/**
 * main.css
 *
 * Layout is a fixed top bar plus a two-column body: image stage on the left,
 * control sidebar on the right. Everything is driven by the custom properties
 * in :root — change those to re-skin the app without hunting through rules.
 */

:root {
  --bg: #17171b;
  --bg-raised: #232329;
  --bg-sunken: #101014;
  --line: #55555f;
  --line-soft: #3d3d46;

  /* The stage sits at a mid grey on purpose: it is the only value that lets
     BOTH a blown-white frame and a crushed-black one show their edge against
     the background. A dark canvas hides black borders, a light one hides white. */
  --stage: #77777c;
  --stage-edge: #5f5f65;

  /* Text ramp. The faintest step is the one that matters — it carries the
     hints and the step badges, so it is held around 9:1 against the panel.
     Anything dimmer than this reads as disabled rather than secondary. */
  --text: #ffffff;
  --text-dim: #dedee4;
  --text-faint: #b6b6c0;

  --accent: #f0f0f2;
  --accent-ink: #16161a;
  --warn: #ff8a6b;

  --radius: 3px;
  --sidebar-width: 340px;
  --topbar-height: 56px;

  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 13px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ------------------------------------------------------------------ *
 * Top bar
 * ------------------------------------------------------------------ */

.topbar {
  flex: 0 0 var(--topbar-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 0 16px;
  background: var(--bg-raised);
  border-bottom: 1px solid var(--line);
}

/* The brand is a link back to this same page, so clicking it reloads the app. */
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  text-decoration: none;
  color: inherit;
  border-radius: var(--radius);
  transition: opacity 120ms;
}

.brand:hover { opacity: 0.68; }
.brand:active { opacity: 0.45; }

.brand:focus-visible {
  outline: 1px solid #6a6a78;
  outline-offset: 5px;
}

.brand__mark {
  width: 18px;
  height: 18px;
  flex: none;
  background: var(--text);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.brand__name {
  margin: 0;
  font-family: var(--mono);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  white-space: nowrap;
}

.brand__name em {
  font-style: normal;
  font-weight: 400;
  color: var(--text-faint);
}

.topbar__actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ------------------------------------------------------------------ *
 * Buttons
 * ------------------------------------------------------------------ */

.btn {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 7px 12px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 120ms, border-color 120ms, color 120ms;
  user-select: none;
}

.btn:hover { background: #2c2c34; border-color: #55555f; }
.btn:active,
.btn.is-active { background: var(--text); color: var(--accent-ink); border-color: var(--text); }

.btn--quiet { color: var(--text-dim); }

.btn--accent { border-color: #4a4a52; }

.btn--solid {
  background: var(--accent);
  color: var(--accent-ink);
  border-color: var(--accent);
  font-weight: 600;
}
.btn--solid:hover { background: #fff; border-color: #fff; }

.export {
  display: flex;
  align-items: stretch;
  gap: 6px;
  margin-left: 6px;
  padding-left: 14px;
  border-left: 1px solid var(--line);
}

.export__format {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text-dim);
  background: var(--bg-sunken);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 8px;
  cursor: pointer;
}

/* ------------------------------------------------------------------ *
 * Layout
 * ------------------------------------------------------------------ */

.layout {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  min-height: 0;
}

/* ------------------------------------------------------------------ *
 * Stage
 * ------------------------------------------------------------------ */

.stage {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--stage);
  overflow: hidden;
  min-width: 0;

  /* The viewer handles wheel and drag itself, so the browser must not claim
     them for scrolling. The grab/grabbing cursor is set from viewer.js. */
  touch-action: none;
}

.stage.is-dragover::after {
  content: "";
  position: absolute;
  inset: 12px;
  border: 1px dashed rgba(0, 0, 0, 0.45);
  border-radius: var(--radius);
  pointer-events: none;
}

/* A hairline plus a soft drop shadow, so the frame edge is legible whether the
   image ends in white or in black.
   Size comes from viewer.layout() (the fit) and zoom/pan from a transform on
   top, so no max-width here — it would fight the transform. No transition
   either: panning must track the cursor exactly. */
.stage__canvas {
  display: block;
  outline: 1px solid var(--stage-edge);
  box-shadow: 0 10px 34px rgba(0, 0, 0, 0.45);
  will-change: transform;
  user-select: none;
  -webkit-user-drag: none;
}

body:not(.has-image) .stage__canvas { display: none; }

/* The stage is mid grey now, so the status line needs its own dark plate
   rather than relying on a gradient over the background. */
.status {
  position: absolute;
  left: 10px;
  bottom: 10px;
  margin: 0;
  padding: 5px 9px;
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  background: rgba(16, 16, 20, 0.86);
  pointer-events: none;
}

.status:empty { display: none; }
.status.is-error { color: var(--warn); }

/* ------------------------------------------------------------------ *
 * Drop zone
 * ------------------------------------------------------------------ */

/* Sits on the mid-grey stage, so everything here is dark-on-grey. */
.dropzone {
  position: absolute;
  inset: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px dashed rgba(0, 0, 0, 0.32);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 140ms, background 140ms;
}

body.has-image .dropzone { display: none; }

.dropzone:hover,
.dropzone.is-dragover {
  border-color: rgba(0, 0, 0, 0.55);
  background: rgba(0, 0, 0, 0.06);
}

.dropzone__inner { text-align: center; }

.dropzone__icon {
  width: 34px;
  height: 34px;
  margin: 0 auto 18px;
  border: 1px solid rgba(0, 0, 0, 0.5);
  border-radius: var(--radius);
  position: relative;
}

.dropzone__icon::after {
  content: "";
  position: absolute;
  inset: 7px;
  border: 1px solid rgba(0, 0, 0, 0.5);
  border-radius: 50%;
}

.dropzone__title {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #17171b;
}

.dropzone__sub {
  margin: 0;
  font-size: 12px;
  color: rgba(0, 0, 0, 0.62);
}

/* ------------------------------------------------------------------ *
 * Sidebar
 * ------------------------------------------------------------------ */

.sidebar {
  display: flex;
  flex-direction: column;
  min-height: 0;
  background: var(--bg-raised);
  border-left: 1px solid var(--line);
}

.panel {
  flex: 1;
  overflow-y: auto;
  padding: 4px 0 12px;
  scrollbar-width: thin;
  scrollbar-color: #303036 transparent;
}

.panel::-webkit-scrollbar { width: 9px; }
.panel::-webkit-scrollbar-thumb {
  background: #86868f;
  border: 3px solid var(--bg-raised);
  border-radius: 99px;
}

/* ------------------------------------------------------------------ *
 * Footnote
 *
 * One line at the bottom of the sidebar that expands into a panel on hover.
 * The panel is absolutely positioned so it costs no layout space, and it opens
 * on :focus-within as well as :hover so it is reachable by keyboard and by tap
 * on touch devices, where hover does not exist.
 * ------------------------------------------------------------------ */

.footnote {
  position: relative;
  flex: none;
  border-top: 1px solid var(--line-soft);
}

.footnote__trigger {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 10px 16px;
  margin: 0;
  background: none;
  border: none;
  font-family: inherit;
  font-size: 11px;
  color: var(--text-faint);
  text-align: left;
  cursor: help;
  transition: color 120ms;
}

.footnote:hover .footnote__trigger,
.footnote:focus-within .footnote__trigger {
  color: var(--text-dim);
}

.footnote__trigger:focus-visible {
  outline: 1px solid #4d4d55;
  outline-offset: -2px;
}

.footnote__icon {
  flex: none;
  display: grid;
  place-items: center;
  width: 14px;
  height: 14px;
  border: 1px solid currentColor;
  border-radius: 50%;
  font-family: var(--mono);
  font-size: 9px;
  font-style: italic;
  line-height: 1;
}

.footnote__panel {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 12px;
  right: 12px;
  z-index: 20;

  padding: 14px 16px;
  background: var(--bg-sunken);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 14px 38px rgba(0, 0, 0, 0.6);

  max-height: 60vh;
  overflow-y: auto;

  opacity: 0;
  visibility: hidden;
  transform: translateY(4px);
  transition: opacity 130ms, transform 130ms, visibility 130ms;
}

/* Bridges the gap between trigger and panel so moving the pointer up into the
   panel does not drop the hover.
   It lives on .footnote, NOT on the panel: the panel scrolls, and an
   absolutely positioned descendant of a scrolling box counts toward its
   scrollHeight — which produced a phantom scrollbar on content that fit. */
.footnote::after {
  content: "";
  position: absolute;
  bottom: 100%;
  left: 0;
  right: 0;
  height: 10px;
}

.footnote:hover .footnote__panel,
.footnote:focus-within .footnote__panel {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.footnote__title {
  margin: 0 0 7px;
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.footnote__title ~ .footnote__title {
  margin-top: 14px;
}

.footnote__list {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 5px 12px;
  margin: 0;
  font-size: 11px;
  line-height: 1.4;
}

.footnote__list dt { color: var(--text); white-space: nowrap; }
.footnote__list dd { margin: 0; color: var(--text-faint); }

.footnote__list kbd {
  font-family: var(--mono);
  font-size: 10px;
  padding: 1px 4px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--bg-raised);
}

.footnote__text {
  margin: 0;
  font-size: 11px;
  line-height: 1.5;
  color: var(--text-dim);
}

/* Sits inside the hover panel. The panel stays open while the pointer is over
   it, and :focus-within keeps it open when this link is tabbed to. */
.footnote__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 11px;
  color: var(--text-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 120ms, border-color 120ms;
}

.footnote__link:hover {
  color: var(--text);
  border-bottom-color: var(--line);
}

.footnote__link:focus-visible {
  outline: 1px solid #6a6a78;
  outline-offset: 3px;
}

.footnote__glyph {
  flex: none;
  display: block;
}

/* Closing plate. Uppercase letterspaced mono so it reads as a stamped marking
   rather than a sentence — the same type language as the group headings and
   the brand, so it needs no vocabulary of its own. */
.footnote__plate {
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  line-height: 1.6;
  text-align: center;
  color: var(--text-faint);
}

.footnote__plate a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 120ms, border-color 120ms;
}

.footnote__plate a:hover {
  color: var(--text);
  border-bottom-color: var(--line);
}

.footnote__plate a:focus-visible {
  outline: 1px solid #6a6a78;
  outline-offset: 3px;
}

/* ------------------------------------------------------------------ *
 * Control groups
 * ------------------------------------------------------------------ */

.group {
  padding: 14px 16px 6px;
  border-bottom: 1px solid var(--line-soft);
}

.group:last-child { border-bottom: none; }

/* Numbered because the panel reads top to bottom as the editing sequence. */
.group__title {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin: 0 0 13px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text);
}

.group__step {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--accent-ink);
  background: var(--text-dim);
  border-radius: 2px;
  padding: 2px 5px;
}

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

.control { margin-bottom: 15px; }
.control.is-hidden { display: none; }

.control__head {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 6px;
}

.control__label {
  flex: 1;
  font-size: 12.5px;
  color: var(--text-dim);
  transition: color 120ms;
}

.control.is-modified .control__label { color: var(--text); }

.control__value {
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
}

.control.is-modified .control__value { color: var(--text); }

.control__hint {
  margin: 6px 0 0;
  font-size: 11px;
  line-height: 1.5;
  color: var(--text-faint);
}

/* --- range --- */

.control__range {
  -webkit-appearance: none;
  appearance: none;
  display: block;
  width: 100%;
  height: 16px;
  background: transparent;
  cursor: pointer;
  margin: 0;
}

.control__range::-webkit-slider-runnable-track {
  height: 2px;
  background: #86868f;
  border-radius: 2px;
}
.control__range::-moz-range-track {
  height: 2px;
  background: #86868f;
  border-radius: 2px;
}

.control__range::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 12px;
  height: 12px;
  margin-top: -5px;
  border-radius: 50%;
  background: var(--text-dim);
  border: none;
  transition: background 120ms, transform 120ms;
}
.control__range::-moz-range-thumb {
  width: 11px;
  height: 11px;
  border: none;
  border-radius: 50%;
  background: var(--text-dim);
}

.control__range:hover::-webkit-slider-thumb { background: var(--text); }
.control__range:active::-webkit-slider-thumb { transform: scale(1.25); background: #fff; }
.control__range:hover::-moz-range-thumb { background: var(--text); }

.control.is-modified .control__range::-webkit-slider-thumb { background: var(--text); }
.control.is-modified .control__range::-moz-range-thumb { background: var(--text); }

.control__range:focus-visible { outline: 1px solid #4d4d55; outline-offset: 4px; }

/* --- select --- */

.control__select {
  width: 100%;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--text);
  background: var(--bg-sunken);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 7px 8px;
  cursor: pointer;
}

.control__select:hover { border-color: #38383e; }
.control__select:focus-visible { outline: 1px solid #4d4d55; outline-offset: 1px; }

/* --- toggle --- */

.control__toggle { display: none; }

.switch {
  position: relative;
  width: 30px;
  height: 16px;
  flex: none;
  border-radius: 99px;
  background: #78788a;
  border: 1px solid var(--line);
  cursor: pointer;
  transition: background 140ms, border-color 140ms;
}

.switch__knob {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--text-dim);
  transition: transform 140ms, background 140ms;
}

/* `is-on` is set by panel.js — see the note in Panel.sync(). */
.control--toggle.is-on .switch {
  background: var(--text);
  border-color: var(--text);
}

.control--toggle.is-on .switch__knob {
  transform: translateX(14px);
  background: var(--accent-ink);
}

/* ------------------------------------------------------------------ *
 * Export overlay
 * ------------------------------------------------------------------ */

.overlay {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  background: rgba(6, 6, 7, 0.82);
  backdrop-filter: blur(2px);
  z-index: 50;
}

.overlay.is-visible { display: flex; }

.overlay__box {
  width: min(340px, 80vw);
  padding: 22px;
  background: var(--bg-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.overlay__text {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--text-dim);
}

.overlay__track {
  height: 2px;
  background: #2a2a30;
  overflow: hidden;
}

.overlay__bar {
  height: 100%;
  width: 0;
  background: var(--text);
  transition: width 160ms linear;
}

/* ------------------------------------------------------------------ *
 * Narrow screens — stack the panel under the image
 * ------------------------------------------------------------------ */

@media (max-width: 860px) {
  body { overflow: auto; }
  .layout { grid-template-columns: 1fr; }
  .stage { height: 52vh; }
  .sidebar { border-left: none; border-top: 1px solid var(--line); }
  .topbar { flex-wrap: wrap; height: auto; flex: none; padding: 10px 12px; }
}