:root {
  --color-paper-white: #fdfcfa;
  --color-paper-soft: #f6f1e8;
  --color-ink-black: #0a0a0b;
  --color-ink-gray: #444446;
  --color-ink-soft: #6d6962;
  --color-line: rgba(10, 10, 11, 0.1);
  --color-line-strong: rgba(10, 10, 11, 0.16);
  --color-accent-teal: #2d6a6a;
  --color-accent-bronze: #806b3a;
  --shadow-soft: 0 18px 48px rgba(10, 10, 11, 0.06);
  --font-primary: "Inter", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--color-ink-black);
  background:
    radial-gradient(circle at top left, rgba(45, 106, 106, 0.08), transparent 28%),
    radial-gradient(circle at top right, rgba(128, 107, 58, 0.08), transparent 24%),
    var(--color-paper-white);
  font-family: var(--font-primary);
  font-size: 18px;
  line-height: 1.85;
}

a {
  color: inherit;
}

.container {
  width: min(1440px, calc(100% - 48px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(253, 252, 250, 0.88);
  border-bottom: 1px solid var(--color-line);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 104px;
}

.brand {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.brand__logo {
  display: block;
  width: auto;
  height: 60px;
}

.language-select {
  position: relative;
}

.language-trigger {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-width: 48px;
  min-height: 48px;
  padding: 10px 12px;
  border: 1px solid var(--color-line-strong);
  background: rgba(253, 252, 250, 0.96);
  color: var(--color-ink-black);
  cursor: pointer;
}

.language-trigger img,
.language-option img {
  display: block;
  width: 20px;
  height: 14px;
  object-fit: cover;
  flex: 0 0 auto;
}

.language-icon {
  color: var(--color-ink-soft);
  transition: transform 0.18s ease;
}

.language-trigger[aria-expanded="true"] .language-icon {
  transform: rotate(180deg);
}

.language-dropdown {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 30;
  min-width: 180px;
  padding: 8px;
  border: 1px solid var(--color-line);
  background: rgba(255, 255, 255, 0.98);
  box-shadow: var(--shadow-soft);
}

.language-option {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 10px 12px;
  border: 0;
  background: transparent;
  color: var(--color-ink-black);
  text-align: left;
  cursor: pointer;
  font: inherit;
}

.language-option span {
  display: block;
  line-height: 1.3;
}

.language-option:hover,
.language-option.active {
  background: rgba(45, 106, 106, 0.08);
}

.language-option[disabled] {
  opacity: 0.45;
  cursor: not-allowed;
}

.eyebrow,
.toc-card__title,
.overview-block__title,
.meta-chip label {
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.overview-section {
  padding: 84px 0 40px;
}

.overview-title,
.document-panel__header h2,
.document-article h2,
.document-article h3,
.standalone-article h1,
.standalone-article h2,
.standalone-article h3 {
  margin: 0;
  font-family: var(--font-primary);
  line-height: 1.08;
}

.overview-title {
  margin-top: 8px;
  max-width: 12ch;
  font-size: clamp(3rem, 8vw, 5rem);
}

.overview-date {
  margin: 18px 0 0;
  color: var(--color-ink-gray);
  font-size: 1rem;
}

.overview-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 36px;
}

.overview-block,
.document-panel,
.toc-card {
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--color-line);
  box-shadow: var(--shadow-soft);
}

.overview-block {
  padding: 24px;
}

.overview-block__title {
  margin: 0 0 18px;
  color: var(--color-ink-soft);
}

.overview-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.overview-list li {
  margin: 0;
}

.document-list__item {
  position: relative;
  display: block;
  width: 100%;
  padding: 16px 16px 16px 64px;
  border: 1px solid var(--color-line);
  background: rgba(253, 252, 250, 0.78);
  text-align: left;
  text-decoration: none;
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.document-list__item:hover,
.document-list__item.is-active {
  transform: translateY(-1px);
  border-color: var(--color-line-strong);
  background: rgba(255, 255, 255, 0.92);
}

.document-list__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  bottom: 14px;
  width: 3px;
  background: transparent;
}

.document-list__item.is-active::before {
  background: linear-gradient(180deg, var(--color-accent-teal), var(--color-accent-bronze));
}

.document-list__index {
  position: absolute;
  left: 16px;
  top: 16px;
  min-width: 32px;
  color: var(--color-ink-soft);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.document-list__content {
  display: block;
}

.document-list__content strong {
  display: block;
  margin-bottom: 6px;
  font-size: 0.98rem;
}

.document-list__content small {
  color: var(--color-ink-soft);
}

.detail-section {
  padding: 0 0 64px;
}

.detail-section--page {
  padding-top: 56px;
}

.detail-stack {
  display: grid;
  gap: 0;
}

.back-link {
  display: inline-flex;
  margin-bottom: 16px;
  color: var(--color-ink-gray);
  text-decoration: none;
  font-weight: 500;
}

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

#version-switcher {
  width: 100%;
  min-width: 220px;
  padding: 12px 14px;
  border: 1px solid var(--color-line-strong);
  background: rgba(253, 252, 250, 0.96);
  color: var(--color-ink-black);
  font: inherit;
}

.document-panel {
  padding: 30px;
  overflow: hidden;
}

.document-panel--full {
  width: 100%;
}

.document-panel__header {
  padding-bottom: 26px;
  border-bottom: 1px solid var(--color-line);
}

.document-panel__header h2 {
  margin-top: 8px;
  font-size: clamp(2rem, 4vw, 3.1rem);
  max-width: 18ch;
}

.document-header__meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
  margin-top: 14px;
}

.document-effective-inline {
  margin: 0;
  color: var(--color-ink-gray);
}

.meta-chip {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 14px;
  border: 1px solid var(--color-line);
  background: rgba(253, 252, 250, 0.82);
}

.meta-chip[hidden] {
  display: none;
}

.meta-chip label {
  margin: 0;
  white-space: nowrap;
}

.document-panel__body {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: 28px;
  padding-top: 28px;
  align-items: start;
}

.document-panel__body--single {
  grid-template-columns: 220px minmax(0, 1fr);
}

.document-panel__body--no-toc {
  grid-template-columns: minmax(0, 1fr);
}

.toc-card {
  position: sticky;
  top: 112px;
  padding: 18px;
  height: fit-content;
  max-height: calc(100vh - 136px);
  overflow: auto;
  overscroll-behavior: contain;
}

.toc-card[hidden] {
  display: none;
}

.toc-card__title {
  margin: 0 0 14px;
}

#document-toc {
  display: grid;
  gap: 8px;
}

#document-toc a {
  display: block;
  color: var(--color-ink-gray);
  text-decoration: none;
  font-size: 0.95rem;
  line-height: 1.45;
  word-break: break-word;
}

.document-article,
.standalone-article__content {
  min-width: 0;
}

.document-article a,
.standalone-article__content a {
  overflow-wrap: normal;
  word-break: normal;
}

.document-article p,
.document-article ul,
.document-article ol,
.standalone-article__content p,
.standalone-article__content ul,
.standalone-article__content ol {
  margin: 0 0 18px;
}

.document-article h2,
.standalone-article__content h2 {
  margin: 52px 0 18px;
  font-size: clamp(1.7rem, 2.4vw, 2.2rem);
}

.document-article h3,
.standalone-article__content h3 {
  margin: 28px 0 14px;
  font-size: 1.24rem;
}

.document-article ul,
.standalone-article__content ul {
  padding-left: 0;
  list-style: none;
}

.document-article ol,
.standalone-article__content ol {
  padding-left: 24px;
}

.document-article li,
.standalone-article__content li {
  position: relative;
  padding-left: 20px;
}

.document-article ul li::before,
.standalone-article__content ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--color-accent-bronze);
  transform: translateY(-50%);
}

.document-article code,
.standalone-article__content code {
  padding: 0.1em 0.35em;
  background: rgba(10, 10, 11, 0.06);
  font-size: 0.92em;
}

.document-standalone {
  padding: 48px 24px;
}

.standalone-article {
  width: min(920px, 100%);
  margin: 0 auto;
  padding: 28px 32px 36px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--color-line);
  box-shadow: var(--shadow-soft);
}

.standalone-article__header h1 {
  margin-top: 8px;
  font-size: clamp(2.4rem, 5vw, 3.4rem);
}

.standalone-article__effective {
  margin: 14px 0 0;
  color: var(--color-ink-gray);
}

@media (max-width: 1120px) {
  .overview-columns,
  .document-panel__body {
    grid-template-columns: 1fr;
  }

  .toc-card {
    position: static;
    max-height: none;
    overflow: visible;
  }
}

@media (max-width: 720px) {
  body {
    font-size: 16px;
  }

  .container {
    width: min(100% - 32px, 1440px);
  }

  .site-header__inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 14px;
    min-height: 84px;
    padding: 16px 0;
  }

  .brand__logo {
    height: 48px;
  }

  .language-select {
    width: auto;
    margin-left: auto;
  }

  .language-trigger {
    min-width: 44px;
    min-height: 44px;
    padding: 10px;
    justify-content: center;
  }

  .language-dropdown {
    left: auto;
    right: 0;
    min-width: 152px;
    max-width: min(220px, calc(100vw - 32px));
  }

  .overview-section {
    padding-top: 56px;
  }

  .overview-columns {
    gap: 16px;
    margin-top: 28px;
  }

  .document-panel,
  .standalone-article {
    padding: 20px;
  }

  .detail-section--page {
    padding-top: 28px;
  }

  .document-panel__header h2 {
    max-width: none;
    font-size: clamp(1.7rem, 8vw, 2.35rem);
  }

  .document-panel__body {
    gap: 20px;
    padding-top: 22px;
  }

  .document-header__meta-row,
  .meta-chip {
    align-items: stretch;
  }

  .meta-chip {
    width: 100%;
    flex-direction: column;
  }

  #version-switcher {
    min-width: 0;
  }

  .toc-card {
    padding: 16px;
  }

  .document-article h2,
  .standalone-article__content h2 {
    margin: 38px 0 14px;
    font-size: clamp(1.45rem, 6vw, 1.9rem);
  }

  .document-article h3,
  .standalone-article__content h3 {
    margin: 22px 0 12px;
    font-size: 1.08rem;
  }

  .document-list__item {
    padding: 14px 14px 14px 58px;
  }

  .document-list__index {
    left: 14px;
    top: 14px;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 15px;
    line-height: 1.75;
  }

  .container {
    width: min(100% - 24px, 1440px);
  }

  .brand__logo {
    height: 42px;
  }

  .site-header__inner {
    gap: 12px;
    min-height: 72px;
    padding: 12px 0;
  }

  .overview-title {
    font-size: clamp(2.2rem, 11vw, 3rem);
  }

  .overview-block,
  .document-panel,
  .standalone-article {
    padding: 18px;
  }

  .language-trigger,
  #version-switcher {
    padding: 11px 12px;
  }

  .language-trigger {
    min-width: 40px;
    min-height: 40px;
    padding: 8px;
  }

  .language-dropdown {
    min-width: 144px;
    padding: 6px;
  }

  .language-option {
    gap: 10px;
    padding: 9px 10px;
  }

  .language-option span {
    font-size: 0.95rem;
  }
}