/* Coincidence — design tokens and base styles.
   "Scientific field notebook meets humane long-form magazine." */

@layer tokens, reset, layout, components, utilities;

@layer tokens {
  :root {
    /* Neutrals: warm paper-like canvas, dark ink. */
    --color-canvas: #f4efe6;
    --color-surface: #fffdf8;
    --color-ink: #23201b;
    --color-muted: #5b5448;
    --color-border: #d8cfbd;

    /* One cool analytical accent, one restrained highlight. */
    --color-accent: #2b5d72;
    --color-accent-hover: #1f4758;
    --color-highlight: #8a4b2e;
    --color-focus: #1b6ef3;

    --color-success: #2f6b3a;
    --color-warning: #8a5a00;
    --color-disputed: #8a2e2e;

    --font-serif: "Source Serif 4", Georgia, "Times New Roman", serif;
    --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;

    --step--1: clamp(0.8rem, 0.78rem + 0.1vw, 0.875rem);
    --step-0: clamp(1rem, 0.95rem + 0.2vw, 1.0625rem);
    --step-1: clamp(1.125rem, 1.05rem + 0.4vw, 1.3125rem);
    --step-2: clamp(1.4rem, 1.25rem + 0.8vw, 1.75rem);
    --step-3: clamp(1.75rem, 1.5rem + 1.4vw, 2.375rem);
    --step-4: clamp(2.1rem, 1.7rem + 2.2vw, 3.25rem);

    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-12: 3rem;
    --space-16: 4rem;

    --prose-width: 42rem;
    --wide-width: 72rem;

    --border-width: 1px;
    --radius: 0.35rem;
    --motion-fast: 120ms;
    --motion-base: 200ms;
  }

  @media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
      --color-canvas: #181512;
      --color-surface: #201c18;
      --color-ink: #ece6da;
      --color-muted: #b8ae9c;
      --color-border: #3a342b;
      --color-accent: #79b6d1;
      --color-accent-hover: #9ccbe2;
      --color-highlight: #e0a06b;
      --color-focus: #6fb1ff;
    }
  }

  :root[data-theme="dark"] {
    --color-canvas: #181512;
    --color-surface: #201c18;
    --color-ink: #ece6da;
    --color-muted: #b8ae9c;
    --color-border: #3a342b;
    --color-accent: #79b6d1;
    --color-accent-hover: #9ccbe2;
    --color-highlight: #e0a06b;
    --color-focus: #6fb1ff;
  }
}

@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  html { color-scheme: light dark; -webkit-text-size-adjust: 100%; }
  body {
    margin: 0;
    background: var(--color-canvas);
    color: var(--color-ink);
    font-family: var(--font-serif);
    font-size: var(--step-0);
    line-height: 1.6;
  }
  img, svg { max-width: 100%; display: block; }
  a { color: var(--color-accent); }
  a:hover { color: var(--color-accent-hover); }
  :focus-visible {
    outline: 3px solid var(--color-focus);
    outline-offset: 2px;
  }

  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
      animation-duration: 0.001ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.001ms !important;
    }
  }
}

@layer layout {
  .wrap {
    width: min(100% - 2 * var(--space-4), var(--wide-width));
    margin-inline: auto;
  }
  .wrap--prose {
    width: min(100% - 2 * var(--space-4), var(--prose-width));
  }

  .table-scroll {
    overflow-x: auto;
  }

  .skip-link {
    position: absolute;
    left: -9999px;
    top: 0;
    background: var(--color-accent);
    color: #fff;
    padding: var(--space-2) var(--space-4);
    z-index: 100;
  }
  .skip-link:focus {
    left: var(--space-4);
    top: var(--space-4);
  }

  .site-header {
    border-bottom: var(--border-width) solid var(--color-border);
    background: var(--color-surface);
  }
  .site-header__bar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
    padding-block: var(--space-4);
  }
  .site-header__brand {
    display: flex;
    flex-direction: column;
    text-decoration: none;
    color: var(--color-ink);
  }
  .site-header__name {
    font-family: var(--font-sans);
    font-weight: 700;
    font-size: var(--step-1);
  }
  .site-header__strapline {
    font-size: var(--step--1);
    color: var(--color-muted);
  }
  /* The toggle button is invisible until nav-toggle.js confirms it can
     run (adding `js-nav` to <html>) — so a no-JS visitor never sees a
     button that does nothing, and always gets the plain, always-visible
     nav below rather than one hidden behind a broken control. */
  .nav-toggle {
    display: none;
    align-items: center;
    gap: var(--space-2);
    margin-left: auto;
    padding: var(--space-2);
    cursor: pointer;
    background: none;
    border: none;
    font-family: var(--font-sans);
    font-size: var(--step--1);
    color: var(--color-ink);
    border-radius: var(--radius);
  }
  @media (max-width: 640px) {
    .js-nav .nav-toggle {
      display: flex;
    }
  }
  .nav-toggle:hover { color: var(--color-accent); }
  .nav-toggle__icon,
  .nav-toggle__icon::before,
  .nav-toggle__icon::after {
    display: block;
    width: 1.25rem;
    height: 2px;
    background: currentColor;
    border-radius: 1px;
  }
  .nav-toggle__icon {
    position: relative;
  }
  .nav-toggle__icon::before,
  .nav-toggle__icon::after {
    content: "";
    position: absolute;
    left: 0;
  }
  .nav-toggle__icon::before { top: -6px; }
  .nav-toggle__icon::after { top: 6px; }

  .site-nav__list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
    margin: 0;
    padding: 0;
    font-family: var(--font-sans);
    font-size: var(--step--1);
  }
  .site-nav__list a {
    text-decoration: none;
    padding: var(--space-1) 0;
    border-bottom: 2px solid transparent;
  }
  .site-nav__list a:hover,
  .site-nav__list a[aria-current="page"] {
    border-bottom-color: var(--color-accent);
  }

  /* Only once JS confirms the toggle button works (see nav-toggle.js) does
     the nav collapse behind it on narrow screens; otherwise every width
     gets the plain, always-visible nav above. */
  @media (max-width: 640px) {
    .js-nav .site-nav {
      display: none;
      width: 100%;
      margin-top: var(--space-2);
      padding-top: var(--space-3);
      border-top: var(--border-width) solid var(--color-border);
    }
    .js-nav .site-nav.is-open {
      display: block;
    }
    .js-nav .site-nav__list {
      flex-direction: column;
      gap: var(--space-1);
    }
    .js-nav .site-nav__list a {
      display: block;
      padding: var(--space-2) 0;
    }
  }

  .site-footer {
    margin-top: var(--space-16);
    border-top: var(--border-width) solid var(--color-border);
    background: var(--color-surface);
    padding-block: var(--space-8);
    font-family: var(--font-sans);
    font-size: var(--step--1);
    color: var(--color-muted);
  }
  .site-footer__list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
    margin: 0 0 var(--space-4);
    padding: 0;
  }
}

@layer components {
  .article { padding-block: var(--space-8) var(--space-16); }
  .article__header { margin-bottom: var(--space-6); }
  .article__dek {
    font-size: var(--step-1);
    color: var(--color-muted);
  }
  .article__dates {
    font-family: var(--font-sans);
    font-size: var(--step--1);
    color: var(--color-muted);
  }
  .article__body h2 { margin-top: var(--space-12); }
  .article__body :is(h2, h3) + * { margin-top: var(--space-3); }

  .breadcrumbs__list {
    list-style: none;
    display: flex;
    gap: var(--space-2);
    padding: 0;
    margin: 0 0 var(--space-4);
    font-family: var(--font-sans);
    font-size: var(--step--1);
    color: var(--color-muted);
  }
  .breadcrumbs__list li:not(:last-child)::after {
    content: "/";
    margin-left: var(--space-2);
  }

  .evidence-badge {
    display: inline-flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: var(--space-2);
    font-family: var(--font-sans);
    font-size: var(--step--1);
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    padding: var(--space-2) var(--space-3);
    margin: var(--space-3) 0;
  }
  .evidence-badge__text {
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.03em;
  }
  .evidence-badge__text::before { content: "● "; }
  .evidence-badge--established .evidence-badge__text { color: var(--color-success); }
  .evidence-badge--contested .evidence-badge__text,
  .evidence-badge--speculative .evidence-badge__text { color: var(--color-warning); }
  .evidence-badge--anecdotal .evidence-badge__text,
  .evidence-badge--historical-cultural .evidence-badge__text { color: var(--color-muted); }

  .verification-badge--verified .evidence-badge__text { color: var(--color-success); }
  .verification-badge--mixed .evidence-badge__text,
  .verification-badge--disputed .evidence-badge__text { color: var(--color-warning); }
  .verification-badge--false .evidence-badge__text { color: var(--color-disputed); }
  .verification-badge--unresolved .evidence-badge__text { color: var(--color-muted); }

  .claim-vs-record {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
    gap: var(--space-4);
    margin: var(--space-6) 0;
  }
  .claim-vs-record__box {
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    padding: var(--space-4);
    background: var(--color-surface);
  }
  .claim-vs-record__heading {
    font-family: var(--font-sans);
    font-size: var(--step--1);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    margin: 0 0 var(--space-2);
  }
  .claim-vs-record__box--claim .claim-vs-record__heading { color: var(--color-muted); }
  .claim-vs-record__box--record .claim-vs-record__heading { color: var(--color-accent); }
  .claim-vs-record__box > :last-child { margin-bottom: 0; }

  .citation-list { margin-top: var(--space-12); font-size: var(--step--1); }
  .citation-list__items { padding-left: 1.4em; }
  .citation-list__item { margin-bottom: var(--space-2); }
  .citation-list__item--missing { color: var(--color-disputed); }
  .citation-ref { text-decoration: underline; }

  .topic-tags {
    margin-top: var(--space-6);
    font-family: var(--font-sans);
  }
  .topic-tags ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    padding: 0;
    margin: 0;
  }
  .topic-tags a {
    display: inline-block;
    font-size: var(--step--1);
    text-decoration: none;
    padding: var(--space-1) var(--space-3);
    border: var(--border-width) solid var(--color-border);
    border-radius: 999px;
    color: var(--color-muted);
  }
  .topic-tags a:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
  }

  .button {
    display: inline-block;
    font-family: var(--font-sans);
    background: var(--color-accent);
    color: #fff;
    text-decoration: none;
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius);
  }
  .button:hover { background: var(--color-accent-hover); color: #fff; }

  .home-hero { padding-block: var(--space-12); }
  .home-hero__strapline {
    font-family: var(--font-sans);
    color: var(--color-highlight);
    font-size: var(--step-1);
  }
  .home-links { padding-block: var(--space-8) var(--space-16); }
  .home-links__grid {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
    gap: var(--space-6);
    padding: 0;
  }
  .home-links__grid a {
    font-family: var(--font-sans);
    font-weight: 700;
    text-decoration: none;
  }
  .home-links__grid p {
    margin-top: var(--space-1);
    color: var(--color-muted);
    font-size: var(--step--1);
  }

  .bibliography-list { padding-left: 1.4em; }
  .bibliography-list li { margin-bottom: var(--space-4); }

  .interactive-shell {
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    padding: var(--space-6);
    margin: var(--space-6) 0;
    font-family: var(--font-sans);
  }
  .interactive-controls {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
    gap: var(--space-4);
    align-items: end;
  }
  .interactive-controls__field {
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
    font-size: var(--step--1);
  }
  .interactive-controls__pair {
    display: flex;
    gap: var(--space-2);
    align-items: center;
  }
  .interactive-controls__pair input[type="number"] { width: 6rem; }
  .interactive-controls input,
  .interactive-controls button {
    font: inherit;
    padding: var(--space-2);
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-canvas);
    color: var(--color-ink);
  }
  .interactive-controls input[type="range"] { padding: 0; border: none; background: none; }
  .interactive-controls button {
    cursor: pointer;
    background: var(--color-surface);
  }
  .interactive-controls button:hover { background: var(--color-canvas); }
  .interactive-controls > .button {
    grid-column: 1 / -1;
    justify-self: start;
    border: none;
  }
  .interactive-results {
    margin-top: var(--space-6);
    padding-top: var(--space-4);
    border-top: var(--border-width) solid var(--color-border);
    font-size: var(--step-0);
  }
  .interactive-results [data-output="live"] {
    font-weight: 700;
  }

  .filter-nav {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    margin: var(--space-4) 0;
    font-family: var(--font-sans);
    font-size: var(--step--1);
  }
  .filter-nav a {
    padding: var(--space-1) var(--space-3);
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    color: var(--color-ink);
    text-decoration: none;
  }
  .filter-nav a:hover {
    background: var(--color-canvas);
  }
  .filter-nav a[aria-current="true"] {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: var(--color-surface);
    font-weight: 700;
  }
  .filter-nav__count {
    font-family: var(--font-sans);
    font-size: var(--step--1);
    color: var(--color-muted);
  }

  .search-box {
    margin: var(--space-6) 0;
    font-family: var(--font-sans);
  }
  .search-box label {
    display: block;
    font-weight: 700;
    margin-bottom: var(--space-2);
  }
  #search-input {
    width: 100%;
    font: inherit;
    font-size: var(--step-1);
    padding: var(--space-3);
    border: var(--border-width) solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    color: var(--color-ink);
  }
  .search-box__status {
    font-size: var(--step--1);
    color: var(--color-muted);
    margin-top: var(--space-2);
  }
  .search-box__results {
    list-style: none;
    padding: 0;
    margin: var(--space-4) 0 0;
  }
  .search-box__results li {
    padding: var(--space-3) 0;
    border-bottom: var(--border-width) solid var(--color-border);
  }
  .search-box__results a {
    font-weight: 700;
  }
  .search-browse-list {
    padding-left: 1.4em;
  }
  .search-browse-list li {
    margin-bottom: var(--space-2);
  }
}

@layer utilities {
  .visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }
}