:root {
  --bg: #FFFFFF;
  --ink: #1A1A1A;
  --ink-soft: #6E6B68;
  --ink-faint: #A3A19E;
  --ink-fainter: #B5B3AF;
  --rule: #EFEDE8;
  --accent: #B5483E;
  --font: 'DM Sans', 'Noto Sans JP', 'Noto Sans Arabic', system-ui, -apple-system, sans-serif;
  color-scheme: light;
}

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

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

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding: 3.5rem 1.5rem 8rem;
}

.lang-section {
  display: none;
  animation: fadeIn 0.4s ease-out;
}

html[lang="fr"] .lang-section[data-lang="fr"],
html[lang="en"] .lang-section[data-lang="en"],
html[lang="es"] .lang-section[data-lang="es"],
html[lang="pt"] .lang-section[data-lang="pt"],
html[lang="de"] .lang-section[data-lang="de"],
html[lang="ar"] .lang-section[data-lang="ar"],
html[lang="ja"] .lang-section[data-lang="ja"] {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

a { color: inherit; }

.container { max-width: 640px; margin: 0 auto; }

.site-header {
  max-width: 640px;
  margin: 0 auto 6rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.site-title {
  text-decoration: none;
  color: var(--ink);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: -0.003em;
  transition: color 0.4s ease;
}

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

.lang-switcher {
  display: flex;
  gap: 4px;
  align-items: center;
  flex-wrap: wrap;
}

.lang-flag {
  background: none;
  border: 1px solid transparent;
  padding: 3px 5px;
  cursor: pointer;
  font-size: 15px;
  line-height: 1;
  border-radius: 3px;
  opacity: 0.45;
  filter: saturate(0.6);
  transition: opacity 0.2s ease, filter 0.2s ease, border-color 0.2s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: inherit;
}

.lang-flag:hover {
  opacity: 1;
  filter: saturate(1);
}

html[lang="fr"] .lang-flag[data-lang="fr"],
html[lang="en"] .lang-flag[data-lang="en"],
html[lang="es"] .lang-flag[data-lang="es"],
html[lang="pt"] .lang-flag[data-lang="pt"],
html[lang="de"] .lang-flag[data-lang="de"],
html[lang="ar"] .lang-flag[data-lang="ar"],
html[lang="ja"] .lang-flag[data-lang="ja"] {
  opacity: 1;
  filter: saturate(1);
  border-color: var(--rule);
}

.intro { margin-bottom: 6rem; }

.intro-eyebrow {
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 1.5rem;
  font-weight: 400;
}

.intro h1 {
  font-weight: 400;
  font-size: clamp(34px, 5.5vw, 50px);
  line-height: 1.1;
  letter-spacing: -0.025em;
  margin-bottom: 1.75rem;
  color: var(--ink);
  max-width: 440px;
}

.intro p {
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink-soft);
  max-width: 460px;
}

.section-label {
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 0;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--rule);
  font-weight: 400;
}

.theses-list { list-style: none; }

.thesis-item { border-bottom: 1px solid var(--rule); }

.thesis-link {
  display: grid;
  grid-template-columns: 36px 1fr;
  gap: 24px;
  align-items: baseline;
  padding: 2.25rem 0;
  text-decoration: none;
  color: inherit;
  transition: padding-inline-start 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.thesis-link:hover { padding-inline-start: 10px; }

.thesis-number {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-faint);
  padding-top: 4px;
  font-weight: 500;
}

.thesis-title {
  font-size: clamp(20px, 2.6vw, 22px);
  line-height: 1.3;
  font-weight: 500;
  letter-spacing: -0.012em;
  margin-bottom: 0.4rem;
  transition: color 0.4s ease;
  color: var(--ink);
}

.thesis-link:hover .thesis-title { color: var(--accent); }

.thesis-subtitle {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.5;
  margin-bottom: 0.6rem;
  max-width: 95%;
}

.thesis-date {
  font-size: 10px;
  color: var(--ink-fainter);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-weight: 400;
}

.article-header { margin-bottom: 4rem; }

.article-number {
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--ink-faint);
  margin-bottom: 2rem;
  font-weight: 500;
  text-transform: uppercase;
}

.article-title {
  font-weight: 400;
  font-size: clamp(34px, 5.5vw, 52px);
  line-height: 1.08;
  letter-spacing: -0.025em;
  margin-bottom: 1.25rem;
  color: var(--ink);
}

.article-subtitle {
  font-size: 18px;
  font-weight: 400;
  color: var(--ink-soft);
  line-height: 1.5;
  margin-bottom: 2rem;
  max-width: 95%;
}

.article-meta {
  font-size: 10px;
  color: var(--ink-faint);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  display: flex;
  gap: 1.5rem;
  font-weight: 400;
  flex-wrap: wrap;
}

.article-body { font-size: 17px; line-height: 1.8; color: var(--ink); }

.article-body h2 {
  font-weight: 500;
  font-size: 22px;
  line-height: 1.25;
  letter-spacing: -0.012em;
  color: var(--ink);
  margin: 4rem 0 1.25rem;
}

.article-body p { margin-bottom: 1.25rem; }

.article-body em, .article-body i { font-style: italic; color: var(--ink); }

.article-body strong { font-weight: 500; }

.article-end {
  text-align: center;
  margin: 4rem 0 3.5rem;
  color: var(--ink-faint);
  font-size: 18px;
  letter-spacing: 0.6em;
  padding-inline-start: 0.6em;
}

.article-footer {
  border-top: 1px solid var(--rule);
  padding-top: 2rem;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-size: 13px;
  gap: 1rem;
  flex-wrap: wrap;
}

.article-footer a {
  text-decoration: none;
  color: var(--ink);
  transition: color 0.4s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 400;
}

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

.article-footer .footer-date {
  font-size: 10px;
  color: var(--ink-faint);
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.placeholder {
  padding: 2rem 0;
}

.placeholder p {
  font-size: 17px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 1.5rem;
}

.placeholder-link {
  background: none;
  border: none;
  font-family: inherit;
  font-size: 15px;
  color: var(--ink);
  cursor: pointer;
  padding: 0;
  text-decoration: underline;
  text-decoration-color: var(--ink-faint);
  text-underline-offset: 3px;
  transition: text-decoration-color 0.3s ease;
}

.placeholder-link:hover { text-decoration-color: var(--accent); }

html[dir="rtl"] .thesis-link { grid-template-columns: 1fr 36px; }
html[dir="rtl"] .article-end { padding-inline-start: 0; padding-inline-end: 0.6em; }
html[dir="rtl"] .article-footer a span[aria-hidden="true"] { transform: rotate(180deg); display: inline-block; }

@media (max-width: 560px) {
  body { padding: 2.5rem 1.25rem 6rem; }
  .site-header { margin-bottom: 4rem; }
  .intro { margin-bottom: 4.5rem; }
  .thesis-link { grid-template-columns: 1fr; gap: 0.6rem; padding: 1.75rem 0; }
  .thesis-link:hover { padding-inline-start: 0; }
  .thesis-number { padding-top: 0; }
  .article-body { font-size: 16px; }
  .article-footer { flex-direction: column; gap: 0.75rem; align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  body, .lang-section, .thesis-link, .thesis-title, .site-title, .article-footer a, .lang-flag {
    animation: none !important;
    transition: none !important;
  }
}