/*
 * Interactive theory figures (theory.html, static/js/theory/): the Interactive and Animation switch above each
 * animation panel, and the widget that replaces the panel in interactive mode: a 16:9 stage like the panel, the hint
 * and Reset line under it, and the sliders and readouts. Uses the tokens of index.css.
 *
 * core.js marks the panel's parent as .hx-fig-host with data-fig-mode="interactive" or "animation", and with
 * data-fig-ready once the widget has mounted; until then the poster stays in place.
 */

/* ---------- Which of the two shows ---------- */

.hx-fig-host[data-fig-mode="interactive"][data-fig-ready] > .hx-anim-media,
.hx-fig-host[data-fig-mode="interactive"] > .hx-hint-below,
.hx-fig-host:not([data-fig-mode="interactive"]) > .hx-widget {
  display: none;
}

/* The panel is the containing block of its absolutely placed video in either mode, also before (or without) a
   video group, so the video never escapes its box. */
.hx-fig-host > .hx-anim-media {
  position: relative;
}

/* While the widget loads, the poster stands in for it and is not a play target. */
.hx-fig-host[data-fig-mode="interactive"] > .hx-anim-media {
  cursor: default;
}

/* ---------- The switch ---------- */

.hx-fig-bar {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 0.5rem;
}

.hx-fig-switch {
  display: inline-flex;
  gap: 2px;
  padding: 2px;
  border: 1px solid var(--hx-line);
  border-radius: 999px;
  background: var(--hx-surface-2);
}

.hx-fig-switch button {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  padding: 0.28rem 0.75rem;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--hx-muted);
  font-size: 0.78rem;
  font-weight: 600;
  line-height: 1.2;
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease, padding 0.15s ease;
  -webkit-tap-highlight-color: transparent;
}

.hx-fig-switch .fa-solid {
  font-size: 0.85em;
}

.hx-fig-switch button[aria-pressed="true"] {
  background: var(--hx-surface);
  box-shadow: 0 1px 2px rgba(31, 43, 48, 0.16);
  color: var(--hx-ink);
  cursor: default;
}

/* The live figure's glyph takes the Hexels orange; in Animation mode the cue dot on "Interactive" is the only
   accent, so the eye goes to one place. */
.hx-fig-switch button[data-mode="interactive"][aria-pressed="true"] .fa-solid {
  color: var(--hx-ours);
}

@media (hover: hover) {
  .hx-fig-switch button[aria-pressed="false"]:hover {
    color: var(--hx-ink);
  }

  .hx-widget .hx-fig-switch button[aria-pressed="false"]:hover {
    background: var(--hx-surface-2);
  }
}

/* The two animations of the honeycomb row: the switch shares the line of its panel's label. */
.hx-anim-item.hx-fig-host {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  column-gap: 0.75rem;
}

.hx-anim-item.hx-fig-host > * {
  grid-column: 1 / -1;
}

.hx-anim-item.hx-fig-host > .hx-anim-label {
  grid-column: 1;
  grid-row: 1;
  margin-bottom: 0.5rem;
}

.hx-anim-item.hx-fig-host > .hx-fig-bar {
  grid-column: 2;
  grid-row: 1;
}

/* Phones: the label takes a line of its own above the switch, so the switch (40 px targets) never squeezes it. */
@media screen and (max-width: 600px) {
  .hx-anim-item.hx-fig-host > .hx-anim-label,
  .hx-anim-item.hx-fig-host > .hx-fig-bar {
    grid-column: 1 / -1;
    grid-row: auto;
  }

  .hx-anim-item.hx-fig-host > .hx-anim-label {
    margin-bottom: 0.25rem;
  }
}

/* ---------- The widget: stage, hint and Reset ---------- */

.hx-widget {
  container: hx-fig / inline-size;
}

/* Exactly 16:9 inside the border, like the 1440 x 810 animations, so switching views never moves the page. */
.hx-fig-stage {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--hx-line);
  border-radius: var(--hx-radius);
  background: #fff;
}

.hx-fig-stage::before {
  content: "";
  display: block;
  padding-top: 56.25%;
}

.hx-fig-drawing {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
}

/* Up and down swipes scroll the page unless they start on a handle that moves freely (dragHandles cancels only
   those touches); sideways moves stay with the figure, for its sliders and dividers. */
.hx-fig-draggable {
  touch-action: pan-y pinch-zoom;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

/* The hint wraps beside Reset rather than pushing it onto a line of its own. */
.hx-fig-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.4rem 1rem;
  margin-top: 0.55rem;
}

.hx-fig-hint {
  display: inline-flex;
  flex: 1 1 auto;
  align-items: baseline;
  gap: 0.45rem;
  min-width: 0;
  margin: 0;
  color: var(--hx-muted);
  font-size: 0.8rem;
  line-height: 1.45;
}

.hx-fig-hint .fa-solid {
  font-size: 0.72rem;
}

.hx-fig-reset {
  display: inline-flex;
  flex: none;
  align-items: center;
  gap: 0.4rem;
  margin-left: auto;
  padding: 0.22rem 0.75rem;
  border: 1px solid var(--hx-line);
  border-radius: 999px;
  background: var(--hx-surface);
  color: var(--hx-ink);
  font-size: 0.78rem;
  line-height: 1.4;
  cursor: pointer;
  transition: border-color 0.15s ease;
}

.hx-fig-reset .fa-solid {
  color: var(--hx-muted);
  font-size: 0.85em;
}

@media (hover: hover) {
  .hx-fig-reset:hover {
    border-color: var(--hx-dark);
  }
}

/* ---------- Controls ---------- */

/* Groups share the row (as many columns as fit at 10rem or more); a widget can fix its columns with --hx-fig-grid,
   and a group made with wide: true spans the row. */
.hx-fig-controls {
  display: grid;
  grid-template-columns: var(--hx-fig-grid, repeat(auto-fit, minmax(10rem, 1fr)));
  gap: 0.85rem 1.5rem;
  margin-top: 0.8rem;
}

.hx-fig-controls:empty {
  display: none;
}

/* Narrow widgets (phones, and the mid-width two-column layout) stack the groups with full-width sliders. */
@container hx-fig (max-width: 30rem) {
  .hx-fig-controls {
    grid-template-columns: minmax(0, 1fr);
    row-gap: 0.7rem;
  }
}

/* alpha_compositing keeps one column per Hexel only where its sliders stay long enough for steps of 0.01. */
@container hx-fig (max-width: 38rem) {
  .hx-widget[data-widget="alpha_compositing"] .hx-fig-controls {
    grid-template-columns: minmax(0, 1fr);
    row-gap: 0.7rem;
  }
}

/* A switch inside a widget (the honeycomb figures' view) is a segmented control like the page's other in-figure
   toggles, so it does not read as the Animation and Interactive switch above the figure. */
.hx-widget .hx-fig-switch {
  gap: 0;
  padding: 0;
  overflow: hidden;
  background: var(--hx-surface);
}

.hx-widget .hx-fig-switch button {
  border-radius: 0;
}

.hx-widget .hx-fig-switch button + button {
  border-left: 1px solid var(--hx-line);
}

.hx-widget .hx-fig-switch button[aria-pressed="true"] {
  background: var(--hx-dark);
  box-shadow: none;
  color: #fff;
}

.hx-fig-group {
  min-width: 0;
  margin: 0;
  padding: 0;
  border: 0;
}

.hx-fig-group.is-wide {
  grid-column: 1 / -1;
}

.hx-fig-legend {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  width: 100%;
  margin: 0 0 0.15rem;
  padding: 0;
  color: var(--hx-ink);
  font-size: 0.8rem;
  font-weight: 600;
}

.hx-fig-swatch {
  flex: none;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
  box-shadow: inset 0 0 0 1px rgba(38, 63, 72, 0.35);
}

.hx-fig-legend-value {
  margin-left: auto;
  color: var(--hx-muted);
  font-weight: 400;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.hx-fig-slider {
  display: grid;
  grid-template-columns: 1.6rem minmax(0, 1fr) 2.3rem;
  align-items: center;
  column-gap: 0.45rem;
}

.hx-fig-slider label {
  color: var(--hx-ink);
  cursor: pointer;
}

/* A thin track filled in the slider's accent up to the thumb's center (--hx-fig-share, from 0 to 1, set by slider()
   in core.js), and a white thumb with an ink ring: the same in every browser, whatever the accent's lightness. */
.hx-fig-slider input[type="range"] {
  --hx-fig-thumb: 14px;
  width: 100%;
  height: 1.7rem;
  margin: 0;
  padding: 0;
  background: transparent;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

.hx-fig-slider input[type="range"]::-webkit-slider-runnable-track {
  height: 4px;
  border-radius: 999px;
  --hx-fig-stop: calc(var(--hx-fig-thumb) / 2 + var(--hx-fig-share, 0) * (100% - var(--hx-fig-thumb)));
  background: linear-gradient(to right, var(--hx-fig-accent, var(--hx-select)) var(--hx-fig-stop), var(--hx-line) var(--hx-fig-stop));
}

.hx-fig-slider input[type="range"]::-webkit-slider-thumb {
  width: var(--hx-fig-thumb);
  height: var(--hx-fig-thumb);
  margin-top: calc((4px - var(--hx-fig-thumb)) / 2);
  border: 1.5px solid var(--hx-ink);
  border-radius: 50%;
  background: var(--hx-surface);
  box-shadow: 0 1px 2px rgba(31, 43, 48, 0.2);
  -webkit-appearance: none;
  appearance: none;
}

.hx-fig-slider input[type="range"]::-moz-range-track {
  height: 4px;
  border-radius: 999px;
  background: var(--hx-line);
}

.hx-fig-slider input[type="range"]::-moz-range-progress {
  height: 4px;
  border-radius: 999px;
  background: var(--hx-fig-accent, var(--hx-select));
}

.hx-fig-slider input[type="range"]::-moz-range-thumb {
  box-sizing: border-box;
  width: var(--hx-fig-thumb);
  height: var(--hx-fig-thumb);
  border: 1.5px solid var(--hx-ink);
  border-radius: 50%;
  background: var(--hx-surface);
  box-shadow: 0 1px 2px rgba(31, 43, 48, 0.2);
}

.hx-fig-slider input[type="range"]:focus-visible {
  outline: none;
}

.hx-fig-slider input[type="range"]:focus-visible::-webkit-slider-thumb {
  box-shadow: 0 0 0 3px rgba(93, 112, 174, 0.4);
}

.hx-fig-slider input[type="range"]:focus-visible::-moz-range-thumb {
  box-shadow: 0 0 0 3px rgba(93, 112, 174, 0.4);
}

.hx-fig-value {
  color: var(--hx-ink);
  font-size: 0.82rem;
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.hx-fig-readout {
  grid-column: 1 / -1;
  margin: 0;
  color: var(--hx-ink);
  font-size: 0.85rem;
  line-height: 1.5;
}

.hx-fig-readout-main,
.hx-fig-readout-note {
  display: block;
}

.hx-fig-readout-main .fa-solid {
  color: var(--hx-select);
}

.hx-fig-readout.is-violated .fa-solid {
  color: var(--hx-ours);
}

.hx-fig-readout-note {
  color: var(--hx-muted);
  font-size: 0.8rem;
}

/* Inline math of labels and readouts, in the serif of the figures. */
.hx-math {
  font-family: "STIX Two Text", "Times New Roman", Times, serif;
  font-size: 1.12em;
  line-height: 1;
  white-space: nowrap;
}

.hx-math sub,
.hx-math sup {
  font-size: 0.7em;
}

/* ---------- Touch and motion ---------- */

/* Fingers get 40 px targets: the switch, Reset and every slider. */
@media (pointer: coarse) {
  .hx-fig-switch button,
  .hx-fig-reset {
    min-height: 40px;
  }

  .hx-fig-switch button {
    padding-inline: 0.95rem;
  }

  .hx-fig-slider input[type="range"] {
    --hx-fig-thumb: 22px;
    height: 40px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .hx-fig-switch button,
  .hx-fig-reset {
    transition: none;
  }
}

/* ---------- The cue toward the interactive figure ---------- */

/* A honey dot after the word "Interactive" while a figure shows its animation, until the visitor first opens an
   interactive figure; it pulses three times when the figure first comes well into view, then rests. The option
   keeps room for it only while it shows. */
.hx-fig-switch button {
  position: relative;
}

.hx-fig-cue {
  display: none;
  position: absolute;
  top: 50%;
  right: 0.5rem;
  width: 7px;
  height: 7px;
  margin-top: -3.5px;
  border-radius: 50%;
  background: var(--hx-ours);
  pointer-events: none;
}

.hx-fig-host[data-fig-mode="animation"]:not(.hx-fig-tried) > .hx-fig-bar .hx-fig-cue {
  display: block;
}

.hx-fig-host[data-fig-mode="animation"]:not(.hx-fig-tried) > .hx-fig-bar button[data-mode="interactive"] {
  padding-right: 1.25rem;
}

.hx-fig-cue.is-pulsing {
  animation: hx-fig-cue-pulse 1.6s ease-out 3;
}

@keyframes hx-fig-cue-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(205, 115, 83, 0.55);
  }

  100% {
    box-shadow: 0 0 0 10px rgba(205, 115, 83, 0);
  }
}

/* "Try it yourself", beside the switch after a few seconds of an animation, then gone; a click on it opens the
   interactive figure. It takes no room in the bar (its text overflows its empty box to the left), so the line never
   reflows around it; the narrowest phones, which leave no room beside the switch, show it just above the switch. The
   text is a darker honey than the glyph, for contrast on white and on the grey bands. */
.hx-fig-nudge {
  display: inline-flex;
  flex: 0 0 0;
  justify-content: flex-end;
  align-items: center;
  gap: 0.35em;
  width: 0;
  margin-right: 0.6rem;
  color: #a9573c;
  font-size: 0.78rem;
  font-weight: 600;
  white-space: nowrap;
  opacity: 0;
  transform: translateX(6px);
  transition: opacity 0.35s ease, transform 0.35s ease;
  pointer-events: none;
}

.hx-fig-nudge .fa-solid {
  color: var(--hx-ours);
}

.hx-fig-nudge.is-shown {
  opacity: 1;
  transform: none;
  pointer-events: auto;
  cursor: pointer;
}

@media screen and (max-width: 379px) {
  .hx-fig-bar {
    position: relative;
  }

  .hx-fig-nudge {
    position: absolute;
    right: 0.4rem;
    bottom: calc(100% + 0.2rem);
    width: auto;
    margin: 0;
    transform: translateY(4px);
  }
}

.hx-fig-host:not([data-fig-mode="animation"]) .hx-fig-nudge,
.hx-fig-host.hx-fig-tried .hx-fig-nudge {
  display: none;
}

@media (prefers-reduced-motion: reduce) {
  .hx-fig-cue.is-pulsing {
    animation: none;
  }

  .hx-fig-nudge {
    transition: none;
  }
}