:root {
  --bg: #f4f2ee;
  --surface: #ffffff;
  --surface-2: #ece9e3;
  --border: #d9d4ca;
  --text: #1d1f24;
  --muted: #5e6470;
  --accent: #c76a00;
  --accent-ink: #ffffff;
  --accent-soft: #fbe7cf;
  --ok: #2e7d4f;
  --warn: #a8530a;
  --warn-soft: #fdebd6;
  --fluid: #1f6fb2;
  --radius: 10px;
  --tap: 44px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, monospace;
  color-scheme: light;
}

:root[data-theme="dark"] {
  --bg: #16181d;
  --surface: #1f2228;
  --surface-2: #282c34;
  --border: #363b45;
  --text: #e8e6e1;
  --muted: #9aa0ab;
  --accent: #f39c12;
  --accent-ink: #16181d;
  --accent-soft: #3a2e1a;
  --ok: #5cc98a;
  --warn: #f0a65a;
  --warn-soft: #3b2a19;
  --fluid: #6cb4f0;
  color-scheme: dark;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.45 var(--font);
  padding-bottom: env(safe-area-inset-bottom);
}

h1, h2, h3 { line-height: 1.2; margin: 0 0 .6rem; }
h2 { font-size: 1.1rem; }
h3 { font-size: 1rem; }
p { margin: 0 0 .8rem; }
.hint { color: var(--muted); font-size: .875rem; margin-top: .6rem; }
.num { font-family: var(--mono); font-variant-numeric: tabular-nums; }

/* ---- top bar ---- */
.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; flex-wrap: wrap; gap: .5rem 1rem; align-items: center; justify-content: space-between;
  padding: .6rem 16px; padding-top: max(.6rem, env(safe-area-inset-top));
  background: var(--surface); border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: .5rem; font-size: 1.05rem; margin: 0; }
.logo { width: 22px; height: 22px; border-radius: 6px; background: var(--accent); display: inline-block; }
.topbar-controls { display: flex; gap: .5rem; align-items: center; flex-wrap: wrap; }
.tier-pick { display: flex; align-items: center; gap: .4rem; font-size: .9rem; color: var(--muted); }

/* ---- controls ---- */
button, select, input, textarea { font: inherit; color: inherit; }
.btn, select, input[type="number"], input[type="search"], input[type="text"], textarea {
  min-height: var(--tap);
  border: 1px solid var(--border);
  background: var(--surface-2);
  border-radius: var(--radius);
  padding: 0 .8rem;
}
textarea { width: 100%; padding: .6rem; font-family: var(--mono); font-size: .8rem; }
.btn { cursor: pointer; display: inline-flex; align-items: center; gap: .4rem; white-space: nowrap; }
.btn:hover { border-color: var(--accent); }
.btn.ghost { background: transparent; }
.btn.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); font-weight: 600; }
.icon-btn { width: var(--tap); justify-content: center; padding: 0; }
.pill { background: var(--accent); color: var(--accent-ink); border-radius: 999px; padding: 0 .45rem; font-size: .75rem; font-weight: 700; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---- tabs ---- */
.tabs {
  display: flex; gap: .25rem; overflow-x: auto; scrollbar-width: none;
  padding: .5rem 16px 0; background: var(--surface); border-bottom: 1px solid var(--border);
}
.tabs::-webkit-scrollbar { display: none; }
.tabs button {
  min-height: var(--tap); padding: 0 .9rem; border: 0; background: none; cursor: pointer;
  color: var(--muted); border-bottom: 3px solid transparent; white-space: nowrap; font-weight: 600;
}
.tabs button[aria-selected="true"] { color: var(--text); border-bottom-color: var(--accent); }

main { max-width: 1280px; margin: 0 auto; padding: 16px; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem; }

/* ---- calculator ---- */
.calc-layout { display: grid; gap: 1rem; }
.target-row { display: grid; grid-template-columns: 1fr 6.5rem var(--tap); gap: .5rem; margin-bottom: .5rem; }
.target-row input[type="number"] { width: 100%; text-align: right; }
.target-actions { display: flex; gap: .5rem; flex-wrap: wrap; margin-top: .25rem; }

.item-picker { position: relative; min-width: 0; }
.item-picker input { width: 100%; }
.item-picker ul {
  position: absolute; z-index: 20; left: 0; right: 0; top: calc(100% + 4px);
  max-height: 300px; overflow-y: auto; margin: 0; padding: .25rem; list-style: none;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: 0 8px 24px rgb(0 0 0 / .25);
}
.item-picker li button {
  width: 100%; min-height: var(--tap); text-align: left; border: 0; background: none; border-radius: 6px;
  padding: 0 .6rem; cursor: pointer; display: flex; justify-content: space-between; gap: .5rem;
}
.item-picker li button:hover, .item-picker li button.active { background: var(--accent-soft); }
.item-picker li small { color: var(--muted); }

.summary { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: .6rem; margin-bottom: 1rem; }
.stat { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: .7rem .9rem; }
.stat .label { color: var(--muted); font-size: .8rem; }
.stat .value { font-size: 1.35rem; font-weight: 700; font-family: var(--mono); }
.stat.wide { grid-column: 1 / -1; }
.stat ul { margin: .3rem 0 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: .15rem 1rem; }
.stat li { display: flex; justify-content: space-between; gap: .5rem; font-size: .9rem; }

.notice { border-radius: var(--radius); padding: .7rem .9rem; background: var(--warn-soft); color: var(--warn); margin-bottom: .6rem; font-size: .9rem; }

.view-toggle { display: inline-flex; max-width: 100%; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; margin-bottom: .8rem; }
.view-toggle button { min-height: 40px; padding: 0 .8rem; flex: 1 1 auto; white-space: nowrap; border: 0; background: var(--surface); cursor: pointer; }
.view-toggle button[aria-pressed="true"] { background: var(--accent); color: var(--accent-ink); font-weight: 600; }

.build-list { display: grid; gap: .6rem; }
.step { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: .8rem .9rem; }
.step-head { display: flex; justify-content: space-between; gap: .75rem; align-items: baseline; flex-wrap: wrap; }
.step-head h3 { margin: 0; }
.machines { font-family: var(--mono); font-weight: 700; color: var(--accent); }
.machines small { color: var(--muted); font-weight: 400; }
.step-io { display: grid; grid-template-columns: 1fr 1fr; gap: .3rem 1rem; margin-top: .5rem; font-size: .88rem; }
.step-io h4 { margin: 0; font-size: .72rem; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
.step-io ul { list-style: none; margin: 0; padding: 0; }
.step-io li { display: flex; justify-content: space-between; gap: .5rem; }
.step select { margin-top: .5rem; width: 100%; min-height: 40px; }
.step-meta { color: var(--muted); font-size: .8rem; margin-top: .4rem; }
.fluid { color: var(--fluid); }
.tag { font-size: .7rem; padding: .05rem .4rem; border-radius: 4px; background: var(--accent-soft); color: var(--accent); font-weight: 700; vertical-align: middle; }

.tree, .tree ul { list-style: none; margin: 0; padding-left: 0; }
.tree ul { padding-left: 1.1rem; border-left: 1px dashed var(--border); margin-left: .5rem; }
.tree details > summary { cursor: pointer; min-height: 36px; display: flex; align-items: center; gap: .4rem; flex-wrap: wrap; }
.tree .leaf { min-height: 32px; display: flex; align-items: center; gap: .4rem; padding-left: 1.1rem; }
.tree .rate { font-family: var(--mono); color: var(--muted); }
.tree .mach { font-family: var(--mono); color: var(--accent); font-size: .85rem; }

/* ---- reference ---- */
.ref-grid { display: grid; gap: 1rem; }
.ref-grid > *, .calc-layout > * { min-width: 0; }
.oc-calc select { width: 100%; }
.tier-block h2 { display: flex; align-items: center; gap: .6rem; }
.progress { flex: 1; height: 6px; background: var(--surface-2); border-radius: 3px; overflow: hidden; max-width: 160px; }
.progress span { display: block; height: 100%; background: var(--ok); }
.milestone { border-top: 1px solid var(--border); padding: .6rem 0; }
.milestone:first-of-type { border-top: 0; }
.milestone.done .ms-name { text-decoration: line-through; color: var(--muted); }
.ms-top { display: flex; gap: .6rem; align-items: center; justify-content: space-between; flex-wrap: wrap; }
.check-row { display: flex; align-items: center; gap: .6rem; min-height: var(--tap); cursor: pointer; }
.check-row input { width: 22px; height: 22px; accent-color: var(--accent); flex: none; }
.cost { display: flex; flex-wrap: wrap; gap: .3rem; margin: .3rem 0 0 2rem; padding: 0; list-style: none; }
.cost li { background: var(--surface-2); border-radius: 6px; padding: .15rem .5rem; font-size: .85rem; }
.ms-unlocks { margin: .3rem 0 0 2rem; color: var(--muted); font-size: .8rem; }
.ms-unlocks.why { color: var(--text); font-size: .88rem; }

table { width: 100%; border-collapse: collapse; font-size: .9rem; }
th, td { text-align: left; padding: .45rem .5rem; border-bottom: 1px solid var(--border); }
th { color: var(--muted); font-weight: 600; font-size: .8rem; }
td.num, th.num { text-align: right; }
.table-wrap { overflow-x: auto; }

.oc-calc { display: grid; gap: .6rem; }
.oc-calc label { display: grid; gap: .25rem; font-size: .85rem; color: var(--muted); }
.oc-calc input[type="range"] { width: 100%; accent-color: var(--accent); min-height: var(--tap); }
.oc-out { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: .5rem; }

.alt-pick { border-top: 1px solid var(--border); padding: .7rem 0; }
.alt-pick:first-of-type { border-top: 0; }
.alt-pick .recipe { font-family: var(--mono); font-size: .8rem; color: var(--muted); margin-top: .2rem; }
.alt-pick .owned { color: var(--ok); font-size: .8rem; font-weight: 600; }

.tips { display: grid; gap: .8rem; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }
.tips .card h3 { color: var(--accent); }
.tips .card p { margin: 0; }

/* ---- dialog ---- */
dialog {
  width: min(640px, calc(100vw - 32px)); max-height: calc(100dvh - 32px); padding: 0;
  border: 1px solid var(--border); border-radius: 14px; background: var(--surface); color: var(--text);
}
dialog::backdrop { background: rgb(0 0 0 / .55); }
.dialog-inner { display: flex; flex-direction: column; gap: .6rem; padding: 1rem; max-height: calc(100dvh - 34px); }
.dialog-head { display: flex; justify-content: space-between; align-items: center; gap: .5rem; }
.dialog-head h2 { margin: 0; }
.dialog-inner input[type="search"] { width: 100%; }
.alt-list { overflow-y: auto; flex: 1; min-height: 120px; border: 1px solid var(--border); border-radius: var(--radius); padding: 0 .6rem; }
.alt-list h3 { font-size: .75rem; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); margin: .8rem 0 .2rem; }
.alt-list .check-row small { color: var(--muted); }
.transfer summary { cursor: pointer; min-height: var(--tap); display: flex; align-items: center; color: var(--muted); }

.footer { color: var(--muted); font-size: .8rem; text-align: center; padding: 1rem 16px 2rem; }

/* ---- tablet & up ---- */
@media (min-width: 768px) {
  .calc-layout { grid-template-columns: minmax(300px, 380px) 1fr; align-items: start; }
  .targets-card { position: sticky; top: 76px; }
  .ref-grid.two { grid-template-columns: 1fr 1fr; align-items: start; }
}
@media (min-width: 1100px) {
  .build-list { grid-template-columns: 1fr 1fr; }
}

/* ---- small phones: item name gets its own line ---- */
@media (max-width: 480px) {
  .target-row { grid-template-columns: 1fr var(--tap); }
  .target-row .item-picker { grid-column: 1 / -1; }
}
.ms-top { flex-wrap: nowrap; align-items: flex-start; }
.ms-top > :first-child { flex: 1; min-width: 0; }
.ms-top > .btn { flex: none; }

/* ---- diagrams ---- */
.diagram-wrap { overflow: auto; max-height: 75vh; -webkit-overflow-scrolling: touch; border-radius: 8px; background: var(--bg); }
.diagram-wrap svg { display: block; font-family: var(--font); }
.flow .edge path { fill: none; stroke: var(--muted); stroke-width: 1.6; }
.flow .edge.fluid path { stroke: var(--fluid); }
.flow .edge.loop path { stroke: var(--warn); stroke-dasharray: 5 4; }
.flow .edge rect { fill: var(--surface); stroke: var(--border); }
.flow .edge text { fill: var(--text); font-size: 11px; text-anchor: middle; font-family: var(--mono); }
.flow marker path { fill: var(--muted); }
.flow .box rect { fill: var(--surface-2); stroke: var(--border); stroke-width: 1.5; }
.flow .box.step rect { stroke: var(--accent); }
.flow .box.raw rect { fill: var(--surface); stroke-dasharray: 4 3; }
.flow .box.missing rect, .flow .box.loop rect { fill: var(--warn-soft); stroke: var(--warn); }
.flow .t1 { fill: var(--text); font-size: 13px; font-weight: 700; }
.flow .t2 { fill: var(--accent); font-size: 12px; font-family: var(--mono); }
.flow .box.raw .t2 { fill: var(--muted); }
.flow .t3 { fill: var(--muted); font-size: 11.5px; font-family: var(--mono); }

/* ---- builds ---- */
.build-stage > summary { cursor: pointer; min-height: var(--tap); display: flex; align-items: center; margin-bottom: .6rem; }
.build-grid { display: grid; gap: .8rem; }
.build h3 { display: flex; flex-wrap: wrap; align-items: center; gap: .5rem; }
.kv { margin: .4rem 0; font-size: .88rem; }
.kv th { width: 6.5rem; vertical-align: top; color: var(--muted); font-weight: 600; }
.kv td { overflow-wrap: anywhere; }
.tips-list { margin: .6rem 0 .8rem; padding-left: 1.2rem; font-size: .9rem; }
.tips-list li { margin-bottom: .3rem; }
.planner-form { display: grid; grid-template-columns: 1fr 1fr 7rem; gap: .6rem; margin-bottom: .6rem; }
.planner-form label { display: grid; gap: .25rem; font-size: .85rem; color: var(--muted); min-width: 0; }
.planner-form select, .planner-form input { width: 100%; min-width: 0; }
@media (max-width: 560px) { .planner-form { grid-template-columns: 1fr; } }
@media (min-width: 1100px) { .build-grid { grid-template-columns: 1fr 1fr; } }

/* ---- build plans ---- */
.build-grid > *, .build-stage, .card { min-width: 0; }
.plan-legend { display: flex; flex-wrap: wrap; gap: .3rem .9rem; font-size: .8rem; color: var(--muted); margin: .2rem 0 .6rem; }
.plan-legend span { display: inline-flex; align-items: center; gap: .35rem; }
.lg { display: inline-block; width: 18px; height: 0; border-top: 3px solid var(--muted); }
.lg.pipe { border-top: 3px dashed var(--fluid); }
.lg.lift { border-top: 2px dotted var(--muted); }
.lg.splitter, .lg.merger { width: 11px; height: 11px; border: 0; border-radius: 2px; }
.lg.splitter { background: var(--ok); }
.lg.merger { background: var(--accent); }
.lg.junction { width: 10px; height: 10px; border: 2px solid var(--fluid); border-radius: 50%; }
.lg.hop { width: 18px; height: 9px; border: 0; border-top: 3px solid var(--muted); border-radius: 9px 9px 0 0; }
.build .scale { display: inline-flex; align-items: center; gap: .5rem; font-weight: 600; margin-bottom: .4rem; }
.build .scale input { width: 6rem; }

/* ---- floor plans tab ---- */
.fp-toolbar { display: flex; flex-wrap: wrap; gap: .6rem 1rem; align-items: end; margin-bottom: .6rem; }
.fp-toolbar label { display: grid; gap: .25rem; font-size: .85rem; color: var(--muted); }
.fp-pick { flex: 1 1 240px; min-width: 0; }
.fp-pick select { width: 100%; }
.fp-scale input { width: 6rem; }
.fp-toolbar [hidden] { display: none; }
.fp-zoom { display: flex; gap: .4rem; }
.fp-canvas {
  height: max(380px, calc(100dvh - 240px)); border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--bg); overflow: hidden; touch-action: none; cursor: grab; user-select: none; -webkit-user-select: none;
}
.fp-canvas:active { cursor: grabbing; }
.fp-canvas svg { width: 100%; height: 100%; display: block; }
.fp-info { margin-top: .6rem; }
#fp-notes { margin-top: .6rem; }
svg.fp { font-family: var(--font); }
.fp .fgrid { stroke: var(--border); stroke-width: .6; opacity: .45; fill: none; }
.fp .belt { stroke: var(--muted); stroke-width: 3; fill: none; stroke-linecap: round; }
.fp .pipe { stroke: var(--fluid); stroke-width: 3; fill: none; stroke-dasharray: 7 4; }
.fp .bus { stroke-width: 4; }
.fp .drop { stroke-width: 2; }
.fp .lift { stroke-dasharray: 2 3; }
.fp marker path { fill: var(--muted); }
.fp .fp-splitter { fill: var(--ok); }
.fp .fp-merger { fill: var(--accent); }
.fp .fp-junction { fill: var(--surface); stroke: var(--fluid); stroke-width: 2.5; }
.fp .fp-source rect { fill: var(--surface-2); stroke: var(--border); }
.fp .fp-source text, .fp .fp-store text { fill: var(--text); font-size: 11px; }
.fp .fp-store rect { fill: var(--surface); stroke: var(--ok); }
.fp .fp-store.sink rect { stroke: var(--warn); }
.fp .fp-machine rect { fill: var(--accent-soft); stroke: var(--accent); stroke-width: 1.5; }
.fp .fp-machine.gen rect { fill: var(--surface-2); stroke: var(--ok); }
.fp .fp-machine text { fill: var(--accent); font-size: 11px; font-weight: 700; text-anchor: middle; font-family: var(--mono); pointer-events: none; }
.fp .fp-machine.gen text { fill: var(--ok); font-size: 14px; }
.fp .fp-machine { cursor: pointer; }
.fp .fp-machine:focus rect, .fp .fp-machine:hover rect { stroke-width: 3; }
.fp .fp-title { fill: var(--text); font-size: 14px; font-weight: 700; }
.fp .fp-sub { fill: var(--muted); font-size: 11px; font-family: var(--mono); }
.fp .fp-lane { fill: var(--text); font-size: 10.5px; font-family: var(--mono); paint-order: stroke; stroke: var(--bg); stroke-width: 3px; }
.fp .fp-bus { fill: var(--text); font-size: 11px; font-weight: 600; }