/* Page frame: header, main area widths, footer and the page-level grids. */
.shell {
  width: min(var(--shell-width), 100% - 2 * var(--space-5));
  margin-inline: auto;
}

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

.nowrap {
  white-space: nowrap;
}

.skip-link {
  position: absolute;
  left: var(--space-4);
  top: -5rem;
  z-index: 100;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--color-ink);
  color: var(--color-bg);
  font-weight: 600;
  transition: top var(--duration-base) var(--ease-out);
}

.skip-link:focus {
  top: var(--space-4);
  color: var(--color-bg);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--color-line);
  background: color-mix(in srgb, var(--color-surface) 88%, transparent);
  backdrop-filter: saturate(1.4) blur(10px);
  view-transition-name: site-header;
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--space-3) var(--space-6);
  min-height: 4.25rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-ink);
  font-weight: 750;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand:hover {
  color: var(--color-ink);
}

.brand__mark {
  display: block;
  /* rem instead of the 32 px attribute, so the mark scales with the interface on large screens. */
  width: 2rem;
  height: 2rem;
  border-radius: 8px;
  transition: transform var(--duration-slow) var(--ease-spring);
}

.brand:hover .brand__mark {
  transform: rotate(-8deg) scale(1.06);
}

.site-menu {
  display: flex;
  flex: 1;
}

.site-menu__inner {
  display: flex;
  flex: 1;
  align-items: center;
  gap: var(--space-3) var(--space-6);
}

.site-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav a {
  position: relative;
  display: block;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  color: var(--color-muted);
  font-weight: 550;
  text-decoration: none;
  transition:
    color var(--duration-fast) ease,
    background-color var(--duration-fast) ease;
}

/* The underline grows from the centre on hover and stays for the current page. */
.site-nav a::after {
  content: '';
  position: absolute;
  left: var(--space-3);
  right: var(--space-3);
  bottom: 0.3rem;
  height: 2px;
  border-radius: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transition: transform var(--duration-base) var(--ease-out);
}

.site-nav a:hover,
.site-nav a[aria-current='page'] {
  color: var(--color-ink);
}

.site-nav a:hover::after,
.site-nav a[aria-current='page']::after {
  transform: scaleX(1);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-left: auto;
}

.site-header__actions form {
  margin: 0;
}

.menu-toggle {
  display: none;
}

/* Main area */
.page {
  flex: 1;
  width: min(var(--shell-width), 100% - 2 * var(--space-5));
  margin-inline: auto;
  padding-block: var(--space-7) var(--space-8);
  view-transition-name: page;
}

.page--text {
  width: min(var(--text-width), 100% - 2 * var(--space-5));
}

.page--narrow {
  width: min(32rem, 100% - 2 * var(--space-5));
}

.page--auth {
  width: min(60rem, 100% - 2 * var(--space-5));
}

.section {
  margin-top: var(--space-9);
}

.section__title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-5);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-line);
  background: var(--color-surface);
  color: var(--color-muted);
  font-size: var(--text-sm);
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-3) var(--space-6);
  padding-block: var(--space-5);
}

.site-footer__meta {
  margin: 0 auto 0 0;
}

.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-5);
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-footer__links a {
  color: var(--color-muted);
}

.site-footer__links a:hover {
  color: var(--color-ink);
}

/* Home */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: var(--space-7);
  align-items: center;
  min-height: min(38rem, 72vh);
}

.hero__title {
  font-size: var(--text-display);
  line-height: 0.98;
  letter-spacing: -0.045em;
  margin-bottom: var(--space-5);
  /* At display size automatic hyphenation splits short words; the copy sets break points with ­ where needed. */
  hyphens: manual;
}

.hero__lead {
  max-width: 34rem;
  margin-bottom: var(--space-6);
  color: var(--color-muted);
  font-size: var(--text-md);
}

.feature-grid {
  border-top: 1px solid var(--color-line-strong);
}

/* Security page */
.control-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-7) var(--space-8);
}

/* Sign-in pages: form and check chain side by side */
.auth-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 17rem;
  gap: var(--space-6);
  align-items: start;
}

/* Account */
.account-layout {
  display: grid;
  grid-template-columns: 17.5rem minmax(0, 1fr);
  gap: var(--space-6);
  align-items: start;
  margin-top: var(--space-6);
}

.account-summary {
  position: sticky;
  top: calc(4.25rem + var(--space-5));
}

.account-sections {
  display: grid;
  gap: var(--space-5);
}

.account-sections .form {
  max-width: 36rem;
}

/* Admin */
.admin-layout {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-5);
  margin-top: var(--space-6);
}

.admin-layout__wide {
  grid-column: 1 / -1;
}

@media (max-width: 60rem) {
  .hero,
  .control-grid,
  .account-layout,
  .admin-layout,
  .auth-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero {
    min-height: 0;
  }

  .account-summary {
    position: static;
  }
}

/* Phones and tablets: the menu folds behind a button. Without JavaScript it simply stays open. */
@media (max-width: 60rem) {
  /* No row gap: the folded menu is an empty second row and would push logo and button off centre. */
  .site-header__inner {
    flex-wrap: wrap;
    gap: 0 var(--space-3);
    min-height: 3.75rem;
  }

  /* The first row keeps its own height, so logo and toggle stay put when the menu opens below them. */
  .site-header__inner > .brand {
    min-height: 3.75rem;
  }

  .js .menu-toggle {
    display: inline-grid;
    place-items: center;
    width: 2.75rem;
    height: 2.75rem;
    margin-left: auto;
    border: 1px solid var(--color-line);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    color: var(--color-ink);
    cursor: pointer;
  }

  .menu-toggle__bars,
  .menu-toggle__bars::before,
  .menu-toggle__bars::after {
    display: block;
    width: 1.1rem;
    height: 2px;
    border-radius: 2px;
    background: currentColor;
    transition:
      transform var(--duration-base) var(--ease-out),
      opacity var(--duration-fast) ease;
  }

  .menu-toggle__bars {
    position: relative;
  }

  .menu-toggle__bars::before,
  .menu-toggle__bars::after {
    content: '';
    position: absolute;
    left: 0;
  }

  .menu-toggle__bars::before {
    transform: translateY(-6px);
  }

  .menu-toggle__bars::after {
    transform: translateY(6px);
  }

  .menu-toggle[aria-expanded='true'] .menu-toggle__bars {
    background: transparent;
  }

  .menu-toggle[aria-expanded='true'] .menu-toggle__bars::before {
    transform: rotate(45deg);
  }

  .menu-toggle[aria-expanded='true'] .menu-toggle__bars::after {
    transform: rotate(-45deg);
  }

  .site-menu {
    flex-basis: 100%;
    padding-bottom: var(--space-4);
  }

  .site-menu__inner {
    flex-direction: column;
    align-items: stretch;
  }

  .js .site-menu {
    display: grid;
    grid-template-rows: 0fr;
    padding-bottom: 0;
    visibility: hidden;
    transition:
      grid-template-rows var(--duration-slow) var(--ease-out),
      padding var(--duration-slow) var(--ease-out),
      visibility 0s linear var(--duration-slow);
  }

  /* The padding gives focus rings room inside the clipped area; the negative margin keeps the alignment. */
  .js .site-menu > * {
    min-height: 0;
    margin-inline: -6px;
    padding-inline: 6px;
    overflow: hidden;
  }

  /* Inside the clipped content, so a folded menu still takes no space. */
  .js .site-menu__inner > :first-child {
    margin-top: 6px;
  }

  .js .site-menu__inner > :last-child {
    margin-bottom: 6px;
  }

  .js .site-menu.is-open {
    grid-template-rows: 1fr;
    padding-top: var(--space-2);
    padding-bottom: var(--space-4);
    visibility: visible;
    transition-delay: 0s;
  }

  .site-nav ul {
    flex-direction: column;
  }

  .site-header__actions {
    margin-left: 0;
  }

  .page {
    padding-block: var(--space-6) var(--space-7);
  }

  .section {
    margin-top: var(--space-8);
  }
}