@font-face {
  /* ISO 3098 technical lettering (osifont, LGPL with font exception) */
  font-family: 'osifont';
  src: url('https://cdn.jsdelivr.net/gh/hikikomori82/osifont@master/osifont-lgpl3fe.ttf') format('truetype');
  font-display: swap;
}
:root {
  --iso: 'osifont', 'IBM Plex Mono', monospace;
  --ink-solid: #151515;
  --grid-1: rgba(21, 21, 21, 0.05);
  --grid-2: rgba(21, 21, 21, 0.13);
  --ok: #1d6b3a;
  --desk: #d6d2c6;
  --paper: #ebe9e2;
  --paper-2: #e3e0d7;
  --ink: #151515;
  --ink-2: rgba(21, 21, 21, 0.62);
  --ink-3: rgba(21, 21, 21, 0.38);
  --rule: rgba(21, 21, 21, 0.85);
  --hair: rgba(21, 21, 21, 0.16);
  --accent: #df4519;
  --serif: 'Instrument Serif', 'Times New Roman', serif;
  --mono: 'IBM Plex Mono', ui-monospace, Menlo, Consolas, monospace;
  --sans: 'IBM Plex Sans', system-ui, sans-serif;
  color-scheme: light;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  background: var(--desk);
  color: var(--ink);
  font: 12px/1.45 var(--sans);
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 2px; }
.ok { color: var(--ok); font-style: normal; }
.bad { color: var(--accent); font-style: normal; }

/* ---------- frame & sheet ---------- */
.frame { position: fixed; inset: 0; padding: 20px 18px 16px 26px; }
.zones { position: absolute; display: flex; font: 500 9px var(--mono); color: var(--ink-3); pointer-events: none; }
.zones-top { left: 26px; right: 18px; top: 4px; }
.zones-top span { flex: 1; text-align: center; border-left: 1px solid var(--hair); line-height: 12px; }
.zones-top span:first-child { border-left: 0; }
.zones-left { top: 20px; bottom: 16px; left: 8px; flex-direction: column; }
.zones-left span { flex: 1; display: flex; align-items: center; border-top: 1px solid var(--hair); }
.zones-left span:first-child { border-top: 0; }

.sheet {
  height: 100%;
  border: 1.5px solid var(--rule);
  outline: 1px solid var(--rule); outline-offset: 3px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 380px;
  grid-template-rows: auto minmax(0, 1fr) 40px 184px auto;
  grid-template-areas: 'head head' 'draw spec' 'scrub spec' 'rec spec' 'tb tb';
  background: var(--paper);
}

/* ---------- head ---------- */
.head {
  grid-area: head;
  display: grid; grid-template-columns: auto auto minmax(0, 1fr) auto; gap: 30px; align-items: end;
  padding: 16px 20px 14px; border-bottom: 1px solid var(--rule);
}
.title h1 { margin: 0; font: 400 64px/0.9 var(--serif); letter-spacing: -0.02em; }
.title .sub { margin: 6px 0 0; font: italic 400 17px/1.2 var(--serif); color: var(--ink-2); }
.lede { margin: 0; max-width: 62ch; color: var(--ink-2); font-size: 12.5px; line-height: 1.55; }
.kpis { display: flex; margin: 0; border-left: 1px solid var(--hair); }
.kpis div { padding: 0 18px; border-right: 1px solid var(--hair); }
.kpis dt { font: 500 9px var(--mono); text-transform: uppercase; letter-spacing: 0.14em; color: var(--ink-3); }
.kpis dd { margin: 4px 0 0; font: 400 30px/1 var(--serif); font-variant-numeric: tabular-nums; }

.cell-label {
  position: absolute; left: 12px; top: 8px; z-index: 2;
  font: italic 400 13px var(--serif); color: var(--ink-2);
}

/* ---------- drawing ---------- */
.drawing {
  grid-area: draw; position: relative; min-height: 0; min-width: 0; overflow: hidden;
  border-right: 1px solid var(--rule);
  background-image:
    linear-gradient(var(--hair) 1px, transparent 1px),
    linear-gradient(90deg, var(--hair) 1px, transparent 1px);
  background-size: 100% 40px, 40px 100%;
  background-position: -1px -1px;
  background-color: var(--paper);
}
.drawing::before {
  /* fade the grid so the linework dominates */
  content: ''; position: absolute; inset: 0; background: color-mix(in srgb, var(--paper) 72%, transparent); pointer-events: none;
}
.pid { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
@keyframes plot { from { stroke-dashoffset: 1; } to { stroke-dashoffset: 0; } }
.sight { position: absolute; border-radius: 50%; display: none; pointer-events: none; }

.notes {
  position: absolute; right: 14px; bottom: 10px; margin: 0; padding: 8px 10px 8px 26px; max-width: 290px;
  font: 400 9.5px/1.45 var(--mono); color: var(--ink-2); background: var(--paper);
  border: 1px solid var(--hair);
}
.notes::before { content: 'NOTES'; display: block; margin-left: -16px; font-weight: 600; color: var(--ink); letter-spacing: 0.1em; }

/* SVG linework */
.pid text { font-family: var(--mono); fill: var(--ink); }
.pipe { fill: none; stroke: var(--ink); stroke-width: 1.4; }
.pipe.inlet { stroke-width: 2; }
.flow { fill: none; stroke: var(--accent); stroke-width: 2.2; stroke-dasharray: 2 8; opacity: 0; transition: opacity 0.4s; }
.arrowhead { fill: var(--ink); }
.shell-bg { fill: var(--paper); }
.shell { fill: none; stroke: var(--ink); stroke-width: 1.6; }
.vessel { cursor: pointer; }
.vessel.over .shell { stroke: var(--accent); stroke-width: 2.4; }
.liquid { fill: url(#hatch); }
.liquid.hot { fill: url(#hatch-hot); }
.hatch-line { stroke: var(--ink-2); stroke-width: 1; }
.hatch-hot { stroke: var(--accent); stroke-width: 1.2; }
.level { stroke: var(--ink); stroke-width: 1.2; }
.level-tri { fill: none; stroke: var(--ink); stroke-width: 1; }
.mark { stroke: var(--accent); stroke-width: 1.2; }
.vent { fill: none; stroke: var(--ink); stroke-width: 1.2; }
.sight-ring { fill: none; stroke: var(--ink); stroke-width: 2.4; }
.bolt { fill: var(--ink); }
.bubble { fill: var(--paper); stroke: var(--ink); stroke-width: 1.1; }
.bubble-l { stroke: var(--ink); stroke-width: 0.8; }
.bubble-t { font-size: 7.5px; font-weight: 600; text-anchor: middle; }
.reading { font-size: 10px; font-weight: 600; font-variant-numeric: tabular-nums; }
.vid { font-family: var(--serif) !important; font-size: 17px; text-anchor: middle; }
.leader { stroke: var(--ink); stroke-width: 0.7; }
.lbl { font-size: 9px; letter-spacing: 0.08em; }
.lbl.dim { fill: var(--ink-3) !important; }
.lbl.mid, .vname { text-anchor: middle; }
.vname { font-size: 9.5px; font-weight: 600; letter-spacing: 0.08em; }

.valve { cursor: pointer; }
.valve .hit { fill: transparent; }
.bowtie { fill: var(--ink); stroke: var(--ink); stroke-width: 1.1; stroke-linejoin: round; }
.stem { stroke: var(--ink); stroke-width: 1.1; }
.disc { fill: none; stroke: var(--ink); stroke-width: 1.8; }
.tag { fill: var(--paper); stroke: var(--ink); stroke-width: 1; }
.tag-t { font-size: 8.5px; font-weight: 600; text-anchor: middle; letter-spacing: 0.04em; }
.cloud { fill: none; stroke: var(--accent); stroke-width: 1.1; opacity: 0; }
.delta { opacity: 0; }
.delta-tri { fill: var(--paper); stroke: var(--accent); stroke-width: 1.1; }
.delta-t { font-size: 7px; font-weight: 600; text-anchor: middle; fill: var(--accent) !important; }
.valve.open .bowtie { fill: var(--paper); stroke: var(--accent); stroke-width: 1.5; }
.valve.open .stem, .valve.open .disc { stroke: var(--accent); }
.valve.open .cloud, .valve.open .delta { opacity: 1; }
.valve.open .tag-t { fill: var(--accent); }
.valve.revealed .bowtie { fill: var(--paper); }
.valve.sel .tag { stroke-width: 2; }
.valve:hover .tag { fill: var(--paper-2); }
.pulse.buy { fill: var(--ink); }
.pulse.sell { fill: var(--paper); stroke: var(--ink); stroke-width: 1.2; }

/* inspection stamp */
.stamp {
  position: absolute; left: 50%; top: 42%; z-index: 3; pointer-events: none;
  width: 300px; padding: 12px 16px 14px; text-align: center;
  color: var(--accent); border: 3px double var(--accent); border-radius: 4px;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  transform: translate(-50%, -50%) rotate(-7deg) scale(1.5); opacity: 0;
  -webkit-mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -2.2 1.9'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -2.2 1.9'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
.stamp.on { animation: stamp 6.5s cubic-bezier(0.2, 0.9, 0.3, 1) both; }
@keyframes stamp {
  0% { opacity: 0; transform: translate(-50%, -50%) rotate(-7deg) scale(1.5); }
  6% { opacity: 1; transform: translate(-50%, -50%) rotate(-7deg) scale(0.97); }
  9% { transform: translate(-50%, -50%) rotate(-7deg) scale(1); }
  85% { opacity: 1; }
  100% { opacity: 0; transform: translate(-50%, -50%) rotate(-7deg) scale(1); }
}
.s-top { font: 600 11px var(--mono); letter-spacing: 0.4em; text-transform: uppercase; }
.s-tag { font: 400 46px/1 var(--serif); margin: 4px 0 2px; }
.s-line { font: 500 10px var(--mono); letter-spacing: 0.12em; text-transform: uppercase; }
.s-say { margin-top: 8px; padding-top: 8px; border-top: 1px solid var(--accent); font: italic 400 16px/1.25 var(--serif); color: var(--ink); }

/* ---------- spec column ---------- */
.spec { grid-area: spec; display: flex; flex-direction: column; min-height: 0; overflow: hidden; }
.tabs { display: flex; border-bottom: 1px solid var(--rule); flex: none; }
.tabs button {
  flex: 1; background: none; border: 0; border-left: 1px solid var(--hair); padding: 9px 0 8px; cursor: pointer;
  font: 500 10px var(--mono); letter-spacing: 0.14em; text-transform: uppercase; color: var(--ink-3);
}
.tabs button:first-child { border-left: 0; }
.tabs button:hover { color: var(--ink); background: var(--paper-2); }
.tabs button.on { color: var(--ink); background: var(--paper); box-shadow: inset 0 -2px 0 var(--ink); }
.pane { display: none; flex: 1; min-height: 0; overflow-y: auto; }
.pane.on { display: block; }
.pane .block:last-child { border-bottom: 0; }
.block { padding: 12px 16px 14px; border-bottom: 1px solid var(--rule); }
.block.grow { flex: 1; min-height: 0; display: flex; flex-direction: column; border-bottom: 0; }
.spec h2 {
  margin: 0 0 8px; font: 400 19px/1.1 var(--serif);
  display: flex; align-items: baseline; gap: 10px;
}
.spec h2 span { font: 500 9px var(--mono); text-transform: uppercase; letter-spacing: 0.14em; color: var(--ink-3); }
.tbl { width: 100%; border-collapse: collapse; font: 400 11px/1.35 var(--mono); }
.tbl th { text-align: left; font-weight: 500; font-size: 9px; text-transform: uppercase; letter-spacing: 0.12em; color: var(--ink-3); border-bottom: 1px solid var(--ink); padding: 0 6px 4px 0; }
.tbl td { padding: 4px 6px 4px 0; border-bottom: 1px solid var(--hair); vertical-align: top; }
.tbl tbody tr { cursor: pointer; }
.tbl tbody tr:hover { background: var(--paper-2); }
.tbl tr.sel td { background: rgba(21, 21, 21, 0.06); }
.tbl .tagc { font-weight: 600; white-space: nowrap; }
.tbl sup { color: var(--accent); font-size: 8px; margin-left: 2px; }
.tbl .hash { color: var(--ink-3); }
.tbl .state { text-transform: uppercase; font-size: 9.5px; letter-spacing: 0.08em; }
.tbl tr.open .state, .tbl tr.open .tagc { color: var(--accent); }
.tbl tr.revealed .state { color: var(--ink-3); }
.tbl .num { text-align: right; font-variant-numeric: tabular-nums; }
.tbl .bar { display: block; height: 2px; margin-top: 3px; background: var(--hair); }
.tbl .bar i { display: block; height: 100%; width: 0; background: var(--ink); transition: width 0.25s linear; }
.tbl tr.over .bar i { background: var(--accent); }
.tbl tr.over .num { color: var(--accent); }
.spec-c { font-family: var(--sans); font-size: 11px; }

.detail h2 { margin-bottom: 6px; }
.kv { display: grid; grid-template-columns: 82px minmax(0, 1fr); gap: 4px 10px; margin: 0; font-size: 11.5px; }
.kv dt { font: 500 9px/1.9 var(--mono); text-transform: uppercase; letter-spacing: 0.12em; color: var(--ink-3); }
.kv dd { margin: 0; overflow-wrap: anywhere; }
.kv .mono { font-family: var(--mono); }
.kv .small { font-size: 10px; color: var(--ink-2); }
.kv .say { font: italic 400 15px/1.3 var(--serif); }
.kv .muted { color: var(--ink-2); }
.kv .st-open { color: var(--accent); text-transform: uppercase; font: 600 10px/1.9 var(--mono); letter-spacing: 0.1em; }
.kv .st-sealed, .kv .st-revealed { text-transform: uppercase; font: 600 10px/1.9 var(--mono); letter-spacing: 0.1em; }
.audit { display: inline-block; margin-top: 10px; font: 500 10px var(--mono); text-transform: uppercase; letter-spacing: 0.12em; }

.revs { list-style: none; margin: 0; padding: 0; overflow: auto; flex: 1; min-height: 0; font: 400 10.5px/1.4 var(--mono); }
.revs li { display: grid; grid-template-columns: 34px 58px minmax(0, 1fr); gap: 6px; padding: 4px 0; border-bottom: 1px solid var(--hair); animation: rev 0.6s ease-out; }
.revs .rn { color: var(--accent); font-weight: 600; }
.revs .rt { color: var(--ink-3); }
.revs i { color: var(--ink-3); font-style: normal; }
.revs:empty::before { content: 'No revisions. Every valve is as sealed.'; color: var(--ink-3); font-family: var(--serif); font-style: italic; font-size: 14px; }
@keyframes rev { from { background: rgba(223, 69, 25, 0.14); } }

/* ---------- recorder ---------- */
.recorder { grid-area: rec; position: relative; border-top: 1px solid var(--rule); border-right: 1px solid var(--rule); min-width: 0; }
.recorder canvas { position: absolute; left: 0; right: 0; bottom: 0; top: 26px; width: 100%; height: calc(100% - 26px); display: block; }

/* ---------- title block ---------- */
.tb { grid-area: tb; display: grid; grid-template-columns: 1.3fr 0.9fr 0.4fr 1.8fr 1fr 1.1fr 0.9fr 0.9fr 0.8fr 1fr 0.7fr 0.6fr 0.6fr; border-top: 1.5px solid var(--rule); }
.tb-cell { padding: 6px 10px 7px; border-left: 1px solid var(--hair); min-width: 0; display: flex; flex-direction: column; justify-content: center; }
.tb-cell:first-child { border-left: 0; }
.tb-cell span { font: 500 8.5px var(--mono); text-transform: uppercase; letter-spacing: 0.12em; color: var(--ink-3); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.tb-cell b { font: 500 11.5px/1.3 var(--mono); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; font-variant-numeric: tabular-nums; }
.tb-cell b i { font-style: normal; }
.tb-cell:first-child b { font: 400 20px/1 var(--serif); letter-spacing: 0.04em; }
.tb-link { font: 600 11px var(--mono); text-transform: uppercase; letter-spacing: 0.1em; }

/* ---------- responsive ---------- */
@media (max-width: 1280px) {
  .sheet { grid-template-columns: minmax(0, 1fr) 330px; }
  .lede { display: none; }
  .head { grid-template-columns: auto minmax(0, 1fr); }
  .kpis { justify-self: end; }
  .tb { grid-template-columns: repeat(7, minmax(0, 1fr)); }
  .tb-cell { border-top: 1px solid var(--hair); }
}
@media (max-width: 900px) {
  body { overflow: auto; }
  .frame { position: static; padding: 10px; }
  .zones { display: none; }
  .sheet {
    height: auto; outline: 0;
    grid-template-columns: minmax(0, 1fr);
    grid-template-rows: auto auto auto auto auto auto;
    grid-template-areas: 'head' 'draw' 'scrub' 'rec' 'spec' 'tb';
  }
  .head { grid-template-columns: 1fr; gap: 14px; padding: 14px; }
  .title h1 { font-size: 48px; }
  .lede { display: block; }
  .kpis { justify-self: stretch; border-left: 0; }
  .kpis div { flex: 1; padding: 0 10px 0 0; border-right: 0; }
  .kpis dd { font-size: 24px; }
  .drawing { height: 150vw; max-height: 860px; border-right: 0; }
  .notes { display: none; }
  .recorder { height: 214px; border-right: 0; }
  .block.grow { min-height: 260px; }
  .tb { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stamp { width: 250px; }
  .s-tag { font-size: 36px; }
}
@media (prefers-reduced-motion: reduce) {
  .pid, .stamp.on { animation: none; }
}

/* ---------- audit page ---------- */
body.doc-page { overflow: auto; height: auto; font-size: 13px; }
@media (max-height: 760px) { .notes { display: none; } }

/* projection, trace share, own trades */
.ghost { stroke: var(--accent); stroke-width: 1.2; stroke-dasharray: 3 2; opacity: 0; transition: opacity 0.2s; }
.share { font-family: var(--mono); font-size: 9.5px; font-weight: 600; fill: var(--accent) !important; }
.pulse.mine { fill: var(--accent); }
.pulse.sell.mine { fill: var(--paper); stroke: var(--accent); }
.drawing .notes { display: none; }

/* ---------- history scrubber ---------- */
.scrub {
  grid-area: scrub; display: flex; align-items: center; gap: 10px; padding: 0 12px;
  border-top: 1px solid var(--rule); border-right: 1px solid var(--rule); min-width: 0;
}
.sbtn {
  flex: none; height: 24px; padding: 0 10px; border: 1px solid var(--ink); background: var(--paper); color: var(--ink);
  font: 500 9.5px var(--mono); letter-spacing: 0.12em; text-transform: uppercase; cursor: pointer;
}
.sbtn:hover { background: var(--paper-2); }
.sbtn-hi { background: var(--ink); color: var(--paper); }
.sbtn-hi:hover { background: #333; }
.ruler { position: relative; flex: 1; min-width: 80px; height: 24px; }
.ruler input[type=range] {
  -webkit-appearance: none; appearance: none; width: 100%; height: 24px; margin: 0; background: transparent; cursor: ew-resize;
  background-image:
    linear-gradient(var(--ink), var(--ink)),
    repeating-linear-gradient(90deg, var(--ink-3) 0 1px, transparent 1px 10%),
    repeating-linear-gradient(90deg, var(--hair) 0 1px, transparent 1px 2%);
  background-size: 100% 1px, 100% 9px, 100% 5px;
  background-position: 0 12px, 0 13px, 0 13px;
  background-repeat: no-repeat;
}
.ruler input[type=range]::-webkit-slider-thumb { -webkit-appearance: none; width: 2px; height: 22px; background: var(--accent); border: 0; box-shadow: 0 0 0 3px rgba(223, 69, 25, 0.15); }
.ruler input[type=range]::-moz-range-thumb { width: 2px; height: 22px; background: var(--accent); border: 0; border-radius: 0; }
.marks { position: absolute; inset: 0; pointer-events: none; }
.marks i {
  position: absolute; top: -1px; transform: translateX(-50%); font: 600 7.5px var(--mono); font-style: normal;
  color: var(--accent); background: var(--paper); padding: 0 1px; line-height: 9px;
}
.marks i::after { content: ''; position: absolute; left: 50%; top: 9px; width: 1px; height: 6px; background: var(--accent); }
.scrub-label { flex: none; min-width: 150px; font: 500 10px var(--mono); color: var(--ink-2); font-variant-numeric: tabular-nums; }
body.scrubbing .scrub-label { color: var(--accent); }
body.scrubbing .drawing { box-shadow: inset 0 0 0 2px var(--accent); }
body.scrubbing .cell-label #figMode { color: var(--accent); }

/* ---------- forms, lists ---------- */
.hint { margin: 0 0 10px; color: var(--ink-2); font-size: 11.5px; line-height: 1.45; }
.hint.bad, .bad.hint { color: var(--accent); }
.acc { color: var(--accent); }
.spec h3 { margin: 14px 0 6px; font: 500 9px var(--mono); text-transform: uppercase; letter-spacing: 0.14em; color: var(--ink-3); }
.form-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; margin-bottom: 10px; }
.form-grid label { display: flex; flex-direction: column; gap: 3px; font: 500 9px var(--mono); text-transform: uppercase; letter-spacing: 0.12em; color: var(--ink-3); position: relative; }
.form-grid label span { position: absolute; right: 6px; bottom: 6px; text-transform: none; letter-spacing: 0; }
.form-actions { grid-column: 1 / -1; display: flex; gap: 6px; }
input[type=number], .guess-form input, .watch-form input {
  width: 100%; min-width: 0; height: 28px; padding: 0 8px; border: 1px solid var(--ink); background: var(--paper);
  font: 400 12px var(--mono); color: var(--ink); border-radius: 0;
}
input:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
.guess-form { display: grid; grid-template-columns: 100px minmax(0, 1fr) auto; gap: 6px; margin-bottom: 6px; }
.guess-form .sbtn, .watch-form .sbtn { height: 28px; }
.watch-form { display: flex; gap: 6px; margin-bottom: 12px; }
.guesses, .toplist, .audit-list, .notes-list { list-style: none; margin: 0; padding: 0; font: 400 11px/1.45 var(--mono); }
.guesses li { padding: 4px 0; border-bottom: 1px solid var(--hair); overflow-wrap: anywhere; }
.guesses li span { color: var(--ink-3); margin-right: 6px; }
.guesses li.credited { background: rgba(223, 69, 25, 0.07); }
.guesses em { font-style: normal; color: var(--accent); font-weight: 600; }
.guesses .empty { color: var(--ink-3); font-family: var(--serif); font-style: italic; font-size: 14px; }
.toplist li { display: flex; justify-content: space-between; padding: 3px 0; border-bottom: 1px solid var(--hair); }
.toplist button { background: none; border: 0; padding: 0; font: inherit; color: var(--ink); text-decoration: underline; text-underline-offset: 2px; cursor: pointer; }
.trace-tbl { margin-top: 10px; }
.audit-sum { margin: 0 0 8px; font: 600 11px var(--mono); }
.audit-sum.ok { color: var(--ok); }
.audit-sum.bad { color: var(--accent); }
.audit-list li { padding: 3px 0; border-bottom: 1px solid var(--hair); }
.audit-list li.ok b { color: var(--ok); }
.audit-list li.bad { color: var(--accent); }
.audit-list li.skip { color: var(--ink-3); }
.notes-list { counter-reset: n; color: var(--ink-2); }
.notes-list li { counter-increment: n; padding: 3px 0 3px 20px; position: relative; }
.notes-list li::before { content: counter(n) '.'; position: absolute; left: 0; color: var(--ink); }
.next-name { margin: 0; font: 400 30px/1 var(--serif); }
.revs { max-height: none; }
@media (max-width: 900px) {
  .scrub { border-right: 0; height: auto; padding: 8px 10px; flex-wrap: wrap; }
  .ruler { order: -1; flex-basis: 100%; }
  .scrub-label { min-width: 0; flex: 1; }
  .pane { overflow: visible; }
  .spec { overflow: visible; }
}

/* ---------- drafting lettering ---------- */
.pid text { font-family: var(--iso); }
.pid .reading, .pid .share { font-family: var(--mono); }
.tag-t { font-size: 10px; font-weight: 400; letter-spacing: 0.06em; }
.lbl { font-size: 10px; letter-spacing: 0.1em; }
.bubble-t { font-size: 8.5px; font-weight: 400; }
.vid { font-family: var(--serif) !important; }
.cell-label, .spec h2 span, .tabs button, .tb-cell span, .kpis dt { font-family: var(--iso); letter-spacing: 0.12em; }
.tb-cell span { font-size: 10px; }

/* ---------- fig. 0 ---------- */
.fig0 { margin: 0; display: flex; flex-direction: column; align-items: center; gap: 2px; }
.fig0 svg { width: 58px; height: 74px; }
.fig0 .f0 { fill: none; stroke: var(--ink); stroke-width: 1.1; stroke-linejoin: round; }
.fig0 .f0.thin { stroke-width: 0.6; }
.fig0 .f0.fill { fill: url(#fig0hatch); fill: var(--ink-3); stroke: none; opacity: 0.55; }
.fig0 figcaption { font: italic 400 10.5px var(--serif); color: var(--ink-2); white-space: nowrap; }

/* ---------- view switch ---------- */
.viewsw { position: absolute; right: 12px; top: 8px; z-index: 2; display: flex; border: 1px solid var(--ink); background: var(--paper); }
.viewsw button { border: 0; background: none; padding: 4px 10px; font: 400 10.5px var(--iso); letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-3); cursor: pointer; }
.viewsw button + button { border-left: 1px solid var(--ink); }
.viewsw button.on { background: var(--ink); color: var(--paper); }
.pid[hidden] { display: none; }

/* ---------- pen-drawn revisions ---------- */
.cloud { stroke-dasharray: 1; stroke-dashoffset: 1; }
.valve.open .cloud { animation: pen 1.6s cubic-bezier(0.5, 0, 0.3, 1) forwards; }
.valve.open .delta { animation: fadein 0.5s 1.2s both; }
@keyframes pen { to { stroke-dashoffset: 0; } }
@keyframes fadein { from { opacity: 0; } to { opacity: 1; } }

/* ---------- isometric ---------- */
.iso .g-min { stroke: var(--grid-1); stroke-width: 1; }
.iso .g-maj { stroke: var(--grid-2); stroke-width: 1; }
.iso .axis { stroke: var(--ink-2); stroke-width: 1; }
.iso .pipe-halo { fill: none; stroke: var(--paper); stroke-width: 7; stroke-linecap: butt; }
.iso .pipe { stroke-width: 1.6; stroke-linejoin: round; }
.iso .support { stroke: var(--ink-3); stroke-width: 0.8; stroke-dasharray: 2 2; }
.iso .shade { stroke: var(--ink-3); stroke-width: 0.6; }
.iso .shell.top { fill: var(--paper); }
.iso .surface { fill: color-mix(in srgb, var(--paper) 70%, transparent); stroke: var(--ink); stroke-width: 1; }
.iso .ghost { fill: none; }
.iso .wheel { fill: none; }

/* ---------- detail A ---------- */
.detail-bg { fill: var(--paper); }
.detail-border { fill: none; stroke: var(--ink); stroke-width: 1.4; }
.detail-border.thin { stroke-width: 0.6; }
.detail-leader { stroke-dasharray: 5 3; }
.detail-ring { fill: none; stroke: var(--ink); stroke-width: 0.9; }
.detail-letter, .detail-title { font-size: 11px; letter-spacing: 0.08em; }
.d-line { fill: none; stroke: var(--ink); stroke-width: 1.2; }
.d-line.thick { stroke-width: 2.4; }
.d-cut { fill: url(#hatch); stroke: var(--ink); stroke-width: 1.2; }
.d-gate { fill: var(--ink); }
.d-wheel { fill: none; stroke: var(--ink); stroke-width: 1.6; }
.d-spoke { stroke: var(--ink); stroke-width: 1; }
.d-wire { fill: none; stroke: var(--accent); stroke-width: 1; }
.d-lead { fill: var(--accent); }
.d-seal, .d-cutwire { transition: opacity 0.6s; }
.detail-a.open .d-gate { fill: var(--accent); }

/* ---------- title block controls ---------- */
.tb-btn { align-self: flex-start; background: none; border: 0; border-bottom: 1px solid var(--ink); padding: 0; font: 500 11.5px var(--mono); color: var(--ink); cursor: pointer; }
.detail-actions { display: flex; align-items: center; gap: 12px; margin-top: 10px; }
.detail-actions .audit { margin-top: 0; }

/* ---------- paper ---------- */
.sheet {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='f'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.012 0.9' numOctaves='3' seed='4'/%3E%3CfeColorMatrix values='0 0 0 0 0.3 0 0 0 0 0.28 0 0 0 0 0.24 0 0 0 0.05 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23f)'/%3E%3C/svg%3E");
}

/* ---------- blueprint ---------- */
body.blueprint {
  --desk: #0b2347;
  --paper: #143a6e;
  --paper-2: #1a4580;
  --ink: #eaf2ff;
  --ink-solid: #eaf2ff;
  --ink-2: rgba(234, 242, 255, 0.72);
  --ink-3: rgba(234, 242, 255, 0.48);
  --rule: rgba(234, 242, 255, 0.85);
  --hair: rgba(234, 242, 255, 0.16);
  --grid-1: rgba(234, 242, 255, 0.07);
  --grid-2: rgba(234, 242, 255, 0.17);
  --accent: #ffcf4a;
  --ok: #9ff0b8;
  color-scheme: dark;
}
body.blueprint .sbtn-hi { background: var(--ink); color: var(--paper); }
body.blueprint .sbtn-hi:hover { background: #ffffff; }

/* ---------- print: one A3 sheet ---------- */
@media print {
  @page { size: A3 landscape; margin: 8mm; }
  body { overflow: visible; background: #fff; }
  .frame { position: static; padding: 0; }
  .zones, .scrub, .tabs, .viewsw, .stamp, .detail, .tb-btn, #fluid { display: none !important; }
  .sheet { height: 270mm; }
  .pane { display: none !important; }
  .pane[data-pane=valves] { display: block !important; overflow: visible; }
}
@media (max-width: 1280px) { .fig0 { display: none; } }

/* ---------- the sheet on the desk ---------- */
.sheet {
  position: relative;
  background-color: var(--paper);
  box-shadow: 0 1px 1px rgba(0, 0, 0, 0.08), 0 10px 34px -8px rgba(0, 0, 0, 0.28);
}
/* creases left by the A1 fold: a soft valley and a lit ridge on each fold line */
.sheet::after {
  content: ''; position: absolute; inset: 0; pointer-events: none; z-index: 6;
  background:
    linear-gradient(90deg, transparent calc(50% - 7px), rgba(0, 0, 0, 0.045) calc(50% - 1px), rgba(255, 255, 255, 0.35) calc(50% + 1px), transparent calc(50% + 7px)),
    linear-gradient(180deg, transparent calc(50% - 7px), rgba(0, 0, 0, 0.04) calc(50% - 1px), rgba(255, 255, 255, 0.3) calc(50% + 1px), transparent calc(50% + 7px));
  mix-blend-mode: multiply;
}
body.blueprint .sheet::after { mix-blend-mode: screen; opacity: 0.35; }

/* ---------- unfold on arrival ---------- */
.unfold { position: fixed; z-index: 70; perspective: 2600px; cursor: pointer; }
.uf-desk { position: absolute; background: var(--desk); }
.uf-desk-r { left: 50%; top: 0; width: 50%; height: 50%; animation: ufhide 0s 1.3s forwards; }
.uf-desk-b { left: 0; top: 50%; width: 100%; height: 50%; animation: ufhide 0s 2.1s forwards; }
.uf-tl, .uf-face {
  background-color: var(--paper-2);
  background-image:
    linear-gradient(var(--grid-1) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-1) 1px, transparent 1px);
  background-size: 40px 40px;
}
.uf-tl { position: absolute; left: 0; top: 0; width: 50%; height: 50%; box-shadow: 0 14px 40px -10px rgba(0, 0, 0, 0.45); animation: ufhide 0s 1.3s forwards; }
.uf-flap { position: absolute; transform-style: preserve-3d; }
.uf-face { position: absolute; inset: 0; backface-visibility: hidden; -webkit-backface-visibility: hidden; }
.uf-right { left: 50%; top: 0; width: 50%; height: 50%; z-index: 3; transform-origin: left center; transform: rotateY(-180deg);
  animation: ufRight 0.8s cubic-bezier(0.6, 0.05, 0.3, 1) 0.5s forwards, ufhide 0s 1.3s forwards; }
.uf-right .uf-front { background-image: linear-gradient(90deg, rgba(0, 0, 0, 0.12), transparent 18%), linear-gradient(var(--grid-1) 1px, transparent 1px), linear-gradient(90deg, var(--grid-1) 1px, transparent 1px); background-size: auto, 40px 40px, 40px 40px; }
.uf-right .uf-back { transform: rotateY(180deg); }
.uf-bottom { left: 0; top: 50%; width: 100%; height: 50%; z-index: 4; opacity: 0; transform-origin: top center; transform: rotateX(180deg);
  animation: ufshow 0s 1.3s forwards, ufBottom 0.8s cubic-bezier(0.6, 0.05, 0.3, 1) 1.3s forwards, ufhide 0.5s 2.15s forwards; }
.uf-bottom .uf-front { background-color: var(--paper); background-image: linear-gradient(180deg, rgba(0, 0, 0, 0.1), transparent 14%), linear-gradient(var(--grid-1) 1px, transparent 1px), linear-gradient(90deg, var(--grid-1) 1px, transparent 1px); background-size: auto, 40px 40px, 40px 40px; }
.uf-bottom .uf-back { transform: rotateX(180deg); }
.uf-cover { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 6px; color: var(--ink); border: 1.5px solid var(--ink); outline: 1px solid var(--ink); outline-offset: -8px; }
.uf-cover b { font: 400 clamp(28px, 4vw, 54px) / 1 var(--serif); }
.uf-cover span { font: 400 11px var(--iso); letter-spacing: 0.16em; color: var(--ink-2); }
@keyframes ufRight { to { transform: rotateY(0deg); } }
@keyframes ufBottom { to { transform: rotateX(0deg); } }
@keyframes ufshow { to { opacity: 1; } }
@keyframes ufhide { to { opacity: 0; visibility: hidden; } }
body.unfolding .zones { opacity: 0; }
.zones { transition: opacity 0.6s; }

/* ---------- ink trace when a valve opens ---------- */
.ink-trace { fill: none; stroke: var(--accent); stroke-width: 3.4; stroke-linecap: round; stroke-dasharray: 1; stroke-dashoffset: 1;
  animation: plot 1.3s cubic-bezier(0.5, 0, 0.3, 1) forwards, fadeout 0.9s 2.1s forwards; }
@keyframes fadeout { to { opacity: 0; } }

/* faces swap exactly when each flap is edge-on (mid-turn); more robust than backface-visibility */
.uf-right .uf-front { opacity: 0; animation: ufshow 0s 0.9s forwards; }
.uf-right .uf-back { animation: ufhide 0s 0.9s forwards; }
.uf-bottom .uf-front { opacity: 0; animation: ufshow 0s 1.7s forwards; }
.uf-bottom .uf-back { animation: ufhide 0s 1.7s forwards; }

/* no backface culling: faces are swapped by time, and the back face is mirrored so it reads correctly while flipped */
.uf-face { backface-visibility: visible; -webkit-backface-visibility: visible; }
.uf-right .uf-back { transform: scaleX(-1); }
.uf-bottom .uf-back { transform: scaleY(-1); }
.uf-right .uf-front, .uf-bottom .uf-front { pointer-events: none; }