/* Multilinguistics v01: serif reading, sans-serif controls and two blue editorial palettes. */

:root {
  color-scheme: light;
  --bg: #ffffff;
  --surface: #f8f9fa;
  --surface-alt: #e8eff8;
  --text: #2b2d42;
  --muted: #495057;
  --line: #c5d3e4;
  --control-border: #647b96;
  --primary: #0d47a1;
  --accent: #005bc8;
  --on-primary: #ffffff;
  --draft-bg: #fff4d6;
  --draft-text: #5a4300;
  --font-serif: "AK Serif", "CMU Serif", "Latin Modern Roman", Georgia, serif;
  --font-sans: "AK Sans", "CMU Sans Serif", "Latin Modern Sans", system-ui, sans-serif;
  --space: 1rem;
}

:root[data-palette="dark"] {
  color-scheme: dark;
  --bg: #0b1628;
  --surface: #12223a;
  --surface-alt: #1a3050;
  --text: #e9eef6;
  --muted: #b4c2d6;
  --line: #2a3f5e;
  --control-border: #7894b8;
  --primary: #83c4f8;
  --accent: #9ccffa;
  --on-primary: #0b1628;
  --draft-bg: #3a3011;
  --draft-text: #f6e2a8;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-palette="light"]) {
    color-scheme: dark;
    --bg: #0b1628;
    --surface: #12223a;
    --surface-alt: #1a3050;
    --text: #e9eef6;
    --muted: #b4c2d6;
    --line: #2a3f5e;
    --control-border: #7894b8;
    --primary: #83c4f8;
    --accent: #9ccffa;
    --on-primary: #0b1628;
    --draft-bg: #3a3011;
    --draft-text: #f6e2a8;
  }
}

*, *::before, *::after { box-sizing: border-box; }
/* Author display rules must not reveal controls that require JavaScript. */
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; padding-bottom: 6rem; background: var(--bg); color: var(--text); font-family: var(--font-serif); font-size: 1.125rem; line-height: 1.68; overflow-wrap: anywhere; }
img, svg { max-width: 100%; }

.wrap { max-width: 72rem; margin-inline: auto; padding-inline: clamp(1rem, 4vw, 2rem); }
.reading { max-width: 46rem; padding-block: clamp(2rem, 6vw, 3rem) calc(var(--space) * 4); font-size: calc(1.125rem * var(--reading-scale, 1)); }

a { color: var(--accent); text-underline-offset: 0.18em; }
:where(a, button, input, select, textarea, summary, [tabindex]):focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

.skip-link { position: absolute; left: 0.75rem; top: -4rem; background: var(--surface); color: var(--text); padding: 0.5rem 0.9rem; font-family: var(--font-sans); z-index: 10; }
.skip-link:focus { top: 0.75rem; }

h1, h2, h3 { font-family: var(--font-serif); font-weight: 700; line-height: 1.15; text-wrap: balance; overflow-wrap: anywhere; scroll-margin-block-start: 1.5rem; }
h1 { font-size: calc(clamp(2.3rem, 5vw, 3.6rem) * var(--reading-scale, 1)); letter-spacing: -0.025em; margin: 0 0 1.5rem; color: var(--primary); }
h2 { font-size: calc(clamp(1.65rem, 2.8vw, 2.2rem) * var(--reading-scale, 1)); letter-spacing: -0.015em; margin: 2.5rem 0 0.9rem; }
h3 { font-size: calc(1.35rem * var(--reading-scale, 1)); margin: 1.8rem 0 0.6rem; }
p, ul, ol, blockquote { margin: 0 0 1.1rem; }
ul, ol { padding-left: 1.4rem; }
li + li { margin-top: 0.35rem; }
blockquote { border-left: 3px solid var(--line); padding-left: 1rem; color: var(--muted); }
code { font-size: 0.9em; background: var(--surface-alt); padding: 0.05em 0.3em; }

/* Header: brand, main navigation, language and palette controls */
.site-header { background: var(--surface); border-bottom: 1px solid var(--line); font-family: var(--font-sans); }
.header-inner { display: flex; flex-wrap: wrap; align-items: center; gap: 0.75rem 1.5rem; min-height: 4.25rem; padding-block: 0.6rem; }
.brand { color: var(--primary); font-family: var(--font-serif); font-size: 1.35rem; font-weight: 700; text-decoration: none; margin-right: auto; }
.site-nav ul, .lang-switch ul { display: flex; flex-wrap: wrap; gap: 0.25rem 1.1rem; list-style: none; margin: 0; padding: 0; }
.site-nav a { color: var(--text); text-decoration: none; font-size: 0.95rem; font-weight: 600; padding-block: 0.4rem; display: inline-block; }
.site-nav a:hover, .site-nav a[aria-current] { color: var(--accent); }
.site-nav a[aria-current] { text-decoration: underline; text-decoration-thickness: 2px; text-underline-offset: 0.45em; }
.header-tools { display: flex; align-items: center; gap: 0.55rem; }
.lang-switch { font-size: 0.85rem; }
.site-nav li + li, .lang-switch li + li { margin-top: 0; }
.lang-switch a, .lang-switch span { display: inline-flex; align-items: center; min-height: 2.75rem; padding: 0.3rem 0; }
.lang-switch span { color: var(--muted); font-weight: 700; }
.language-menu { position: relative; }
.language-menu summary { display: inline-flex; align-items: center; justify-content: center; gap: 0.35rem; min-height: 2.75rem; padding: 0.35rem 0.55rem; border: 1px solid var(--control-border); border-radius: 0.4rem; background: var(--surface); color: var(--text); cursor: pointer; list-style: none; }
.language-menu summary::-webkit-details-marker { display: none; }
.language-menu summary:hover, .language-menu[open] summary { background: var(--surface-alt); }
.lang-switch .language-code { min-height: 0; padding: 0; color: inherit; letter-spacing: 0.04em; }
.disclosure-arrow { transition: transform 0.15s; }
.language-menu[open] .disclosure-arrow { transform: rotate(180deg); }
.lang-switch .language-options { display: grid; position: absolute; inset-inline-end: 0; top: calc(100% + 0.5rem); z-index: 30; min-width: 10rem; max-width: calc(100vw - 2rem); gap: 0.1rem; padding: 0.4rem; background: var(--surface); border: 1px solid var(--control-border); border-radius: 0.4rem; box-shadow: 0 0.6rem 1.5rem #00000026; }
.language-options a, .language-options span { width: 100%; padding: 0.4rem 0.65rem; border-radius: 0.2rem; text-decoration: none; }
.language-options a:hover, .language-options span { background: var(--surface-alt); }
.palette-toggle { display: inline-grid; place-items: center; flex-shrink: 0; width: 2.75rem; height: 2.75rem; border: 1px solid var(--control-border); background: var(--surface); color: var(--text); border-radius: 50%; cursor: pointer; }
.palette-toggle:hover { background: var(--surface-alt); }

/* Editorial markers */
.draft-banner { background: var(--draft-bg); color: var(--draft-text); font-family: var(--font-sans); font-size: 0.9rem; font-weight: 600; padding: 0.6rem 0.9rem; border-left: 4px solid currentColor; }
.badge { display: inline-block; font-family: var(--font-sans); font-size: 0.72rem; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent); border: 1px solid var(--line); padding: 0.1rem 0.45rem; vertical-align: middle; }

/* Collection listings: studies, articles */
.listing { list-style: none; padding: 0; }
.listing li { border-top: 1px solid var(--line); padding: 0.8rem 0; }
.listing li + li { margin-top: 0; }
.listing a { font-weight: 600; }
.listing-note { display: block; color: var(--muted); font-size: 0.9em; }
.listing-empty { color: var(--muted); font-style: italic; }

/* Footer: organizer, responsibility, review date, corrections */
.site-footer { border-top: 1px solid var(--line); background: var(--surface); color: var(--muted); font-family: var(--font-sans); font-size: 0.85rem; }
.footer-inner { display: flex; flex-wrap: wrap; gap: 0.25rem 2rem; padding-block: 1.4rem; }
.footer-inner p { margin: 0; }
.footer-inner p:empty { display: none; }

/* Root language choice */
.language-list { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 1rem; font-family: var(--font-sans); font-size: 1.15rem; }
.language-list a { display: inline-block; padding: 0.6rem 1.2rem; border: 1px solid var(--line); background: var(--surface); text-decoration: none; }

@media (max-width: 40rem) {
  .header-inner { gap: 0.5rem 1rem; }
  .site-nav { order: 3; flex-basis: 100%; }
  .site-nav a { display: inline-flex; align-items: center; min-height: 2.75rem; }
  .header-tools { flex-wrap: wrap; margin-left: auto; }
}

@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }

/* References: filters and list */
.ref-filters { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 11rem), 1fr)); gap: 0.6rem 1rem;
  margin: 1.5rem 0 0.5rem; padding: 1rem; background: var(--surface-alt); border: 1px solid var(--line); border-radius: 6px; }
.ref-filters label { display: flex; flex-direction: column; gap: 0.25rem; font-family: var(--font-sans); font-size: 0.9rem; color: var(--muted); }
.ref-filters input, .ref-filters select { font: inherit; color: var(--text); background: var(--surface);
  border: 1px solid var(--control-border); border-radius: 4px; padding: 0.5rem; min-width: 0; min-height: 2.75rem; }
.ref-count { grid-column: 1 / -1; margin: 0; font-family: var(--font-sans); font-size: 0.9rem; color: var(--muted); }
.ref-filters:not([hidden]) + .ref-total { display: none; }
.ref-total { color: var(--muted); font-family: var(--font-sans); font-size: 0.85em; }
.ref-list { list-style: none; padding: 0; margin: 1rem 0 0; }
.ref { border-top: 1px solid var(--line); padding: 0.75rem 0; }
.ref[hidden] { display: none; }
.ref-citation { display: block; overflow-wrap: anywhere; }
.ref-links { display: block; margin-top: 0.25rem; font-family: var(--font-sans); font-size: 0.85em; overflow-wrap: anywhere; }
.ref-meta { display: block; margin-top: 0.2rem; color: var(--muted); font-family: var(--font-sans); font-size: 0.8em; }

/* Fixed reading tools: the surrounding area does not intercept page clicks. */
.page-controls { position: fixed; left: max(1rem, env(safe-area-inset-left, 0px)); right: max(1rem, env(safe-area-inset-right, 0px)); bottom: calc(1rem + env(safe-area-inset-bottom, 0px)); display: grid; grid-template-columns: 3rem minmax(0, 1fr) 3rem; align-items: center; gap: 0.5rem; z-index: 20; pointer-events: none; }
.page-controls > * { pointer-events: auto; }
.floating-control { display: inline-grid; place-items: center; width: 3rem; height: 3rem; border: 1px solid var(--control-border); border-radius: 0.7rem; background: var(--surface); color: var(--primary); text-decoration: none; box-shadow: 0 0.2rem 0.8rem #00000018; }
.floating-control:hover { background: var(--surface-alt); }
.control-home { grid-column: 1; }
.control-top { grid-column: 3; }
.reading-size { grid-column: 2; justify-self: center; display: flex; align-items: center; gap: 8px; width: 100%; max-width: 14rem; min-width: 0; height: 3rem; padding: 0 10px; border: 1px solid var(--control-border); border-radius: 0.7rem; background: var(--surface); color: var(--text); font: 12px/1.2 var(--font-sans); box-shadow: 0 0.2rem 0.8rem #00000018; }
.reading-size label { flex-shrink: 0; font-size: 16px; }
.reading-size input { flex: 1; min-width: 0; width: 100%; height: 2.75rem; margin: 0; accent-color: var(--primary); cursor: pointer; }
.reading-size output { flex: 0 0 36px; text-align: end; white-space: nowrap; font-variant-numeric: tabular-nums; }
@media (max-width: 25rem) {
  .reading-size { gap: 4px; padding-inline: 6px; }
  .reading-size label { display: none; }
}

/* Equations remain readable as TeX without JavaScript. */
.math-display { max-width: 100%; overflow-x: auto; padding: 0.75rem 0; margin-block: 1.25rem; }
.math-display mjx-container { margin: 0 !important; }
.math-inline { overflow-wrap: normal; }

@media print {
  body { padding-bottom: 0; }
  .page-controls, .header-tools { display: none; }
  .math-display { overflow: visible; }
}