/* Header, footer, skip link and preview banner of every lernapps.net site (frame.js renders the HTML).
   Plain CSS on the tokens (tokens.css, linked before this file), so that sites without a CSS framework
   (docs) look the same. Prefix: la-. */

.la-skip {
  position: absolute;
  left: -9999px;
}
.la-skip:focus {
  position: fixed;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 1000;
  padding: 0.5rem 1rem;
  background: #fff;
  color: #1d4ed8; /* blue-700 on white, in the dark mode too: not the (light) link token */
  font: 600 1rem var(--la-font);
  border-radius: var(--la-radius);
  box-shadow: 0 2px 8px rgb(0 0 0 / 0.25);
}

.la-preview {
  margin: 0;
  padding: 0.5rem var(--la-gutter);
  background: var(--la-preview);
  color: var(--la-ink);
  font: 0.875rem/1.4 var(--la-font);
  text-align: center;
}
.la-preview a {
  color: inherit;
  text-decoration: underline;
}

/* A page shown in another language than the frame's: one line above the content. */
.la-fallback {
  margin: 0;
  padding: 0.5rem var(--la-gutter);
  background: var(--la-fallback);
  color: var(--la-ink);
  font: 0.875rem/1.4 var(--la-font);
  text-align: center;
}

.la-header,
.la-footer {
  background: var(--la-ink);
  color: var(--la-on-ink);
  font-family: var(--la-font);
  line-height: 1.5;
}
.la-header__inner,
.la-footer__inner {
  box-sizing: border-box;
  max-width: var(--la-width);
  margin: 0 auto;
  padding: 0 var(--la-gutter);
}
.la-header__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  column-gap: 1.5rem; /* the row of links just fits the width of the header on a wide screen: keep it one row */
}
.la-brand {
  display: flex;
  align-items: flex-end;
  gap: 14px;
  padding: 1rem 0;
  color: var(--la-on-ink);
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1;
  text-decoration: none;
}
.la-brand img {
  height: 1.25em;
  margin-bottom: -0.12em;
}
.la-brand__tld {
  color: var(--la-accent);
}
.la-nav ul,
.la-footer ul {
  display: flex;
  flex-wrap: wrap;
  margin: 0;
  padding: 0;
  list-style: none;
}
.la-nav ul {
  column-gap: 1.5rem;
  row-gap: 0.25rem;
  font-size: 0.875rem;
}
.la-nav a {
  display: inline-block;
  padding: 0.5rem 0;
  color: var(--la-on-ink-muted);
  text-decoration: none;
}
.la-nav a:hover,
.la-nav a[aria-current] {
  color: var(--la-on-ink);
}
.la-nav a[aria-current] {
  font-weight: 600;
}
.la-footer {
  margin-top: 4rem;
  color: var(--la-on-ink-muted);
  font-size: 0.875rem;
}
.la-footer__inner {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding-top: 2rem;
  padding-bottom: 2rem;
}
.la-footer p {
  margin: 0;
}
.la-footer ul {
  column-gap: 1.5rem;
  row-gap: 0.5rem;
}
.la-footer a {
  color: var(--la-on-ink-muted);
  text-decoration: underline;
  text-underline-offset: 2px;
}
.la-footer a:hover {
  color: var(--la-on-ink);
}

.la-header a:focus-visible,
.la-header summary:focus-visible,
.la-footer a:focus-visible,
.la-preview a:focus-visible {
  outline: var(--la-focus);
  outline-offset: 2px;
}

/* The language switch: the last entry of the navigation, set apart from the links to pages. */
.la-nav .la-lang {
  padding-left: 1.5rem;
  border-left: 1px solid var(--la-on-ink-muted);
}

/* The menu for a phone (a <details> with the links in groups) and the row of links for a wide screen are two
   navigations in the HTML; CSS shows one. display: none keeps the hidden one away from assistive technology. */
.la-menu {
  display: none;
}
@media (max-width: 40rem) {
  .la-header {
    position: relative;
  }
  .la-header__inner {
    flex-wrap: nowrap;
  }
  .la-nav--bar {
    display: none;
  }
  .la-menu {
    display: block;
  }
  .la-menu summary {
    display: flex;
    align-items: center;
    min-height: 2.75rem;
    margin-right: -0.4rem; /* room for the focus ring at the edge of the screen */
    padding: 0.5rem 0.4rem;
    color: var(--la-on-ink);
    font: 600 0.9rem/1.2 var(--la-font);
    list-style: none;
    cursor: pointer;
  }
  .la-menu summary::-webkit-details-marker {
    display: none;
  }
  /* The burger and its cross are drawn with gradients: no text for a screen reader to read. */
  .la-menu summary::after {
    content: "";
    flex: none;
    width: 1.125rem;
    height: 0.875rem;
    margin-left: 0.6rem;
    background:
      linear-gradient(currentColor, currentColor) 0 0 / 100% 2px no-repeat,
      linear-gradient(currentColor, currentColor) 0 6px / 100% 2px no-repeat,
      linear-gradient(currentColor, currentColor) 0 12px / 100% 2px no-repeat;
  }
  .la-menu[open] summary::after {
    background:
      linear-gradient(45deg, transparent calc(50% - 1px), currentColor calc(50% - 1px), currentColor calc(50% + 1px), transparent calc(50% + 1px)),
      linear-gradient(-45deg, transparent calc(50% - 1px), currentColor calc(50% - 1px), currentColor calc(50% + 1px), transparent calc(50% + 1px));
  }
  .la-nav--menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 100;
    box-sizing: border-box;
    max-height: calc(100vh - 4rem);
    max-height: calc(100dvh - 4rem);
    padding: 0.25rem var(--la-gutter) 1rem;
    overflow-y: auto;
    background: var(--la-ink);
    border-top: 1px solid var(--la-ink-soft);
    box-shadow: 0 12px 24px rgb(0 0 0 / 0.35);
  }
  .la-menu__title {
    margin: 0.75rem 0 0.1rem;
    color: #94a3b8; /* slate-400: 6.9:1 on --la-ink */
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
  }
  .la-nav--menu ul {
    flex-direction: column;
    row-gap: 0;
  }
  .la-nav--menu a {
    padding: 0.55rem 0;
    font-size: 1rem;
  }
  .la-menu__lang {
    margin-top: 0.75rem;
    padding-top: 0.25rem;
    border-top: 1px solid var(--la-ink-soft);
  }
  .la-nav--menu .la-lang {
    padding-left: 0;
    border-left: 0;
  }
}