/* ==========================================================================
   base.css — document defaults, focus behaviour and small utilities
   ========================================================================== */

body {
  font-family: var(--font-body);
  font-size: var(--size-body);
  font-weight: var(--weight-body);
  line-height: var(--line-height-body);
  color: var(--colour-text);
  background-color: var(--colour-background);
  overflow-x: hidden;
}

/* Prevents background scrolling while the mobile menu or a dialog is open. */
body.is-scroll-locked {
  overflow: hidden;
}

::selection {
  color: var(--colour-text-inverse);
  background-color: var(--colour-primary);
}

/* --- Links ---------------------------------------------------------------- */

a {
  color: inherit;
  text-decoration: none;
}

a:not([class]) {
  color: var(--colour-text);
  text-decoration: underline;
  text-decoration-color: var(--colour-border-strong);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.22em;
  transition: color var(--duration-fast) var(--easing),
    text-decoration-color var(--duration-fast) var(--easing);
}

a:not([class]):hover {
  color: var(--colour-accent);
  text-decoration-color: var(--colour-accent);
}

/* --- Focus ---------------------------------------------------------------- */

:focus-visible {
  outline: 2px solid var(--colour-focus);
  outline-offset: 3px;
  border-radius: 1px;
}

/* Only remove the default ring where a focus-visible ring is provided above. */
:focus:not(:focus-visible) {
  outline: none;
}

/* --- Skip link ------------------------------------------------------------ */

.skip-link {
  position: absolute;
  top: var(--space-sm);
  left: var(--space-sm);
  z-index: var(--z-skip-link);
  padding: var(--space-xs) var(--space-md);
  font-family: var(--font-navigation);
  font-size: var(--size-small);
  font-weight: var(--weight-medium);
  color: var(--colour-text-inverse);
  background-color: var(--colour-primary);
  border-radius: var(--control-radius);
  transform: translateY(calc(-100% - var(--space-lg)));
  transition: transform var(--duration-fast) var(--easing);
}

.skip-link:focus {
  transform: translateY(0);
}

/* --- Utilities ------------------------------------------------------------ */

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.text-muted {
  color: var(--colour-text-muted);
}

.text-accent {
  color: var(--colour-accent);
}

.text-centre {
  text-align: center;
}

.no-wrap {
  white-space: nowrap;
}

/* --- Reveal on scroll ----------------------------------------------------- */
/* Progressive enhancement: content is visible unless JS marks it observable. */

[data-reveal] {
  opacity: 1;
}

.js-reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(1.25rem);
  transition: opacity var(--duration-slow) var(--easing-emphasis),
    transform var(--duration-slow) var(--easing-emphasis);
}

.js-reveal-ready [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

.js-reveal-ready [data-reveal-delay='1'] { transition-delay: 90ms; }
.js-reveal-ready [data-reveal-delay='2'] { transition-delay: 180ms; }
.js-reveal-ready [data-reveal-delay='3'] { transition-delay: 270ms; }
.js-reveal-ready [data-reveal-delay='4'] { transition-delay: 360ms; }

@media (prefers-reduced-motion: reduce) {
  .js-reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* --- Print ---------------------------------------------------------------- */

@media print {
  body {
    font-size: 11pt;
    color: #000;
    background: #fff;
  }

  .site-header,
  .site-footer,
  .skip-link,
  .article-toc,
  .article-nav,
  .cta,
  .cookie-banner,
  [data-print='hide'] {
    display: none !important;
  }

  a[href^='http']::after {
    content: ' (' attr(href) ')';
    font-size: 9pt;
    word-break: break-all;
  }

  .section,
  .article-body > * {
    break-inside: avoid;
  }
}