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

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #111;
  color: #f6f1e7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.bt-header {
  background: #241812;
  border-bottom: 2px solid #f2b46a;
}

.bt-header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1rem 1.25rem;
}

.bt-logo {
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-size: 0.85rem;
  color: #f2b46a;
}

.bt-header h1 {
  font-size: 1.6rem;
  margin-top: 0.3rem;
}

.bt-tagline {
  margin-top: 0.25rem;
  font-size: 0.95rem;
  color: #f0d8b6;
}

.bt-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  max-width: 1100px;
  margin: 0 auto;
  padding: 1rem 1.25rem 2rem;
  gap: 1rem;
}

.bt-controls {
  background: #1b1b1b;
  border-radius: 12px;
  padding: 1rem;
  border: 1px solid #333;
  display: grid;
  grid-template-columns: minmax(0, 2.2fr) minmax(0, 2.2fr) minmax(0, 1.6fr);
  gap: 1rem;
}

@media (max-width: 900px) {
  .bt-controls {
    grid-template-columns: 1fr;
  }
}

.file-label {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  font-size: 0.9rem;
  color: #f0d8b6;
}

.file-label input[type="file"] {
  background: #111;
  border-radius: 6px;
  border: 1px solid #444;
  padding: 0.4rem;
  color: #f6f1e7;
}

.mode-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.mode-btn {
  flex: 1 1 auto;
  padding: 0.45rem 0.75rem;
  border-radius: 999px;
  border: 1px solid #444;
  background: #151515;
  color: #f6f1e7;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}

.mode-btn:hover {
  border-color: #f2b46a;
}

.mode-btn.active {
  background: #f2b46a;
  color: #1b120b;
  border-color: #f2b46a;
  transform: translateY(-1px);
}

.sliders {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.slider-group {
  font-size: 0.85rem;
  color: #f0d8b6;
}

.slider-group input[type="range"] {
  width: 100%;
}

#pencil-controls,
#vintage-controls {
  display: none; /* default visible: Notan only when chosen */
}

.download-btn {
  margin-top: 0.3rem;
  grid-column: 1 / -1;
  justify-self: flex-start;
  padding: 0.5rem 1.2rem;
  border-radius: 999px;
  border: none;
  background: #f2b46a;
  color: #1b120b;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: opacity 0.15s ease, transform 0.1s ease;
}

.download-btn:disabled {
  opacity: 0.4;
  cursor: default;
}

.download-btn:not(:disabled):active {
  transform: translateY(1px);
}

.bt-canvas-wrap {
  background: #000;
  border-radius: 12px;
  border: 1px solid #333;
  padding: 0.5rem;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 260px;
}

#display-canvas {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  background: #222;
}

.bt-footer {
  border-top: 1px solid #333;
  padding: 0.75rem 1.25rem;
  font-size: 0.8rem;
  text-align: center;
  color: #a8977a;
}