:root {
  --paper: #f6f1e7;
  --paper-raised: #fffbf3;
  --paper-sunken: #ece4d3;
  --ink: #1c1a17;
  --ink-dim: #6b6255;
  --ink-faint: #a89d8a;
  --line: #d8cdb6;
  --line-soft: #e6dcc7;
  --rust: #b5502e;
  --rust-dim: #8a3c22;
  --focus: #2f6fb0;
  --mono: "SFMono-Regular", "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --ui: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
}

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

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

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--ui);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(28,26,23,0.05) 1px, transparent 0);
  background-size: 22px 22px;
}

a { color: var(--rust-dim); }

button, input, select, textarea { font-family: inherit; font-size: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

.topbar {
  padding: 28px 20px 10px;
  max-width: 1180px;
  margin: 0 auto;
}
.brand {
  font-family: var(--mono);
  font-weight: 700;
  font-size: 26px;
  letter-spacing: -0.02em;
}
.brand::before { content: "\2724  "; color: var(--rust); }
.tag {
  margin: 6px 0 0;
  color: var(--ink-dim);
  max-width: 62ch;
}

.layout {
  max-width: 1180px;
  margin: 0 auto;
  padding: 8px 20px 40px;
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr) 220px;
  gap: 16px;
  align-items: start;
}

.panel {
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px;
  box-shadow: 0 1px 0 rgba(28,26,23,0.03);
}
.panel h2 {
  margin: 0 0 12px;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-dim);
  font-weight: 700;
}

/* ---- source panel ---- */

.dropzone {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  text-align: center;
  border: 1.5px dashed var(--line);
  border-radius: 8px;
  padding: 18px 10px;
  cursor: pointer;
  color: var(--ink-dim);
  transition: border-color .15s, background .15s;
  margin-bottom: 12px;
}
.dropzone:hover, .dropzone:focus-visible { border-color: var(--rust); color: var(--ink); }
.dropzone.dragover { border-color: var(--rust); background: rgba(181,80,46,0.06); color: var(--ink); }
.dz-icon { font-size: 20px; color: var(--rust); }
.dz-text { font-size: 12.5px; }

.presets-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 16px;
}
.preset-btn {
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 999px;
  padding: 5px 11px;
  font-size: 12px;
  cursor: pointer;
  transition: background .12s, border-color .12s;
}
.preset-btn:hover { border-color: var(--rust); }
.preset-btn:active { background: var(--paper-sunken); }

.field-group { display: flex; flex-direction: column; gap: 10px; margin-bottom: 14px; }
.field { margin-bottom: 14px; }
.field:last-child { margin-bottom: 0; }
.field-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}
.field-head label { font-size: 12.5px; color: var(--ink-dim); }
.field-val { font-family: var(--mono); font-size: 12px; color: var(--ink); }

input[type="range"] {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 4px;
  background: var(--line);
  border-radius: 2px;
  outline-offset: 4px;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 15px; height: 15px;
  border-radius: 50%;
  background: var(--rust);
  border: 2px solid var(--paper-raised);
  box-shadow: 0 0 0 1px var(--rust);
  cursor: pointer;
  margin-top: -1px;
}
input[type="range"]::-moz-range-thumb {
  width: 13px; height: 13px;
  border-radius: 50%;
  background: var(--rust);
  border: 2px solid var(--paper-raised);
  box-shadow: 0 0 0 1px var(--rust);
  cursor: pointer;
}
input[type="range"]:disabled { opacity: 0.4; }

select, .custom-ramp-input {
  width: 100%;
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 6px;
  padding: 7px 8px;
  margin-top: 2px;
}
.custom-ramp-input { font-family: var(--mono); margin-top: 8px; }

.switch-row { display: flex; gap: 14px; margin-bottom: 14px; flex-wrap: wrap; }
.switch {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  cursor: pointer;
  font-size: 12.5px;
  color: var(--ink-dim);
  user-select: none;
}
.switch input { accent-color: var(--rust); width: 15px; height: 15px; }
.switch input:checked ~ span { color: var(--ink); }

.field-color { display: flex; align-items: center; gap: 8px; }
.field-color label { font-size: 12px; color: var(--ink-dim); }
input[type="color"] {
  width: 32px; height: 26px;
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 2px;
  background: var(--paper);
  cursor: pointer;
}

.btn {
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 7px;
  padding: 8px 12px;
  font-size: 13px;
  cursor: pointer;
  transition: background .12s, border-color .12s, transform .06s;
}
.btn:hover { border-color: var(--rust); }
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: var(--rust);
  border-color: var(--rust);
  color: #fff8f0;
  width: 100%;
  font-weight: 600;
  display: flex;
  justify-content: center;
  gap: 6px;
  align-items: center;
}
.btn-primary:hover { background: var(--rust-dim); border-color: var(--rust-dim); }
.btn-primary kbd { background: rgba(255,255,255,0.18); color: inherit; border: none; }
.btn:disabled { opacity: 0.5; cursor: default; transform: none; }

.status-line {
  margin: 8px 0 0;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-dim);
  text-align: center;
  min-height: 1.4em;
}

kbd {
  font-family: var(--mono);
  font-size: 11px;
  background: var(--paper-sunken);
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 1px 5px;
}

/* ---- stage panel ---- */

.panel-stage { padding: 12px; display: flex; flex-direction: column; min-width: 0; }

.stage-toolbar {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  padding: 4px 4px 12px;
  border-bottom: 1px solid var(--line-soft);
  margin-bottom: 10px;
}

.tool-group { display: flex; gap: 4px; background: var(--paper-sunken); border-radius: 8px; padding: 3px; }
.tool-btn {
  border: none;
  background: transparent;
  border-radius: 6px;
  padding: 6px 10px;
  cursor: pointer;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 12.5px;
  color: var(--ink-dim);
  display: flex;
  align-items: center;
  gap: 6px;
}
.tool-btn span { font-family: var(--ui); font-weight: 500; text-transform: lowercase; }
.tool-btn.is-active { background: var(--paper-raised); color: var(--rust); box-shadow: 0 1px 2px rgba(28,26,23,0.12); }
.tool-btn:hover:not(.is-active) { color: var(--ink); }

.brush-controls { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.brush-chars { display: flex; gap: 3px; }
.brush-char-btn {
  width: 26px; height: 26px;
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 5px;
  cursor: pointer;
  font-family: var(--mono);
  font-size: 13px;
  display: flex; align-items: center; justify-content: center;
}
.brush-char-btn.is-active { border-color: var(--rust); background: rgba(181,80,46,0.1); color: var(--rust); }
.brush-custom-char {
  width: 34px; height: 26px;
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 5px;
  background: var(--paper);
  font-family: var(--mono);
}
.brush-size-label { font-size: 12px; color: var(--ink-dim); display: flex; align-items: center; gap: 6px; }
.brush-size-label input { width: 70px; }

.history-controls { display: flex; gap: 4px; margin-left: auto; }
.icon-btn {
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 6px;
  width: 30px; height: 28px;
  cursor: pointer;
  font-size: 14px;
  display: flex; align-items: center; justify-content: center;
}
.icon-btn#resetBtn { width: auto; padding: 0 10px; font-size: 11.5px; font-family: var(--mono); }
.icon-btn:hover:not(:disabled) { border-color: var(--rust); color: var(--rust); }
.icon-btn:disabled { opacity: 0.35; cursor: default; }

.zoom-label { font-size: 12px; color: var(--ink-dim); display: flex; align-items: center; gap: 6px; margin-left: auto; }
.zoom-label input { width: 90px; }
.history-controls + .zoom-label { margin-left: 0; }

.stage-wrap { position: relative; flex: 1; min-height: 260px; }
.stage-scroll {
  overflow: auto;
  max-height: 62vh;
  border: 1px solid var(--line-soft);
  border-radius: 8px;
  background: repeating-conic-gradient(var(--paper-sunken) 0% 25%, var(--paper) 0% 50%) 0 0 / 16px 16px;
  display: flex;
  padding: 10px;
}
.canvas-holder { position: relative; margin: auto; flex: none; box-shadow: 0 2px 10px rgba(28,26,23,0.15); }
.canvas-holder canvas { position: absolute; inset: 0; display: block; }
#overlayCanvas { cursor: crosshair; }

.empty-hint {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink-faint);
  font-size: 13px;
  text-align: center;
  padding: 0 30px;
  pointer-events: none;
}
.empty-hint[hidden] { display: none; }

.shortcuts-line {
  margin: 10px 4px 0;
  font-size: 11.5px;
  color: var(--ink-faint);
  text-align: center;
}
.shortcuts-line kbd { margin: 0 1px; }

/* ---- export panel ---- */

.export-grid { display: flex; flex-direction: column; gap: 8px; margin-bottom: 12px; }
.switch-transparent { margin-bottom: 8px; }
.copy-feedback {
  min-height: 1.4em;
  font-size: 12px;
  color: var(--rust-dim);
  margin: 0;
}

.footer {
  text-align: center;
  padding: 20px 0 36px;
  font-size: 13px;
  color: var(--ink-dim);
}
.footer a { text-decoration: none; }
.footer a:hover { text-decoration: underline; }

@media (max-width: 980px) {
  .layout { grid-template-columns: 1fr; }
  .panel-stage { order: -1; }
  .stage-scroll { max-height: 48vh; }
}

@media (max-width: 480px) {
  .stage-toolbar { gap: 8px; }
  .zoom-label, .history-controls { margin-left: 0; }
}