/* Reset and base */
* { box-sizing: border-box; }
:root {
  --bg: #161616;
  --fg: #e6e3dd;
  --muted: #8a8780;
  --accent: #6ea8fe;
  --accent-hover: #91bfff;
  --border: #2c2c2c;
  --field-bg: #1f1f1f;
  --panel-bg: #1a1a1a;
}
html { color-scheme: dark; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--fg);
  margin: 0;
  padding: 0;
  line-height: 1.5;
}

header, main, footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
}

header h1 {
  margin: 1rem 0 0.25rem;
  font-size: 1.7rem;
}
.subtitle {
  color: var(--muted);
  font-size: 0.95rem;
  margin: 0 0 1rem;
}
.subtitle a { color: var(--accent); }

/* Form */
fieldset {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.75rem 1rem 1rem;
  margin: 0 0 1rem;
  background: var(--panel-bg);
}
legend {
  font-weight: 600;
  padding: 0 0.5rem;
}
label {
  display: block;
  margin: 0.5rem 0;
  font-size: 0.9rem;
  font-weight: 500;
}
.hint {
  display: block;
  font-weight: 400;
  color: var(--muted);
  font-size: 0.85rem;
  margin: 0.2rem 0 0.3rem;
}
.hint code {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.85rem;
  background: rgba(255, 255, 255, 0.07);
  padding: 0 0.25rem;
  border-radius: 3px;
}
input[type="number"],
select {
  display: block;
  width: 100%;
  padding: 0.45rem 0.6rem;
  margin-top: 0.25rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--field-bg);
  color: var(--fg);
  font-size: 1rem;
  font-family: inherit;
}
input[type="number"]:focus,
select:focus {
  outline: 2px solid var(--accent);
  outline-offset: -1px;
}

.actions {
  margin-top: 1rem;
}
button {
  display: block;
  width: 100%;
  padding: 0.7rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  background: var(--accent);
  color: #fff;
  border: 0;
  border-radius: 4px;
  cursor: pointer;
}
button:disabled {
  background: var(--muted);
  cursor: not-allowed;
}
button:not(:disabled):hover {
  filter: brightness(1.1);
}

.status {
  margin-top: 0.75rem;
  padding: 0.5rem 0.75rem;
  font-size: 0.9rem;
  border-radius: 4px;
  min-height: 1.5em;
}
.status.error {
  background: rgba(255, 82, 82, 0.15);
  color: #ff8888;
}
.status.info {
  background: rgba(82, 140, 255, 0.15);
  color: #8ab3ff;
}
.status.ok {
  background: rgba(82, 200, 120, 0.15);
  color: #8ad99e;
}

/* Output */
.output-section h2 {
  font-size: 1.2rem;
  margin: 1.5rem 0 0.5rem;
}
.muted {
  color: var(--muted);
  font-size: 0.9rem;
  margin: 0 0 0.75rem;
}
.downloads {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
}
.downloads li {
  margin: 0.25rem 0;
}
.downloads a {
  display: inline-block;
  padding: 0.4rem 0.7rem;
  background: var(--panel-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  text-decoration: none;
  color: var(--accent);
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.9rem;
}
.downloads a:hover {
  border-color: var(--accent);
  color: var(--accent-hover);
}

/* Preview canvas */
.preview-wrap {
  position: relative;
  margin: 0.25rem 0 0.5rem;
}
#preview {
  display: block;
  width: 100%;
  height: 420px;
  background: #0d0d0d;
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: grab;
}
#preview:active { cursor: grabbing; }
.preview-hint { margin-top: 0; }

.preview-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: 0.02em;
  background: rgba(13, 13, 13, 0.55);
  border-radius: 4px;
  transition: opacity 200ms ease;
}
.preview-overlay.hidden { opacity: 0; }

.preview-toggles {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin: 0.25rem 0 1rem;
  font-size: 0.9rem;
}
.preview-toggles .toggle {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 0.4rem;
  cursor: pointer;
  user-select: none;
  font-weight: 500;
  margin: 0;
  width: auto;
}
.toggle input[type="checkbox"] {
  margin: 0;
  accent-color: var(--accent);
}
.swatch {
  display: inline-block;
  width: 14px;
  height: 14px;
  border-radius: 3px;
  border: 1px solid var(--border);
}
.swatch-body { background: #b0b0b0; }
.swatch-rail { background: #d9882a; }

/* Units radio row */
.radio-row {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: center;
}
.radio-row .radio {
  display: inline-flex;
  flex-direction: row;
  align-items: center;
  gap: 0.4rem;
  margin: 0;
  cursor: pointer;
  user-select: none;
  font-weight: 500;
  width: auto;
}
.radio input[type="radio"] {
  margin: 0;
  accent-color: var(--accent);
}

.instructions {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
  font-size: 0.95rem;
}
.instructions li {
  margin: 0.3rem 0;
}

footer {
  border-top: 1px solid var(--border);
  margin-top: 2rem;
  padding-top: 1rem;
  padding-bottom: 1.5rem;
  font-size: 0.85rem;
  color: var(--muted);
}
footer a {
  color: var(--accent);
  text-decoration: none;
}
footer a:hover { text-decoration: underline; }