/* Custom CSS Variables */
:root {
  --bg-color: #FAFAF7;
  --text-color: #1A1A1A;
  --accent-color: #1B365D; /* Muted dark blue accent */
  --muted-color: #71717A;  /* Lighter gray for status/meta */
  --border-color: #E4E4E7;  /* Clean separator borders */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-serif: 'Lora', Georgia, Cambria, "Times New Roman", Times, serif;
  --max-width: 640px;
}

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

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-serif);
  font-size: 18px;
  line-height: 1.625;
  padding: 4rem 1.5rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  color: var(--text-color);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

p {
  margin-bottom: 1.5rem;
  max-width: 70ch;
}

a {
  color: var(--accent-color);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}

a:hover {
  color: var(--text-color);
  text-decoration-color: var(--text-color);
}

/* Header & Navigation */
header {
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto 3rem auto;
}

.site-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1rem;
}

.nav-brand {
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--text-color);
}

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

.nav-links {
  display: flex;
  gap: 1.25rem;
  list-style: none;
}

.nav-links a {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 500;
  text-decoration: none;
  color: var(--muted-color);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-color);
}

/* Main Content Container */
main {
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  flex-grow: 1;
}

/* Home Page Hero Section */
.hero {
  text-align: center;
  padding: 4rem 0;
  margin-bottom: 2rem;
}

.author-name {
  font-size: 2.75rem;
  font-weight: 600;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.tagline {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 1.25rem;
  color: var(--muted-color);
  margin: 0 auto 2.5rem auto;
  max-width: 50ch;
}

.series-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 0.95rem;
}

.series-link {
  text-decoration: none;
  border-bottom: 1px solid var(--accent-color);
  padding-bottom: 2px;
}

.series-link:hover {
  border-bottom-color: var(--text-color);
}

.divider {
  color: var(--border-color);
  user-select: none;
}

/* Inner Page Title Header */
.page-title {
  font-size: 2.25rem;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

.page-description {
  font-size: 1.1rem;
  color: var(--muted-color);
  margin-bottom: 3rem;
  max-width: 60ch;
}

/* Dynamic Order Lists for Books */
.book-list {
  list-style: none;
  margin-bottom: 4rem;
  counter-reset: book-counter;
}

.book-list li {
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border-color);
}

.book-list li:first-child {
  border-top: 1px solid var(--border-color);
}

.book-title {
  display: block;
  font-family: var(--font-sans);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.book-status {
  display: block;
  font-family: var(--font-serif);
  font-size: 0.85rem;
  font-style: italic;
  color: var(--muted-color);
}

/* Newsletter Section */
.newsletter {
  padding: 3rem 0;
  border-top: 1px solid var(--border-color);
  margin-top: 4rem;
}

.newsletter h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
  font-family: var(--font-sans);
}

.signup-form {
  display: flex;
  gap: 0.75rem;
  max-width: 450px;
}

.signup-form input[type="email"] {
  flex-grow: 1;
  background-color: transparent;
  border: 1px solid var(--border-color);
  padding: 0.75rem 1rem;
  font-family: var(--font-serif);
  font-size: 1rem;
  color: var(--text-color);
  outline: none;
  transition: border-color 0.15s ease;
}

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

.signup-form button {
  background-color: var(--text-color);
  color: var(--bg-color);
  border: 1px solid var(--text-color);
  padding: 0.75rem 1.5rem;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.signup-form button:hover {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
}

/* About Page Photo Placeholder & Bio */
.photo-placeholder {
  width: 200px;
  height: 200px;
  border: 1px dashed var(--border-color);
  margin: 0 auto 3rem auto;
  background-color: rgba(0, 0, 0, 0.01);
  border-radius: 4px;
}

.bio-block {
  margin-bottom: 3rem;
}

.bio-block p {
  min-height: 1.5rem;
  margin-bottom: 1.5rem;
}

.contact-info {
  margin-top: 2rem;
  font-size: 1.05rem;
}

/* Footer Section */
footer {
  max-width: var(--max-width);
  width: 100%;
  margin: 5rem auto 0 auto;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
}

.footer-links a {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-decoration: none;
  color: var(--muted-color);
  font-weight: 500;
}

.footer-links a:hover {
  color: var(--text-color);
}

.copyright {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  color: var(--muted-color);
}

/* Mobile Responsiveness */
@media (max-width: 600px) {
  body {
    padding: 2.5rem 1rem;
  }
  
  .author-name {
    font-size: 2.25rem;
  }
  
  .tagline {
    font-size: 1.1rem;
  }
  
  .series-links {
    flex-direction: column;
    gap: 0.75rem;
  }
  
  .divider {
    display: none;
  }
  
  .signup-form {
    flex-direction: column;
  }
  
  .signup-form button {
    width: 100%;
  }
  
  footer {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 1rem;
  }
  
  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
}