active {
  opacity: 1;
  visibility: visible;
}

.popup-content {
  background: var(--light);
  padding: 3rem;
  border-radius: 8px;
  max-width: 700px;
  width: 100%;
  position: relative;
  transform: scale(0.8) translateY(50px);
  transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.popup-overlay.active .popup-content {
  transform: scale(1) translateY(0);
}

.popup-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 40px;
  height: 40px;
  background: transparent;
  border: 2px solid var(--dark);
  font-size: 1.2rem;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.popup-close:hover {
  background: var(--dark);
  color: #F8F4EC;
}

.popup-title {
  font-family: "Montserrat", sans-serif;
  font-size: 2rem;
  font-weight: 900;
  color: var(--dark);
  margin-bottom: 0.5rem;
  text-align: center;
}

.popup-subtitle {
  color: var(--wet-asphalt);
  text-align: center;
  margin-bottom: 2rem;
}

.popup-content .category-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-bottom: 2rem;
}

.popup-content .category-card {
  padding: 1.5rem;
  text-align: center;
  border-radius: 8px;
  transition: all 0.3s ease;
  cursor: pointer;
}

.popup-content .category-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.popup-content .category-card.gaming {
  background: var(--alizarin);
  color: #F8F4EC;
}

.popup-content .category-card.tech {
  background: var(--primary);
  color: #F8F4EC;
}

.popup-content .category-card.fashion {
  background: var(--amethyst);
  color: #F8F4EC;
}

.popup-content .category-card.music {
  background: var(--turquoise);
  color: #F8F4EC;
}

.popup-content .category-icon {
  font-size: 2.5rem;
  margin-bottom: 0.75rem;
}

.popup-content .category-card h3 {
  font-family: "Montserrat", sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 0.25rem;
}

.popup-content .category-card p {
  font-size: 0.8rem;
  opacity: 0.85;
}

.popup-cta {
  display: block;
  width: 100%;
  text-align: center;
}


/* =====================
   RESPONSIVE
   ===================== */
@media (max-width: 900px) {
  .nav-links {
    display: none;
  }

  .hero {
    padding: 4rem 1rem 2rem;
  }

  .book-mockup {
    width: 360px;
    height: 480px;
  }

  .book-year {
    font-size: 4rem;
  }

  .book-page {
    padding: 1.5rem;
  }

  .page-header {
    font-size: 1.1rem;
  }

  .page-content p {
    font-size: 0.85rem;
  }

  .categories-cta h2 {
    font-size: 1.5rem;
  }

  .category-names {
    gap: 1rem;
  }

  .category-name {
    font-size: 1rem;
    padding: 0.8rem 1.5rem;
  }

  .product-widget {
    padding: 1.5rem;
    margin: 0 1rem;
  }

  .widget-header h3 {
    font-size: 1.4rem;
  }

  .widget-products {
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
  }

  .widget-products .product-card {
    padding: 1.5rem;
    min-height: 250px;
  }

  .widget-products .product-image {
    font-size: 3rem;
    height: 80px;
    margin-bottom: 1rem;
  }

  .widget-products .product-card h3 {
    font-size: 1rem;
  }

  .widget-products .product-card .price {
    font-size: 1.1rem;
    margin-bottom: 1rem;
  }

  .widget-products .buy-widget {
    padding: 0.8rem 1rem;
    font-size: 0.8rem;
  }

  /* Sub-filters responsive */
  .sub-filter-buttons {
    gap: 0.5rem;
  }

  .sub-filter-name {
    font-size: 0.8rem;
    padding: 0.6rem 1.2rem;
  }
}

/* =====================
   ANIMATIONS
   ===================== */
@keyframes float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-20px);
  }
}

/* Subtle floating animation for the book */
.book-container {
  animation: float 8s ease-in-out infinite;
}