/* Converting from Tailwind to custom CSS with design system variables */
:root {
  /* Color System */
  --background: oklch(1 0 0);
  --foreground: oklch(0.145 0 0);
  --card: oklch(1 0 0);
  --card-foreground: oklch(0.145 0 0);
  --primary: oklch(0.205 0 0);
  --primary-foreground: oklch(0.985 0 0);
  --secondary: oklch(0.97 0 0);
  --secondary-foreground: oklch(0.205 0 0);
  --muted: oklch(0.97 0 0);
  --muted-foreground: oklch(0.556 0 0);
  --accent: oklch(0.97 0 0);
  --accent-foreground: oklch(0.205 0 0);
  --border: oklch(0.922 0 0);
  --input: oklch(0.922 0 0);
  --ring: oklch(0.708 0 0);
  --chart-1: oklch(0.646 0.222 41.116);
  --chart-2: oklch(0.6 0.118 184.704);
  --radius: 0.625rem;

  /* Typography */
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

  /* Spacing */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;
  --spacing-20: 5rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --background: oklch(0.145 0 0);
    --foreground: oklch(0.985 0 0);
    --card: oklch(0.145 0 0);
    --card-foreground: oklch(0.985 0 0);
    --primary: oklch(0.985 0 0);
    --primary-foreground: oklch(0.205 0 0);
    --secondary: oklch(0.269 0 0);
    --secondary-foreground: oklch(0.985 0 0);
    --muted: oklch(0.269 0 0);
    --muted-foreground: oklch(0.708 0 0);
    --accent: oklch(0.269 0 0);
    --accent-foreground: oklch(0.985 0 0);
    --border: oklch(0.269 0 0);
    --input: oklch(0.269 0 0);
    --ring: oklch(0.439 0 0);
    --chart-1: oklch(0.488 0.243 264.376);
    --chart-2: oklch(0.696 0.17 162.48);
  }
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--background);
  color: var(--foreground);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.page-container {
  min-height: 100vh;
  background: linear-gradient(135deg, var(--background) 0%, var(--background) 60%, var(--muted) 100%);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-4);
}

/* Navigation */
.navbar {
  border-bottom: 1px solid color-mix(in oklch, var(--border) 40%, transparent);
  backdrop-filter: blur(8px);
  background-color: color-mix(in oklch, var(--background) 80%, transparent);
  position: sticky;
  top: 0;
  z-index: 50;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-4);
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 4rem;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.brand-icon {
  width: 2rem;
  height: 2rem;
  color: var(--primary);
}

.brand-text {
  font-size: 1.25rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--foreground), var(--muted-foreground));
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-4);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-2);
  padding: var(--spacing-2) var(--spacing-4);
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}

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

.btn-primary:hover {
  background-color: color-mix(in oklch, var(--primary) 90%, black);
}

.btn-ghost {
  color: var(--muted-foreground);
}

.btn-ghost:hover {
  color: var(--foreground);
}

.btn-outline {
  border: 1px solid var(--border);
  background-color: transparent;
  color: var(--foreground);
}

.btn-outline:hover {
  background-color: var(--accent);
}

.btn-large {
  padding: var(--spacing-6) var(--spacing-8);
  font-size: 1.125rem;
  font-weight: 600;
}

.btn-icon {
  width: 1.25rem;
  height: 1.25rem;
  transition: transform 0.2s ease;
}

.btn:hover .btn-icon {
  transform: translateX(2px);
}

/* Hero Section */
.hero-section {
  padding: var(--spacing-20) var(--spacing-4);
}

.hero-content {
  text-align: center;
  max-width: 1200px;
  margin: 0 auto;
}

.hero-text {
  margin-bottom: var(--spacing-8);
}

.badge {
  display: inline-block;
  padding: var(--spacing-2) var(--spacing-4);
  background-color: var(--secondary);
  color: var(--secondary-foreground);
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: var(--spacing-4);
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: var(--spacing-4);
}

.gradient-text {
  background: linear-gradient(135deg, var(--primary), var(--chart-1), var(--chart-2));
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: 1.25rem;
  color: var(--muted-foreground);
  max-width: 600px;
  margin: 0 auto var(--spacing-8);
}

.hero-actions {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
  align-items: center;
}

@media (min-width: 640px) {
  .hero-actions {
    flex-direction: row;
    justify-content: center;
  }
}

/* Sections */
.features-section,
.featured-books-section {
  padding: var(--spacing-20) var(--spacing-4);
  background-color: color-mix(in oklch, var(--muted) 30%, transparent);
}

.how-it-works-section,
.cta-section {
  padding: var(--spacing-20) var(--spacing-4);
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-16);
}

.section-title {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: var(--spacing-4);
}

.section-description {
  font-size: 1.125rem;
  color: var(--muted-foreground);
  max-width: 600px;
  margin: 0 auto;
}

/* Feature Cards */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-8);
}

.feature-card {
  background-color: color-mix(in oklch, var(--card) 50%, transparent);
  border: 1px solid color-mix(in oklch, var(--border) 50%, transparent);
  border-radius: var(--radius);
  padding: var(--spacing-6);
  text-align: center;
  backdrop-filter: blur(4px);
  transition: all 0.3s ease;
}

.feature-card:hover {
  background-color: color-mix(in oklch, var(--card) 80%, transparent);
  transform: translateY(-2px);
}

.feature-icon {
  width: 3rem;
  height: 3rem;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-4);
  transition: all 0.3s ease;
}

.search-icon {
  background-color: color-mix(in oklch, var(--primary) 10%, transparent);
  color: var(--primary);
}

.users-icon {
  background-color: color-mix(in oklch, var(--chart-1) 10%, transparent);
  color: var(--chart-1);
}

.heart-icon {
  background-color: color-mix(in oklch, var(--chart-2) 10%, transparent);
  color: var(--chart-2);
}

.feature-card:hover .feature-icon {
  background-color: color-mix(in oklch, var(--primary) 20%, transparent);
}

.feature-icon svg {
  width: 1.5rem;
  height: 1.5rem;
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--spacing-2);
}

.feature-description {
  color: var(--muted-foreground);
}

/* Steps */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-8);
}

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

.step-number {
  width: 4rem;
  height: 4rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--chart-1));
  color: var(--primary-foreground);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.125rem;
  font-weight: 700;
  margin: 0 auto var(--spacing-4);
}

.step-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--spacing-4);
}

.step-description {
  color: var(--muted-foreground);
}

/* Books Grid */
.books-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-6);
}

.book-card {
  background-color: color-mix(in oklch, var(--card) 50%, transparent);
  border: 1px solid color-mix(in oklch, var(--border) 50%, transparent);
  border-radius: var(--radius);
  padding: var(--spacing-4);
  backdrop-filter: blur(4px);
  transition: all 0.3s ease;
  cursor: pointer;
}

.book-card:hover {
  background-color: color-mix(in oklch, var(--card) 80%, transparent);
  transform: translateY(-2px);
}

.book-cover {
  aspect-ratio: 3 / 4;
  background: linear-gradient(135deg, var(--muted), color-mix(in oklch, var(--muted) 50%, transparent));
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--spacing-4);
}

.book-cover svg {
  width: 2rem;
  height: 2rem;
  color: var(--muted-foreground);
}

.book-genre {
  display: inline-block;
  padding: var(--spacing-1) var(--spacing-2);
  background-color: transparent;
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) - 2px);
  font-size: 0.75rem;
  margin-bottom: var(--spacing-2);
}

.book-title {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: var(--spacing-1);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.book-author {
  font-size: 0.75rem;
  color: var(--muted-foreground);
  margin-bottom: var(--spacing-2);
}

.book-rating {
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
}

.star-icon {
  width: 0.75rem;
  height: 0.75rem;
  color: #fbbf24;
}

.book-rating span {
  font-size: 0.75rem;
  font-weight: 500;
}

/* CTA Section */
.cta-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.cta-title {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: var(--spacing-4);
}

.cta-description {
  font-size: 1.125rem;
  color: var(--muted-foreground);
  margin-bottom: var(--spacing-8);
}

/* Footer */
.footer {
  border-top: 1px solid color-mix(in oklch, var(--border) 40%, transparent);
  background-color: color-mix(in oklch, var(--muted) 30%, transparent);
  padding: var(--spacing-12) var(--spacing-4);
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-8);
}

@media (min-width: 768px) {
  .footer-content {
    grid-template-columns: 2fr 3fr;
  }
}

.footer-brand {
  margin-bottom: var(--spacing-4);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  margin-bottom: var(--spacing-4);
}

.footer-description {
  font-size: 0.875rem;
  color: var(--muted-foreground);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-8);
}

.footer-title {
  font-weight: 600;
  margin-bottom: var(--spacing-4);
}

.footer-link-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
}

.footer-link {
  font-size: 0.875rem;
  color: var(--muted-foreground);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-link:hover {
  color: var(--foreground);
}

.footer-bottom {
  border-top: 1px solid color-mix(in oklch, var(--border) 40%, transparent);
  margin-top: var(--spacing-8);
  padding-top: var(--spacing-8);
  text-align: center;
}

.footer-copyright {
  font-size: 0.875rem;
  color: var(--muted-foreground);
}

/* Responsive Design */
@media (max-width: 640px) {
  .nav-actions {
    gap: var(--spacing-2);
  }

  .btn {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: 0.8rem;
  }

  .hero-section {
    padding: var(--spacing-12) var(--spacing-4);
  }

  .features-section,
  .how-it-works-section,
  .featured-books-section,
  .cta-section {
    padding: var(--spacing-12) var(--spacing-4);
  }
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* Focus styles for accessibility */
.btn:focus,
.footer-link:focus {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
}