.concepts-page {
  --concept-accent: var(--blue);
  --concept-soft: var(--blue-soft);
}

.concepts-hero {
  padding-bottom: clamp(2rem, 5vw, 4.5rem);
}

.concepts-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(18rem, 0.65fr);
  gap: clamp(2rem, 6vw, 6rem);
  align-items: end;
}

.concepts-hero h1 {
  max-width: 13ch;
  margin-bottom: 0;
}

.concepts-hero .lede {
  margin: 0;
}

.concepts-back {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  margin-bottom: 2rem;
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 700;
}

.concepts-back::before { content: "←"; }
.concepts-back:hover { color: var(--ink); }

.concepts-workspace-section {
  padding-top: 0;
}

.concept-selector {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.concept-choice,
.package-choice,
.option-card,
.counter-card {
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}

.concept-choice {
  min-height: 12.5rem;
  padding: 1.35rem;
  border-radius: var(--radius-lg);
  text-align: left;
  cursor: pointer;
}

.concept-choice:hover,
.package-choice:hover,
.option-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.concept-choice[aria-pressed="true"],
.package-choice[aria-pressed="true"],
.option-card[aria-pressed="true"] {
  background: linear-gradient(145deg, var(--surface-strong), var(--concept-soft));
  border-color: color-mix(in srgb, var(--concept-accent) 58%, var(--line));
  box-shadow: 0 0 0 2px var(--concept-soft), var(--shadow-sm);
}

.choice-index,
.config-step,
.summary-label,
.detail-card h3,
.pilot-card small {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.concept-choice strong {
  display: block;
  margin: 1.25rem 0 0.55rem;
  font-size: 1.1rem;
}

.concept-choice span:last-child {
  display: block;
  color: var(--muted);
  line-height: 1.55;
}

.config-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(18rem, 22rem);
  gap: 1.25rem;
  align-items: start;
}

.config-main,
.config-summary {
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  box-shadow: var(--shadow-lg);
}

.config-main { padding: clamp(1.35rem, 3vw, 2.5rem); }

.config-heading {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  align-items: flex-start;
  padding-bottom: 1.5rem;
  margin-bottom: 1.75rem;
  border-bottom: 1px solid var(--line);
}

.config-heading h2 { margin: 0.45rem 0 0; }

.config-price-from {
  flex: 0 0 auto;
  padding: 0.65rem 0.85rem;
  border-radius: 999px;
  background: var(--concept-soft);
  color: var(--ink);
  font-weight: 800;
}

.config-group + .config-group {
  padding-top: 2rem;
  margin-top: 2rem;
  border-top: 1px solid var(--line);
}

.config-step { margin-bottom: 0.85rem; }

.package-grid,
.option-grid,
.detail-grid {
  display: grid;
  gap: 0.75rem;
}

.package-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.option-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.detail-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 1.5rem; }

.package-choice,
.option-card {
  position: relative;
  padding: 1rem;
  border-radius: var(--radius-md);
  text-align: left;
  cursor: pointer;
}

.package-choice strong,
.option-card strong { display: block; }

.package-choice span,
.option-card span {
  display: block;
  margin-top: 0.35rem;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.45;
}

.package-choice b {
  display: block;
  margin-top: 1rem;
  color: var(--ink);
  font-size: 1.05rem;
}

.option-card[aria-pressed="true"]::after {
  content: "✓";
  position: absolute;
  top: 0.8rem;
  right: 0.8rem;
  color: var(--concept-accent);
  font-weight: 900;
}

.counter-card {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
  border-radius: var(--radius-md);
}

.counter-card p { margin: 0.35rem 0 0; color: var(--muted); font-size: 0.82rem; }

.counter-controls { display: flex; align-items: center; gap: 0.65rem; }

.counter-controls button {
  width: 2rem;
  height: 2rem;
  border: 1px solid var(--line-strong);
  border-radius: 0.55rem;
  color: var(--ink);
  background: var(--surface-strong);
  cursor: pointer;
}

.counter-controls output { min-width: 1.75rem; text-align: center; font-weight: 800; }

.details-toggle {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  color: var(--ink);
  background: var(--surface-strong);
  cursor: pointer;
  font-weight: 800;
}

.detail-card {
  padding: 1.15rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.detail-card ul { margin: 0.8rem 0 0; padding: 0; list-style: none; }
.detail-card li { position: relative; padding: 0.42rem 0 0.42rem 1.1rem; color: var(--muted); line-height: 1.5; }
.detail-card li::before { content: ""; position: absolute; left: 0; top: 0.95rem; width: 0.35rem; height: 0.35rem; border-radius: 50%; background: var(--concept-accent); }

.config-summary {
  position: sticky;
  top: 7.25rem;
  overflow: hidden;
}

.summary-top {
  padding: 1.4rem;
  color: #f7f5ef;
  background: linear-gradient(145deg, #121722, #222947);
}

.summary-top h3 { margin: 0.45rem 0 0; font-size: 1.15rem; color: inherit; }

.summary-lines { padding: 1.25rem 1.4rem; }

.summary-line {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.5rem 0;
  color: var(--muted);
  font-size: 0.86rem;
}

.summary-line strong { color: var(--ink); text-align: right; }

.summary-total {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1rem;
  margin-top: 0.7rem;
  border-top: 1px solid var(--line);
}

.summary-total strong { font-size: 1.45rem; }
.summary-note { margin: 0.8rem 0 0; color: var(--muted); font-size: 0.75rem; line-height: 1.5; }

.summary-actions { display: grid; gap: 0.6rem; padding: 0 1.4rem 1.4rem; }
.summary-actions .btn { width: 100%; justify-content: space-between; }

.pilot-card {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1.5rem;
  align-items: center;
  margin-top: 1.25rem;
  padding: clamp(1.25rem, 3vw, 2rem);
  border-radius: var(--radius-xl);
  color: #f7f5ef;
  background: linear-gradient(135deg, #111722, #25205b);
  box-shadow: var(--shadow-lg);
}

.pilot-card h2 { margin: 0.45rem 0; color: inherit; }
.pilot-card p { max-width: 54rem; margin: 0; color: rgba(247,245,239,.72); }
.pilot-price { text-align: right; }
.pilot-price strong { display: block; font-size: clamp(1.6rem, 4vw, 2.4rem); white-space: nowrap; }
.pilot-price span { color: rgba(247,245,239,.65); font-size: 0.78rem; }

.config-toast {
  position: fixed;
  z-index: 80;
  left: 50%;
  bottom: 1.5rem;
  transform: translateX(-50%);
  padding: 0.75rem 1rem;
  border-radius: 999px;
  color: #fff;
  background: #111722;
  box-shadow: var(--shadow-lg);
}

html[data-theme="dark"] .concept-choice,
html[data-theme="dark"] .package-choice,
html[data-theme="dark"] .option-card,
html[data-theme="dark"] .counter-card,
html[data-theme="dark"] .config-main,
html[data-theme="dark"] .config-summary,
html[data-theme="dark"] .detail-card,
html[data-theme="dark"] .details-toggle {
  background: var(--surface);
}

@media (max-width: 900px) {
  .concepts-hero-grid,
  .config-shell { grid-template-columns: 1fr; }
  .config-summary { position: static; }
}

@media (max-width: 700px) {
  .concept-selector,
  .package-grid,
  .option-grid,
  .detail-grid { grid-template-columns: 1fr; }
  .concept-choice { min-height: 0; }
  .config-heading,
  .pilot-card { grid-template-columns: 1fr; display: grid; }
  .pilot-price { text-align: left; }
}


/* Dark workspace surfaces keep hierarchy without muting inactive concepts. */
html[data-theme="dark"] .concepts-page { --concept-soft: rgba(123,108,255,.16); }
html[data-theme="dark"] :is(.concept-choice, .package-choice, .option-card, .counter-card, .config-main, .config-summary, .detail-card, .details-toggle) {
  color: var(--ink);
  background: rgba(18,24,34,.9);
  border-color: var(--line);
}
html[data-theme="dark"] :is(.concept-choice, .package-choice, .option-card):is(:hover, [aria-pressed="true"]) {
  color: var(--ink);
  border-color: rgba(157,120,255,.62);
  background:
    radial-gradient(circle at 90% 5%, rgba(123,108,255,.18), transparent 12rem),
    linear-gradient(145deg, rgba(27,34,48,.98), rgba(18,24,34,.96));
  box-shadow: 0 0 0 2px rgba(123,108,255,.12), var(--shadow-sm);
}
html[data-theme="dark"] .concept-choice[data-concept="tool"] { opacity: 1; }
html[data-theme="dark"] :is(.concept-choice span:last-child, .package-choice span, .option-card span, .counter-card p, .detail-card li, .summary-line, .summary-note) {
  color: var(--muted);
}
html[data-theme="dark"] .counter-controls button {
  color: var(--ink);
  background: var(--surface-strong);
  border-color: var(--line-strong);
}