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

:root {
  --color-primary: #031D34;
  --color-background: #EFEEEA;
  --color-text: #333333;
  --color-text-light: #666666;
  --color-accent: #1a4a6e;
  --color-border: #e0e0e0;
  --font-serif: 'Source Serif 4', Georgia, serif;
  --max-width: 1200px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 2.5rem;
  --spacing-xl: 3rem;
}

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

body {
  font-family: var(--font-serif);
  color: var(--color-text);
  background-color: var(--color-background);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

/* Typography */
h1, h2, h3, h4 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-primary);
}

h1 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: 1.875rem;
  margin-bottom: var(--spacing-sm);
}

h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
}

p {
  margin-bottom: var(--spacing-sm);
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

main {
  flex: 1;
}

/* Announcement Bar */
.announcement-bar {
  background-color: var(--color-primary);
  color: var(--color-background);
  text-align: center;
  padding: 0.75rem var(--spacing-md);
  font-size: 0.9375rem;
}

.announcement-bar strong {
  font-weight: 600;
}

/* Header & Navigation */
header {
  background-color: var(--color-background);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.logo {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-primary);
}

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

nav ul {
  display: flex;
  list-style: none;
  gap: var(--spacing-md);
}

nav a {
  font-size: 1rem;
  padding: var(--spacing-xs) 0;
  position: relative;
}

nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width 0.2s ease;
}

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

/* Mobile Navigation */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-primary);
  margin: 5px 0;
  transition: all 0.3s ease;
}

/* Hero Section */
.hero {
  padding: var(--spacing-lg) 0;
  position: relative;
  overflow: hidden;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  align-items: center;
}

.hero-text {
  max-width: 540px;
}

.hero-text h1 {
  font-size: 3rem;
  margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-sm);
  font-style: italic;
}

.hero-author {
  font-size: 1.125rem;
  color: var(--color-primary);
  margin-bottom: var(--spacing-md);
  font-weight: 600;
}

.hero-description {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.book-cover {
  max-width: 526px;
}

/* Curved Line Decoration */
.curve-decoration {
  position: absolute;
  width: 300px;
  height: 300px;
  pointer-events: none;
  opacity: 0.1;
}

.curve-decoration svg {
  width: 100%;
  height: 100%;
}

.curve-top-right {
  top: -50px;
  right: -50px;
}

.curve-bottom-left {
  bottom: -50px;
  left: -50px;
  transform: rotate(180deg);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 1rem 2rem;
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 600;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
  border: none;
}

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

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

.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

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

/* Waitlist Form */
.waitlist-form {
  display: flex;
  gap: var(--spacing-sm);
  max-width: 450px;
}

.waitlist-form input[type="email"] {
  flex: 1;
  padding: 1rem;
  font-family: var(--font-serif);
  font-size: 1rem;
  border: 2px solid var(--color-border);
  border-radius: 4px;
  outline: none;
  transition: border-color 0.2s ease;
}

.waitlist-form input[type="email"]:focus {
  border-color: var(--color-primary);
}

.waitlist-form button {
  white-space: nowrap;
}

.form-note {
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-top: var(--spacing-xs);
}

/* Page Sections */
.section {
  padding: var(--spacing-lg) 0;
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto var(--spacing-lg);
}

/* About Page */
.about-content {
  max-width: 700px;
  margin: 0 auto;
}

.about-content p {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.feature-card {
  padding: var(--spacing-md);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  transition: box-shadow 0.2s ease;
}

.feature-card:hover {
  box-shadow: 0 4px 20px rgba(3, 29, 52, 0.1);
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-xs);
}

.feature-card p {
  color: var(--color-text-light);
  margin-bottom: 0;
}

/* Chapters Page */
.chapters-toc {
  max-width: 800px;
  margin: 0 auto;
}

.part {
  margin-bottom: var(--spacing-lg);
}

.part-header {
  display: flex;
  align-items: baseline;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
  padding-bottom: var(--spacing-xs);
  border-bottom: 2px solid var(--color-primary);
}

.part-number {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-light);
}

.part-title {
  font-size: 1.5rem;
  margin-bottom: 0;
}

.part-description {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-sm);
  font-style: italic;
}

.chapter-list {
  list-style: none;
  padding-left: var(--spacing-md);
}

.chapter-list li {
  padding: var(--spacing-xs) 0;
  position: relative;
}

.chapter-list li::before {
  content: '—';
  position: absolute;
  left: -1.5rem;
  color: var(--color-text-light);
}

/* Author Page */
.author-section {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: var(--spacing-lg);
  max-width: 900px;
  margin: 0 auto;
  align-items: start;
}

.author-image {
  width: 100%;
  max-width: 300px;
}

.author-image img {
  width: 100%;
  border-radius: 8px;
}

.social-links {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-primary);
  color: var(--color-background);
  transition: background-color 0.2s ease;
}

.social-links a:hover {
  background-color: var(--color-accent);
}

.social-links svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

/* Footer social links - inverted colors */
footer .social-links a {
  background-color: rgba(255, 255, 255, 0.15);
  color: var(--color-background);
}

footer .social-links a:hover {
  background-color: rgba(255, 255, 255, 0.3);
}

.author-bio h2 {
  margin-bottom: var(--spacing-md);
}

.author-bio p {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-sm);
}

/* Footer */
footer {
  background-color: var(--color-primary);
  color: var(--color-background);
  padding: var(--spacing-lg) 0 var(--spacing-md);
  margin-top: auto;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
}

.footer-main h3 {
  color: var(--color-background);
  margin-bottom: var(--spacing-sm);
}

.footer-main p {
  opacity: 0.8;
  max-width: 400px;
}

.footer-links h4 {
  color: var(--color-background);
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
}

.footer-links ul {
  list-style: none;
}

.footer-links a {
  color: var(--color-background);
  opacity: 0.8;
  font-size: 0.9375rem;
}

.footer-links a:hover {
  opacity: 1;
  color: var(--color-background);
}

.footer-form {
  margin-top: var(--spacing-md);
}

.footer-form .waitlist-form {
  max-width: 100%;
}

.footer-form input[type="email"] {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.3);
  color: var(--color-background);
}

.footer-form input[type="email"]::placeholder {
  color: rgba(255, 255, 255, 0.6);
}

.footer-form input[type="email"]:focus {
  border-color: var(--color-background);
  background-color: rgba(255, 255, 255, 0.15);
}

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

.footer-form .btn:hover {
  background-color: rgba(255, 255, 255, 0.9);
}

.footer-bottom {
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  text-align: center;
  font-size: 0.875rem;
  opacity: 0.7;
}

/* Responsive Design */
@media (max-width: 1024px) {
  h1 {
    font-size: 2rem;
  }

  .hero-text h1 {
    font-size: 2.5rem;
  }

  .hero-content {
    gap: var(--spacing-md);
  }
}

@media (max-width: 768px) {
  :root {
    --spacing-lg: 2rem;
    --spacing-xl: 2.5rem;
  }

  .announcement-bar {
    font-size: 0.8125rem;
    padding: 0.5rem var(--spacing-sm);
  }

  .nav-toggle {
    display: block;
  }

  nav {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-md);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
  }

  nav.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  nav ul {
    flex-direction: column;
    gap: var(--spacing-sm);
  }

  .hero {
    padding: var(--spacing-lg) 0;
  }

  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
    gap: var(--spacing-sm);
  }

  .hero-text {
    max-width: 100%;
    order: 2;
  }

  .hero-text h1 {
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
  }

  .hero-subtitle {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
  }

  .hero-author {
    font-size: 1rem;
    margin-bottom: 0.75rem;
  }

  .hero-description {
    font-size: 1rem;
    margin-bottom: 1rem;
  }

  .hero-image {
    order: 1;
  }

  .book-cover {
    max-width: 330px;
  }

  .waitlist-form {
    flex-direction: column;
    max-width: 100%;
  }

  .author-section {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .author-image {
    margin: 0 auto;
  }

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

@media (max-width: 480px) {
  .hero-text h1 {
    font-size: 1.75rem;
  }

  .hero-subtitle {
    font-size: 1.125rem;
  }

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