/* tts-reader — read-aloud player for Quarto HTML documents
 *
 * LAYOUT RULE THAT GOVERNS THIS FILE: the highlight classes are toggled on
 * individual words many times per second as the reader advances, so they must
 * NEVER change a word's box. Horizontal padding, margins, borders or a heavier
 * font-weight would reflow the line on every word and make the text visibly
 * jump while you are trying to follow it. `box-shadow` paints outside the box
 * without participating in layout, which is why it does the padding's job here.
 *
 * PALETTE: warm paper and ink with a terracotta accent, ported from the
 * author's `planning-repo`. It replaced Tailwind's yellow/sky in v2.3.0 for a
 * plain reason — those two colours are the visual signature of a generic web
 * app, and this player sits inside long-form prose. Every value below was
 * contrast-checked; the ratios are recorded where they matter.
 */

:root {
  --tts-ink: #1F1B17;         /* warm near-black — bar chrome, text on highlights */
  --tts-ink-soft: #C9BFAB;    /* bar labels: 9.5:1 on --tts-ink                   */
  --tts-accent: #D06224;      /* terracotta — the 3px rule, the play button       */
  --tts-accent-soft: #E0895A; /* current word: 6.5:1 with --tts-ink on it         */
  --tts-accent-tint: #F5E5D5; /* current sentence: 13.4:1 with --tts-ink on it    */
  --tts-rule: rgba(237, 228, 211, 0.20);
  --tts-mono: ui-monospace, "Cascadia Mono", "Segoe UI Mono", Consolas, monospace;
}

/* ---- Highlights -------------------------------------------------------
 *
 * These do NOT change between light and dark themes, and that is deliberate.
 * The obvious move — inverting to a dark background under a dark theme — is
 * exactly the bug fixed in v1.1.0: the text colour here is pinned dark, so a
 * dark background would make the highlighted words unreadable precisely while
 * they are being read. Light warm backgrounds with pinned dark text work under
 * every Quarto theme. Only the bar chrome below responds to the theme.
 */

/* Word currently being spoken. */
.tts-word.tts-word-active {
  background-color: var(--tts-accent-soft);
  color: var(--tts-ink);
  border-radius: 2px;
  box-shadow: 0 0 0 2px var(--tts-accent-soft), 0 0 6px rgba(208, 98, 36, 0.55);
}

/* Sentence (or clause) containing the current word.
 *
 * `color` is set EXPLICITLY, and that is not decoration. These highlights paint
 * a light background, but the text colour is inherited from the site theme. On
 * a dark Quarto theme (darkly, slate, dim…) the inherited colour is near-white,
 * which on a pale background gives roughly 1.1:1 contrast — the highlighted
 * text becomes invisible exactly while it is being read. Pinning a dark
 * foreground keeps the highlight legible under any theme. */
.tts-word.tts-sentence-active {
  background-color: var(--tts-accent-tint);
  color: var(--tts-ink);
  box-shadow: 0 0 0 2px var(--tts-accent-tint);
  border-radius: 2px;
}

/* …but a highlighted word inside a link must stay recognisable as a link,
 * rather than turning into ordinary body text for the moment it is read.
 *
 * Two different blues, because the two backgrounds are different: #1D4ED8 gives
 * 5.6:1 on the pale sentence tint but only 1.9:1 on the terracotta of the
 * active word, where it would vanish. #12306E holds 4.7:1 there. The underline
 * is belt and braces: it identifies the link by shape as well as by hue, and
 * `text-decoration` does not participate in layout, so it is safe under the
 * rule at the top of this file. */
a .tts-word.tts-sentence-active {
  color: #1d4ed8;
  text-decoration: underline;
}

a .tts-word.tts-word-active {
  color: #12306E;
  text-decoration: underline;
}

/* The active word must win over the sentence shading it sits inside. */
.tts-word.tts-word-active.tts-sentence-active {
  background-color: var(--tts-accent-soft);
  color: var(--tts-ink);
  box-shadow: 0 0 0 2px var(--tts-accent-soft), 0 0 6px rgba(208, 98, 36, 0.55);
}

a .tts-word.tts-word-active.tts-sentence-active {
  color: #12306E;
}

/* Fallback when the voice never reports word boundaries (typical of remote
   "Natural"/"Online" voices): shade the whole block so the reader still shows
   where it is, instead of looking frozen.
 *
 * Same dark-theme trap as above, and it matters MORE here: this is the mode
 * that users of the good remote voices actually see most of the time. */
.tts-block-active {
  background-color: var(--tts-accent-tint);
  color: var(--tts-ink);
  border-radius: 3px;
  box-shadow: 0 0 0 3px var(--tts-accent-tint);
}

.tts-block-active a {
  color: #1d4ed8;
  text-decoration: underline;
}

.tts-readable {
  cursor: pointer;
}

/* Click-to-read switched off: the pointer cursor has to go with it, or the page
   keeps advertising an affordance that no longer exists. */
body.tts-click-disabled .tts-readable {
  cursor: auto;
}

/* The reading cursor: the one block that is a Tab stop at any moment.
 *
 * `outline` and NOT a border or a background: this ring appears and disappears
 * on a block of running prose, and outlines are painted outside the box without
 * participating in layout — the same reason box-shadow does the highlighting.
 * A border here would reflow the paragraph every time the cursor moved.
 *
 * Only :focus-visible, never :focus. A plain :focus rule would draw the ring on
 * every mouse click into the text as well, which is noise: the click already
 * started the reader, and the highlight says where it is. */
.tts-readable:focus {
  outline: none;
}

.tts-readable:focus-visible {
  outline: 2px solid var(--tts-accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* Screen-reader-only live region.
 *
 * `clip-path` with a 1px box rather than `display: none` or
 * `visibility: hidden`: both of the latter remove the element from the
 * accessibility tree entirely, and a live region that is not in the tree
 * announces nothing at all — the announcements would be silently lost. */
.tts-sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---- Player bar -------------------------------------------------------
 * Fixed, not sticky: Quarto's content containers can establish scroll/overflow
 * contexts that silently neutralise `position: sticky` on a descendant. The bar
 * is appended to <body>, so `fixed` is the predictable choice.
 *
 * Opaque warm ink, NOT frosted glass. The bar carried `backdrop-filter:
 * blur(8px)` until v2.3.0; it was dropped rather than refined. Glass reads as
 * chrome borrowed from a phone OS, and the 3px terracotta rule along the top —
 * lifted from the `planning-repo` mini-player — is what actually makes the bar
 * look composed rather than bolted on.
 */
#tts-reader-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 9999;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  padding: 9px 16px;
  background: var(--tts-ink);
  color: #EDE4D3;
  border-top: 3px solid var(--tts-accent);
  box-shadow: 0 -6px 22px rgba(0, 0, 0, 0.28);
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 0.9rem;
  line-height: 1.2;

  /* Slides up on arrival. The script adds .tts-bar-in on the next animation
     frame — in the same frame there is no style recalculation between the
     element being appended and the class landing, so the transition would
     simply not run. */
  transform: translateY(100%);
  transition: transform 0.32s cubic-bezier(0.4, 0, 0.2, 1);
}

#tts-reader-bar.tts-bar-in {
  transform: translateY(0);
}

#tts-reader-bar .tts-group {
  display: flex;
  gap: 8px;
  align-items: center;
}

/* Buttons carry no fill: in an editorial layout a row of filled rectangles
   reads as a form. Exactly one element is filled — the play button — so the
   eye has one place to land. */
#tts-reader-bar button {
  padding: 5px 9px;
  border: none;
  border-radius: 2px;
  background: transparent;
  color: #EDE4D3;
  font-size: 0.95rem;
  cursor: pointer;
  opacity: 0.55;
  transition: opacity 0.15s, background 0.15s;
}

#tts-reader-bar button:hover {
  opacity: 1;
  background: rgba(237, 228, 211, 0.08);
}

#tts-reader-bar button:focus-visible {
  outline: 2px solid var(--tts-accent-soft);
  outline-offset: 2px;
  opacity: 1;
}

#tts-reader-bar #tts-play {
  background: var(--tts-accent);
  color: #FFF7EF;
  opacity: 1;
  padding: 5px 12px;
  display: flex;
  align-items: center;
  gap: 7px;
}

#tts-reader-bar #tts-play .tts-label {
  font-family: var(--tts-mono);
  font-size: 10px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

#tts-reader-bar #tts-play:hover {
  background: #B9531C;
}

/* The pulsing dot from the planning-repo mini-player: the one piece of motion
   in the bar, and only while something is actually being spoken. */
#tts-reader-bar .tts-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--tts-accent-soft);
  flex-shrink: 0;
  opacity: 0;
  transition: opacity 0.2s;
}

#tts-reader-bar.tts-bar-playing .tts-dot {
  opacity: 1;
  animation: tts-dot-pulse 1.8s ease-in-out infinite;
}

@keyframes tts-dot-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.35; transform: scale(0.65); }
}

/* Micro-labels in mono, uppercase and letter-spaced. This — not the colours —
   is what carries the editorial feel; the previous 0.8rem system-ui made the
   bar look like browser chrome. */
#tts-reader-bar label {
  font-family: var(--tts-mono);
  font-size: 9px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--tts-ink-soft);
}

#tts-reader-bar select {
  background: rgba(237, 228, 211, 0.06);
  color: #EDE4D3;
  border: 1px solid var(--tts-rule);
  border-radius: 2px;
  padding: 4px 6px;
  font-size: 0.82rem;
  cursor: pointer;
  max-width: 200px;
}

#tts-reader-bar select:focus-visible {
  outline: 2px solid var(--tts-accent-soft);
  outline-offset: 1px;
}

/* The <option> list is painted by the OS, which does not inherit the bar's
   colours — without this the dropdown opens as light text on a light popup in
   some browsers. */
#tts-reader-bar select option {
  background: var(--tts-ink);
  color: #EDE4D3;
}

/* ⚙ menu of what to read aloud */
#tts-reader-bar .tts-opts {
  position: relative;
}

#tts-reader-bar .tts-opts-panel {
  display: none;
  position: absolute;
  bottom: calc(100% + 12px);
  right: 0;
  min-width: 17rem;
  padding: 12px 14px;
  background: #17140F;
  border: 1px solid var(--tts-rule);
  border-top: 2px solid var(--tts-accent);
  border-radius: 2px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
  text-align: left;
}

#tts-reader-bar .tts-opts-open .tts-opts-panel {
  display: block;
}

#tts-reader-bar .tts-opts-title {
  margin: 0 0 8px;
  font-family: var(--tts-mono);
  font-size: 9px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--tts-ink-soft);
}

/* Second heading in the ⚙ panel, ruled off from the list above it: the
   checkboxes there say what gets SPOKEN, this one says how reading STARTS. */
#tts-reader-bar .tts-opts-title-second {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--tts-rule);
}

#tts-reader-bar .tts-opts-panel label {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 3px 0;
  font-family: inherit;
  font-size: 0.85rem;
  letter-spacing: normal;
  text-transform: none;
  color: #EDE4D3;
  cursor: pointer;
}

#tts-reader-bar .tts-opts-panel input {
  cursor: pointer;
  accent-color: var(--tts-accent);
}

#tts-reader-bar .tts-opts-note {
  margin: 8px 0 0;
  font-size: 0.72rem;
  line-height: 1.4;
  color: var(--tts-ink-soft);
  opacity: 0.75;
}

#tts-reader-bar .tts-status {
  font-family: var(--tts-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--tts-ink-soft);
  min-width: 8ch;
}

/* Keep the last lines of the document reachable above the fixed bar.
 *
 * This is only a floor. The bar wraps its controls on narrow screens, so its
 * real height varies with viewport width and font size — a fixed value would
 * cover the last line on small phones. The script measures the bar and sets an
 * inline padding-bottom that wins over this rule; this value covers the moment
 * before that runs, and the case where the script fails to load. */
body.tts-reader-active {
  padding-bottom: 76px;
}

/* Unrequested motion is the thing this media query exists to stop: a bar
   sliding in and a dot throbbing at the foot of the page are both exactly that.
   The bar still arrives and the dot still marks the playing state — they just
   do it without moving. */
@media (prefers-reduced-motion: reduce) {
  #tts-reader-bar {
    transition: none;
    transform: translateY(0);
  }
  #tts-reader-bar.tts-bar-playing .tts-dot {
    animation: none;
  }
}

@media print {
  #tts-reader-bar { display: none !important; }
  body.tts-reader-active { padding-bottom: 0 !important; }
}

/* Windows High Contrast and similar forced-colour modes discard author
   background-color and box-shadow outright, which would erase the highlight
   entirely — the reader would appear to do nothing. Outlines survive, and
   `Highlight` is the system colour meant for exactly this. */
@media (forced-colors: active) {
  .tts-word.tts-word-active,
  .tts-word.tts-sentence-active,
  .tts-block-active {
    outline: 2px solid Highlight;
    outline-offset: 1px;
    forced-color-adjust: none;
  }
  .tts-word.tts-word-active {
    outline-width: 3px;
  }
}