.build-page { background: var(--plaster); }
.build-page .nav { position: sticky; top: 0; }

.builder { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(360px, 1fr); min-height: calc(100svh - 70px); }

.stage { position: relative; background: #F1ECE3; min-height: 520px; }
#view { position: absolute; inset: 0; width: 100%; height: 100%; display: block; cursor: grab; touch-action: pan-y; }
#view:active { cursor: grabbing; }
.stage-hint { position: absolute; left: 20px; top: 18px; font-size: 12px; letter-spacing: .12em; text-transform: uppercase; color: rgba(30,28,26,.55); pointer-events: none; }
.walls { position: absolute; left: 20px; bottom: 20px; display: flex; gap: 8px; align-items: center; background: rgba(255,255,255,.75); backdrop-filter: blur(6px); padding: 8px 12px; border-radius: 999px; font-size: 12px; color: var(--ink-2); }
.walls span { margin-right: 4px; }
.walls button { width: 22px; height: 22px; border-radius: 50%; border: 1px solid rgba(0,0,0,.18); cursor: pointer; padding: 0; }
.walls button[aria-checked="true"] { box-shadow: 0 0 0 2px #fff, 0 0 0 3px var(--ink); }

.panel { padding: 40px clamp(20px, 3.5vw, 56px) 40px; border-left: 1px solid var(--rule); display: flex; flex-direction: column; }
.panel h1 { font-family: var(--serif); font-size: clamp(40px, 4vw, 56px); line-height: 1; margin: 8px 0 8px; }

.stepper { list-style: none; display: flex; gap: 6px; padding: 0; margin: 0 0 28px; }
.stepper li { flex: 1; display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--ink-2); padding-top: 10px; border-top: 2px solid var(--rule); transition: border-color .25s, color .25s; }
.stepper li span { width: 20px; height: 20px; border-radius: 50%; border: 1px solid currentColor; display: grid; place-items: center; font-size: 11px; }
.stepper li.active, .stepper li.done { color: var(--ink); border-color: var(--ink); }
.stepper li.done span { background: var(--ink); color: var(--plaster); }

.group-label { font: 500 12px/1 var(--sans); letter-spacing: .12em; text-transform: uppercase; color: var(--ink-2); margin: 28px 0 12px; }
.group-label .muted { text-transform: none; letter-spacing: 0; font-weight: 400; }
.color-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(64px, 1fr)); gap: 10px; }
.chip { display: flex; flex-direction: column; align-items: center; gap: 6px; background: none; border: 0; padding: 4px 0; cursor: pointer; font: 400 12px/1.2 var(--sans); color: var(--ink-2); }
.chip i { width: 44px; height: 44px; border-radius: 50%; border: 1px solid rgba(0,0,0,.14); box-shadow: 0 0 0 3px var(--plaster), 0 0 0 4px transparent; transition: box-shadow .2s, transform .2s; }
.chip:hover i { transform: scale(1.06); }
.chip[aria-checked="true"] { color: var(--ink); font-weight: 500; }
.chip[aria-checked="true"] i { box-shadow: 0 0 0 3px var(--plaster), 0 0 0 5px var(--ink); }
.chip:focus-visible { outline: 2px solid var(--vermilion); outline-offset: 2px; border-radius: 8px; }
.picked { margin-top: 24px; min-height: 3.2em; }

.option-list { display: grid; gap: 12px; margin-top: 24px; }
.option { display: flex; gap: 16px; align-items: center; text-align: left; background: #fff; border: 1px solid var(--rule); border-radius: 10px; padding: 16px; cursor: pointer; font: inherit; color: inherit; transition: border-color .2s, box-shadow .2s; }
.option[aria-checked="true"] { border-color: var(--ink); box-shadow: 0 0 0 1px var(--ink); }
.option .dots { display: flex; gap: 4px; flex-shrink: 0; }
.option .dots i { width: 22px; height: 22px; border-radius: 50%; border: 1px solid rgba(0,0,0,.14); }
.option strong { display: block; font-weight: 600; }
.option small { color: var(--ink-2); font-size: 14px; }

.summary { margin: 24px 0 0; border-top: 1px solid var(--rule); }
.summary div { display: flex; justify-content: space-between; gap: 16px; padding: 12px 0; border-bottom: 1px solid var(--rule); font-size: 15px; }
.summary dt { color: var(--ink-2); }
.summary dd { margin: 0; text-align: right; display: flex; align-items: center; gap: 8px; }
.summary dd i { width: 14px; height: 14px; border-radius: 50%; border: 1px solid rgba(0,0,0,.14); }
.summary .total { font-size: 18px; font-weight: 600; border-bottom: 0; }
.summary .total dt { color: var(--ink); }

.ack { display: flex; gap: 12px; align-items: flex-start; margin-top: 20px; font-size: 14px; color: var(--ink-2); cursor: pointer; }
.ack input { width: 18px; height: 18px; margin-top: 2px; accent-color: var(--ink); flex-shrink: 0; }

.step-nav { display: flex; gap: 12px; margin-top: auto; padding-top: 32px; }
.step-nav .btn { flex: 1; text-align: center; border: 0; cursor: pointer; font-family: var(--sans); }
.step-nav .btn[aria-disabled="true"] { background: #B9B2A8; pointer-events: none; }
.btn-ghost { background: none; border: 1px solid var(--ink); border-radius: 999px; padding: 14px 24px; font: 500 15px var(--sans); color: var(--ink); cursor: pointer; }
.fine-left { font-size: 13px; color: var(--ink-2); margin-top: 16px; }

@media (max-width: 900px) {
  .builder { grid-template-columns: 1fr; }
  .stage { min-height: 0; height: 44svh; position: sticky; top: 62px; z-index: 3; box-shadow: 0 1px 0 var(--rule); }
  .panel { border-left: 0; position: relative; z-index: 1; background: var(--plaster); border-top: 1px solid var(--rule); padding-top: 28px; }
  .step-nav { position: sticky; bottom: 0; background: var(--plaster); padding: 16px 0; margin-top: 24px; }
  .walls { bottom: 10px; left: 10px; padding: 6px 10px; }
  .stage-hint { display: none; }
}