// Shell: the sticky top bar, the signed-in sidebar, the page column and the footer. From 900px
// the sidebar is always there, and a repo's tabs take it over. Below 900px the sidebar moves
// into a menu in the top bar, and the repo tabs become a horizontal strip.

// Icons: strokes use currentColor, so they follow the text colour in both themes.
.ico {
  flex: none;
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

// Top bar

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 12px;
  box-sizing: border-box;
  height: var(--topbar-h);
  min-width: 0;
  padding: 0 16px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: none;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  text-decoration: none;

  &:hover {
    text-decoration: none;
  }
}

.wordmark-mark {
  width: 20px;
  height: 20px;
  color: var(--accent);
}

.topbar .crumbs {
  display: flex;
  align-items: center;
  flex: 0 1 auto;
  min-width: 0;
  overflow: hidden;
  font-size: 14px;
  color: var(--muted);
  white-space: nowrap;

  &::before {
    content: "/";
    margin-right: 10px;
    color: var(--border-strong);
  }

  ol {
    flex-wrap: nowrap;
  }
}

.top-search {
  position: relative;
  flex: 0 1 340px;
  min-width: 0;
  margin: 0 0 0 auto;

  input {
    box-sizing: border-box;
    width: 100%;
    height: 36px;
    min-width: 0;
    margin: 0;
    padding: 0 12px 0 36px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--surface);
    color: var(--text);
    font: inherit;
    font-size: 14px;

    &::placeholder {
      color: var(--muted);
    }

    &:focus {
      outline: none;
      border-color: var(--accent);
      box-shadow: 0 0 0 3px var(--accent-soft);
    }
  }
}

.top-search-icon {
  position: absolute;
  top: 10px;
  left: 11px;
  width: 16px;
  height: 16px;
  color: var(--muted);
  pointer-events: none;
}

.topbar .icon-btn {
  position: relative;
  display: grid;
  place-items: center;
  flex: none;
  box-sizing: border-box;
  width: 36px;
  height: 36px;
  margin: 0;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text-2);
  font: inherit;
  list-style: none;
  cursor: pointer;

  &:hover {
    background: var(--surface-2);
    text-decoration: none;
  }

  &::-webkit-details-marker {
    display: none;
  }
}

.theme-form {
  display: flex;
  flex: none;
  margin: 0;
}

.topbar .bell {
  color: var(--text-2);
}

.topbar .bell-count {
  position: absolute;
  top: -6px;
  right: -6px;
  min-width: 1.2rem;
  padding: 0 0.3rem;
  box-shadow: 0 0 0 2px var(--bg);
  font-size: 0.6875rem;
  line-height: 1.2rem;
}

// The shared button keeps its natural width in columns; in the top bar it sits on the centre line.
.topbar .button {
  align-self: center;
  flex: none;
}

.topbar-link {
  flex: none;
  color: var(--text-2);
  font-size: 14.5px;
  font-weight: 500;
  text-decoration: none;

  &:hover {
    color: var(--text);
    text-decoration: none;
  }
}

// The avatar menu: the avatar is the summary; the menu list keeps its links from main.scss.
.topbar .menu {
  flex: none;

  summary {
    display: grid;
    place-items: center;
    width: 36px;
    height: 36px;
    padding: 0;
    border: 0;
    border-radius: 50%;
  }

  summary img {
    display: block;
    width: 28px;
    height: 28px;
  }

  &[open] summary {
    box-shadow: 0 0 0 2px var(--accent-soft);
  }
}

.topbar .menu-list {
  top: calc(100% + 8px);
}

// Phone menu: the sidebar in a panel under the top bar. Hidden from 900px.

.nav-toggle {
  flex: none;
}

.nav-panel {
  position: absolute;
  top: 100%;
  left: 12px;
  z-index: 30;
  box-sizing: border-box;
  width: 280px;
  max-width: calc(100vw - 24px);
  max-height: calc(100vh - var(--topbar-h));
  padding: 12px;
  overflow-y: auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

// Sidebar

.shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  min-height: calc(100vh - var(--topbar-h));
}

.shell-sidebar {
  display: none;
}

.side-links {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.side-link {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 36px;
  padding: 0 12px;
  border-radius: var(--radius);
  color: var(--text-2);
  font-size: 14.5px;
  font-weight: 500;
  white-space: nowrap;
  text-decoration: none;

  &:hover {
    background: var(--surface-2);
    text-decoration: none;
  }

  .ico {
    color: var(--muted);
  }

  .count {
    margin-left: auto;
    font-size: 12.5px;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
  }

  &.on {
    background: var(--accent-soft);
    color: var(--accent-ink);
    font-weight: 600;

    .ico,
    .count {
      color: var(--accent-ink);
    }
  }
}

.side-group {
  margin-top: 24px;
}

.side-h {
  margin: 0 12px 8px;
  font-size: 12.5px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--muted);
}

.side-empty {
  margin: 0 12px;
  font-size: 13px;
  color: var(--muted);
}

.side-repos {
  display: flex;
  flex-direction: column;
  gap: 2px;

  a {
    display: flex;
    align-items: center;
    min-height: 32px;
    padding: 0 12px;
    overflow: hidden;
    border-radius: var(--radius);
    font-family: var(--mono);
    font-size: 13.5px;
    color: var(--text-2);
    white-space: nowrap;
    text-decoration: none;

    &:hover {
      background: var(--surface-2);
      text-decoration: none;
    }
  }
}

// Page column and footer

.shell > main {
  box-sizing: border-box;
  width: 100%;
  min-width: 0;
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  box-sizing: border-box;
  padding: 14px 16px 20px;
  font-size: 12.5px;
  color: var(--muted);
  border-top: 1px solid var(--border);
}

// Wide screens: the sidebar sits beside the page, and a repo's tabs replace its links.

@media (max-width: 699px) {
  .topbar .crumbs {
    display: none;
  }

  .top-search {
    flex: 1 1 0;
  }
}

// Narrow phones: the search field no longer fits beside the other top bar items, so it becomes an
// icon that opens the public repository search on the Explore page (the same search, no JS).
.topbar .top-search-link {
  display: none;
}

@media (max-width: 639px) {
  .top-search {
    display: none;
  }

  .topbar .top-search-link {
    display: grid;
    margin-left: auto;
  }
}

@media (min-width: 700px) {
  .shell > main {
    padding: 28px 28px 48px;
  }

  .site-footer {
    padding: 14px 28px 20px;
  }
}

@media (min-width: 900px) {
  .nav-toggle {
    display: none;
  }

  .shell:has(> .shell-sidebar) {
    grid-template-columns: var(--sidebar-w) minmax(0, 1fr);
  }

  .shell-sidebar {
    position: sticky;
    top: var(--topbar-h);
    align-self: start;
    display: block;
    box-sizing: border-box;
    height: calc(100vh - var(--topbar-h));
    min-width: 0;
    padding: 16px 12px 24px;
    overflow-y: auto;
    background: var(--surface);
    border-right: 1px solid var(--border);
  }

  // A repo page: its tabs become the sidebar, fixed under the top bar, and the global links go.
  .shell:has(.repo-tabs) .shell-sidebar .side-links,
  .shell:has(.repo-tabs) .shell-sidebar .side-group {
    display: none;
  }

  .shell:has(> .shell-sidebar) .repo-tabs {
    position: fixed;
    top: var(--topbar-h);
    bottom: 0;
    left: 0;
    z-index: 5;
    box-sizing: border-box;
    width: var(--sidebar-w);
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    margin: 0;
    padding: 16px 12px 24px;
    overflow-x: hidden;
    overflow-y: auto;
    background: var(--surface);
    border-right: 1px solid var(--border);
    border-bottom: 0;
  }

  .shell:has(> .shell-sidebar) .repo-tabs .tab {
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 36px;
    padding: 0 12px;
    border-radius: var(--radius);
    box-shadow: none;
    color: var(--text-2);
    font-size: 14.5px;
    font-weight: 500;

    &:hover {
      background: var(--surface-2);
      color: var(--text);
    }

    &.active {
      background: var(--accent-soft);
      color: var(--accent-ink);
      font-weight: 600;
      box-shadow: none;
    }
  }

  .shell:has(> .shell-sidebar) .repo-tabs .tab-count {
    margin-left: auto;
    padding: 0;
    background: none;
    font-size: 12.5px;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
  }
}

// Soft navigation: a thin progress line along the top while a page is being fetched in place
// (nav.js sets aria-busy on <html>). Decorative; the page stays usable underneath.
html[aria-busy="true"] body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 1000;
  background: var(--accent);
  transform-origin: left center;
  pointer-events: none;
  animation: soft-nav-progress 1.1s ease-in-out infinite;
}

@keyframes soft-nav-progress {
  0% { transform: scaleX(0); }
  50% { transform: scaleX(0.7); }
  100% { transform: scaleX(1); opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html[aria-busy="true"] body::before {
    animation: none;
    transform: scaleX(1);
    opacity: 0.45;
  }
}