:root {
  --bg-0: #0b1020;
  --bg-1: #0f172a;
  --bg-2: #1e293b;
  --bg-3: #334155;
  --fg: #e2e8f0;
  --fg-dim: #94a3b8;
  --accent: #f472b6;
  --accent-2: #818cf8;
  --border: rgba(148, 163, 184, 0.18);
  --header-h: 52px;
  --palette-h: 52px;
  --layer-panel-w: 200px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  overflow: hidden;
  background: var(--bg-1);
  color: var(--fg);
  font-family: system-ui, -apple-system, sans-serif;
  font-size: 14px;
  user-select: none;
  -webkit-user-select: none;
}

/* ── Layout ─────────────────────────────────── */

.paint-layout {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

/* ── Header / toolbar ───────────────────────── */

.paint-header {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0 10px;
  /* leave room for the compact back button (fixed: left:10px, ~80px wide) */
  padding-left: 90px;
  height: var(--header-h);
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  flex-wrap: wrap;
  overflow: hidden;
}

.paint-title {
  display: flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  font-size: 15px;
  color: var(--fg);
  text-decoration: none;
  white-space: nowrap;
}

.paint-title span { font-size: 20px; }

.header-sep {
  width: 1px;
  height: 28px;
  background: var(--border);
  margin: 0 2px;
  flex-shrink: 0;
}

/* Tool buttons — lives in the left panel, stacked vertically */
#tool-buttons {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.tool-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid transparent;
  border-radius: 5px;
  background: transparent;
  color: var(--fg);
  font-size: 16px;
  cursor: pointer;
  transition: background 0.1s, border-color 0.1s;
  flex-shrink: 0;
}

.tool-btn:hover { background: var(--bg-3); border-color: var(--border); }
.tool-btn.active {
  background: rgba(244, 114, 182, 0.15);
  border-color: var(--accent);
  color: var(--accent);
}

/* Shape fill */
.shape-fill-group {
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--fg-dim);
  font-size: 12px;
  flex-shrink: 0;
}
.shape-fill-group input[type="checkbox"] {
  accent-color: var(--accent); width: 14px; height: 14px; cursor: pointer;
}

/* Brush size */
.size-group {
  display: flex;
  align-items: center;
  gap: 5px;
  flex-shrink: 0;
}
.size-group label { color: var(--fg-dim); font-size: 12px; white-space: nowrap; }
#brush-size { width: 72px; accent-color: var(--accent); cursor: pointer; }
#size-display { min-width: 18px; text-align: right; font-size: 12px; }

/* Zoom controls */
.zoom-group {
  display: flex;
  align-items: center;
  gap: 3px;
  flex-shrink: 0;
}
.zoom-btn {
  width: 26px; height: 26px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg-3);
  color: var(--fg);
  font-size: 14px;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
}
.zoom-btn:hover { border-color: var(--fg-dim); }
#zoom-display {
  min-width: 38px; text-align: center; font-size: 11px;
  color: var(--fg-dim); white-space: nowrap;
}

/* Action buttons */
.action-group {
  display: flex;
  gap: 4px;
  margin-left: auto;
  flex-shrink: 0;
}

.action-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  height: 30px;
  border: 1px solid var(--border);
  border-radius: 5px;
  background: var(--bg-3);
  color: var(--fg);
  font-size: 12px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.1s, border-color 0.1s;
}
.action-btn:hover { background: var(--bg-1); border-color: var(--fg-dim); }
.action-btn:disabled { opacity: 0.35; cursor: default; }
.action-btn.danger:hover { border-color: #f87171; color: #f87171; }

input[type="file"].hidden-file { position: absolute; width: 0; height: 0; opacity: 0; pointer-events: none; }

/* ── Left tool panel ───────────────────────── */

.left-panel {
  width: 48px;
  background: var(--bg-2);
  border-right: 1px solid var(--border);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 6px 4px;
  overflow-y: auto;
  overflow-x: hidden;
  gap: 0;
}

/* ── Main body (canvas area + layer panel) ───── */

.paint-body {
  flex: 1;
  display: flex;
  overflow: hidden;
}

/* ── Canvas area ────────────────────────────── */

#canvas-area {
  flex: 1;
  overflow: auto;
  background: var(--bg-3);
  display: flex;
  align-items: flex-start;
  justify-content: flex-start;
  position: relative;
}

.canvas-stack {
  position: relative;
  flex-shrink: 0;
  transform-origin: 0 0;
}

.layer-canvas, #main-canvas {
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  pointer-events: none;
}

#overlay-canvas {
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  cursor: crosshair;
  touch-action: none;
}

/* Text input overlay */
#text-input {
  display: none;
  position: absolute;
  background: transparent;
  border: 1px dashed rgba(255,255,255,0.5);
  outline: none;
  padding: 2px 4px;
  min-width: 80px;
  min-height: 1.4em;
  color: #000;
  font-family: sans-serif;
  resize: none;
  overflow: hidden;
  z-index: 10;
  line-height: 1.2;
}

/* ── Panel resize handle ─────────────────────── */

.panel-resize-handle {
  width: 5px;
  flex-shrink: 0;
  cursor: col-resize;
  background: transparent;
  transition: background 0.15s;
  z-index: 5;
  /* Widen the hit target without affecting layout */
  position: relative;
}
.panel-resize-handle::before {
  content: '';
  position: absolute;
  inset: 0 -4px; /* 4px extra hit area on each side */
}
.panel-resize-handle:hover,
.panel-resize-handle.dragging {
  background: rgba(148, 163, 184, 0.3);
}
.panel-resize-handle.dragging {
  background: rgba(244, 114, 182, 0.35);
}

/* ── Right panel (always visible) ───────────── */

.right-panel {
  width: var(--layer-panel-w);
  background: var(--bg-2);
  border-left: 1px solid var(--border);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

/* Accordion sections */
.panel-section {
  display: flex;
  flex-direction: column;
  border-bottom: 1px solid var(--border);
  min-height: 0;
}

.panel-section.expanded { flex: 1; }

.panel-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 7px 10px;
  cursor: pointer;
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--fg-dim);
  text-transform: uppercase;
  flex-shrink: 0;
  user-select: none;
}
.panel-section-header:hover { color: var(--fg); }

.panel-chevron {
  font-size: 10px;
  transition: transform 0.15s;
  color: var(--fg-dim);
}
.panel-section.collapsed .panel-chevron { transform: rotate(-90deg); }

.panel-section-body {
  overflow-y: auto;
  flex: 1;
  min-height: 0;
}
.panel-section.collapsed .panel-section-body { display: none; }

/* Layers inside panel */
#layer-list-container { padding: 6px; }

.layer-list { display: flex; flex-direction: column; gap: 3px; }

.layer-row {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 5px;
  border: 1px solid transparent;
  border-radius: 5px;
  cursor: pointer;
  transition: background 0.1s;
  min-width: 0;
}
.layer-row:hover { background: var(--bg-3); }
.layer-row.active { border-color: var(--accent); background: rgba(244,114,182,0.08); }

.layer-vis-btn {
  background: none; border: none; cursor: pointer;
  font-size: 13px; padding: 0; flex-shrink: 0; color: var(--fg);
}

.layer-thumb {
  flex-shrink: 0;
  border: 1px solid var(--border);
  border-radius: 2px;
  image-rendering: pixelated;
}

.layer-name-wrap {
  flex: 1; min-width: 0;
  display: flex; flex-direction: column; gap: 2px;
}
.layer-name {
  font-size: 12px; color: var(--fg);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.layer-opacity {
  width: 100%; height: 3px; accent-color: var(--accent); cursor: pointer;
}

.layer-move-wrap {
  display: flex; gap: 2px; flex-shrink: 0;
}
.layer-move-btn, .layer-del-btn {
  width: 18px; height: 18px;
  background: none; border: 1px solid var(--border); border-radius: 3px;
  color: var(--fg-dim); cursor: pointer; font-size: 10px;
  display: flex; align-items: center; justify-content: center;
}
.layer-move-btn:hover { color: var(--fg); border-color: var(--fg-dim); }
.layer-del-btn:hover { color: #f87171; border-color: #f87171; }
.layer-del-btn:disabled, .layer-move-btn:disabled { opacity: 0.3; cursor: default; }

.layer-panel-footer {
  padding: 6px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex-shrink: 0;
}
.layer-add-btn {
  width: 100%; padding: 5px; background: var(--bg-3);
  border: 1px solid var(--border); border-radius: 4px;
  color: var(--fg); cursor: pointer; font-size: 12px;
}
.layer-add-btn:hover { border-color: var(--accent); color: var(--accent); }

/* History panel */
.history-list {
  display: flex;
  flex-direction: column;
  padding: 4px 6px;
  gap: 1px;
}

.history-item {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 4px 7px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
  color: var(--fg-dim);
  transition: background 0.1s;
}
.history-item:hover { background: var(--bg-3); color: var(--fg); }
.history-item.current { color: var(--fg); font-weight: 600; }
.history-item.future { opacity: 0.35; }

.history-icon { font-size: 13px; flex-shrink: 0; }

/* ── Palette bar ────────────────────────────── */

.palette-bar-outer {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 10px;
  height: var(--palette-h);
  background: var(--bg-2);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  overflow: hidden;
}

#palette-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  flex: 1;
  min-width: 0;
}

.fb-wrap {
  position: relative; width: 44px; height: 34px; flex-shrink: 0;
}
.fb-swatch {
  position: absolute; width: 26px; height: 26px;
  border: 2px solid #fff; border-radius: 3px; cursor: pointer;
  transition: transform 0.1s;
}
.bg-swatch { bottom: 0; right: 0; border-color: var(--fg-dim); z-index: 1; }
.fg-swatch { top: 0; left: 0; border-color: #fff; z-index: 2; }
.fg-swatch:hover, .bg-swatch:hover { transform: scale(1.1); }

.hidden-color-input {
  position: absolute; width: 0; height: 0; opacity: 0; pointer-events: none;
}

.palette-sep { width: 1px; height: 28px; background: var(--border); flex-shrink: 0; }

.swatch-grid {
  display: flex; flex-wrap: wrap; gap: 2px; flex: 1; min-width: 0;
}
.color-swatch {
  width: 20px; height: 20px;
  border: 1px solid rgba(255,255,255,0.1); border-radius: 2px;
  cursor: pointer; transition: transform 0.1s, border-color 0.1s; flex-shrink: 0;
}
.color-swatch:hover {
  transform: scale(1.3); border-color: #fff; z-index: 1; position: relative;
}

.color-history {
  display: flex; gap: 2px; flex-shrink: 0;
}
.history-swatch {
  width: 18px; height: 18px;
  border: 1px solid rgba(255,255,255,0.15); border-radius: 2px;
  cursor: pointer; transition: transform 0.1s, border-color 0.1s;
}
.history-swatch:hover { transform: scale(1.3); border-color: #fff; position: relative; z-index: 1; }

.status-bar {
  display: flex; align-items: center; gap: 8px; flex-shrink: 0;
  color: var(--fg-dim); font-size: 12px; white-space: nowrap; margin-left: auto;
}

/* ── Resize modal ───────────────────────────── */

.modal {
  position: fixed; inset: 0; z-index: 1000;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(4px);
}
.modal.hidden { display: none; }

.modal-box {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 24px;
  min-width: 280px;
  display: flex; flex-direction: column; gap: 16px;
}
.modal-box h2 { font-size: 16px; font-weight: 600; }
.modal-row {
  display: flex; align-items: center; gap: 10px;
}
.modal-row label { width: 60px; color: var(--fg-dim); font-size: 13px; }
.modal-row input[type="number"] {
  flex: 1; padding: 6px 8px;
  background: var(--bg-3); border: 1px solid var(--border); border-radius: 5px;
  color: var(--fg); font-size: 13px;
}
.modal-buttons { display: flex; gap: 8px; justify-content: flex-end; }
.modal-btn {
  padding: 6px 16px; border-radius: 5px; border: 1px solid var(--border);
  cursor: pointer; font-size: 13px;
}
.modal-btn.primary {
  background: var(--accent); border-color: var(--accent); color: #fff;
}
.modal-btn.secondary { background: var(--bg-3); color: var(--fg); }
.modal-btn:hover { opacity: 0.85; }

/* ── Back link ──────────────────────────────── */
.back-to-portfolio {
  display: flex; align-items: center; gap: 4px;
  color: var(--fg-dim); text-decoration: none;
  font-size: 12px; padding: 4px 8px;
  border: 1px solid var(--border); border-radius: 5px;
  transition: color 0.1s, border-color 0.1s; flex-shrink: 0;
}
.back-to-portfolio:hover { color: var(--fg); border-color: var(--fg-dim); }

/* ── Mobile ─────────────────────────────────── */
@media (max-width: 600px) {
  .paint-header { height: auto; padding: 6px 8px 6px 72px; gap: 4px; }
  #brush-size { width: 60px; }
  .action-btn span:not(.btn-icon) { display: none; }
  .swatch-grid { gap: 1px; }
  .color-swatch { width: 16px; height: 16px; }
  .left-panel { width: 40px; padding: 4px 2px; }
  .tool-btn { width: 32px; height: 32px; font-size: 14px; }
  .right-panel { display: none; }
}