/* Shared 9order navigation: readable desktop links and a full-screen small-screen menu.
   Loaded after each page's legacy styles to keep one source of truth. */
/* The small LAB/LEARN wordmark also needs to remain legible. */
.library-nav-shell .library-brand small,
.nav-shell .brand small { font-size: .6875rem; color: #141517; }
.library-nav-shell .library-links,
.nav-shell .nav-links {
  color: #141517;
  font-size: .8125rem; /* 13px at the browser default, never the old 9px */
  font-weight: 600;
  gap: clamp(12px, 1.35vw, 22px);
  white-space: nowrap;
}
.library-nav-shell .library-links > a,
.nav-shell .nav-links > a {
  color: #141517;
  text-underline-offset: 5px;
}
.library-nav-shell .library-links > a:hover,
.nav-shell .nav-links > a:hover {
  color: #141517;
  text-decoration: underline;
}
.site-nav-panel > a[aria-current="page"] {
  font-weight: 700;
  box-shadow: inset 0 -2px 0 var(--accent, #ff5b35);
}
.site-nav-toggle,
.site-nav-extra { display: none; }
.site-nav-toggle:focus-visible,
.site-nav-panel a:focus-visible {
  outline: 3px solid var(--accent, #ff5b35);
  outline-offset: 3px;
}

@media (max-width: 1200px) {
  .library-nav-shell,
  .nav-shell {
    --site-header-height: 64px;
    z-index: 300;
    background: var(--paper, #f2eee6);
    /* A backdrop-filter makes fixed descendants relative to the header. */
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }
  .library-nav-shell .library-nav,
  .nav-shell .nav {
    min-height: var(--site-header-height);
    height: var(--site-header-height);
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 12px;
    padding-top: 0;
  }
  .library-nav-shell .nav-actions,
  .nav-shell .nav-actions {
    display: none !important;
  }
  .site-nav-toggle {
    display: inline-flex;
    grid-column: 2;
    grid-row: 1;
    align-items: center;
    justify-content: center;
    gap: 11px;
    min-height: 44px;
    padding: 0 15px;
    border: 1.5px solid #141517;
    border-radius: 0;
    background: var(--paper-2, #fbf9f4);
    color: #141517;
    cursor: pointer;
    font: 600 14px/1 var(--mono, ui-monospace, monospace);
    letter-spacing: .03em;
  }
  .site-nav-toggle:hover {
    background: var(--accent-soft, #ffe4da);
  }
  .site-nav-lines { display: grid; gap: 5px; width: 18px; }
  .site-nav-lines span {
    display: block;
    width: 18px;
    height: 2px;
    background: currentColor;
    transition: transform .18s ease;
  }
  [data-site-nav][data-open] .site-nav-lines span:first-child {
    transform: translateY(3.5px) rotate(45deg);
  }
  [data-site-nav][data-open] .site-nav-lines span:last-child {
    transform: translateY(-3.5px) rotate(-45deg);
  }
  .library-nav-shell .library-links,
  .nav-shell .nav-links {
    position: fixed;
    inset: var(--site-header-height) 0 0;
    z-index: 301;
    display: none;
    width: 100%;
    max-width: none;
    height: calc(100vh - var(--site-header-height));
    height: calc(100dvh - var(--site-header-height));
    min-height: 0;
    margin: 0;
    padding: clamp(18px, 4vw, 40px) max(20px, calc((100vw - 900px) / 2)) 48px;
    border-top: 1px solid #141517;
    background: var(--paper, #f2eee6);
    color: #141517;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    overflow-x: hidden;
    overflow-y: auto;
    overscroll-behavior: contain;
    -webkit-overflow-scrolling: touch;
    white-space: normal;
  }
  .library-nav-shell[data-open] .library-links,
  .nav-shell[data-open] .nav-links {
    display: flex;
  }
  .site-nav-panel { counter-reset: site-nav-item; }
  .library-nav-shell .site-nav-panel > a,
  .nav-shell .site-nav-panel > a {
    counter-increment: site-nav-item;
    display: grid;
    grid-template-columns: 30px minmax(0, 1fr) 24px;
    align-items: center;
    gap: 16px;
    min-height: 62px;
    padding: 10px 0;
    border-bottom: 1px solid rgba(20, 21, 23, .24);
    color: #141517;
    font: 600 clamp(21px, 3.8vw, 28px)/1.2 var(--display, system-ui, sans-serif);
    letter-spacing: -.035em;
    text-transform: none;
    text-decoration: none;
    box-shadow: none;
  }
  .site-nav-panel > a::before {
    content: counter(site-nav-item, decimal-leading-zero);
    color: #55504a;
    font: 600 12px/1 var(--mono, ui-monospace, monospace);
    letter-spacing: 0;
  }
  .site-nav-panel > a::after {
    content: "↗";
    text-align: right;
    color: #55504a;
    font: 600 17px/1 var(--mono, ui-monospace, monospace);
  }
  .site-nav-panel > a[aria-current="page"] {
    color: #141517;
    border-bottom: 2px solid var(--accent, #ff5b35);
  }
  .site-nav-panel > a:hover {
    background: var(--accent-soft, #ffe4da);
  }
  .site-nav-panel .site-nav-extra {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
    padding-top: 24px;
    margin-top: 10px;
  }
  .site-nav-extra-label {
    flex: 0 0 100%;
    padding-bottom: 2px;
    color: #55504a;
    font: 600 12px/1.4 var(--mono, ui-monospace, monospace);
    text-transform: uppercase;
    letter-spacing: .07em;
  }
  .site-nav-panel .site-nav-extra a {
    display: inline-flex;
    min-height: 44px;
    align-items: center;
    padding: 10px 14px;
    border: 1px solid #141517;
    color: #141517;
    background: var(--paper-2, #fbf9f4);
    font: 600 13px/1.35 var(--mono, ui-monospace, monospace);
    text-transform: none;
    letter-spacing: 0;
    text-decoration: none;
  }
  .site-nav-panel .site-nav-extra a:hover {
    background: var(--accent-soft, #ffe4da);
  }
  html.site-nav-open,
  html.site-nav-open body {
    overflow: hidden;
    overscroll-behavior: none;
  }
}
@media (max-width: 620px) {
  .library-nav-shell .library-nav,
  .nav-shell .nav {
    width: min(calc(100% - 32px), var(--max, 1180px));
  }
}
@media (prefers-reduced-motion: reduce) {
  .site-nav-lines span { transition: none; }
}
@media print {
  .site-nav-toggle { display: none !important; }
}