/* === Reading progress bar + back-to-top + section indicator === */

/* nav-scroll.css — owned by Agent A (Tier 1).
   Reading-progress hairline, back-to-top pill.
   Section indicator styles live in layout.css (Tier 0) and are not duplicated here. */

/* ── Reading progress hairline ─────────────────────────────────────────────── */

.nav-reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 100;
  pointer-events: none;
  will-change: transform;
  transition: transform 80ms linear;
}

@media (prefers-reduced-motion: reduce) {
  .nav-reading-progress { transition: none; }
}

/* ── Back-to-top pill ──────────────────────────────────────────────────────── */

.nav-back-to-top {
  position: fixed;
  right: max(var(--s-4), env(safe-area-inset-right, 0));
  bottom: max(var(--s-5), env(safe-area-inset-bottom, 0));
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--surface-0);
  color: var(--text);
  border: 1px solid var(--border-strong);
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 4px 16px var(--shadow);
  opacity: 0;
  transform: translateY(8px);
  transition: opacity var(--dur-med) var(--ease), transform var(--dur-med) var(--ease), background var(--dur) var(--ease);
  z-index: 50;
}

.nav-back-to-top[data-visible="true"] {
  opacity: 1;
  transform: translateY(0);
}

.nav-back-to-top:hover {
  background: var(--surface-1);
}

.nav-back-to-top:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  .nav-back-to-top { transition: none; }
}

/* === Breadcrumbs + adjacent-section nav === */

/* =============================================================================
   Breadcrumbs  (Agent B — nav/crumbs)
   Uses CSS tokens only — no hardcoded colors. Works across light/dark/parchment.
   ============================================================================= */

/* Hide the nav entirely when the crumb list is empty (home page). */
.nav-crumbs:not(:has(li)) {
  display: none;
}

.nav-crumbs {
  margin: 0 0 var(--s-4);
  font-size: 13px;
  color: var(--text-faint);
}
.nav-crumbs ol {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
}
.nav-crumbs li {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  text-transform: lowercase;
}
.nav-crumbs li:not(:last-child)::after {
  content: "\203a"; /* › */
  margin: 0 8px;
  color: var(--text-faint);
}
.nav-crumbs a {
  color: var(--text-muted);
  text-decoration: none;
  padding: 2px 0;
  transition: color var(--dur) var(--ease);
}
.nav-crumbs a:hover {
  color: var(--text);
  text-decoration: underline;
}
.nav-crumbs [aria-current="page"] {
  color: var(--text-muted);
  max-width: 40ch;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
@media (max-width: 640px) {
  .nav-crumbs [aria-current="page"] {
    max-width: 25ch;
  }
}

/* =============================================================================
   Adjacent-section nav  (Agent B — nav/crumbs)
   Only appears on top-level section pages (about, gallery, posts, resume, portfolio).
   ============================================================================= */

.nav-adjacent {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--s-4);
  margin: var(--s-7) 0 var(--s-5);
  padding: var(--s-4) 0;
  border-top: 1px solid var(--border);
}
.nav-adjacent-prev,
.nav-adjacent-next {
  display: flex;
  flex-direction: column;
  gap: var(--s-1);
  padding: var(--s-3) var(--s-4);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  text-decoration: none;
  color: var(--text);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.nav-adjacent-prev:hover,
.nav-adjacent-next:hover {
  border-color: var(--border-strong);
  background: var(--surface-1);
}
.nav-adjacent-next {
  text-align: right;
}
.nav-adjacent-label {
  font-size: var(--fs-caption);
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: var(--ls-label);
}
.nav-adjacent-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 16px;
  color: var(--text);
}
@media (max-width: 640px) {
  .nav-adjacent {
    grid-template-columns: 1fr;
    gap: var(--s-2);
  }
  .nav-adjacent-next {
    text-align: left;
  }
}

/* Respect prefers-reduced-motion — disable transitions. */
@media (prefers-reduced-motion: reduce) {
  .nav-crumbs a,
  .nav-adjacent-prev,
  .nav-adjacent-next {
    transition: none;
  }
}

/* === Sticky in-page TOC sidebar === */

/* Sticky in-page TOC — Agent C.
   Applies only at ≥1080px viewports. Below that the TOC remains inline
   (components.css .toc rules handle appearance; nothing here changes it).

   Uses :has() so we only activate the grid when a .toc is actually in the
   DOM. Safari ≤15.3 doesn't support :has(); the @supports guard means those
   browsers silently fall back to the existing inline TOC. Safari 15.4+
   (March 2022) and all current Chromium / Firefox get the sidebar. */

@supports (selector(:has(*))) {
  @media (min-width: 1080px) {
    /* Two-column layout: article on the left, TOC pinned on the right.
       Only activates when the page actually has a .toc direct child of main. */
    body:has(main.content > .toc) main.content {
      max-width: 1080px;
      display: grid;
      grid-template-columns: minmax(0, 720px) var(--sidebar-w);
      column-gap: var(--s-7);
      align-items: start;
    }

    /* Row layout (when a .toc is present):
         row 1: nav-crumbs spans both columns
         row 2: article (col 1) + toc (col 2, sticky)
         row 3+: nav-adjacent / back-to-top span both columns */
    body:has(main.content > .toc) main.content > .nav-crumbs {
      grid-column: 1 / -1;
      grid-row: 1;
    }

    /* TOC: second column, second row. position: sticky pins it as
       the article scrolls past. Strip the card appearance from
       components.css so it reads as a lightweight sidebar element. */
    body:has(main.content > .toc) main.content > .toc {
      position: sticky;
      top: calc(var(--topbar-h) + var(--s-4));
      grid-column: 2;
      grid-row: 2;
      margin: 0;
      background: transparent;
      border: none;
      padding: 0;
      max-height: calc(100vh - var(--topbar-h) - var(--s-5));
      overflow-y: auto;
    }

    /* Article: first column, second row. */
    body:has(main.content > .toc) main.content > article {
      grid-column: 1;
      grid-row: 2;
    }

    /* Adjacent / back-to-top span the full width below the article. */
    body:has(main.content > .toc) main.content > .nav-adjacent,
    body:has(main.content > .toc) main.content > .post-adjacent,
    body:has(main.content > .toc) main.content > .post-nav,
    body:has(main.content > .toc) main.content > #nav-back-to-top {
      grid-column: 1 / -1;
    }
  }
}

/* Active-section highlight — works at all viewport widths (the JS sets it
   regardless; only the sticky layout is viewport-gated). */
.toc-list .toc-item.active > a {
  color: var(--accent);
  font-weight: 500;
}

/* === Mobile swipe navigation (View Transitions + edge indicator) === */

/* ============================================================
   Mobile swipe navigation — View Transitions + edge indicator
   ============================================================ */

/* Enable cross-document view transitions for same-origin navigations.
   This pairs with the JS calling document.startViewTransition() on swipe. */
@view-transition {
  navigation: auto;
}

/* --- Slide keyframes ---
   Swipe-left (forward): old page exits left, new page enters from right.
   Swipe-right (backward): old page exits right, new page enters from left. */
@keyframes swipe-out-left {
  from { transform: translateX(0);    opacity: 1; }
  to   { transform: translateX(-30%); opacity: 0; }
}
@keyframes swipe-in-right {
  from { transform: translateX(100%); opacity: 1; }
  to   { transform: translateX(0);   opacity: 1; }
}
@keyframes swipe-out-right {
  from { transform: translateX(0);   opacity: 1; }
  to   { transform: translateX(30%); opacity: 0; }
}
@keyframes swipe-in-left {
  from { transform: translateX(-100%); opacity: 1; }
  to   { transform: translateX(0);    opacity: 1; }
}

/* Default direction: swipe-left (forward). Applied to the outgoing document. */
::view-transition-old(root) {
  animation: 220ms cubic-bezier(0.22, 0.72, 0.18, 1) both swipe-out-left;
}
/* Applied to the incoming document. */
::view-transition-new(root) {
  animation: 220ms cubic-bezier(0.22, 0.72, 0.18, 1) both swipe-in-right;
}

/* Swipe-right direction: old exits right, new enters from left. */
[data-swipe-direction="right"] ::view-transition-old(root) {
  animation-name: swipe-out-right;
}
[data-swipe-direction="right"] ::view-transition-new(root) {
  animation-name: swipe-in-left;
}

/* Honour prefers-reduced-motion: skip animation, still allow swipe-to-navigate. */
@media (prefers-reduced-motion: reduce) {
  ::view-transition-old(root),
  ::view-transition-new(root) {
    animation: none;
  }
}

/* --- Edge indicator ---
   While the user is actively dragging horizontally, a thin accent bar peeks
   at the appropriate edge of the viewport to hint "you can swipe here."
   The CSS custom property --swipe-progress is set by the JS in [-1, 1]:
     negative = swiping left  → hint on the right edge
     positive = swiping right → hint on the left edge
   We render two pseudo-elements and show only the relevant one. */

/* Right-edge bar: shown when swiping left (--swipe-progress < 0) */
html.swipe-tracking::after {
  content: "";
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: 3px;
  background: var(--accent);
  z-index: 9999;
  pointer-events: none;
  /* opacity ramps from 0 to 1 as the user drags leftward */
  opacity: clamp(0, calc(var(--swipe-progress, 0) * -10), 1);
  transition: opacity 80ms linear;
}

/* Left-edge bar: shown when swiping right (--swipe-progress > 0) */
html.swipe-tracking::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 3px;
  background: var(--accent);
  z-index: 9999;
  pointer-events: none;
  /* opacity ramps from 0 to 1 as the user drags rightward */
  opacity: clamp(0, calc(var(--swipe-progress, 0) * 10), 1);
  transition: opacity 80ms linear;
}

/* Don't animate the indicator if the user prefers reduced motion */
@media (prefers-reduced-motion: reduce) {
  html.swipe-tracking::before,
  html.swipe-tracking::after {
    transition: none;
  }
}

/* === Command palette (Cmd+K) === */

/* Command palette — nav-cmdk.css
   All colors via design tokens (tokens.css + themes.css). No hardcoded values. */

/* ------------------------------------------------------------------ */
/* Backdrop                                                             */
/* ------------------------------------------------------------------ */

.cmdk-backdrop {
  position: fixed;
  inset: 0;
  background: color-mix(in oklab, var(--text) 45%, transparent);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 1000;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 12vh var(--s-4) var(--s-4);
  animation: cmdk-fade-in 160ms ease forwards;
}

/* The [hidden] attribute hides the palette; animation runs on reveal. */
.cmdk-backdrop[hidden] {
  display: none;
}

@keyframes cmdk-fade-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes cmdk-slide-in {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ------------------------------------------------------------------ */
/* Panel                                                                */
/* ------------------------------------------------------------------ */

.cmdk-panel {
  width: 100%;
  max-width: 560px;
  background: var(--surface-0);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: 0 24px 60px color-mix(in oklab, var(--text) 30%, transparent);
  overflow: hidden;
  animation: cmdk-slide-in 200ms cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

/* ------------------------------------------------------------------ */
/* Input row                                                            */
/* ------------------------------------------------------------------ */

.cmdk-input-row {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  padding: var(--s-3) var(--s-4);
  border-bottom: 1px solid var(--border);
}

.cmdk-glyph {
  color: var(--text-muted);
  font-size: 18px;
  line-height: 1;
  flex-shrink: 0;
}

.cmdk-input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  color: var(--text);
  font-family: inherit;
  font-size: 16px;
  padding: 4px 0;
  min-width: 0;
}

.cmdk-input::placeholder {
  color: var(--text-faint);
}

.cmdk-esc-hint {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-muted);
  background: var(--surface-2);
  padding: 3px 7px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  flex-shrink: 0;
}

/* ------------------------------------------------------------------ */
/* Results list                                                         */
/* ------------------------------------------------------------------ */

.cmdk-list {
  list-style: none;
  margin: 0;
  padding: var(--s-2) 0;
  max-height: 50vh;
  overflow-y: auto;
  scroll-behavior: smooth;
}

/* Group label (used in empty/default state when items are grouped by kind) */
.cmdk-group-label {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-faint);
  padding: var(--s-3) var(--s-4) var(--s-1);
  list-style: none;
}

/* ------------------------------------------------------------------ */
/* Individual items                                                     */
/* ------------------------------------------------------------------ */

.cmdk-item {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  padding: 9px var(--s-4);
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease);
  list-style: none;
}

.cmdk-item:hover {
  background: var(--surface-hover);
}

.cmdk-item.active {
  background: var(--accent-subtle);
}

.cmdk-item-icon {
  width: 24px;
  height: 24px;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 13px;
  flex-shrink: 0;
}

.cmdk-item.active .cmdk-item-icon {
  background: var(--accent-subtle);
  color: var(--accent);
}

.cmdk-item-text {
  flex: 1;
  min-width: 0;
}

.cmdk-item-title {
  display: block;
  font-size: 14px;
  color: var(--text);
  line-height: 1.2;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.cmdk-item-meta {
  display: block;
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 2px;
  line-height: 1.2;
}

.cmdk-item-kind {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-muted);
  flex-shrink: 0;
}

/* ------------------------------------------------------------------ */
/* Empty state                                                          */
/* ------------------------------------------------------------------ */

.cmdk-empty {
  padding: var(--s-5) var(--s-4);
  color: var(--text-muted);
  text-align: center;
  font-size: 14px;
  list-style: none;
}

/* ------------------------------------------------------------------ */
/* Footer hint bar                                                      */
/* ------------------------------------------------------------------ */

.cmdk-footer {
  border-top: 1px solid var(--border);
  padding: 8px var(--s-4);
  display: flex;
  gap: var(--s-4);
  color: var(--text-faint);
  font-size: 11px;
  background: var(--surface-1);
}

.cmdk-footer kbd {
  font-family: var(--font-mono);
  font-size: 10px;
  background: var(--surface-0);
  color: var(--text-muted);
  padding: 1px 5px;
  border-radius: 3px;
  border: 1px solid var(--border);
  margin-right: 4px;
}

/* ------------------------------------------------------------------ */
/* Highlighted match substrings                                         */
/* ------------------------------------------------------------------ */

.cmdk-item-title mark {
  background: var(--accent-subtle);
  color: var(--accent);
  padding: 0 1px;
  border-radius: 2px;
}

/* ------------------------------------------------------------------ */
/* Reduced-motion                                                       */
/* ------------------------------------------------------------------ */

@media (prefers-reduced-motion: reduce) {
  .cmdk-backdrop,
  .cmdk-panel {
    animation: none;
  }
}

/* ------------------------------------------------------------------ */
/* Mobile                                                               */
/* ------------------------------------------------------------------ */

@media (max-width: 640px) {
  .cmdk-backdrop {
    padding: 8vh var(--s-2) var(--s-2);
    align-items: flex-start;
  }

  .cmdk-panel {
    border-radius: var(--radius-lg);
  }

  .cmdk-list {
    max-height: 60vh;
  }

  .cmdk-footer {
    gap: var(--s-2);
  }
}