:root {
  --ink: #16141a;
  --muted: #635e6b;
  --line: #e4e2dd;
  --paper: #ffffff;
  --soft: #fbfaf7;
  --soft-2: #f4f3f1;
  --accent: #d6230f;
  --header-bg: rgba(255, 255, 255, 0.88);
  color-scheme: light dark;
}

/* Dark mode — mirrors the LP top page's "Ink & Shu (dark)" palette. */
@media (prefers-color-scheme: dark) {
  :root {
    --ink: #f4f1ea;
    --muted: #8a8479;
    --line: #2b2932;
    --paper: #14131a;
    --soft: #1a1922;
    --soft-2: #1d1c24;
    --accent: #ff6b4a;
    --header-bg: rgba(20, 19, 26, 0.88);
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

a {
  color: inherit;
}

/* Header — mirrors the LP top page's SiteHeader. */
.header {
  position: sticky;
  top: 0;
  z-index: 30;
  border-bottom: 1px solid var(--line);
  background: var(--header-bg);
  backdrop-filter: blur(12px);
}

.header-inner {
  max-width: 1240px;
  margin: 0 auto;
  padding: 18px 32px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: clamp(88px, 7vw, 128px);
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 19px;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
}

.wordmark-logo {
  color: var(--ink);
  flex-shrink: 0;
}

.nav {
  display: flex;
  gap: 22px;
  color: var(--muted);
  font-size: 14px;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms ease;
}

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

.header-right {
  display: inline-flex;
  align-items: center;
  gap: 22px;
  margin-left: auto;
}

.lang-switcher {
  list-style: none;
  padding: 0;
  margin: 0;
  display: none;
  align-items: center;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.lang-item {
  display: inline-flex;
  align-items: center;
}

.lang-divider {
  margin: 0 8px;
  color: var(--line);
  user-select: none;
}

.lang-link {
  color: var(--muted);
  text-decoration: none;
  padding: 2px 0;
  transition: color 160ms ease;
}

.lang-link:hover {
  color: var(--ink);
}

.lang-link-active {
  color: var(--accent);
  font-weight: 600;
  cursor: default;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  background: var(--ink);
  color: var(--paper);
  font-size: 13.5px;
  font-weight: 500;
  text-decoration: none;
  border-radius: 999px;
  white-space: nowrap;
  transition: background 160ms ease, transform 160ms ease;
}

.header-cta:hover {
  background: var(--accent);
  transform: translateY(-1px);
}

@media (min-width: 640px) {
  .lang-switcher {
    display: inline-flex;
  }
}

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 72px clamp(20px, 5vw, 56px) 96px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

/* Article (prose) */
.prose h1 {
  margin-bottom: 24px;
  font-size: clamp(32px, 5vw, 50px);
  line-height: 1.08;
  letter-spacing: 0;
}

.prose h2 {
  margin: 48px 0 16px;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.15;
}

.prose p {
  margin: 0 0 20px;
  font-size: 18px;
}

.prose blockquote {
  margin: 24px 0;
  padding: 4px 0 4px 22px;
  border-left: 3px solid var(--accent);
  color: var(--ink);
  font-size: 19px;
}

.prose blockquote p {
  margin: 0 0 10px;
}

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

.prose hr {
  margin: 44px 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.prose em {
  color: var(--muted);
}

.prose figure {
  margin: 32px 0;
}

.prose figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
}

.prose figcaption {
  margin-top: 10px;
  color: var(--muted);
  font-size: 13.5px;
}

/* Placeholder for media to be added later */
.media-placeholder {
  margin: 32px 0;
  padding: 28px;
  border: 1px dashed var(--line);
  border-radius: 10px;
  background: var(--soft);
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

/* Inline download CTA */
/* Matches the LP top page's primary CTA (pill, arrow, lift on hover). */
.cta {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  white-space: nowrap;
  margin: 8px 0 24px;
  padding: 16px 28px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-weight: 500;
  font-size: 15px;
  letter-spacing: -0.005em;
  text-decoration: none;
  transition: transform 200ms ease, background 200ms ease;
}

.cta:hover {
  transform: translateY(-2px);
  background: var(--accent);
}

.cta svg {
  width: 14px;
  height: 14px;
}

/* Index list */
.index-head {
  margin-bottom: 40px;
}

.index-head h1 {
  font-size: clamp(36px, 6vw, 60px);
  line-height: 1.0;
  margin-bottom: 14px;
}

.index-head .lead {
  max-width: 640px;
  color: var(--muted);
  font-size: clamp(17px, 2.2vw, 20px);
}

.article-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.article-list li {
  border-top: 1px solid var(--line);
}

.article-list a {
  display: block;
  padding: 28px 0;
  text-decoration: none;
}

.article-list h2 {
  margin: 0 0 8px;
  font-size: clamp(22px, 3vw, 28px);
  line-height: 1.2;
}

.article-list p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.back-link {
  display: inline-block;
  margin-bottom: 28px;
  color: var(--muted);
  font-size: 14px;
  text-decoration: none;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 56px clamp(20px, 5vw, 56px) 28px;
  color: var(--muted);
  font-size: 14px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  max-width: 1160px;
  margin: 0 auto;
}

.footer-brand {
  margin: 0 0 10px;
  font-size: 22px;
  font-weight: 600;
  color: var(--ink);
}

.footer-tag {
  margin: 0;
  max-width: 360px;
  line-height: 1.6;
}

.footer-col h4 {
  margin: 0 0 14px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

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

.footer-col li {
  margin-bottom: 10px;
}

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

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

.footer-meta {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  max-width: 1160px;
  margin: 48px auto 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.footer-meta a {
  color: var(--ink);
  font-weight: 650;
  text-decoration: none;
}

@media (max-width: 720px) {
  .header-inner {
    gap: 24px;
    flex-wrap: wrap;
  }

  .nav {
    flex-wrap: wrap;
    gap: 16px;
  }

  main {
    padding-top: 48px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 28px;
  }
}