/* Layout concept: dark engineering hero, light reading bands; one motif (wastewater in, water and salts out) repeated. */
:root {
  --navy: #0A0E27;
  --navy-2: #141A3D;
  --navy-line: #262E5A;
  --blue: #0066CC;
  --blue-lit: #4DA3FF;
  --ink: #0F1430;
  --ink-2: #4A5372;
  --paper: #F3F6FB;
  --white: #FFFFFF;
  --line: #DCE3EF;
  --salt: #E9E1CF;
  --font-body: 'IBM Plex Sans', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, Menlo, Consolas, monospace;
  --gutter: clamp(16px, 4vw, 32px);
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; }
body {
  margin: 0;
  background: var(--white);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--blue); }
h1, h2, h3, h4 { font-weight: 600; line-height: 1.15; letter-spacing: -0.015em; text-wrap: balance; margin: 0; }
p { margin: 0; }
:focus-visible { outline: 3px solid var(--blue-lit); outline-offset: 3px; border-radius: 2px; }

.wrap { width: 100%; max-width: 1120px; margin-inline: auto; padding-inline: var(--gutter); }
.eyebrow { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--blue); margin-bottom: 14px; }
.on-dark .eyebrow, .band-dark .eyebrow { color: var(--blue-lit); }
.lede { font-size: 1.125rem; color: var(--ink-2); max-width: 62ch; }
.band-dark .lede { color: #B9C2E0; }

/* Header */
.site-header {
  position: sticky; top: env(safe-area-inset-top, 0px); z-index: 50;
  background: rgba(10, 14, 39, 0.94); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--navy-line);
}
.bar { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 10px; color: #fff; text-decoration: none; font-weight: 600; letter-spacing: -0.01em; }
.brand svg { width: 22px; height: 28px; }
.nav { display: flex; align-items: center; gap: 24px; }
.nav a:not(.btn) { color: #C9D1EA; text-decoration: none; font-size: 0.9375rem; padding: 6px 0; border-bottom: 2px solid transparent; }
.nav a:not(.btn):hover, .nav a[aria-current="page"] { color: #fff; border-bottom-color: var(--blue-lit); }
.nav-toggle { display: none; background: transparent; color: #fff; border: 1px solid var(--navy-line); border-radius: 6px; padding: 8px 14px; font: inherit; font-size: 0.875rem; cursor: pointer; }
@media (max-width: 780px) {
  .nav-toggle { display: inline-block; }
  .nav { width: 100%; flex-direction: column; align-items: flex-start; gap: 4px; padding-bottom: 16px; }
  .js .nav { display: none; }
  .js .nav.open { display: flex; }
  .nav .btn { margin-top: 8px; }
}

/* Buttons */
.btn {
  display: inline-block; background: var(--blue); color: #fff; text-decoration: none; font-weight: 500;
  padding: 13px 22px; border-radius: 6px; border: 1px solid var(--blue); font-size: 1rem; cursor: pointer; font-family: inherit; line-height: 1.2;
}
.btn:hover { background: #0057AD; border-color: #0057AD; }
.btn-sm { padding: 9px 16px; font-size: 0.875rem; }
.btn-ghost { background: transparent; color: #fff; border-color: #4A5590; }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.08); border-color: #7C88C4; }
.btn-line { background: transparent; color: var(--blue); border-color: var(--blue); }
.btn-line:hover { background: var(--blue); color: #fff; }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }

/* Bands */
.band { padding-block: clamp(56px, 9vw, 104px); }
.band-dark { background: var(--navy); color: #fff; }
.band-dark2 { background: var(--navy-2); color: #fff; }
.band-paper { background: var(--paper); }
.band-white { background: var(--white); }
.band-head { max-width: 760px; margin-bottom: clamp(32px, 5vw, 56px); }
.band-head h2 { font-size: clamp(1.75rem, 3.6vw, 2.5rem); }
.band-head p { margin-top: 16px; }

/* Hero */
.hero { padding-block: clamp(56px, 9vw, 112px); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr); gap: clamp(32px, 6vw, 72px); align-items: center; }
.hero h1 { font-size: clamp(2.25rem, 5.4vw, 3.9rem); letter-spacing: -0.025em; }
.hero .lede { margin-top: 22px; }
.hero-simple .hero-grid { grid-template-columns: minmax(0, 1fr); }
.hero-simple h1 { font-size: clamp(2rem, 4.6vw, 3.25rem); max-width: 20ch; }
@media (max-width: 900px) { .hero-grid { grid-template-columns: minmax(0, 1fr); } }

/* Mass balance card */
.balance { background: var(--navy-2); border: 1px solid var(--navy-line); border-radius: 10px; padding: clamp(20px, 3vw, 32px); }
.balance .tag { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; color: #93A0D0; }
.balance .in { display: flex; align-items: baseline; gap: 10px; margin: 14px 0 20px; }
.balance .in b { font-family: var(--font-mono); font-size: 2.5rem; font-weight: 500; line-height: 1; }
.balance .in span { color: #B9C2E0; }
.bar-track { display: flex; height: 56px; border-radius: 6px; overflow: hidden; background: var(--navy-line); }
.bar-water { flex: 0 0 90%; background: var(--blue); animation: fill 1.4s cubic-bezier(.2, .7, .2, 1) both; transform-origin: left; }
.bar-salt { flex: 1 1 auto; background: var(--salt); }
@keyframes fill { from { transform: scaleX(0.05); } to { transform: scaleX(1); } }
.bar-legend { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 12px 20px; margin-top: 16px; font-size: 0.9375rem; }
.bar-legend .k { display: flex; gap: 8px; align-items: center; color: #DCE3F7; }
.bar-legend i { width: 12px; height: 12px; border-radius: 2px; display: inline-block; flex: none; }
.bar-legend .v { font-family: var(--font-mono); text-align: right; color: #fff; }
.balance .zero { margin-top: 20px; padding-top: 16px; border-top: 1px solid var(--navy-line); display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; color: #DCE3F7; }
.balance .zero b { font-family: var(--font-mono); font-weight: 500; color: #fff; }
.balance small { display: block; margin-top: 14px; color: #93A0D0; font-size: 0.8125rem; line-height: 1.45; }

/* Three-column statements */
.cols3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: clamp(24px, 4vw, 48px); }
.cols3 h3 { font-size: 1.25rem; margin-bottom: 10px; }
.cols3 p { color: var(--ink-2); }
.cols3 > div { border-top: 2px solid var(--ink); padding-top: 18px; }
@media (max-width: 860px) { .cols3 { grid-template-columns: minmax(0, 1fr); } }

/* Stats */
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; border-top: 1px solid var(--navy-line); }
.stat { padding: 28px 24px 8px 0; }
.stat + .stat { padding-left: 24px; border-left: 1px solid var(--navy-line); }
.stat .n { font-family: var(--font-mono); font-size: clamp(2rem, 3.6vw, 2.75rem); font-weight: 500; line-height: 1; color: #fff; font-variant-numeric: tabular-nums; }
.stat .l { margin-top: 12px; font-weight: 500; }
.stat .q { margin-top: 6px; font-size: 0.875rem; color: #93A0D0; line-height: 1.45; }
@media (max-width: 900px) {
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat:nth-child(3) { padding-left: 0; border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--navy-line); margin-top: 20px; }
}
@media (max-width: 480px) {
  .stats { grid-template-columns: minmax(0, 1fr); }
  .stat, .stat + .stat { padding-left: 0; border-left: 0; }
  .stat + .stat { border-top: 1px solid var(--navy-line); margin-top: 20px; }
}

/* Treatment train */
.train { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 0; list-style: none; padding: 0; margin: 0; }
.stage { position: relative; padding: 20px 18px 20px; border: 1px solid var(--line); background: var(--white); margin-left: -1px; display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.stage:first-child { margin-left: 0; border-radius: 8px 0 0 8px; }
.stage:last-child { border-radius: 0 8px 8px 0; }
.stage .k { font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-2); }
.stage h3 { font-size: 1.125rem; }
.stage p { font-size: 0.875rem; color: var(--ink-2); }
.stage .out { margin-top: auto; padding-top: 12px; font-family: var(--font-mono); font-size: 0.75rem; color: var(--blue); }
.stage.in { background: var(--paper); }
.stage.opt { border-style: dashed; background: transparent; }
.stage.end { background: var(--navy); border-color: var(--navy); }
.stage.end h3, .stage.end .k { color: #fff; }
.stage.end p { color: #B9C2E0; }
.stage.end .out { color: var(--salt); }
.stage:not(:last-child)::after {
  content: ""; position: absolute; right: -7px; top: 50%; width: 12px; height: 12px; margin-top: -6px;
  background: var(--white); border-top: 1px solid var(--ink); border-right: 1px solid var(--ink); transform: rotate(45deg); z-index: 2;
}
.stage.in:not(:last-child)::after { background: var(--paper); }
.train.train-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.train-note { margin-top: 20px; color: var(--ink-2); font-size: 0.9375rem; max-width: 70ch; }
@media (max-width: 900px) {
  .train, .train.train-4 { grid-template-columns: minmax(0, 1fr); }
  .stage { margin-left: 0; margin-top: -1px; border-radius: 0 !important; }
  .stage:first-child { border-radius: 8px 8px 0 0 !important; margin-top: 0; }
  .stage:last-child { border-radius: 0 0 8px 8px !important; }
  .stage:not(:last-child)::after { right: auto; left: 28px; top: auto; bottom: -7px; margin-top: 0; transform: rotate(135deg); }
}

/* Partner cards */
.partners { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.partner { background: var(--white); border: 1px solid var(--line); border-radius: 8px; padding: 28px; display: flex; flex-direction: column; gap: 10px; min-width: 0; }
.partner .role { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--blue); }
.partner h3 { font-size: 1.5rem; }
.partner .prod { font-weight: 500; }
.partner p { color: var(--ink-2); font-size: 0.9375rem; }
.partner a.more { margin-top: auto; padding-top: 10px; font-weight: 500; text-decoration: none; }
.partner a.more:hover { text-decoration: underline; }
@media (max-width: 900px) { .partners { grid-template-columns: minmax(0, 1fr); } }
.partners { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (max-width: 900px) { .partners { grid-template-columns: minmax(0, 1fr); } }
.strategic { margin-top: 20px; display: grid; grid-template-columns: auto minmax(0, 1fr); gap: 24px; align-items: center; padding: 20px 28px; border: 1px solid var(--line); border-radius: 8px; background: var(--white); }
.strategic .role { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-2); }
.strategic h3 { font-size: 1.25rem; margin: 2px 0 4px; }
.strategic p { color: var(--ink-2); font-size: 0.9375rem; }
.strategic .more { display: inline-block; margin-top: 6px; font-weight: 500; text-decoration: none; }
.strategic .ph.logo { width: 180px; }
@media (max-width: 640px) { .strategic { grid-template-columns: minmax(0, 1fr); } }

/* Sectors */
.sectors { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; }
.sector { border-top: 2px solid var(--blue); padding-top: 16px; }
.sector h3 { font-size: 1.125rem; margin-bottom: 8px; }
.sector p { color: var(--ink-2); font-size: 0.9375rem; }
@media (max-width: 980px) { .sectors { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 520px) { .sectors { grid-template-columns: minmax(0, 1fr); } }

/* Feature split (image + text) */
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(28px, 5vw, 64px); align-items: center; }
.split.flip .split-media { order: 2; }
@media (max-width: 860px) { .split { grid-template-columns: minmax(0, 1fr); } .split.flip .split-media { order: 0; } }
.split h2 { font-size: clamp(1.625rem, 3.2vw, 2.25rem); }
.split .lede { margin-top: 16px; }
.facts { list-style: none; padding: 0; margin: 24px 0 0; display: grid; gap: 0; }
.facts li { display: flex; justify-content: space-between; gap: 16px; padding: 12px 0; border-top: 1px solid var(--line); }
.facts li:last-child { border-bottom: 1px solid var(--line); }
.facts .fk { color: var(--ink-2); }
.facts .fv { font-family: var(--font-mono); font-size: 0.9375rem; text-align: right; }
.band-dark .facts li, .band-dark2 .facts li { border-color: var(--navy-line); }
.band-dark .facts .fk, .band-dark2 .facts .fk { color: #B9C2E0; }

/* Image placeholders: the picture replaces the label once the file exists in /images */
.ph { position: relative; margin: 0; aspect-ratio: 4 / 3; max-width: 100%; border-radius: 8px; overflow: hidden; border: 1px solid var(--line);
  background: repeating-linear-gradient(135deg, #E7EDF7 0 14px, #EEF2F9 14px 28px); display: grid; place-items: center; }
.ph::after { content: "Add photo: " attr(data-label); font-family: var(--font-mono); font-size: 0.75rem; color: var(--ink-2); padding: 0 16px; text-align: center; }
.ph img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: 1; }
.band-dark .ph, .band-dark2 .ph { border-color: var(--navy-line); background: repeating-linear-gradient(135deg, #1A2148 0 14px, #1E2650 14px 28px); }
.band-dark .ph::after, .band-dark2 .ph::after { color: #93A0D0; }
.ph.logo { aspect-ratio: 16 / 7; max-width: 220px; }
.ph.logo img { object-fit: contain; padding: 12px; background: #fff; }

/* Pending-content notes (delete the element once confirmed) */
.todo { border: 1px dashed #B87B00; background: #FFF7E6; color: #5C3D00; border-radius: 6px; padding: 14px 16px; font-size: 0.9375rem; }
.todo b { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; display: block; margin-bottom: 4px; }

/* Sub navigation */
.subnav { background: var(--white); border-bottom: 1px solid var(--line); position: sticky; top: calc(64px + env(safe-area-inset-top, 0px)); z-index: 40; }
.subnav .wrap { display: flex; gap: 24px; overflow-x: auto; white-space: nowrap; }
.subnav a { color: var(--ink-2); text-decoration: none; font-size: 0.9375rem; padding: 14px 0; border-bottom: 2px solid transparent; }
.subnav a:hover { color: var(--ink); border-bottom-color: var(--blue); }

/* Tables */
.table-scroll { overflow-x: auto; border: 1px solid var(--line); border-radius: 8px; background: var(--white); }
table.spec { width: 100%; border-collapse: collapse; min-width: 640px; font-size: 0.9375rem; }
.spec th, .spec td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--line); vertical-align: top; }
.spec thead th { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-2); background: var(--paper); }
.spec tbody th { font-weight: 500; width: 22%; color: var(--ink-2); }
.spec tr:last-child th, .spec tr:last-child td { border-bottom: 0; }
.spec td { font-variant-numeric: tabular-nums; }
.fineprint { margin-top: 14px; font-size: 0.8125rem; color: var(--ink-2); max-width: 80ch; }

/* Process strip (CEE) */
.flow { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 24px 0 0; }
.flow li { font-family: var(--font-mono); font-size: 0.8125rem; padding: 8px 12px; border: 1px solid var(--line); border-radius: 999px; background: var(--white); }
.flow li + li::before { content: none; }

/* Chips */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.chip { font-family: var(--font-mono); font-size: 0.8125rem; padding: 6px 12px; border: 1px solid var(--navy-line); border-radius: 999px; color: #DCE3F7; }

/* Contact */
.contact-grid { display: grid; grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr); gap: clamp(28px, 5vw, 64px); }
@media (max-width: 860px) { .contact-grid { grid-template-columns: minmax(0, 1fr); } }
.contact-grid h2 { font-size: clamp(1.75rem, 3.4vw, 2.5rem); }
.details { list-style: none; padding: 0; margin: 28px 0 0; display: grid; gap: 14px; }
.details li { display: grid; gap: 2px; }
.details .dk { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; color: #93A0D0; }
.details a { color: #fff; }
form.card { background: var(--white); color: var(--ink); border-radius: 10px; padding: clamp(20px, 3vw, 32px); display: grid; gap: 16px; }
.field { display: grid; gap: 6px; min-width: 0; }
.field-row { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
@media (max-width: 560px) { .field-row { grid-template-columns: minmax(0, 1fr); } }
label { font-size: 0.875rem; font-weight: 500; }
input, select, textarea { font: inherit; color: var(--ink); background: var(--white); border: 1px solid #B9C4DA; border-radius: 6px; padding: 11px 12px; width: 100%; min-width: 0; }
textarea { min-height: 120px; resize: vertical; }
input:focus, select:focus, textarea:focus { outline: 3px solid var(--blue-lit); outline-offset: 1px; border-color: var(--blue); }
.form-status { font-size: 0.9375rem; min-height: 1.4em; }
.form-status.ok { color: #0B6B3A; }
.form-status.err { color: #A3261A; }
.hp { position: absolute; left: -9999px; }

/* Footer */
.site-footer { background: var(--navy); color: #B9C2E0; padding-block: 40px calc(40px + env(safe-area-inset-bottom, 0px)); border-top: 1px solid var(--navy-line); font-size: 0.9375rem; }
.foot { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 24px; }
.foot a { color: #DCE3F7; text-decoration: none; margin-right: 20px; }
.foot a:hover { text-decoration: underline; }
.foot .legal { flex: 1 1 100%; color: #7C88B4; font-size: 0.8125rem; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .bar-water { animation: none; }
}

/* ---- Technology deep-dive additions ---- */
:root { --teal: #0E8F8B; --amber: #B36B00; }
.diagram { margin: 28px 0 0; background: var(--white); border: 1px solid var(--line); border-radius: 8px; padding: 16px; overflow-x: auto; }
.diagram svg { display: block; width: 100%; min-width: 680px; height: auto; }
.diagram figcaption { margin-top: 12px; font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.04em; color: var(--ink-2); }
.dg-line { stroke: #0F1430; stroke-width: 2; fill: none; }
.dg-water { stroke: #0066CC; stroke-width: 3.5; fill: none; }
.dg-air { stroke: #0066CC; stroke-width: 1.6; fill: none; }
.dg-teal { stroke: #0E8F8B; stroke-width: 2.5; fill: none; }
.dg-hot { stroke: #B36B00; stroke-width: 2.5; fill: none; }
.dg-box { fill: #F3F6FB; stroke: #0F1430; stroke-width: 1.5; }
.dg-blue { fill: #DCEBFA; stroke: #0066CC; stroke-width: 1.5; }
.dg-warm { fill: #FFF1DB; stroke: #B36B00; stroke-width: 1.5; }
.dg-t { font-family: var(--font-body); font-size: 14px; fill: #0F1430; }
.dg-s { font-family: var(--font-mono); font-size: 11.5px; fill: #4A5372; }
.dg-b { font-weight: 600; }

.metrics { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); border: 1px solid var(--line); border-radius: 8px; background: var(--white); overflow: hidden; }
.metric { padding: 18px 20px; border-left: 1px solid var(--line); }
.metric:first-child { border-left: 0; }
.metric .n { font-family: var(--font-mono); font-size: 1.75rem; font-weight: 500; line-height: 1.1; font-variant-numeric: tabular-nums; }
.metric .n small { font-size: 0.875rem; color: var(--ink-2); }
.metric .l { margin-top: 6px; font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-2); }
.checks { list-style: none; padding: 0; margin: 20px 0 0; display: grid; gap: 10px; }
.checks li { position: relative; padding-left: 26px; }
.checks li::before { content: "\2713"; position: absolute; left: 0; color: var(--blue); font-weight: 600; }
.band-dark .checks li::before { color: var(--blue-lit); }
.proofline { margin-top: 16px; font-family: var(--font-mono); font-size: 0.8125rem; color: var(--ink-2); line-height: 1.5; }
.stack { display: grid; gap: 20px; min-width: 0; }

.compare2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin-top: 28px; }
@media (max-width: 700px) { .compare2 { grid-template-columns: minmax(0, 1fr); } }
.compare2 > div { border: 1px solid var(--line); border-radius: 8px; padding: 20px 24px; background: var(--white); }
.compare2 .hl { border-color: var(--blue); background: #F1F7FE; }
.compare2 h3 { font-size: 1.0625rem; margin-bottom: 6px; }
.compare2 p { color: var(--ink-2); font-size: 0.9375rem; }

.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 20px 24px; margin-top: 32px; }
.features > div { border-top: 2px solid var(--blue); padding-top: 14px; }
.features h3 { font-size: 1rem; margin-bottom: 6px; }
.features p { font-size: 0.9375rem; color: var(--ink-2); }

.problems { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
@media (max-width: 800px) { .problems { grid-template-columns: minmax(0, 1fr); } }
.problem { border: 1px solid var(--line); border-radius: 8px; padding: 24px; background: var(--white); display: grid; gap: 14px; align-content: start; }
.problem .ptag { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--amber); }
.problem h3 { font-size: 1.25rem; }
.problem .ans { border-left: 3px solid var(--blue); padding-left: 14px; color: var(--ink-2); font-size: 0.9375rem; }
.problem .ans b { display: block; font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--blue); font-weight: 500; margin-bottom: 4px; }

.pills { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }
.pill { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; padding: 7px 14px; border-radius: 999px; background: var(--blue); color: #fff; }
.steps { list-style: none; padding: 0; margin: 0; display: grid; gap: 0; }
.steps li { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 4px 12px; padding: 18px 0; border-top: 1px solid var(--navy-line); }
.steps li:last-child { border-bottom: 1px solid var(--navy-line); }
.steps .sn { font-family: var(--font-mono); color: var(--blue-lit); grid-row: span 2; }
.steps b { font-weight: 600; font-size: 1.0625rem; }
.steps span.d { color: #B9C2E0; }

.callout { margin-top: 28px; padding: 18px 22px; background: #E7EEF8; border-left: 3px solid var(--blue); border-radius: 0 6px 6px 0; }
.callout b { display: block; font-family: var(--font-mono); font-size: 0.6875rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--blue); font-weight: 500; margin-bottom: 4px; }
.spec .hl { background: #EEF5FD; }
.spec thead th.hl { color: var(--blue); }
.spec td.dim { color: var(--ink-2); }
.pill-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0 0; }
.pill-row span { font-family: var(--font-mono); font-size: 0.8125rem; padding: 6px 12px; border: 1px solid var(--line); border-radius: 999px; background: var(--white); }
.sector .res { display: block; margin-top: 8px; font-weight: 500; color: var(--ink); font-size: 0.9375rem; }
.sector .mo { display: block; margin-top: 4px; font-family: var(--font-mono); font-size: 0.75rem; color: var(--blue); }
.band-dark .sector { border-top-color: var(--blue-lit); }
.band-dark .sector p { color: #B9C2E0; }
.band-dark .sector .res { color: #fff; }
.band-dark .sector .mo { color: var(--blue-lit); }