/* ========================================
   dither-bitmap - minimalist dark theme
   ======================================== */

:root {
  --bg: #0a0a0a;
  --bg-surface: #111111;
  --bg-hover: #1a1a1a;
  --border: #2a2a2a;
  --border-hover: #444444;
  --text: #e0e0e0;
  --text-dim: #666666;
  --text-muted: #444444;
  --accent: #ffffff;
  --radius: 4px;
  --gap: 24px;
  --max-width: 1100px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', 'JetBrains Mono', monospace;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 32px 20px;
}

/* Header / Logo */
.header {
  margin-bottom: 40px;
  text-align: center;
}

.logo-canvas {
  height: 40px;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

/* Main layout */
.main {
  display: flex;
  gap: var(--gap);
  width: 100%;
  max-width: var(--max-width);
  margin-bottom: 32px;
}

.panel {
  flex: 1;
  min-width: 0;
}

/* Upload zone */
.upload-zone {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 360px;
  height: 100%;
  border: 1.5px dashed var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 0.2s, background-color 0.2s;
  overflow: hidden;
  position: relative;
  background: var(--bg-surface);
}

.upload-zone:hover,
.upload-zone:focus-visible {
  border-color: var(--border-hover);
  background: var(--bg-hover);
}

.upload-zone.dragover {
  border-color: var(--accent);
  background: var(--bg-hover);
}

.upload-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 24px;
}

.upload-icon {
  width: 36px;
  height: 36px;
  color: var(--text-dim);
}

.upload-text {
  font-size: 0.85rem;
  color: var(--text-dim);
}

.upload-hint {
  font-size: 0.7rem;
  color: var(--text-muted);
}

/* Privacy note */
.privacy-note {
  font-size: 0.65rem;
  color: var(--text-muted);
  text-align: left;
  margin-top: 8px;
  letter-spacing: 0.02em;
}

/* Output container */
.output-container {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 360px;
  height: 100%;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-surface);
}

/* Output placeholder */
.output-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.output-placeholder-text {
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* Canvas images */
.image-canvas {
  max-width: 100%;
  max-height: 500px;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

.hidden {
  display: none;
}

/* Fade transition for processing feedback */
.image-canvas {
  transition: opacity 0.3s ease;
}

.faded {
  opacity: 0.15;
}

/* Toggles */
.toggles {
  display: flex;
  gap: 32px;
  width: 100%;
  max-width: var(--max-width);
  margin-bottom: 20px;
  justify-content: center;
}

.toggle-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.toggle-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-dim);
}

.toggle-buttons {
  display: flex;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.toggle-btn {
  padding: 6px 16px;
  font-family: inherit;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  background: var(--bg-surface);
  color: var(--text-dim);
  border: none;
  cursor: pointer;
  transition: background-color 0.15s, color 0.15s;
}

.toggle-btn:not(:last-child) {
  border-right: 1px solid var(--border);
}

.toggle-btn:hover:not(:disabled) {
  background: var(--bg-hover);
}

.toggle-btn.active {
  background: var(--accent);
  color: var(--bg);
}

.toggle-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.toggle-btn.active:disabled {
  opacity: 0.3;
}

/* Controls */
.controls {
  display: flex;
  gap: 32px;
  width: 100%;
  max-width: var(--max-width);
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.slider-group {
  flex: 1;
  min-width: 200px;
}

.slider-group label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 8px;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.slider-label {
  color: var(--text-dim);
}

.slider-value {
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

/* Custom range slider */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
  transition: opacity 0.2s;
}

input[type="range"]:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
}

input[type="range"]:disabled::-webkit-slider-thumb {
  cursor: not-allowed;
}

input[type="range"]:disabled::-moz-range-thumb {
  cursor: not-allowed;
}

/* Actions */
.actions {
  display: flex;
  gap: 12px;
  width: 100%;
  max-width: var(--max-width);
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  font-family: inherit;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-surface);
  color: var(--text);
  cursor: pointer;
  transition: border-color 0.2s, background-color 0.2s;
}

.btn:hover:not(:disabled) {
  border-color: var(--accent);
  background: var(--bg-hover);
}

.btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.btn-icon {
  width: 16px;
  height: 16px;
}

/* Responsive */
@media (max-width: 700px) {
  body {
    padding: 20px 12px;
  }

  .main {
    flex-direction: column;
    gap: 16px;
  }

  .upload-zone,
  .output-container {
    min-height: 260px;
  }

  .controls {
    flex-direction: column;
    gap: 16px;
  }

  .slider-group {
    min-width: unset;
  }
}