/* ==========================================================================
   Building the Web - Refined Technical Editorial
   ========================================================================== */

/* ---------- Reset ---------- */

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

/* ---------- Design Tokens ---------- */

:root {
  /* Warm paper palette */
  --bg: #f4f1eb;
  --bg-warm: #eae6de;
  --surface: #fffdf8;
  --text: #2a2520;
  --text-secondary: #5c554d;
  --text-muted: #9a9189;
  --accent: #b5451b;
  --accent-hover: #943a16;
  --accent-light: rgba(181, 69, 27, 0.08);
  --border: #d9d4cb;
  --border-light: #e8e4dc;
  --code-bg: #ede9e1;
  --hero-bg: #1b1b26;
  --hero-text: #ede9e1;
  --footer-bg: #23222e;

  /* Typography - Source family: designed for readability across screens */
  --font-display: 'Source Serif 4', Georgia, serif;
  --font-body: 'Source Serif 4', Georgia, 'Times New Roman', serif;
  --font-sans: 'Source Sans 3', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'Source Code Pro', 'Menlo', monospace;

  /* Layout - generous widths */
  --w-prose: 52rem;       /* ~832px - wide enough for comfortable reading */
  --w-content: 64rem;     /* ~1024px - chapter grids, about page */
  --w-wide: 72rem;        /* ~1152px - forms, wide containers */
  --w-full: 80rem;        /* ~1280px - nav, footer */

  /* Spacing scale */
  --s-1: 0.25rem;
  --s-2: 0.5rem;
  --s-3: 0.75rem;
  --s-4: 1rem;
  --s-6: 1.5rem;
  --s-8: 2rem;
  --s-12: 3rem;
  --s-16: 4rem;
  --s-24: 6rem;
  --s-32: 8rem;
}

/* ---------- Base ---------- */

html {
  font-size: 19px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

::selection {
  background: var(--accent-light);
  color: var(--accent);
}

/* ---------- Typography ---------- */

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 400;
  line-height: 1.2;
  color: var(--text);
}

h1 {
  font-size: 2.8rem;
  margin-bottom: var(--s-8);
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.9rem;
  margin-top: var(--s-16);
  margin-bottom: var(--s-6);
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.4rem;
  margin-top: var(--s-12);
  margin-bottom: var(--s-4);
}

h4 {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-top: var(--s-8);
  margin-bottom: var(--s-4);
}

p {
  margin-bottom: var(--s-6);
}

a {
  color: var(--accent);
  text-decoration: none;
  text-underline-offset: 3px;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
  text-decoration-thickness: 1.5px;
}

strong {
  font-weight: 650;
}

blockquote {
  border-left: 3px solid var(--accent);
  padding: var(--s-4) var(--s-8);
  margin: var(--s-8) 0;
  background: var(--accent-light);
  border-radius: 0 6px 6px 0;
  color: var(--text-secondary);
  font-style: italic;
}

blockquote p:last-child {
  margin-bottom: 0;
}

code {
  font-family: var(--font-mono);
  font-size: 0.82em;
  background: var(--code-bg);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  color: var(--accent-hover);
}

pre {
  background: var(--hero-bg);
  color: #c8c3b8;
  padding: var(--s-6) var(--s-8);
  border-radius: 8px;
  overflow-x: auto;
  margin: var(--s-8) 0;
}

pre code {
  background: none;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.7;
  color: inherit;
}

ul, ol {
  margin-bottom: var(--s-6);
  padding-left: var(--s-8);
}

li {
  margin-bottom: var(--s-2);
}

li::marker {
  color: var(--accent);
}

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: var(--s-12) 0;
}

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

/* ---------- Layout ---------- */

.prose-container {
  max-width: var(--w-prose);
  margin: 0 auto;
  padding: var(--s-16) var(--s-8);
}

.content-container {
  max-width: var(--w-content);
  margin: 0 auto;
  padding: var(--s-16) var(--s-8);
}

.content-container--wide {
  max-width: var(--w-wide);
}

/* ---------- Site Header ---------- */

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  background: rgba(255, 253, 248, 0.92);
}

.nav-container {
  max-width: var(--w-full);
  margin: 0 auto;
  padding: 0 var(--s-8);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.site-logo {
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: var(--s-3);
}

.logo-text {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.35rem;
  color: var(--text);
  letter-spacing: -0.01em;
}

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

.site-logo:hover {
  text-decoration: none;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: var(--s-8);
  padding: 0;
  margin: 0;
}

.nav-links a {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  padding: var(--s-2) 0;
  letter-spacing: 0.01em;
  transition: color 0.2s ease;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.25s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
  text-decoration: none;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--s-2);
  flex-direction: column;
  gap: 6px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

/* ---------- Hero ---------- */

.hero {
  background: var(--hero-bg);
  color: var(--hero-text);
  text-align: center;
  padding: var(--s-32) var(--s-8);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% 120%, rgba(181, 69, 27, 0.12), transparent),
    radial-gradient(ellipse 60% 40% at 20% 0%, rgba(100, 100, 160, 0.08), transparent);
  pointer-events: none;
}

.hero-container {
  max-width: var(--w-content);
  margin: 0 auto;
  position: relative;
}

.hero-eyebrow {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin-bottom: var(--s-6);
  opacity: 0;
  animation: fadeUp 0.6s ease forwards;
}

.hero-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 4.5rem;
  color: var(--hero-text);
  margin-bottom: var(--s-6);
  letter-spacing: -0.03em;
  line-height: 1.05;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.1s forwards;
}

.hero-tagline {
  font-family: var(--font-body);
  font-size: 1.25rem;
  color: rgba(237, 233, 225, 0.7);
  max-width: 640px;
  margin: 0 auto;
  line-height: 1.7;
  opacity: 0;
  animation: fadeUp 0.6s ease 0.2s forwards;
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- Home Sections ---------- */

.home-intro {
  background: var(--surface);
  border-bottom: 1px solid var(--border-light);
}

.home-intro .content-container {
  max-width: var(--w-prose);
  font-size: 1.1rem;
}

.home-chapters {
  border-bottom: 1px solid var(--border-light);
}

.home-chapters .content-container {
  max-width: var(--w-content);
}

.home-chapters h2 {
  font-size: 2rem;
  margin-top: 0;
}

.chapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--s-6);
  margin-top: var(--s-8);
}

.chapter-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: var(--s-8);
  text-decoration: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

a.chapter-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 20px rgba(42, 37, 32, 0.08);
  transform: translateY(-2px);
  text-decoration: none;
}

.chapter-card--upcoming {
  opacity: 0.55;
  background: transparent;
}

.chapter-card .chapter-number {
  font-family: var(--font-sans);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.chapter-card h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin: var(--s-2) 0 var(--s-3);
  color: var(--text);
  line-height: 1.25;
}

.chapter-card p {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: var(--s-4);
  line-height: 1.55;
  flex: 1;
}

.chapter-status {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.status-published {
  color: var(--accent);
}

.status-upcoming {
  color: var(--text-muted);
}

/* ---------- Chapter Content ---------- */

.chapter-content .content-container {
  max-width: var(--w-prose);
}

.chapter-header {
  margin-bottom: var(--s-12);
  padding-bottom: var(--s-8);
  border-bottom: 1px solid var(--border-light);
}

.chapter-number-label {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  display: block;
  margin-bottom: var(--s-3);
}

.chapter-header h1 {
  font-size: 3rem;
}

.chapter-description {
  font-size: 1.2rem;
  color: var(--text-secondary);
  margin-top: var(--s-4);
  line-height: 1.65;
}

.chapter-body {
  font-size: 1.05rem;
}

.chapter-body h2 {
  margin-top: var(--s-24);
  padding-top: var(--s-8);
  border-top: 1px solid var(--border-light);
}

.chapter-body h2:first-child {
  margin-top: var(--s-8);
  padding-top: 0;
  border-top: none;
}

.chapter-body h3 {
  margin-top: var(--s-12);
}

.chapter-body p + p {
  margin-top: 0;
}

/* ---------- Chapter Navigation ---------- */

.chapter-nav {
  display: flex;
  justify-content: space-between;
  margin-top: var(--s-16);
  padding-top: var(--s-8);
  border-top: 2px solid var(--border);
  font-family: var(--font-sans);
  font-size: 0.9rem;
}

.chapter-nav a {
  font-weight: 500;
}

/* ---------- Share Buttons ---------- */

.share-buttons {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  margin: var(--s-8) 0;
  padding: var(--s-4) 0;
}

.share-label {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-right: var(--s-2);
}

.share-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  position: relative;
}

.share-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
  text-decoration: none;
}

.copy-feedback {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-sans);
  font-size: 0.68rem;
  font-weight: 500;
  background: var(--text);
  color: var(--surface);
  padding: 3px 10px;
  border-radius: 5px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.share-btn.copied .copy-feedback {
  opacity: 1;
}

/* ---------- About Page ---------- */

.about-page .content-container {
  max-width: var(--w-prose);
}

.about-author {
  margin-top: var(--s-16);
  padding-top: var(--s-12);
  border-top: 1px solid var(--border-light);
}

.author-card {
  display: flex;
  gap: var(--s-12);
  align-items: flex-start;
  margin-top: var(--s-8);
}

.author-photo {
  flex-shrink: 0;
  width: 200px;
  height: 200px;
  border-radius: 10px;
  overflow: hidden;
  background: var(--border-light);
  box-shadow: 0 4px 16px rgba(42, 37, 32, 0.1);
}

.author-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.author-bio p {
  font-size: 1rem;
  line-height: 1.75;
}

.author-links {
  display: flex;
  gap: var(--s-6);
  margin-top: var(--s-6);
  font-family: var(--font-sans);
  font-size: 0.85rem;
}

.author-links a {
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
}

/* ---------- Introduction Page ---------- */

.introduction-page .content-container {
  max-width: var(--w-prose);
}

.introduction-page .chapter-body {
  font-size: 1.05rem;
}

/* ---------- Contact / Subscribe Pages ---------- */

.contact-form-embed,
.subscribe-form-embed {
  margin-top: var(--s-8);
}

/* ---------- Page Content ---------- */

.page-content {
  min-height: 50vh;
}

.page-content > .content-container {
  max-width: var(--w-prose);
}

.page-content > .content-container--wide {
  max-width: var(--w-wide);
}

/* ---------- List Items ---------- */

.list-item {
  padding: var(--s-8) 0;
  border-bottom: 1px solid var(--border-light);
}

.list-item:last-child {
  border-bottom: none;
}

.list-item h2 {
  font-size: 1.4rem;
  margin: 0 0 var(--s-2);
}

.list-item p {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin: 0;
}

/* ---------- Footer ---------- */

.site-footer {
  background: var(--footer-bg);
  color: var(--hero-text);
  margin-top: auto;
}

.footer-container {
  max-width: var(--w-full);
  margin: 0 auto;
  padding: var(--s-16) var(--s-8) var(--s-8);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: var(--s-16);
  margin-bottom: var(--s-12);
}

.footer-col h4 {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: rgba(237, 233, 225, 0.4);
  margin-bottom: var(--s-4);
}

.footer-col ul {
  list-style: none;
  padding: 0;
}

.footer-col li {
  margin-bottom: var(--s-3);
}

.footer-col a {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: rgba(237, 233, 225, 0.7);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-col a:hover {
  color: var(--hero-text);
  text-decoration: none;
}

.footer-bottom {
  padding-top: var(--s-8);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
}

.footer-bottom p {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  color: rgba(237, 233, 225, 0.3);
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  html {
    font-size: 17px;
  }

  .hero {
    padding: var(--s-16) var(--s-6);
  }

  .hero-title {
    font-size: 3rem;
  }

  .chapter-grid {
    grid-template-columns: 1fr;
  }

  .content-container,
  .prose-container {
    padding: var(--s-12) var(--s-6);
  }
}

@media (max-width: 768px) {
  html {
    font-size: 16px;
  }

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

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

  h1 {
    font-size: 2.2rem;
  }

  .chapter-header h1 {
    font-size: 2.2rem;
  }

  .content-container,
  .prose-container {
    padding: var(--s-8) var(--s-4);
  }

  /* Mobile nav */
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: var(--s-4) var(--s-8);
    gap: 0;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  }

  .nav-links.nav-open {
    display: flex;
  }

  .nav-links li {
    padding: var(--s-3) 0;
  }

  .nav-links a::after {
    display: none;
  }

  /* Author card */
  .author-card {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .author-links {
    justify-content: center;
    flex-wrap: wrap;
  }

  /* Footer */
  .footer-links {
    flex-direction: column;
    gap: var(--s-8);
  }

  /* Share */
  .share-buttons {
    flex-wrap: wrap;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  h1 {
    font-size: 1.8rem;
  }

  h2 {
    font-size: 1.5rem;
  }
}