:root {
  --bg: #0f1115;
  --panel: #1a1d24;
  --line: #2a2f3a;
  --accent: #4c8dff;
  --text: #e6e9ef;
  --muted: #8b93a3;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
}

header {
  padding: 18px 24px;
  border-bottom: 1px solid var(--line);
}
header h1 { margin: 0; font-size: 20px; }
header .sub { margin: 4px 0 0; color: var(--muted); font-size: 13px; }

main {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 20px;
  padding: 20px 24px;
  align-items: start;
}

/* ---- stage / canvas ---- */
.drop-zone {
  border: 2px dashed var(--line);
  border-radius: 12px;
  padding: 20px;
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  transition: border-color .15s, background .15s;
}
.drop-zone.over { border-color: var(--accent); background: rgba(76, 141, 255, .06); }
.drop-hint { color: var(--muted); font-size: 13px; margin: 0; }

/* ---- stage: viewport cố định, ảnh pan/zoom phía trong ---- */
.canvas-wrap {
  position: relative;
  width: 100%;
  height: 68vh;
  overflow: hidden;
  background: #0a0b0e;
  border-radius: 8px;
  touch-action: none;
  cursor: grab;
}
.canvas-wrap.grabbing { cursor: grabbing; }
.photo-canvas {
  position: absolute;
  left: 50%;
  top: 50%;
  transform-origin: center center;
  display: block;
  image-rendering: auto;
}

/* ---- khung crop cố định + scrim làm mờ ngoài khung ---- */
.crop-frame {
  position: absolute;
  box-shadow: 0 0 0 9999px rgba(0, 0, 0, .55);
  outline: 1px solid rgba(255, 255, 255, .9);
  pointer-events: none;
  z-index: 2;
}

/* ---- điều khiển zoom ---- */
.zoom-ctl {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 10px;
  background: rgba(20, 23, 30, .85);
  border: 1px solid var(--line);
  border-radius: 999px;
  z-index: 3;
}
.zoom-ctl input[type="range"] { width: 140px; accent-color: var(--accent); }
.zoom-ctl button {
  width: 26px; height: 26px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: #232733;
  color: var(--text);
  font-size: 16px;
  line-height: 1;
  cursor: pointer;
}

/* ---- khung hướng dẫn đầu-vai (overlay trong khung, không bắt pointer) ---- */
.crop-guide {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: visible;
}
.crop-frame.hide-guide .crop-guide { display: none; }
.guide-head {
  fill: rgba(255, 211, 78, .08);
  stroke: #ffd34e;
  stroke-width: 1.4;
  vector-effect: non-scaling-stroke;
  opacity: .9;
}
.guide-line {
  stroke: #ffd34e;
  stroke-width: 1;
  vector-effect: non-scaling-stroke;
  opacity: .6;
}
.guide-line.eye { stroke-width: 1.6; opacity: .95; } /* đường mắt = mốc chính */
.guide-line.center { opacity: .4; }
.guide-line.dash { stroke-dasharray: 4 3; }

/* ---- panel ---- */
.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.group { display: flex; flex-direction: column; gap: 10px; }
.group h2 { margin: 0; font-size: 13px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
.group label { font-size: 13px; display: flex; flex-direction: column; gap: 6px; }

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #232733;
  color: var(--text);
  font-size: 14px;
  cursor: pointer;
}
.btn:hover { border-color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 600; }
.btn.primary:disabled { opacity: .5; cursor: not-allowed; }
.btn.ghost.active { border-color: var(--accent); color: var(--accent); }
.file-btn { width: 100%; }

#chromaControls { display: flex; flex-direction: column; gap: 10px; }

.size-row, .bg-row { display: flex; gap: 8px; }
.size-btn, .bg-btn {
  flex: 1;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #232733;
  color: var(--text);
  cursor: pointer;
  font-size: 13px;
}
.size-btn.active, .bg-btn.active { border-color: var(--accent); color: var(--accent); }

.check {
  display: flex;
  flex-direction: row !important;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--muted);
  cursor: pointer;
}
.check input { accent-color: var(--accent); width: auto; }

.status { margin: 0; font-size: 12px; color: var(--muted); min-height: 16px; }

@media (max-width: 760px) {
  main { grid-template-columns: 1fr; }
}