:root {
  --background: #080b0e;
  --surface: #0d1116;
  --surface-hover: #11161c;

  --border: #1b232c;

  --text: #f1f4f6;
  --muted: #8b949e;
  --dim: #59636d;

  --accent: #65d68b;

  --max-width: 1180px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background: var(--background);
  color: var(--text);

  font-family:
    Inter,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;

  line-height: 1.6;

  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(calc(100% - 48px), var(--max-width));

  margin: 0 auto;
}

/* ---------------- HEADER ---------------- */

.site-header {
  border-bottom: 1px solid var(--border);

  background: rgba(8, 11, 14, 0.88);

  position: sticky;
  top: 0;
  z-index: 10;

  backdrop-filter: blur(12px);
}

.nav {
  height: 72px;

  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  font-family: monospace;

  font-size: 13px;
  font-weight: 700;

  letter-spacing: 0.12em;

  color: var(--accent);

  border: 1px solid var(--accent);

  padding: 4px 7px;
}

.brand-name {
  font-size: 14px;
  color: var(--muted);
}

nav {
  display: flex;
  gap: 30px;
}

nav a {
  font-size: 14px;
  color: var(--muted);

  transition: color 0.2s ease;
}

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

/* ---------------- PAGE HERO ---------------- */

.page-hero {
  padding: 105px 0 90px;

  border-bottom: 1px solid var(--border);
}

.breadcrumb {
  margin-bottom: 28px;

  font-family: monospace;

  font-size: 11px;

  letter-spacing: 0.08em;

  color: var(--dim);
}

.breadcrumb a {
  color: var(--muted);

  transition: color 0.2s ease;
}

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

.eyebrow {
  font-family: monospace;

  font-size: 11px;

  letter-spacing: 0.18em;

  color: var(--accent);

  margin-bottom: 20px;
}

.page-hero h1 {
  max-width: 800px;

  font-size: clamp(48px, 6vw, 72px);

  line-height: 1.04;

  letter-spacing: -0.045em;

  font-weight: 650;
}

.page-hero > .container > p {
  max-width: 700px;

  margin-top: 28px;

  color: var(--muted);

  font-size: 19px;

  line-height: 1.7;
}

.series-note {
  display: flex;

  align-items: center;

  gap: 16px;

  margin-top: 32px;

  padding-top: 22px;

  border-top: 1px solid var(--border);

  max-width: 700px;

  color: var(--muted);

  font-size: 13px;
}

.note-label {
  font-family: monospace;

  font-size: 9px;

  letter-spacing: 0.14em;

  color: var(--accent);

  white-space: nowrap;
}

/* ---------------- SECTIONS ---------------- */

.section {
  padding: 110px 0;
}

.series-intro {
  border-bottom: 1px solid var(--border);
}

.intro-grid {
  display: grid;

  grid-template-columns: 1fr 1fr;

  gap: 100px;
}

.intro-grid h2 {
  max-width: 580px;

  font-size: clamp(32px, 4vw, 50px);

  line-height: 1.08;

  letter-spacing: -0.035em;
}

.intro-text {
  max-width: 540px;

  color: var(--muted);

  font-size: 17px;
}

.intro-text p + p {
  margin-top: 24px;
}

/* ---------------- SECTION HEADING ---------------- */

.section-heading {
  max-width: 700px;

  margin-bottom: 55px;
}

.section-heading h2 {
  font-size: clamp(32px, 4vw, 48px);

  line-height: 1.1;

  letter-spacing: -0.03em;
}

.section-heading p {
  margin-top: 18px;

  color: var(--muted);

  font-size: 16px;
}

/* ---------------- CHAPTERS ---------------- */

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

.chapters-list {
  display: flex;

  flex-direction: column;

  gap: 12px;
}

.chapter-card {
  display: grid;

  grid-template-columns: 90px minmax(0, 1fr) auto;

  align-items: center;

  gap: 30px;

  min-height: 145px;

  padding: 28px 30px;

  border: 1px solid var(--border);

  background: var(--surface);

  transition:
    background 0.2s ease,
    border-color 0.2s ease;
}

.chapter-card:hover {
  background: var(--surface-hover);

  border-color: #2b3742;
}

.chapter-number {
  font-family: monospace;

  font-size: 34px;

  color: var(--dim);
}

.chapter-content {
  min-width: 0;
}

.card-meta {
  font-family: monospace;

  font-size: 9px;

  letter-spacing: 0.12em;

  color: var(--accent);

  margin-bottom: 9px;
}

.chapter-content h3 {
  font-size: 24px;

  line-height: 1.2;

  letter-spacing: -0.02em;
}

.chapter-content p {
  max-width: 680px;

  margin-top: 9px;

  color: var(--muted);

  font-size: 14px;
}

.chapter-status {
  font-family: monospace;

  font-size: 9px;

  letter-spacing: 0.14em;

  color: var(--dim);

  white-space: nowrap;
}

.chapter-link {
  font-family: monospace;

  font-size: 10px;

  font-weight: 600;

  letter-spacing: 0.14em;

  color: var(--accent);

  white-space: nowrap;
}

/* ---------------- DISCLAIMER ---------------- */

.disclaimer-section {
  padding: 60px 0;
}

.security-warning {
  padding: 16px 18px;

  border-left: 2px solid var(--accent);

  background: rgba(101, 214, 139, 0.035);

  font-family: monospace;
}

.warning-title {
  font-size: 10px;

  letter-spacing: 0.14em;

  color: var(--accent);

  margin-bottom: 8px;
}

.security-warning p {
  margin: 0;

  max-width: 760px;

  font-family:
    Inter,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;

  font-size: 12px;

  line-height: 1.6;

  color: var(--muted);
}

/* ---------------- FOOTER ---------------- */

.site-footer {
  padding: 42px 0;
}

.footer-content {
  display: flex;

  justify-content: space-between;

  align-items: center;

  gap: 30px;
}

.footer-brand {
  display: flex;

  flex-direction: column;

  gap: 4px;
}

.footer-content strong {
  font-size: 13px;
}

.footer-content span {
  font-size: 12px;

  color: var(--dim);
}

.footer-address {
  margin-top: 10px;

  line-height: 1.6;
}

.footer-links {
  display: flex;

  flex-direction: column;

  align-items: flex-end;

  gap: 12px;
}

.footer-main-links,
.footer-legal-links {
  display: flex;

  flex-wrap: wrap;

  justify-content: flex-end;

  gap: 8px 24px;
}

.footer-links a {
  font-size: 12px;

  color: var(--muted);

  transition: color 0.2s ease;
}

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

/* ---------------- MOBILE ---------------- */

@media (max-width: 850px) {
  .brand-name {
    display: none;
  }

  .nav {
    height: 64px;
  }

  nav {
    gap: 18px;
  }

  .page-hero {
    padding: 75px 0 70px;
  }

  .intro-grid {
    grid-template-columns: 1fr;

    gap: 45px;
  }

  .chapter-card {
    grid-template-columns: 60px minmax(0, 1fr);

    gap: 20px;

    padding: 25px 22px;
  }

  .chapter-status,
  .chapter-link {
    grid-column: 2;
  }

  .footer-content {
    flex-direction: column;

    align-items: flex-start;
  }

  .footer-links {
    align-items: flex-start;
  }

  .footer-main-links,
  .footer-legal-links {
    justify-content: flex-start;
  }
}

@media (max-width: 500px) {
  .container {
    width: min(calc(100% - 32px), var(--max-width));
  }

  .page-hero h1 {
    font-size: 45px;
  }

  .page-hero > .container > p {
    font-size: 17px;
  }

  .series-note {
    align-items: flex-start;

    flex-direction: column;

    gap: 8px;
  }

  .section {
    padding: 80px 0;
  }

  .chapter-card {
    grid-template-columns: 48px minmax(0, 1fr);

    gap: 16px;

    padding: 22px 18px;
  }

  .chapter-number {
    font-size: 28px;
  }

  .chapter-content h3 {
    font-size: 21px;
  }

  .chapter-status,
  .chapter-link {
    grid-column: 2;
  }
}