:root {
  --bs-body-bg: #1a1d21;
  --bs-card-bg: #23272d;
  --bs-card-border: #353a42;
  --bs-stage-bg: #3a4049;
  --bs-stage-border: #4a515b;
  --bs-input-bg: #16191d;
  --bs-input-border: #3d434c;
  --bs-text: #e9ecef;
  --bs-text-muted: #9aa3ad;
  --bs-text-dim: #6c757d;
  --bs-primary: #0d6efd;
  --bs-primary-hover: #0b5ed7;
  --bs-primary-ring: rgba(13, 110, 253, 0.25);
  --bs-radius: 6px;
}

* { box-sizing: border-box; }

body {
  font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
  background: var(--bs-body-bg);
  color: var(--bs-text);
  margin: 0;
  padding: 32px 20px;
  min-height: 100vh;
  line-height: 1.5;
}

.container { max-width: 1200px; margin: 0 auto; }
.docs { max-width: 800px; margin: 0 auto; }

/* Header */
header {
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--bs-card-border);
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
}
header h1 {
  margin: 0 0 4px;
  font-size: 1.6rem;
  font-weight: 600;
}
header p {
  margin: 0;
  color: var(--bs-text-muted);
  font-size: 0.9rem;
}

/* Links & Buttons */
a { color: var(--bs-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  font-size: 0.85rem;
  font-weight: 500;
  color: #fff;
  background: var(--bs-primary);
  border: 1px solid var(--bs-primary);
  border-radius: var(--bs-radius);
  text-decoration: none;
  transition: background 0.12s, border-color 0.12s;
  white-space: nowrap;
  cursor: pointer;
}
.btn:hover {
  background: var(--bs-primary-hover);
  border-color: var(--bs-primary-hover);
  text-decoration: none;
}

.back-link {
  color: var(--bs-text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  padding: 6px 12px;
  border: 1px solid var(--bs-card-border);
  border-radius: var(--bs-radius);
  transition: all 0.12s;
  white-space: nowrap;
}
.back-link:hover { color: var(--bs-text); border-color: var(--bs-text-muted); text-decoration: none; }

/* Typography */
h2 {
  margin: 36px 0 12px;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--bs-text);
}
h2:first-of-type { margin-top: 24px; }

/* Layout */
.grid {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 16px;
  align-items: start;
}
@media (max-width: 880px) { .grid { grid-template-columns: 1fr; } }

/* Cards */
.card {
  background: var(--bs-card-bg);
  border: 1px solid var(--bs-card-border);
  border-radius: var(--bs-radius);
  overflow: hidden;
  margin-bottom: 16px;
}
.card-header {
  padding: 10px 16px;
  background: rgba(255, 255, 255, 0.02);
  border-bottom: 1px solid var(--bs-card-border);
  font-size: 0.85rem;
  font-weight: 600;
}
.card-body { padding: 16px; }

/* Preview stage */
.card.preview {
  background: var(--bs-stage-bg);
  border-color: var(--bs-stage-border);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.35);
  position: relative;
}
.card.preview::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--bs-primary);
}
.card.preview .card-header {
  background: rgba(13, 110, 253, 0.08);
  border-bottom-color: var(--bs-stage-border);
}
.card.preview .card-body {
  background-image:
    radial-gradient(circle, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 14px 14px;
}

/* Form controls */
.mb-3 { margin-bottom: 12px; }
.mb-3:last-child { margin-bottom: 0; }
.mb-3.hidden { display: none; }

.form-label {
  display: block;
  margin-bottom: 4px;
  font-size: 0.82rem;
  font-weight: 500;
}
.form-label .opt {
  font-weight: 400;
  color: var(--bs-text-dim);
  margin-left: 4px;
}

.form-control,
.form-select {
  display: block;
  width: 100%;
  padding: 7px 11px;
  font-size: 0.875rem;
  font-family: inherit;
  line-height: 1.5;
  color: var(--bs-text);
  background: var(--bs-input-bg);
  border: 1px solid var(--bs-input-border);
  border-radius: var(--bs-radius);
  transition: border-color 0.12s, box-shadow 0.12s;
}
.form-control::placeholder { color: var(--bs-text-dim); }
.form-control:focus,
.form-select:focus {
  outline: 0;
  border-color: #86b7fe;
  box-shadow: 0 0 0 0.2rem var(--bs-primary-ring);
}

textarea.form-control {
  font-family: 'Cascadia Code', 'Consolas', monospace;
  font-size: 0.83rem;
  resize: vertical;
  min-height: 110px;
}

.form-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath fill='none' stroke='%239aa3ad' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
  background-size: 14px;
  padding-right: 32px;
}
.form-select option { background: var(--bs-input-bg); color: var(--bs-text); }