/* ---------------------------------------------------------------- tokens */
:root {
  --bg: #eef1f4;
  --panel: #ffffff;
  --panel2: #e3e8ed;
  --text: #14181d;
  --muted: #6a7480;
  --border: #d9dfe6;
  --accent: #e2b93b;
  --accent-ink: #1c1600;
  --shadow: 0 1px 2px rgba(20, 24, 29, .06);
}
:root.dark {
  --bg: #0d1013;
  --panel: #151a1f;
  --panel2: #1d232a;
  --text: #e7ebef;
  --muted: #8791a0;
  --border: #262d35;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font: 400 14px/1.45 "DM Sans", system-ui, -apple-system, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.mono { font-family: "JetBrains Mono", ui-monospace, monospace; }
.muted { color: var(--muted); }

input[type=range] { accent-color: var(--accent); width: 100%; margin: 0; }

/* ---------------------------------------------------------------- shell */
.root {
  height: 100dvh;
  display: flex;
  flex-direction: column;
  position: relative;
}

.topbar {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}
.logo {
  width: 14px;
  height: 14px;
  border: 1px solid var(--text);
  background: repeating-conic-gradient(var(--text) 0 25%, transparent 0 50%) 0 0 / 6px 6px;
}
.wordmark { margin: 0; font-size: 15px; font-weight: 600; letter-spacing: -.01em; }
.status { font-size: 12px; color: var(--muted); }
.spacer { flex: 1; }

.workspace {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: row-reverse;
}

/* ---------------------------------------------------------------- buttons */
.btn {
  height: 32px;
  padding: 0 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font: inherit;
  font-size: 13px;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  transition: border-color .12s, background .12s, filter .12s;
}
.btn:hover:not(:disabled) { border-color: var(--muted); }
.btn:disabled { opacity: .45; cursor: not-allowed; }
.btn-sm { height: 28px; padding: 0 10px; font-size: 12px; }
.btn-icon { width: 32px; padding: 0; }
.btn-primary {
  height: 40px;
  font-weight: 600;
  font-size: 14px;
  color: var(--accent-ink);
  background: var(--accent);
  border: 0;
  border-radius: 8px;
}
.btn-primary:hover:not(:disabled) { filter: brightness(1.05); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------------------------------------------------------------- stage */
.stage {
  position: relative;
  flex: 999 1 420px;
  min-width: 0;
  overflow: hidden;
  background: var(--panel2);
  user-select: none;
  touch-action: pan-y;
  cursor: ew-resize;
}
.stage.panning { touch-action: none; cursor: grab; }
.stage.empty { cursor: default; }

.viewer { position: absolute; inset: 0; }
.viewer[hidden] { display: none; }
.layer {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.layer canvas { image-rendering: pixelated; }
#orig { box-shadow: 0 8px 30px rgba(0, 0, 0, .18); }

.divider { position: absolute; top: 0; bottom: 0; width: 0; pointer-events: none; }
.divider-line { position: absolute; top: 0; bottom: 0; left: -1px; width: 2px; background: var(--accent); }
.handle {
  position: absolute;
  top: 50%;
  left: -22px;
  margin-top: -22px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-ink);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  font-size: 11px;
  font-weight: 600;
  box-shadow: 0 2px 10px rgba(0, 0, 0, .3);
  pointer-events: auto;
  cursor: ew-resize;
  touch-action: none;
}

.tag {
  position: absolute;
  top: 12px;
  padding: 3px 8px;
  border-radius: 4px;
  font-size: 11px;
  pointer-events: none;
}
.tag-before { left: 12px; background: rgba(0, 0, 0, .55); color: #fff; }
.tag-after { right: 12px; background: var(--accent); color: var(--accent-ink); }

.zoombar {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 4px;
  border-radius: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  cursor: default;
}
.zbtn {
  width: 32px;
  height: 32px;
  border: 0;
  background: transparent;
  color: var(--text);
  border-radius: 6px;
  cursor: pointer;
  font: inherit;
  font-size: 16px;
}
.zbtn-wide { width: auto; min-width: 56px; font-size: 12px; }
.zbtn:hover { background: var(--panel2); }

/* ---------------------------------------------------------------- dropzone */
.dropzone {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.dropzone[hidden] { display: none; }
.drop-card {
  width: 100%;
  max-width: 460px;
  padding: 40px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
  border: 1.5px dashed var(--muted);
  border-radius: 12px;
  cursor: pointer;
  transition: border-color .12s;
}
.drop-card:hover { border-color: var(--accent); }
.drop-icon {
  width: 48px;
  height: 48px;
  border: 1px solid var(--muted);
  border-radius: 6px;
  opacity: .6;
  background: repeating-conic-gradient(var(--muted) 0 25%, transparent 0 50%) 0 0 / 8px 8px;
}
.drop-title { margin: 0; font-size: 16px; font-weight: 600; }
.drop-sub { margin: 0; font-size: 13px; color: var(--muted); }

.drag-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 600;
  background: rgba(226, 185, 59, .18);
  border: 3px solid var(--accent);
  pointer-events: none;
}
.drag-overlay[hidden] { display: none; }

/* ---------------------------------------------------------------- panel */
.panel {
  flex: 1 1 300px;
  max-width: 360px;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--panel);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
}

.group {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  border-bottom: 1px solid var(--border);
}
.group:last-child { border-bottom: 0; }
.group-head { display: flex; align-items: center; justify-content: space-between; }
.group-title {
  margin: 0;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--muted);
}
.row { display: flex; gap: 8px; }
.row > .btn { flex: 1; height: 40px; border-radius: 8px; }

/* thumbnails */
.thumbs { display: grid; grid-template-columns: repeat(auto-fill, minmax(64px, 1fr)); gap: 8px; }
.thumbs[hidden] { display: none; }
.thumb { position: relative; aspect-ratio: 1; }
.thumb-pick {
  width: 100%;
  height: 100%;
  padding: 0;
  border: 0;
  border-radius: 6px;
  overflow: hidden;
  background: var(--panel2);
  cursor: pointer;
  outline: 2px solid transparent;
  outline-offset: 2px;
}
.thumb-pick[aria-checked="true"] { outline-color: var(--accent); }
.thumb-pick img { width: 100%; height: 100%; object-fit: cover; display: block; pointer-events: none; }
.thumb-del {
  position: absolute;
  top: -6px;
  right: -6px;
  width: 20px;
  height: 20px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--text);
  color: var(--bg);
  font: inherit;
  font-size: 12px;
  line-height: 20px;
  cursor: pointer;
}

/* algorithm list */
.algos { display: flex; flex-direction: column; gap: 4px; }
.algo {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  min-height: 44px;
  padding: 8px 12px;
  text-align: left;
  font: inherit;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  transition: border-color .12s, background .12s;
}
.algo:hover { border-color: var(--muted); }
.algo[aria-checked="true"] { border-color: var(--accent); background: var(--panel2); }
.algo b { font-weight: 500; font-size: 14px; }
.algo span { color: var(--muted); font-size: 12px; }

/* parameters */
.field { display: flex; flex-direction: column; gap: 6px; }
.field[hidden] { display: none; }
.field-head { display: flex; justify-content: space-between; font-size: 13px; }

/* palettes */
.palettes { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; }
.palette {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 44px;
  padding: 8px 10px;
  text-align: left;
  font: inherit;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  transition: border-color .12s, background .12s;
}
.palette:hover { border-color: var(--muted); }
.palette[aria-checked="true"] { border-color: var(--accent); background: var(--panel2); }
.palette b { font-weight: 500; font-size: 13px; }
.swatch {
  display: flex;
  height: 10px;
  border: 1px solid var(--border);
  border-radius: 3px;
  overflow: hidden;
}
.swatch i { flex: 1; }

.custom-row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.custom-row[hidden] { display: none; }
.chip { position: relative; width: 44px; height: 44px; }
.chip input {
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
}
.chip button {
  position: absolute;
  top: -6px;
  right: -6px;
  width: 18px;
  height: 18px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--text);
  color: var(--bg);
  font: inherit;
  font-size: 11px;
  line-height: 18px;
  cursor: pointer;
}
.chip-add {
  width: 44px;
  height: 44px;
  border: 1px dashed var(--muted);
  border-radius: 8px;
  background: transparent;
  color: var(--text);
  font: inherit;
  font-size: 18px;
  cursor: pointer;
}
.chip-add:hover { border-color: var(--accent); }

/* ---------------------------------------------------------------- toast */
.toast {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  padding: 10px 16px;
  border-radius: 8px;
  background: var(--text);
  color: var(--bg);
  font-size: 13px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, .3);
  pointer-events: none;
  z-index: 10;
}
.toast[hidden] { display: none; }

/* ---------------------------------------------------------------- mobile */
@media (max-width: 760px) {
  .workspace { flex-direction: column; overflow-y: auto; }
  .stage { flex: 0 0 auto; height: 58dvh; min-height: 300px; }
  .panel {
    flex: 0 0 auto;
    max-width: none;
    overflow: visible;
    border-right: 0;
    border-top: 1px solid var(--border);
  }
  .status { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}