:root {
  --bg: #0f172a;
  /* slate-900 */
  --panel: #111827;
  /* gray-900 */
  --panel-border: #1f2937;
  /* gray-800 */
  --text: #e5e7eb;
  /* gray-200 */
  --muted: #94a3b8;
  /* slate-400 */
  --accent: #22c55e;
  /* green-500 */
  --accent-2: #3b82f6;
  /* blue-500 */
  --danger: #ef4444;
  /* red-500 */
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  --radius: 12px;
  --gap: 20px;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  padding: 24px;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  background: radial-gradient(1200px 800px at 20% -20%, #1e293b 0%, var(--bg) 55%);
  color: var(--text);
  display: grid;
  grid-template-columns: 1fr 320px;
  grid-template-rows: 1fr auto;
  gap: var(--gap);
  align-items: start;
  height: 100vh;
  overflow: hidden;
}

main {
  grid-row: 1;
  grid-column: 1;
  overflow: auto;
}

aside {
  grid-row: 1;
  grid-column: 2;
}

#generationText {
  grid-column: 1 / -1;
  margin: 0 0 8px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

main {
  grid-row: 1;
  grid-column: 1;
  overflow: auto;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.02));
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  padding: 16px;
  padding-bottom: 0;
  box-shadow: var(--shadow);
}

canvas {
  display: block;
  background: #0b1220;
  border-radius: 10px;
  outline: 1px solid #1f2937;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.05), 0 12px 24px rgba(2, 6, 23, 0.35);
}

aside {
  grid-row: 1;
  grid-column: 2;
  position: sticky;
  top: 24px;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

footer {
  grid-column: 1 / -1;
  grid-row: 2;
  margin-top: 0;
  font-size: 12px;
  color: var(--muted);
  text-align: center;
}

.control-label {
  font-size: 12px;
  color: var(--muted);
}

select {
  width: 100%;
  border-radius: 10px;
  padding: 10px 12px;
  background: #0b1220;
  color: var(--text);
  outline: 1px solid #1f2937;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
}

/* Range slider styling */
input[type="range"] {
  appearance: none;
  width: 100%;
  height: 32px;
  background: transparent;
}

input[type="range"]:focus {
  outline: none;
}

input[type="range"]:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* Track */
input[type="range"]::-webkit-slider-runnable-track {
  height: 6px;
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  border-radius: 999px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.08);
}

input[type="range"]::-moz-range-track {
  height: 6px;
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  border-radius: 999px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.08);
}

/* Thumb */
input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  -webkit-appearance: none;
  margin-top: -7px;
  /* center on track */
  width: 20px;
  height: 20px;
  background: #0b1220;
  border-radius: 50%;
  outline: 2px solid #1f2937;
  box-shadow: 0 2px 6px rgba(2, 6, 23, 0.45);
}

input[type="range"]::-moz-range-thumb {
  width: 20px;
  height: 20px;
  background: #0b1220;
  border-radius: 50%;
  outline: 2px solid #1f2937;
  box-shadow: 0 2px 6px rgba(2, 6, 23, 0.45);
}

button {
  appearance: none;
  border: 0;
  border-radius: 10px;
  padding: 12px 16px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text);
  background: #0b1220;
  outline: 1px solid #1f2937;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06), 0 6px 16px rgba(2, 6, 23, 0.35);
  transition: transform 120ms ease, box-shadow 200ms ease, outline-color 180ms ease, background 200ms ease;
  cursor: pointer;
}

button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(2, 6, 23, 0.45);
}

button:active {
  transform: translateY(0);
  box-shadow: 0 6px 12px rgba(2, 6, 23, 0.35);
}

button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
  box-shadow: 0 6px 16px rgba(2, 6, 23, 0.35);
}

/* Variants by ID for now; scalable as more buttons added */
#toggleBtn {
  background: linear-gradient(180deg, rgba(34, 197, 94, 0.15), rgba(34, 197, 94, 0.08));
  outline-color: rgba(34, 197, 94, 0.45);
}

#toggleBtn:hover {
  background: linear-gradient(180deg, rgba(34, 197, 94, 0.22), rgba(34, 197, 94, 0.14));
}

#clearBtn {
  background: linear-gradient(180deg, rgba(239, 68, 68, 0.15), rgba(239, 68, 68, 0.08));
  outline-color: rgba(239, 68, 68, 0.45);
}

#clearBtn:hover {
  background: linear-gradient(180deg, rgba(239, 68, 68, 0.22), rgba(239, 68, 68, 0.14));
}

#randomBtn {
  background: linear-gradient(180deg, rgba(59, 130, 246, 0.15), rgba(59, 130, 246, 0.08));
  outline-color: rgba(59, 130, 246, 0.45);
}

#randomBtn:hover {
  background: linear-gradient(180deg, rgba(59, 130, 246, 0.22), rgba(59, 130, 246, 0.14));
}

/* Allow future buttons to flow nicely */
aside {
  grid-auto-rows: min-content;
}

/* Responsive: stack on narrow screens */
@media (max-width: 820px) {
  body {
    grid-template-columns: 1fr;
  }

  aside {
    position: static;
  }
}