/* =============================================================
 * The Technological Republic — Affiliate Landing Page
 * Stylesheet — production build
 *
 * Tone: austere / intellectual / tense
 * Reference: Foreign Affairs + FT Weekend + みすず書房 × Palantir corporate
 *
 * Fonts (load once in <head>):
 *   <link rel="preconnect" href="https://fonts.googleapis.com">
 *   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
 *   <link href="https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,500;0,600;1,500&family=Inter:wght@400;500;600&family=Noto+Sans+JP:wght@400;500&family=Noto+Serif+JP:wght@500;600&display=swap" rel="stylesheet">
 * ============================================================= */

/* -------------------------------------------------------------
 * 1. Design tokens
 * ------------------------------------------------------------- */
:root {
  /* Color — light mode (baseline) */
  --color-ink:           #141618;
  --color-ink-muted:     #3A3F44;
  --color-accent:        #8B1A1A;
  --color-accent-hover:  #6E1414;
  --color-paper:         #F4EFE6;
  --color-paper-raised:  #FBF7EF;
  --color-muted:         #7A7772;
  --color-border:        #D8D0C1;
  --color-rule-strong:   #141618;
  --color-on-accent:     #FFFFFF;

  /* Typography */
  --font-serif: 'Cormorant Garamond', 'Noto Serif JP', 'Times New Roman', 'YuMincho', 'Hiragino Mincho ProN', serif;
  --font-sans:  'Inter', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Hiragino Kaku Gothic ProN', 'Yu Gothic UI', sans-serif;

  --fs-display:  clamp(2.4rem, 5.2vw + 0.6rem, 4.2rem);
  --fs-h2:       clamp(1.75rem, 2.4vw + 0.9rem, 2.5rem);
  --fs-h3:       clamp(1.2rem, 0.8vw + 1rem, 1.4rem);
  --fs-eyebrow:  0.78rem;
  --fs-lead:     clamp(1.05rem, 0.4vw + 1rem, 1.2rem);
  --fs-body:     1rem;
  --fs-small:    0.82rem;
  --fs-quote:    clamp(1.3rem, 1.2vw + 1rem, 1.8rem);

  --lh-tight:    1.22;
  --lh-snug:     1.45;
  --lh-normal:   1.6;
  --lh-reading:  1.85;

  /* Spacing — 8pt scale */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --space-9: 96px;
  --space-10: 128px;

  /* Layout */
  --container-max:     1120px;
  --container-narrow:  720px;
  --gutter:            clamp(20px, 5vw, 48px);

  /* Breakpoints (used in media queries below; documented here) */
  --bp-sm: 640px;
  --bp-md: 1024px;
  --bp-lg: 1280px;

  /* Motion */
  --ease-editorial: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur-fast:   150ms;
  --dur-mid:    180ms;
  --dur-slow:   500ms;
}

/* Dark mode — OS-follow only */
@media (prefers-color-scheme: dark) {
  :root {
    --color-ink:          #ECE6D8;
    --color-ink-muted:    #B8B2A5;
    --color-accent:       #B8342E;
    --color-accent-hover: #D3463F;
    --color-paper:        #14171A;
    --color-paper-raised: #1C2024;
    --color-muted:        #8A867E;
    --color-border:       #2C3036;
    --color-rule-strong:  #ECE6D8;
    --color-on-accent:    #FFFFFF;
  }
}

/* -------------------------------------------------------------
 * 2. Reset / base
 * ------------------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--color-paper);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-reading);
  font-feature-settings: "palt", "kern";
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, picture, svg { max-width: 100%; display: block; }
figure { margin: 0; }

ul, ol { padding-left: 0; list-style: none; margin: 0; }
p { margin: 0 0 1em; }

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--dur-mid) var(--ease-editorial);
}
a:hover { color: var(--color-accent); }

hr {
  border: 0;
  border-top: 1px solid var(--color-border);
  margin: var(--space-8) 0;
}

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

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* -------------------------------------------------------------
 * 3. Typography rules
 * ------------------------------------------------------------- */
h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 600;
  color: var(--color-ink);
  line-height: var(--lh-tight);
  margin: 0 0 var(--space-5);
  font-feature-settings: "liga", "kern", "palt";
  letter-spacing: -0.005em;
}

h1 { font-size: var(--fs-display); line-height: 1.18; letter-spacing: -0.01em; }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); font-weight: 500; }

.eyebrow {
  font-family: var(--font-sans);
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  margin: 0 0 var(--space-4);
}
.eyebrow::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  background: var(--color-accent);
}

.lead {
  font-size: var(--fs-lead);
  line-height: var(--lh-reading);
  color: var(--color-ink);
  max-width: 68ch;
  letter-spacing: 0.01em;
}

.prose {
  max-width: 68ch;
  line-height: var(--lh-reading);
}
.prose p + p { margin-top: 1em; }
.prose strong { font-weight: 600; color: var(--color-ink); }

.muted { color: var(--color-muted); }
.small { font-size: var(--fs-small); }

/* English inline spans inside Japanese copy */
[lang="en"] {
  font-family: var(--font-sans);
  letter-spacing: 0;
}
h1 [lang="en"], h2 [lang="en"], h3 [lang="en"] {
  font-family: var(--font-serif);
  font-style: italic;
}

/* -------------------------------------------------------------
 * 4. Layout utilities
 * ------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container--narrow {
  max-width: var(--container-narrow);
}

section {
  padding-block: var(--space-8);
}

@media (min-width: 1024px) {
  section { padding-block: var(--space-10); }
}

.section-head {
  margin-bottom: var(--space-7);
}

.grid-cards {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

@media (min-width: 1024px) {
  .grid-cards { grid-template-columns: repeat(3, 1fr); }
  /* last two cards span the bottom row */
  .grid-cards > .card:nth-child(4) { grid-column: 1 / span 1; }
  .grid-cards > .card:nth-child(5) { grid-column: 2 / span 1; }
}

.two-col {
  display: grid;
  gap: var(--space-6);
  grid-template-columns: 1fr;
}
@media (min-width: 1024px) {
  .two-col { grid-template-columns: 1fr 2fr; gap: var(--space-8); }
}

.three-col {
  display: grid;
  gap: var(--space-6);
  grid-template-columns: 1fr;
}
@media (min-width: 1024px) {
  .three-col { grid-template-columns: repeat(3, 1fr); }
}

/* -------------------------------------------------------------
 * 5. Navigation
 * ------------------------------------------------------------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 40;
  background: color-mix(in srgb, var(--color-paper) 85%, transparent);
  border-bottom: 1px solid transparent;
  transition: backdrop-filter var(--dur-mid) var(--ease-editorial),
              border-color var(--dur-mid) var(--ease-editorial),
              background var(--dur-mid) var(--ease-editorial);
}
.site-nav.is-scrolled {
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom-color: var(--color-border);
  background: color-mix(in srgb, var(--color-paper) 92%, transparent);
}
.site-nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 56px;
  padding-block: var(--space-3);
}
.site-nav__brand {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.05rem;
  letter-spacing: 0.005em;
}
.site-nav__links {
  display: none;
  align-items: center;
  gap: var(--space-6);
}
.site-nav__links a {
  font-size: 0.9rem;
  color: var(--color-ink-muted);
  position: relative;
  padding-block: 4px;
}
.site-nav__links a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-fast) var(--ease-editorial);
}
.site-nav__links a:hover::after,
.site-nav__links a:focus-visible::after { transform: scaleX(1); }

.site-nav__back {
  color: var(--color-accent) !important;
  font-weight: 600;
  padding-inline: 0.4rem !important;
  margin-right: var(--space-2);
  border-right: 1px solid var(--color-border);
  padding-right: var(--space-4) !important;
}
.site-nav__back:hover { color: var(--color-accent-hover) !important; }

.site-nav__cta {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-ink);
  border-bottom: 1px solid var(--color-ink);
  padding-bottom: 2px;
}
.site-nav__cta:hover { color: var(--color-accent); border-bottom-color: var(--color-accent); }

@media (min-width: 1024px) {
  .site-nav__links { display: flex; }
}

/* -------------------------------------------------------------
 * 6. Hero
 * ------------------------------------------------------------- */
.hero {
  position: relative;
  padding-block: var(--space-9) var(--space-8);
  border-bottom: 1px solid var(--color-border);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 60vh;
  pointer-events: none;
  background: radial-gradient(ellipse at 50% 0%,
                rgba(20,22,24,0.06),
                transparent 60%);
}
@media (prefers-color-scheme: dark) {
  .hero::before {
    background: radial-gradient(ellipse at 50% 0%,
                  rgba(236,230,216,0.05),
                  transparent 60%);
  }
}
.hero__inner { position: relative; }
.hero h1 {
  margin-bottom: var(--space-5);
  max-width: 22ch;
}
.hero__sub {
  font-size: var(--fs-lead);
  font-weight: 500;
  color: var(--color-ink-muted);
  max-width: 46ch;
  margin-bottom: var(--space-5);
  line-height: 1.5;
}
.hero__lead {
  font-size: 1.02rem;
  color: var(--color-ink);
  max-width: 60ch;
  line-height: var(--lh-reading);
  margin-bottom: var(--space-7);
}
.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  align-items: center;
  margin-bottom: var(--space-3);
}
.hero__microcopy {
  font-size: var(--fs-small);
  color: var(--color-muted);
  letter-spacing: 0.02em;
}

@media (min-width: 1024px) {
  .hero { padding-block: var(--space-10) var(--space-9); }
  .hero h1 { max-width: 18ch; }
}

/* Hero with book cover */
.hero__inner--with-cover {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-7, 2rem);
  align-items: start;
}
.hero__figure {
  margin: 0;
  display: flex;
  justify-content: center;
}
.hero__cover {
  width: 100%;
  max-width: 240px;
  height: auto;
  display: block;
  border-radius: 2px;
  box-shadow:
    0 1px 2px rgba(20, 22, 24, 0.08),
    0 12px 32px rgba(20, 22, 24, 0.18);
  background: var(--color-paper-raised);
  transition: transform var(--dur-mid, 0.25s) var(--ease-editorial, ease);
}
.hero__cover:hover { transform: translateY(-2px); }

@media (prefers-color-scheme: dark) {
  .hero__cover {
    box-shadow:
      0 1px 2px rgba(0, 0, 0, 0.5),
      0 12px 32px rgba(0, 0, 0, 0.6);
  }
}

@media (min-width: 900px) {
  .hero__inner--with-cover {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: var(--space-8, 3rem);
    align-items: center;
  }
  .hero__figure {
    justify-content: flex-end;
  }
  .hero__cover {
    max-width: 260px;
  }
}

/* -------------------------------------------------------------
 * 7. Buttons
 * ------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: 44px;
  padding: 14px 28px;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  border-radius: 2px;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--dur-mid) var(--ease-editorial),
              color var(--dur-mid) var(--ease-editorial),
              border-color var(--dur-mid) var(--ease-editorial),
              transform var(--dur-fast) var(--ease-editorial);
}
.btn:hover { color: inherit; }
.btn:active { transform: translateY(1px); }

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

.btn--secondary {
  background: transparent;
  color: var(--color-ink);
  border-color: var(--color-ink);
}
.btn--secondary:hover {
  background: var(--color-ink);
  color: var(--color-paper);
}

.btn--on-dark {
  color: var(--color-paper);
  border-color: var(--color-paper);
}
.btn--on-dark:hover {
  background: var(--color-paper);
  color: var(--color-ink);
}

@media (max-width: 639px) {
  .btn { width: 100%; }
}

/* -------------------------------------------------------------
 * 8. Cards (5 core points)
 * ------------------------------------------------------------- */
.card {
  background: var(--color-paper-raised);
  border: 1px solid var(--color-border);
  border-radius: 3px;
  padding: var(--space-6);
  transition: border-color var(--dur-mid) var(--ease-editorial),
              transform var(--dur-mid) var(--ease-editorial);
}
.card:hover {
  border-color: var(--color-ink);
  transform: translateY(-2px);
}
.card__num {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: var(--fs-eyebrow);
  color: var(--color-accent);
  letter-spacing: 0.12em;
  margin-bottom: var(--space-3);
  display: block;
}
.card h3 {
  margin-bottom: var(--space-3);
}
.card p {
  color: var(--color-ink-muted);
  line-height: var(--lh-reading);
  margin: 0;
}

/* -------------------------------------------------------------
 * 9. Pull quote / highlight
 * ------------------------------------------------------------- */
.pullquote {
  position: relative;
  margin: var(--space-7) 0;
  padding: var(--space-4) var(--space-6) var(--space-4) var(--space-7);
  border-left: 4px solid var(--color-rule-strong);
  font-family: var(--font-serif);
  font-size: var(--fs-quote);
  line-height: 1.55;
  color: var(--color-ink);
  font-weight: 500;
  max-width: 60ch;
}
.pullquote::before {
  content: "\201C";
  position: absolute;
  top: -0.3em;
  left: var(--space-5);
  font-size: 3em;
  color: var(--color-accent);
  opacity: 0.45;
  font-family: var(--font-serif);
  line-height: 1;
  pointer-events: none;
}
.pullquote[lang="ja"]::before,
.pullquote:lang(ja)::before {
  content: "\300C";
}

/* -------------------------------------------------------------
 * 10. Checklist (読むべき読者)
 * ------------------------------------------------------------- */
.checklist {
  max-width: 68ch;
}
.checklist li {
  position: relative;
  padding-left: var(--space-5);
  margin-bottom: var(--space-4);
  line-height: 1.9;
}
.checklist li::before {
  content: "—";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--color-accent);
  font-weight: 600;
}

/* -------------------------------------------------------------
 * 11. FAQ (open list, no accordion)
 * ------------------------------------------------------------- */
.faq {
  max-width: var(--container-narrow);
}
.faq__item {
  padding-block: var(--space-6);
  border-bottom: 1px solid var(--color-border);
}
.faq__item:first-child { border-top: 1px solid var(--color-border); }
.faq__q {
  font-family: var(--font-serif);
  font-size: var(--fs-h3);
  font-weight: 500;
  color: var(--color-ink);
  margin: 0 0 var(--space-3);
}
.faq__a {
  color: var(--color-ink-muted);
  border-left: 2px solid var(--color-border);
  padding-left: var(--space-4);
  margin: 0;
  line-height: var(--lh-reading);
}

/* -------------------------------------------------------------
 * 12. Reviews section
 * ------------------------------------------------------------- */
.review {
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-5);
}
.review__label {
  font-family: var(--font-sans);
  font-size: var(--fs-eyebrow);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin: 0 0 var(--space-4);
  font-weight: 500;
}
.review p {
  color: var(--color-ink);
  line-height: var(--lh-reading);
  font-size: 0.96rem;
  margin: 0;
}
.review-note {
  margin-top: var(--space-6);
  color: var(--color-muted);
  font-size: var(--fs-small);
  max-width: var(--container-narrow);
}

/* -------------------------------------------------------------
 * 13. Author block
 * ------------------------------------------------------------- */
.author__meta {
  color: var(--color-muted);
  font-size: var(--fs-small);
  letter-spacing: 0.04em;
  line-height: 1.6;
}
.author__meta strong {
  display: block;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0;
  color: var(--color-ink);
  margin-bottom: var(--space-2);
}
.author__body p + p { margin-top: 1em; }

.author__list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3, 0.75rem);
}
.author__item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.9rem;
  color: var(--color-ink);
  letter-spacing: 0;
}
.author__avatar {
  width: 48px;
  height: 48px;
  max-width: 48px;
  max-height: 48px;
  flex: 0 0 48px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--color-paper-raised);
  border: 1px solid var(--color-border);
  display: block;
}

/* -------------------------------------------------------------
 * 14. Final CTA section (inverted)
 * ------------------------------------------------------------- */
.cta-final {
  background: var(--color-ink);
  color: var(--color-paper);
  padding-block: var(--space-10);
  margin-top: var(--space-8);
}
.cta-final h2 { color: var(--color-paper); }
.cta-final .lead { color: var(--color-paper); opacity: 0.9; }
.cta-final .hero__microcopy { color: var(--color-paper); opacity: 0.65; }

/* -------------------------------------------------------------
 * 15. Footer
 * ------------------------------------------------------------- */
.site-footer {
  background: var(--color-paper);
  color: var(--color-muted);
  font-size: var(--fs-small);
  padding-block: var(--space-7);
  border-top: 1px solid var(--color-border);
}
.site-footer p { margin: 0 0 var(--space-3); }
.site-footer p:last-child { margin: 0; }
.site-footer a { color: var(--color-ink-muted); border-bottom: 1px dotted currentColor; }
.site-footer a:hover { color: var(--color-accent); border-bottom-color: var(--color-accent); }

/* -------------------------------------------------------------
 * 16. Reveal-on-scroll
 * ------------------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity var(--dur-slow) var(--ease-editorial),
              transform var(--dur-slow) var(--ease-editorial);
  will-change: opacity, transform;
}
.reveal.is-revealed {
  opacity: 1;
  transform: translateY(0);
}

/* -------------------------------------------------------------
 * 17. Utility
 * ------------------------------------------------------------- */
.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}

.stack > * + * { margin-top: var(--space-4); }
.stack-lg > * + * { margin-top: var(--space-6); }

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

/* -------------------------------------------------------------
 * 18. Reduced motion
 * ------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1; transform: none; }
}

/* -------------------------------------------------------------
 * 19. Print (minimal)
 * ------------------------------------------------------------- */
@media print {
  .site-nav, .cta-final, .btn { display: none; }
  body { background: #fff; color: #000; }
}
