/* Studio utility-site template: base, layout and shared components.
   Requires tokens.css. No colour literals here: tokens only. */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
  .btn:hover, .back-to-top:hover, .back-to-top.is-visible:hover { transform: none !important; }
}
body {
  margin: 0; font-family: var(--font-sans); font-size: var(--fs-base); line-height: var(--lh-base);
  color: var(--c-text); background: var(--c-bg);
  display: flex; flex-direction: column; min-height: 100vh;
}
main { flex: 1 0 auto; }
img, svg { max-width: 100%; height: auto; display: block; }
h1, h2, h3 { line-height: var(--lh-tight); margin: 0 0 var(--space-md); color: var(--c-text); }
h1 { font-size: var(--fs-h1); letter-spacing: -0.01em; }
h2 { font-size: var(--fs-xl); }
h3 { font-size: var(--fs-lg); }
p, ul, ol, dl, table, pre, figure, details { margin: 0 0 var(--space-md); }
/* zero last-child margins */
:where(section, .container, .card, details, li, dd, figure, form, fieldset, .prose) > :last-child { margin-bottom: 0; }
.prose { max-width: var(--measure); }
a { color: var(--c-brand); text-underline-offset: 0.15em; }
a:hover { color: var(--c-brand-strong); }
:focus-visible { outline: 3px solid var(--c-focus); outline-offset: 2px; border-radius: var(--radius-sm); }
code, kbd { font-family: var(--font-mono); font-size: 0.95em; }

.sr-only {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link { position: absolute; left: var(--space-md); top: -10rem; z-index: 100;
  background: var(--c-surface); color: var(--c-brand); padding: var(--space-xs) var(--space-md);
  border: var(--border-w) solid var(--c-brand); border-radius: var(--radius-sm); }
.skip-link:focus { top: var(--space-md); }

/* Layout: one container edge */
.container { width: 100%; max-width: var(--container); margin-inline: auto; padding-inline: var(--gutter); }
/* when gutter is inside, content edge = 70rem minus gutters on wide screens: keep consistent everywhere */
.section { padding-block: var(--section-pad); }
.section--alt { background: var(--c-bg-alt); }
.section__intro { max-width: var(--measure); margin-bottom: var(--space-lg); }
.lead { font-size: var(--fs-lg); color: var(--c-text-muted); max-width: var(--measure); }

/* Header */
.site-header { background: var(--c-surface); border-bottom: var(--border-w) solid var(--c-border-soft); container: site-header / inline-size; }
/* Mobile-first: when brand + nav don't fit (narrow screens or large default text), nav sits on its
   own full-width row under the logo, separated by a hairline. One row once the header is >= 21rem. */
.site-header__inner { display: flex; flex-direction: column; align-items: stretch; gap: 0; }
.site-header__inner > .brand { align-self: flex-start; padding-block: var(--space-xs); }
.site-nav { border-top: var(--border-w) solid var(--c-border-soft); }
.site-nav ul { justify-content: flex-start; flex-wrap: wrap; column-gap: var(--space-lg); }
@container site-header (min-width: 21rem) {
  .site-header__inner { flex-direction: row; align-items: center; justify-content: space-between; gap: var(--space-md); min-height: 4rem; }
  .site-header__inner > .brand { align-self: center; padding-block: 0; }
  .site-nav { border-top: 0; }
  .site-nav ul { flex-wrap: nowrap; column-gap: var(--space-md); }
}
.brand { display: inline-flex; min-width: 0; align-items: center; gap: var(--space-xs); font-weight: 700;
  font-size: var(--fs-lg); color: var(--c-text); text-decoration: none; line-height: 1; min-height: var(--control-h); }
.brand img { width: 2rem; height: 2rem; }
.site-nav ul { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; }
.site-nav a { display: inline-flex; align-items: center; min-height: var(--touch-min); font-weight: 600; }
.site-nav a[aria-current] { text-decoration-thickness: 0.15em; color: var(--c-brand-strong); }

/* Buttons: one global style */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-xs);
  min-height: var(--btn-h); padding: 0 var(--control-pad-x); border-radius: var(--radius-pill);
  border: var(--border-w) solid var(--c-cta); background: var(--c-cta); color: var(--c-on-cta);
  font: inherit; font-weight: 600; line-height: 1.2; text-decoration: none; cursor: pointer;
  transition: background-color var(--dur), border-color var(--dur), transform var(--dur), box-shadow var(--dur);
}
.btn:hover { background: var(--c-cta-hover); border-color: var(--c-cta-hover); color: var(--c-on-cta);
  transform: translateY(var(--lift)); box-shadow: var(--shadow-md); }
.btn:active { transform: none; box-shadow: none; }
.btn--ghost { background: var(--c-surface); color: var(--c-cta); }
.btn--ghost:hover { background: var(--c-cta-hover); color: var(--c-on-cta); }
.btn--sm { padding-inline: var(--space-sm); font-size: var(--fs-sm); }
.btn[disabled] { opacity: 0.6; cursor: not-allowed; transform: none; box-shadow: none; }

/* Inputs */
.field { display: flex; flex-direction: column; gap: var(--space-2xs); min-width: 0; }
.field label, .field .label { font-weight: 600; }
.field__hint { font-size: var(--fs-sm); color: var(--c-text-muted); margin: 0; }
.input-wrap { display: flex; align-items: center; min-height: var(--control-h);
  border: var(--border-w) solid var(--c-border); border-radius: var(--radius-md); background: var(--c-surface);
  padding-inline: var(--control-pad-x); gap: var(--space-xs); }
.input-wrap:focus-within { outline: 3px solid var(--c-focus); outline-offset: 2px; }
.input-wrap__affix { color: var(--c-text-muted); font-weight: 600; flex: none; }
.input-wrap input, .input { flex: 1 1 auto; min-width: 0; min-height: calc(var(--control-h) - 2 * var(--border-w));
  border: 0; background: transparent; font: inherit; color: var(--c-text); padding: 0; }
.input-wrap input:focus { outline: none; }
.input-wrap[data-invalid="true"] { border-color: var(--c-error); border-width: 2px; }
.field__error { color: var(--c-error); font-size: var(--fs-sm); font-weight: 600; margin: 0; }
.field__error:empty { display: none; }

/* Segmented radio control */
.segmented { display: flex; flex-wrap: wrap; gap: var(--space-xs); border: 0; padding: 0; margin: 0; }
.segmented legend { font-weight: 600; margin-bottom: var(--space-2xs); padding: 0; }
.segmented label { display: inline-flex; align-items: center; gap: var(--space-xs); min-height: var(--control-h);
  padding-inline: var(--control-pad-x); border: var(--border-w) solid var(--c-border); border-radius: var(--radius-pill);
  background: var(--c-surface); cursor: pointer; font-weight: 600; }
.segmented input { accent-color: var(--c-brand); width: 1.125rem; height: 1.125rem; margin: 0; }
.segmented label:has(input:checked) { background: var(--c-brand-tint); border-color: var(--c-brand); border-width: 2px; }
.segmented label:has(input:focus-visible) { outline: 3px solid var(--c-focus); outline-offset: 2px; }

/* Cards */
.card { background: var(--c-surface); border: var(--border-w) solid var(--c-border-soft); border-radius: var(--radius-lg);
  padding: clamp(1rem, 0.6rem + 2vw, 2rem); box-shadow: var(--shadow-sm); }

/* FAQ */
.faq { display: grid; gap: var(--space-sm); max-width: 70ch; }
.faq details { background: var(--c-surface); border: var(--border-w) solid var(--c-border-soft); border-radius: var(--radius-md); }
.faq summary { display: flex; align-items: center; justify-content: space-between; gap: var(--space-md);
  min-height: var(--control-h); padding: var(--space-sm) var(--control-pad-x); cursor: pointer; font-weight: 600; list-style: none; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-size: var(--fs-lg); line-height: 1; color: var(--c-brand); flex: none; }
.faq details[open] summary::after { content: "\2212"; }
.faq .faq__body { padding: 0 var(--control-pad-x) var(--space-md); }
.faq .faq__body > :last-child { margin-bottom: 0; }

/* Citations */
.cite { font-size: var(--fs-sm); color: var(--c-text-muted); }

/* Related tools */
.tool-grid { display: grid; gap: var(--space-md); grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr));
  list-style: none; padding: 0; margin: 0; }
.tool-grid li { margin: 0; }
.tool-card { height: 100%; display: flex; flex-direction: column; gap: var(--space-xs); }
.tool-card h3 { margin: 0; font-size: var(--fs-base); }
.tool-card p { margin: 0; color: var(--c-text-muted); font-size: var(--fs-sm); }
.badge { align-self: flex-start; font-size: var(--fs-xs); font-weight: 700; padding: 0.125rem var(--space-xs);
  border-radius: var(--radius-pill); background: var(--c-brand-tint); color: var(--c-brand-strong); }

/* Ad slots: hidden until ads are enabled AND consented (html.ads-on is set before first paint
   from the stored choice, so returning visitors get no layout shift). Reserved height avoids CLS. */
.ad-slot { display: none; }
.ads-on .ad-slot { display: block; position: relative; min-height: var(--ad-min-h); margin-block: var(--space-lg);
  padding-top: 1.25rem; background: var(--c-bg-alt); border: var(--border-w) solid var(--c-border-soft); border-radius: var(--radius-md); }
.ads-on .ad-slot::before { content: "Advertisement"; position: absolute; top: var(--space-2xs); left: var(--space-sm);
  font-size: var(--fs-xs); color: var(--c-text-muted); }
.section--alt .ad-slot { background: var(--c-bg); }
.consent-slot:empty { display: none; }

/* Link-styled button (e.g. 'Cookie settings' in the footer bar) */
.link-btn { display: inline-flex; align-items: center; min-height: var(--touch-min); padding: 0; border: 0; background: none;
  font: inherit; color: var(--c-brand-strong); text-decoration: underline; text-underline-offset: 0.15em; cursor: pointer; }
.link-btn:hover { color: var(--c-text); }

/* Breadcrumbs */
.crumbs-wrap { padding-top: var(--space-md); }
.breadcrumbs ol { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2xs) var(--space-xs); list-style: none; margin: 0; padding: 0; font-size: var(--fs-sm); }
.breadcrumbs li { display: inline-flex; align-items: center; gap: var(--space-xs); margin: 0; }
.breadcrumbs li + li::before { content: "/"; color: var(--c-text-muted); }
.breadcrumbs a { display: inline-flex; align-items: center; min-height: var(--touch-min); }
.breadcrumbs [aria-current] { color: var(--c-text-muted); }

/* Article / long-form pages */
.article { max-width: 70ch; }
.article h2 { margin-top: var(--space-xl); }
.article h3 { margin-top: var(--space-lg); }
.article > :first-child { margin-top: 0; }
.article li { margin-bottom: var(--space-2xs); }
.article .meta { font-size: var(--fs-sm); color: var(--c-text-muted); }
.article table, .data-table { width: 100%; border-collapse: collapse; font-variant-numeric: tabular-nums; }
.data-table th, .data-table td { text-align: left; padding: var(--space-xs); border-bottom: var(--border-w) solid var(--c-border-soft); }
.data-table td.num, .data-table th.num { text-align: right; white-space: nowrap; }
.data-table caption { text-align: left; font-weight: 600; padding-bottom: var(--space-xs); }
.table-scroll { overflow-x: auto; position: relative; margin-bottom: var(--space-md); }
.callout { padding: var(--space-md) var(--control-pad-x); border-left: 0.25rem solid var(--c-brand); background: var(--c-bg-alt); border-radius: var(--radius-sm); }
.callout > :last-child { margin-bottom: 0; }
.sources { font-size: var(--fs-sm); }
.card-list { display: grid; gap: var(--space-md); grid-template-columns: repeat(auto-fit, minmax(min(100%, 18rem), 1fr)); list-style: none; padding: 0; margin: 0; }
.card-list li { margin: 0; }
.card-list .card { height: 100%; }
.card-list h2, .card-list h3 { font-size: var(--fs-lg); margin-bottom: var(--space-xs); }

/* Cookie consent banner: fixed (no CLS), utility colour, not modal (no focus trap) */
.consent { position: fixed; inset: auto 0 0 0; z-index: 60; background: var(--c-utility); color: var(--c-on-utility);
  box-shadow: 0 -4px 20px var(--c-shadow); max-height: 80vh; overflow-y: auto; }
.consent[hidden] { display: none; }
.consent__inner { display: flex; flex-direction: column; gap: var(--space-md); padding-block: var(--space-md); }
.consent h2 { color: var(--c-on-utility); font-size: var(--fs-base); margin: 0 0 var(--space-2xs); }
.consent p { margin: 0; font-size: var(--fs-sm); }
.consent a { color: var(--c-on-utility); }
.consent :focus-visible { outline-color: var(--c-focus-on-dark); }
.consent__actions { display: flex; flex-direction: column; gap: var(--space-sm); }
.consent__actions .btn { width: 100%; }
@media (min-width: 48rem) {
  .consent__inner { flex-direction: row; align-items: center; justify-content: space-between; }
  .consent__actions { flex-direction: row; flex: none; }
  .consent__actions .btn { width: auto; }
}
.btn--on-utility { background: var(--c-on-utility); color: var(--c-utility); border-color: var(--c-on-utility); }
.btn--on-utility:hover { background: var(--c-on-utility-hover); border-color: var(--c-on-utility-hover); color: var(--c-utility-hover); }
.consent-open .back-to-top { display: none; }

/* Footer */
.site-footer { background: var(--c-bg-footer); }
.site-footer__main { padding-block: var(--section-pad); display: grid; gap: var(--space-lg);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); }
.site-footer__main > * { margin: 0; }
.site-footer h2 { font-size: var(--fs-base); margin-bottom: var(--space-xs); }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: var(--space-2xs); }
.site-footer a { display: inline-flex; align-items: center; min-height: var(--touch-min); }
.site-footer ul { gap: 0; }
.site-footer__bar { background: var(--c-bg-footer-bar); font-size: var(--fs-xs); color: var(--c-text); }
.site-footer__bar .container { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: var(--space-xs) var(--space-md); padding-block: var(--space-sm); }
.site-footer__bar p { margin: 0; }

/* Back to top: dedicated utility colour */
.back-to-top { position: fixed; right: var(--space-md); bottom: var(--space-md); z-index: 50;
  display: inline-flex; align-items: center; justify-content: center; width: var(--btn-h); height: var(--btn-h);
  border-radius: var(--radius-pill); border: 2px solid var(--c-on-utility); background: var(--c-utility); color: var(--c-on-utility);
  box-shadow: var(--shadow-md); cursor: pointer; opacity: 0; visibility: hidden; transform: translateY(0.5rem);
  transition: opacity var(--dur), transform var(--dur), visibility var(--dur), background-color var(--dur); }
.back-to-top.is-visible { opacity: 1; visibility: visible; transform: none; }
.back-to-top:hover { background: var(--c-utility-hover); color: var(--c-on-utility); transform: translateY(var(--lift)); }
.back-to-top:focus-visible { outline: 3px solid var(--c-focus); outline-offset: 3px; background: var(--c-utility-hover); }
.back-to-top svg { width: 1.25rem; height: 1.25rem; }

[hidden] { display: none !important; }
/* Mobile-first visibility helper: hidden on small screens, shown from 30rem */
.hide-sm { display: none !important; }
@media (min-width: 30rem) { .hide-sm { display: revert !important; } }

/* Button row: all buttons on one row if they fit, otherwise stacked full width (never a 2+1 wrap).
   Threshold is a container query in rem, so it also adapts to the user's default font size.
   --row-min = width needed for the row; set per instance (default 24rem). */
.btn-row { container-type: inline-size; }
.btn-row__inner { display: flex; flex-direction: column; align-items: stretch; gap: var(--space-sm); }
.btn-row__inner > .btn { width: 100%; }
@container (min-width: 24rem) {
  .btn-row__inner { flex-direction: row; flex-wrap: nowrap; align-items: center; }
  .btn-row__inner > .btn { width: auto; }
}
/* Pairs need less room: .btn-row--pair goes to one row from 14rem */
@container (min-width: 14rem) {
  .btn-row--pair .btn-row__inner { flex-direction: row; align-items: center; }
  .btn-row--pair .btn-row__inner > .btn { width: auto; }
}

/* Notice / placeholder block */
.notice { max-width: var(--measure); padding: var(--space-md) var(--control-pad-x); border-left: 0.25rem solid var(--c-brand);
  background: var(--c-surface); border-radius: var(--radius-sm); }