/* bldc-drive: one engineering drawing sheet. Diazo ink on cool paper, one checker's red. */
:root {
  --sc-canvas: #eef0ec;
  --sc-surface: #e3e6e0;
  --sc-ink: #262a6b;
  --sc-ink-soft: #4a4f8a;
  --sc-accent: #262a6b;
  --sc-accent-ink: #eef0ec;
  --sc-font-display: "Barlow Semi Condensed", "Barlow", system-ui, sans-serif;
  --sc-font-text: "Barlow", system-ui, sans-serif;
  --sc-shadow-color: 236 45% 18%;

  --paper: #eef0ec;
  --paper-2: #e3e6e0;
  --ink: #262a6b;
  --ink-2: #4a4f8a;
  --ink-3: #9a9dc6;
  --red: #c42019;
  --gridline: #d5d8de;

  /* lettering heights, ISO 3098 root-2 series */
  --l1: 13px; --l2: 18px; --l3: 25.5px; --l4: 36px; --l5: 51px; --l6: 72px;

  --fr: 22px;                       /* inner frame line inset */
  --bar: 50px;                      /* title strip */
  --gut: clamp(18px, 3.2vw, 52px);  /* gutter inside the frame */
  --pad: calc(var(--fr) + var(--gut));
  --top: calc(var(--fr) + var(--bar));
  --ease: cubic-bezier(0.23, 1, 0.32, 1);
}

body { font-size: var(--l2); line-height: 1.55; letter-spacing: 0; }
::selection { background: var(--ink); color: var(--paper); }
:focus-visible { outline: 2px dashed var(--red); outline-offset: 4px; border-radius: 0; }
sub { font-size: 0.7em; line-height: 0; }
b, strong { font-weight: 600; }
h1, h2, h3 { margin: 0; }
p { margin: 0; }
html { scroll-padding-top: calc(var(--top) + 8px); }

/* ---------------------------------------------------------------- frame -- */
.frame {
  position: fixed; inset: 0; z-index: 70; pointer-events: none;
  border: var(--fr) solid var(--paper);
}
.frame::after { content: ""; position: absolute; inset: 0; border: 2px solid var(--ink); }
.frame::before { content: ""; position: absolute; inset: calc(-1 * var(--fr) + 8px); border: 1px solid var(--ink); }
.zx, .zy { position: absolute; display: grid; font: 500 11px/1 var(--sc-font-display); color: var(--ink-2); }
.zx { left: 0; right: 0; height: calc(var(--fr) - 8px); grid-auto-flow: column; grid-auto-columns: 1fr; }
.zx.t { top: calc(-1 * var(--fr) + 8px); }
.zx.b { bottom: calc(-1 * var(--fr) + 8px); }
.zy { top: 0; bottom: 0; width: calc(var(--fr) - 8px); grid-auto-rows: 1fr; }
.zy.l { left: calc(-1 * var(--fr) + 8px); }
.zy.r { right: calc(-1 * var(--fr) + 8px); }
.zx span, .zy span { display: grid; place-items: center; border-left: 1px solid var(--ink-3); }
.zy span { border-left: 0; border-top: 1px solid var(--ink-3); }
.zx span:first-child { border-left: 0; }
.zy span:first-child { border-top: 0; }

/* ---------------------------------------------------------- title strip -- */
.bar {
  position: fixed; z-index: 60; top: var(--fr); left: var(--fr); right: var(--fr); height: var(--bar);
  display: flex; align-items: center; gap: 22px; padding: 0 8px 0 var(--gut);
  background: var(--paper); border-bottom: 1px solid var(--ink);
  font-family: var(--sc-font-display);
}
.bar-name { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; text-decoration: none; white-space: nowrap; }
.bar-index { display: flex; gap: 4px; margin-left: auto; }
.bar-index a { position: relative; padding: 14px 8px; font: 500 14px/1 var(--sc-font-display); letter-spacing: 0.02em; color: var(--ink-2); text-decoration: none; white-space: nowrap; transition: color 140ms var(--ease); }
.bar-index a::after { content: ""; position: absolute; left: 8px; right: 8px; bottom: 8px; height: 2px; background: var(--ink); transform: scaleX(0); transform-origin: left; transition: transform 200ms var(--ease); }
.bar-index a[aria-current="true"] { color: var(--ink); }
.bar-index a[aria-current="true"]::after { transform: scaleX(1); }
.bar-here { display: none; font: 500 14px var(--sc-font-display); color: var(--ink-2); white-space: nowrap; }
.bar-cta {
  display: inline-flex; align-items: center; height: 36px; padding: 0 16px;
  background: var(--ink); color: var(--paper); text-decoration: none; white-space: nowrap;
  font: 600 15px var(--sc-font-display); letter-spacing: 0.02em;
  transition: background 140ms var(--ease), color 140ms var(--ease);
}
@media (hover: hover) and (pointer: fine) {
  .bar-index a:hover { color: var(--ink); }
  .bar-cta:hover { background: var(--paper); color: var(--ink); box-shadow: inset 0 0 0 2px var(--ink); }
}
.bar-cta:active, .btn:active { transform: translateY(1px); }

/* --------------------------------------------------------------- shared -- */
.wrap { padding-inline: var(--pad); max-width: calc(1440px + 2 * var(--fr)); margin-inline: auto; }
.sc-section { padding-block: clamp(64px, 9vw, 128px); }
.h2 { font: 600 clamp(30px, 3.2vw, var(--l5))/1.04 var(--sc-font-display); letter-spacing: -0.01em; text-wrap: balance; }
.h2.sm { font-size: clamp(26px, 2.4vw, var(--l4)); }
.lede { font-size: clamp(18px, 1.5vw, 21px); line-height: 1.5; max-width: 40em; text-wrap: pretty; }
.lede.strong { font-weight: 600; }
.vlabel {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 4px 16px; margin-top: 10px;
  font: 700 var(--l1)/1.35 var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase;
}
.vlabel span { font: italic 500 15px/1.35 var(--sc-font-display); letter-spacing: 0; text-transform: none; color: var(--ink-2); }
.vlabel span.t { font: inherit; letter-spacing: inherit; text-transform: inherit; color: inherit; }
.tbl { width: 100%; border-collapse: collapse; font-size: 16px; line-height: 1.4; font-variant-numeric: tabular-nums; }
.tbl th, .tbl td { border: 1px solid var(--ink); padding: 7px 12px; text-align: left; vertical-align: top; }
.tbl thead th { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; }
.ref { margin: 0; }
.ref-img { position: relative; overflow: hidden; background: var(--paper-2); aspect-ratio: 16 / 9; }
.ref-img img, .ref-img video { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.ref-img::before, .ref-img::after { content: ""; position: absolute; z-index: 1; width: 22px; height: 22px; border: 2px solid var(--ink); }
.ref-img::before { left: 8px; top: 8px; border-right: 0; border-bottom: 0; }
.ref-img::after { right: 8px; bottom: 8px; border-left: 0; border-top: 0; }
.ref-img.scope { aspect-ratio: 5 / 3; }
.ref-img.scope img, .ref-img.sim img { object-fit: contain; background: #fff; }
.ref-img.sim { aspect-ratio: 1506 / 992; background: #fff; }
.chart { display: block; width: 100%; overflow: visible; }
.chart text { font-family: var(--sc-font-display); fill: var(--ink-2); }

.btn {
  display: inline-flex; align-items: center; gap: 12px; min-height: 52px; padding: 0 24px;
  background: var(--ink); color: var(--paper); border: 2px solid var(--ink); text-decoration: none;
  font: 600 var(--l2) var(--sc-font-display); letter-spacing: 0.03em;
  transition: background 140ms var(--ease), color 140ms var(--ease);
}
.btn svg { width: 22px; height: 10px; }
@media (hover: hover) and (pointer: fine) { .btn:hover { background: var(--paper); color: var(--ink); } }
.lnk { font: 500 var(--l2) var(--sc-font-display); padding: 12px 0; text-decoration-thickness: 1.5px; text-underline-offset: 5px; }

/* ----------------------------------------------------------------- hero -- */
.hero {
  height: 100%; display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: clamp(24px, 4vw, 72px);
  align-items: center; padding: calc(var(--top) + 18px) var(--pad) calc(var(--fr) + 16px);
}
.hero h1 { font: 600 clamp(38px, 4.4vw, 68px)/0.98 var(--sc-font-display); letter-spacing: -0.014em; text-wrap: balance; }
.by { margin-top: 16px; font: 500 var(--l3)/1.25 var(--sc-font-display); }
.by span { color: var(--ink-2); font-weight: 400; }
.notes { margin-top: 28px; border-top: 1px solid var(--ink); padding-top: 12px; max-width: 34em; }
.notes h2 { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; }
.notes ol { margin: 8px 0 0; padding: 0; list-style: none; counter-reset: n; }
.notes li { counter-increment: n; display: grid; grid-template-columns: 30px 1fr; padding: 4px 0; }
.notes li::before { content: counter(n) "."; font: 600 var(--l2) var(--sc-font-display); }
.notes b { white-space: nowrap; }
.cta { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 26px; margin-top: 30px; }

.view-a { position: relative; margin: 0; height: 100%; min-height: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; }
.cgrid {
  position: absolute; inset: -2% -4%; z-index: 0;
  background-image:
    linear-gradient(var(--gridline) 1px, transparent 1px),
    linear-gradient(90deg, var(--gridline) 1px, transparent 1px);
  background-size: 40px 40px;
  -webkit-mask-image: radial-gradient(closest-side, #000 55%, transparent);
          mask-image: radial-gradient(closest-side, #000 55%, transparent);
  opacity: 0.8;
}
.plate { position: relative; z-index: 1; width: 560px; height: 560px; --u: 0.32; --co: 0; --cutop: 1; }
.plate > .photo, .plate > .section, .plate > .callouts, .plate-shadow { position: absolute; inset: 0; width: 100%; height: 100%; }
.plate-shadow {
  border-radius: 50%;
  box-shadow: 0 2px 4px hsl(236 40% 18% / 0.22), 14px 26px 44px -12px hsl(236 40% 18% / 0.42);
  clip-path: inset(-12% -12% -12% calc(var(--u) * 100%));
}
.photo { clip-path: inset(0 0 0 calc(var(--u) * 100%)); }
.section { clip-path: inset(0 calc((1 - var(--u)) * 100%) 0 0); overflow: hidden; }
.callouts { overflow: visible; opacity: var(--co); pointer-events: none; }
.cut { position: absolute; top: -5%; bottom: 0; left: calc(var(--u) * 100%); width: 0; opacity: var(--cutop); }
.cut-line { position: absolute; left: -30px; width: 60px; height: 100%; overflow: visible; }
.cut-line path { stroke: var(--ink); stroke-width: 2; stroke-dasharray: 26 6 4 6; vector-effect: non-scaling-stroke; fill: none; }
.cut-end { position: absolute; left: -3px; width: 6px; height: 34px; background: var(--ink); }
.cut-end.top { top: 0; }
.cut-end.bottom { bottom: 0; }
.cut-end i { position: absolute; top: 15px; right: 6px; width: 34px; height: 2px; background: var(--ink); }
.cut-end i::before { content: ""; position: absolute; left: -2px; top: -5px; width: 11px; height: 12px; background: var(--ink); clip-path: polygon(0 50%, 100% 0, 100% 100%); }
.cut-end b { position: absolute; right: 18px; top: -24px; font: 700 22px/1 var(--sc-font-display); }
.view-a { --px: 45px; }
.view-a .vlabel { position: relative; z-index: 1; width: 100%; max-width: 640px; margin-top: calc(var(--px) + 18px); }

/* ---------------------------------------------------------------- parts -- */
.two { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(28px, 5vw, 88px); align-items: end; }
.parts td:first-child, .parts th:first-child { width: 56px; text-align: center; font-family: var(--sc-font-display); font-weight: 600; }
.parts td:last-child { width: 30%; color: var(--ink-2); }
.parts tr.mine td:last-child { color: var(--ink); font-weight: 600; }
.parts tr.mine td:first-child { background: repeating-linear-gradient(45deg, transparent 0 5px, var(--gridline) 5px 6px); }
.ref-board .ref-img { aspect-ratio: 4 / 3; }
.ref-board .ref-img img { object-position: 58% 55%; }
.ref-board .note { margin-top: 18px; font-size: 16px; line-height: 1.5; padding-top: 12px; border-top: 1px solid var(--ink); max-width: 34em; }

/* -------------------------------------------------------------- detail B -- */
.b-grid { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 40px clamp(28px, 5vw, 88px); align-items: start; }
.b-text { grid-row: 1 / span 2; }
.b-text p { max-width: 36em; }
.vals { margin-top: 26px; }
.vals th { width: 64px; font: 600 var(--l2) var(--sc-font-display); font-style: italic; }
.vals td:nth-child(2) { white-space: nowrap; font-weight: 600; }
.vals td:last-child { color: var(--ink-2); font-size: 15px; }
.b-refs { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.chartB-dim { transition: none; }

/* ----------------------------------------------------------------- rev A -- */
.rev-act { padding-bottom: clamp(120px, 26vh, 300px); }   /* authored silence before Detail C */
.rev-grid { max-width: 980px; }
.rev { margin-top: 28px; font-size: clamp(17px, 1.4vw, 20px); line-height: 1.55; }
.rev td:first-child { width: 64px; text-align: center; font: 600 var(--l3) var(--sc-font-display); }
.rev td { padding: 12px 16px; }

/* ------------------------------------------------------------ detail C -- */
.peak {
  height: 100%; display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); grid-template-rows: auto 1fr;
  gap: 22px clamp(28px, 4vw, 72px); align-items: start;
  padding: calc(var(--top) + 26px) var(--pad) calc(var(--fr) + 18px);
}
.peak-text { grid-column: 1; grid-row: 1; }
.peak-text p { margin-top: 14px; max-width: 34em; }
.ctrl { grid-column: 1; grid-row: 2; align-self: start; }
.live { grid-column: 2; grid-row: 1 / span 2; margin: 0; align-self: center; }
.live .chart { height: min(54svh, 520px); }
.scale-head { display: flex; justify-content: space-between; align-items: baseline; }
.scale-head label { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; }
.scale-head output { font: 600 var(--l4)/1 var(--sc-font-display); font-variant-numeric: tabular-nums; }
.scale-body { position: relative; height: 72px; margin-top: 8px; }
.ruler { position: absolute; inset: 0; width: 100%; height: 100%; overflow: visible; }
.ruler text { font-family: var(--sc-font-display); }
#kp {
  position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: ew-resize;
  -webkit-appearance: none; appearance: none; background: transparent; touch-action: pan-y;
}
#kp::-webkit-slider-thumb { -webkit-appearance: none; width: 24px; height: 72px; }
#kp::-moz-range-thumb { width: 24px; height: 72px; border: 0; }
.scale-body:has(#kp:focus-visible) { outline: 2px dashed var(--red); outline-offset: 6px; }
.readouts { display: grid; grid-template-columns: 1fr 1fr; margin: 18px 0 0; border: 1px solid var(--ink); }
.readouts div { padding: 8px 12px; }
.readouts div + div { border-left: 1px solid var(--ink); }
.readouts dt { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; }
.readouts dd { margin: 2px 0 0; font: 600 var(--l3)/1.1 var(--sc-font-display); font-variant-numeric: tabular-nums; }
.readouts dd.bad { color: var(--red); }
.presets { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); margin-top: 18px; border: 1px solid var(--ink); }
.presets button {
  display: grid; gap: 2px; padding: 6px 6px 7px; background: none; border: 0; border-left: 1px solid var(--ink-3);
  color: var(--ink-2); cursor: pointer; font: 500 14px var(--sc-font-display); text-align: left; min-height: 64px;
  transition: background 140ms var(--ease), color 140ms var(--ease);
}
.presets button:first-child { border-left: 0; }
.presets button svg { width: 100%; height: 34px; overflow: visible; }
.presets button[aria-pressed="true"] { background: var(--paper-2); color: var(--ink); font-weight: 600; }
@media (hover: hover) and (pointer: fine) { .presets button:hover { background: var(--paper-2); color: var(--ink); } }
.slot { display: grid; margin-top: 12px; }
.redline, .revb { grid-area: 1 / 1; align-self: start; transition: opacity 220ms var(--ease); }
.redline { display: flex; gap: 10px; align-items: center; justify-content: flex-end; font: italic 600 var(--l2) var(--sc-font-display); color: var(--red); opacity: 0; }
.redline svg { width: 24px; height: 22px; flex: none; }
.revb { font-size: 16px; line-height: 1.5; padding: 8px 12px; border: 1px solid var(--ink); background: var(--paper); opacity: 0; }
.revb b { font: 700 var(--l1) var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; margin-right: 8px; }
.cloud { fill: none; stroke: var(--red); stroke-width: 2; transition: stroke-dashoffset 700ms var(--ease), opacity 200ms var(--ease); }

/* --------------------------------------------------------- details D, E -- */
.de-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(28px, 5vw, 88px); align-items: start; }
.de > p { margin-top: 16px; max-width: 36em; }
.de figure { margin: 26px 0 0; }
.ref-sm { max-width: 340px; }

/* -------------------------------------------------------------- results -- */
.res-grid { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: clamp(28px, 5vw, 88px); align-items: start; }
.res-figs { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }

/* ---------------------------------------------------------- title block -- */
.tb-act { padding-bottom: calc(var(--fr) + 56px); }
.tb { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border: 2.5px solid var(--ink); }
.tb > div { border-right: 1px solid var(--ink); border-bottom: 1px solid var(--ink); padding: 10px 14px 12px; min-width: 0; }
.tb > div:nth-child(4n) { border-right: 0; }
.tb > div.last { border-bottom: 0; }
.tb .k { display: block; font: 600 12px var(--sc-font-display); letter-spacing: 0.14em; text-transform: uppercase; color: var(--ink-2); }
.tb .v { display: block; margin-top: 2px; font: 500 var(--l2)/1.3 var(--sc-font-display); }
.tb-title { grid-column: 1 / 4; padding: 18px 20px 22px !important; }
.tb-title h2 { margin-top: 6px; font: 600 clamp(30px, 3.4vw, var(--l5))/1.04 var(--sc-font-display); text-wrap: balance; }
.tb-title p { margin-top: 14px; max-width: 42em; color: var(--ink-2); }
.tb-contact { grid-column: 4; border-right: 0 !important; display: flex; flex-direction: column; justify-content: space-between; gap: 16px; background: var(--ink); color: var(--paper); }
.tb-contact .k { color: #c9cbe6; }
.tb-contact a {
  display: flex; align-items: center; justify-content: space-between; gap: 10px; min-height: 56px; padding-top: 12px;
  border-top: 1px solid #6e72a8; color: var(--paper); text-decoration: none; font: 600 var(--l3)/1.1 var(--sc-font-display);
}
.tb-contact a svg { width: 28px; height: 12px; flex: none; transition: transform 160ms var(--ease); }
@media (hover: hover) and (pointer: fine) { .tb-contact a:hover svg { transform: translateX(4px); } }
.tb-contact a:focus-visible { outline-color: #ffb3ad; }
.src { margin-top: 18px; font-size: 14px; color: var(--ink-2); max-width: 60em; }

/* ------------------------------------------------------------ responsive -- */
@media (max-width: 1100px) {
  .bar-index { display: none; }
  .bar-here { display: block; margin-left: auto; }
}
@media (max-width: 860px) {
  :root { --fr: 10px; --bar: 46px; --gut: 16px; }
  .frame::before { inset: calc(-1 * var(--fr) + 4px); }
  .zx, .zy { display: none; }
  .bar { gap: 12px; padding-left: 12px; }
  .bar-here { display: none; }
  .bar-cta { margin-left: auto; height: 34px; padding: 0 12px; font-size: 14px; }

  .hero { grid-template-columns: 1fr; grid-template-rows: auto minmax(0, 1fr); gap: 14px; align-items: start; padding-top: calc(var(--top) + 14px); padding-bottom: calc(var(--fr) + 8px); }
  .hero h1 { font-size: clamp(30px, 8.4vw, 38px); }
  .by { margin-top: 8px; font-size: 16px; }
  .notes { margin-top: 14px; padding-top: 8px; }
  .notes li { grid-template-columns: 20px 1fr; padding: 1px 0; font-size: 15px; line-height: 1.4; }
  .notes li::before { font-size: 15px; }
  .cta { margin-top: 14px; gap: 2px 18px; }
  .cta .btn { min-height: 46px; width: 100%; justify-content: center; }
  .cta .lnk { padding: 8px 0; font-size: 16px; }
  .view-a { --px: 23px; }
  .view-a .vlabel span { font-size: 13px; }

  .two, .b-grid, .de-grid, .res-grid { grid-template-columns: 1fr; }
  .b-text { grid-row: auto; }
  .b-refs { grid-template-columns: 1fr 1fr; gap: 12px; }
  .tbl { font-size: 15px; }
  .tbl th, .tbl td { padding: 6px 8px; }
  .parts td:first-child, .parts th:first-child { width: 40px; }

  .peak { grid-template-columns: 1fr; grid-template-rows: auto auto auto; gap: 10px; padding-top: calc(var(--top) + 12px); align-content: start; }
  .peak-text, .ctrl, .live { grid-column: 1; grid-row: auto; }
  .peak-text .h2 { font-size: 26px; }
  .peak-text p { margin-top: 6px; font-size: 15px; line-height: 1.45; }
  .live { order: 2; align-self: start; }
  .ctrl { order: 3; }
  .live .chart { height: 27svh; }
  .live .vlabel { display: none; }
  .slot { margin-top: 6px; }
  .redline { font-size: 15px; justify-content: flex-start; }
  .revb { font-size: 13.5px; line-height: 1.4; padding: 6px 8px; }
  .scale-head output { font-size: 28px; }
  .scale-body { height: 72px; margin-top: 0; }
  .readouts { margin-top: 8px; }
  .readouts div { padding: 5px 10px; }
  .readouts dd { font-size: 19px; }
  .presets { margin-top: 8px; }
  .presets button { min-height: 52px; font-size: 13px; padding: 4px; }
  .presets button svg { height: 24px; }

  .tb { grid-template-columns: 1fr 1fr; }
  .tb > div, .tb > div:nth-child(4n) { border-right: 1px solid var(--ink); }
  .tb > div:nth-child(2n) { border-right: 0; }
  .tb-title, .tb-contact { grid-column: 1 / -1 !important; border-right: 0 !important; }
  .tb > div.last { border-bottom: 1px solid var(--ink); }
  .tb > div.last:nth-last-child(-n + 2) { border-bottom: 0; }
}
@media (max-width: 860px) { .res-figs { grid-template-columns: 1fr; } }
@media (max-width: 420px) {
  .b-refs { grid-template-columns: 1fr; }
  .bar-name { font-size: 12px; letter-spacing: 0.1em; }
}

/* reduced motion: static composition, no pinned travel */
.rm .act-hero { min-height: 100svh; }
.rm .act-hero [data-sc-stage], .rm .act-peak [data-sc-stage] { position: relative; height: auto; min-height: 100svh; }
.rm .cloud, .rm .bar-index a::after, .rm .redline, .rm .revb { transition: none; }