/* Reading width module — doc measure tokens + control chrome.
   Place {{> adt-read-width}} anywhere; demo places it in .adt-tool-band (outside the 3-col row).
   data-adt-read-width only changes --adt-doc-max. Layout sizes main to the doc; --adt-col-gap stays fixed. */

:root {
  /* Constant nav↔doc / doc↔TOC gap (does not scale with reading width) */
  --adt-col-gap: 2rem;
  --adt-doc-max: 82ch;
  --adt-read-width-radius: 0.4rem;
  --adt-read-width-radius-sm: 0.25rem;
  --adt-read-width-border: var(--adt-border, #d9dee7);
  --adt-read-width-bg: var(--adt-elevated, #fff);
  --adt-read-width-fg: var(--adt-ink-muted, #5a6270);
  --adt-read-width-fg-active: var(--adt-accent, #0f766e);
  --adt-read-width-soft: var(--adt-accent-soft, rgba(15, 118, 110, 0.1));
  --adt-read-width-ink: var(--adt-ink, #141820);
  --adt-read-width-transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

html[data-adt-read-width="narrow"] {
  --adt-doc-max: 68ch;
}

html[data-adt-read-width="comfortable"],
html:not([data-adt-read-width]) {
  --adt-doc-max: 82ch;
}

html[data-adt-read-width="wide"] {
  --adt-doc-max: 100ch;
}

@media screen and (min-width: 1024px) {
  /*
   * Center column tracks --adt-doc-max. Side panels stay at fixed widths with a
   * constant --adt-col-gap; widening the doc moves panels outward only because
   * the content column grew — no flex slack between nav and the text.
   *
   * flex-basis: auto (not var(--adt-doc-max)): the flex base size follows the
   * transitioning `width`. A jumped flex-basis made shrink snap while grow still
   * looked smooth via max-width.
   */
  main.adt-article {
    flex: 0 1 auto;
    width: var(--adt-doc-max);
    max-width: var(--adt-doc-max);
    min-width: 0;
    transition: width 0.25s ease, max-width 0.25s ease;
  }

  .doc {
    max-width: 100% !important;
    width: 100%;
    margin-inline: 0 !important;
  }
}

/* Control — placement-agnostic */
.adt-read-width {
  display: inline-flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  gap: 0.1rem;
  padding: 0.15rem;
  border: 1px solid var(--adt-read-width-border);
  border-radius: var(--adt-read-width-radius);
  background: var(--adt-read-width-bg);
  box-sizing: border-box;
}

/* Demo / tool-band placement: centered over the article column; shares --adt-tool-band height */
.adt-tool-band-center > .adt-read-width,
article.doc > .adt-read-width {
  display: flex;
  width: fit-content;
  max-width: 100%;
  min-height: var(--adt-tool-band, 2.15rem);
  margin: 0;
  box-sizing: border-box;
}

article.doc > .adt-read-width {
  margin: 0 auto var(--adt-tool-gap, 0.65rem);
}

.adt-read-width-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.85rem;
  height: 1.85rem;
  padding: 0;
  border: none;
  border-radius: var(--adt-read-width-radius-sm);
  background: transparent;
  color: var(--adt-read-width-fg);
  cursor: pointer;
  transition: var(--adt-read-width-transition);
}

.adt-read-width-btn:hover {
  color: var(--adt-read-width-ink);
  background: var(--adt-read-width-soft);
}

.adt-read-width-btn[aria-pressed="true"] {
  color: var(--adt-read-width-fg-active);
  background: var(--adt-read-width-soft);
}

.adt-read-width-btn:focus {
  outline: none;
}

.adt-read-width-btn:focus-visible {
  outline: 2px solid var(--adt-read-width-fg-active);
  outline-offset: 1px;
}

.adt-read-width-btn svg {
  width: 16px;
  height: 16px;
  display: block;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.75;
  stroke-linecap: round;
}

/* Below the 3-col / doc-measure breakpoint, width control is a no-op — hide it. */
@media screen and (max-width: 1023.5px) {
  .adt-read-width {
    display: none !important;
  }

  /* Collapse the tool band when only (hidden) read-width is present. */
  .adt-tool-band:has(.adt-read-width):not(:has(.adt-font-size)) {
    display: none;
  }
}