.intro-block{position:relative;isolation:isolate;border-bottom:1px solid var(--line)}.intro-copy,.lookup-sheet{position:relative;z-index:1}
.guide-library{padding:25px 0 54px;border-top:1px solid var(--line)}.guide-library h2{font:500 clamp(1.8rem,3vw,2.7rem)/1.1 var(--serif);margin:0 0 19px}.guide-library-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:0 28px}.guide-library-card{display:flex;gap:13px;align-items:flex-start;padding:18px 0;border-top:1px solid var(--line);color:var(--ink);text-decoration:none}.guide-library-card strong{display:block;font:500 1.12rem/1.2 var(--serif)}.guide-library-card small{display:block;margin-top:5px;color:var(--muted);font-size:.76rem;line-height:1.45}.guide-library-card .guide-icon{flex:0 0 32px;height:32px;display:grid;place-items:center;border:1px solid var(--line);border-radius:50%;color:var(--blue)}.guide-library-card svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}.guide-library-card:hover strong{color:var(--rust);text-decoration:underline}
@media(max-width:620px){.guide-library-grid{grid-template-columns:1fr}}
.guide-shell{max-width:960px;margin:auto;padding:52px 28px 80px}.breadcrumbs{font-size:.78rem;color:var(--muted);margin-bottom:28px}.breadcrumbs a{color:var(--blue)}.guide-shell h1{font:500 clamp(2.5rem,5.6vw,4.3rem)/1.03 var(--serif);letter-spacing:-.045em;margin:12px 0 18px}.guide-intro{font-size:1.12rem;color:var(--muted);max-width:68ch}.guide-shell h2{font:500 1.7rem/1.2 var(--serif);margin:38px 0 12px}.guide-shell p,.guide-shell li{max-width:74ch;color:var(--ink)}.guide-shell li{margin:7px 0}.guide-callout{background:#eceae2;border:1px solid var(--line);padding:18px 20px;margin:24px 0}.guide-callout strong{color:var(--blue)}.guide-table-wrap{overflow-x:auto;margin:22px 0}.guide-table{border-collapse:collapse;width:100%;min-width:560px;font-size:.83rem}.guide-table th,.guide-table td{text-align:left;padding:10px 12px;border:1px solid var(--line);vertical-align:top}.guide-table th{background:var(--blue);color:white;font-size:.68rem;text-transform:uppercase;letter-spacing:.04em}.guide-table td{background:#fffefa}.method-small{font-size:.7rem!important;border-top:1px solid var(--line);margin-top:42px;padding-top:15px;color:var(--muted)!important}
.lookup-sheet{overflow:hidden}.filter-token{position:absolute;z-index:0;width:clamp(95px,15vw,160px);height:auto;right:1.15rem;top:1rem;mix-blend-mode:multiply;opacity:.94;pointer-events:none;filter:drop-shadow(0 12px 14px rgba(24,40,31,.12))}.sheet-heading,.lookup-sheet>h2,.lookup-sheet>label,.lookup-sheet form,.lookup-sheet>.help,.lookup-sheet>.answer,.lookup-sheet>.lookup-foot{position:relative;z-index:1}.lookup-sheet>h2{max-width:calc(100% - 130px)}.lookup-sheet>label{display:block;max-width:calc(100% - 120px)}.guide-icon-img{width:60px;height:60px;flex:0 0 60px;object-fit:contain}.market-scope{font-size:.82rem;color:var(--muted);margin:0 0 10px}
@media(max-width:620px){.filter-token{width:88px;right:12px;top:12px}.lookup-sheet>h2,.lookup-sheet>label{max-width:calc(100% - 80px)}.guide-icon-img{width:54px;height:54px;flex-basis:54px}}

.filter-token{mix-blend-mode:normal;opacity:1;border-radius:4px}

/* Filter Ledger registry direction: cool blue-gray surfaces and local system typography. */
:root{
  --paper:#edf3f5;
  --sheet:#ffffff;
  --ink:#18303a;
  --muted:#52666e;
  --line:#c8d7dc;
  --blue:#0d6478;
  --blue-soft:#dcebee;
  --rust:#a94732;
  --rust-soft:#f6e8e1;
  --olive:#4c6b61;
  --sans:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  --display:ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  /* Existing page templates call their display token --serif; it now aliases the sans registry face. */
  --serif:var(--display);
  --mono:ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
}

.intro-block{
  background:
    linear-gradient(rgba(13,100,120,.035) 1px,transparent 1px) 0 0/32px 32px,
    linear-gradient(90deg,rgba(13,100,120,.035) 1px,transparent 1px) 0 0/32px 32px,
    linear-gradient(135deg,#f7fafb 0%,#e7f0f2 100%);
  border-bottom-color:var(--line);
}
.lookup-sheet{background:var(--sheet);border-color:var(--line);box-shadow:0 4px 0 #dce6e8,0 18px 38px rgba(24,48,58,.08)}
.lookup-sheet:before,.lookup-sheet:after{background:var(--line)}
.table-wrap{background:#f7fafb;border-color:var(--line)}
thead th{background:#e1ecef;color:#385660}
.evidence-section{background:#e4edef;border-color:#c8d7dc}
.evidence-columns article{border-color:#bdced3}
.guide-callout{background:#e5eff1;border-color:var(--line);border-left:3px solid var(--blue)}
.guide-table td{background:#fbfdfe}
.answer{background:#f1f7f8}
.answer.unresolved{background:var(--rust-soft);border-color:#dfc2b8}
.lookup-sheet input,.filters select,.guide-table td{color:var(--ink)}
.intro-copy h1,.guide-shell h1{font-family:var(--display);font-weight:700;letter-spacing:-.045em}
.section-title h2,.evidence-heading h2,.questions h2,.guide-shell h2,.lookup-sheet h2{font-family:var(--display);font-weight:650}

/* Keep market selection outside primary navigation and give the header a reliable wrap contract. */
.masthead{
  min-height:0;
  height:auto;
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:12px;
  padding-block:14px;
}
.masthead nav{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:flex-start;
  gap:8px 16px;
  margin-left:0;
  min-width:0;
}
.masthead nav>a{min-width:0}
.masthead>.locale-switch{
  grid-column:1;
  justify-self:start;
  max-width:100%;
  margin:0;
  padding:0;
}
.masthead>.locale-switch span{color:var(--muted)}
.masthead>.locale-switch a{white-space:nowrap}
.skip{
  position:fixed;
  left:1rem;
  top:-5rem;
  z-index:100;
  border:1px solid var(--blue);
  background:var(--sheet);
  color:var(--ink);
  box-shadow:0 3px 12px rgba(24,48,58,.16);
}
.skip:focus,.skip:focus-visible{top:1rem}

@media(min-width:981px){
  .masthead{grid-template-columns:auto minmax(0,1fr);grid-template-rows:auto auto;gap:5px 26px;padding-block:8px}
  .wordmark{grid-column:1;grid-row:1}
  .masthead nav{grid-column:2;grid-row:1;justify-content:flex-end;gap:8px 15px}
  .masthead>.locale-switch{grid-column:1/-1;grid-row:2;justify-self:end}
}
@media(max-width:620px){
  .masthead{padding-block:12px;gap:9px}
  .masthead nav{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:3px 14px}
  .masthead nav>a{display:block;overflow-wrap:anywhere;padding:5px 0;font-size:.78rem;line-height:1.35}
  .masthead nav>a:first-child{display:block}
  .masthead>.locale-switch{width:100%;align-items:flex-start;gap:6px 8px}
  .masthead>.locale-switch span{flex-basis:100%}
}

html{scroll-behavior:auto}
button{transition:transform 140ms cubic-bezier(.23,1,.32,1)}
button:active:not(:disabled){transform:scale(.98)}
@media(prefers-reduced-motion:reduce){button{transition:none}button:active:not(:disabled){transform:none}}

/* The four field guides share an asymmetric two-column shelf; the odor guide has its own editorial checklist. */
.guide-library-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:0 44px}
.guide-symbol{width:60px;height:60px;flex:0 0 60px;border:1px solid var(--line);border-radius:50%;display:grid;place-items:center;background:#e5eff1;color:var(--rust);font-family:var(--display);font-size:1.8rem;font-weight:700}
.maintenance-stack{display:grid;gap:18px;margin:2rem 0 3rem}
.maintenance-card{padding:24px 28px;border:1px solid var(--line);border-top:3px solid var(--rust);background:#fbfdfe}
.maintenance-card h2{margin:.25rem 0 1.2rem}
.maintenance-card dl{display:grid;gap:10px;margin:0}
.maintenance-card dl div{display:grid;grid-template-columns:minmax(150px,.34fr) 1fr;gap:18px;padding:13px 0;border-top:1px solid var(--line)}
.maintenance-card dt{font-weight:700}
.maintenance-card dd{margin:0;line-height:1.65}
.maintenance-boundary{padding:24px 28px;background:#e5eff1;border-left:3px solid var(--rust)}
.maintenance-boundary li{margin:.55rem 0}
.maintenance-guide a:focus-visible{outline:3px solid var(--rust);outline-offset:3px}
@media(max-width:620px){.guide-symbol{width:54px;height:54px;flex-basis:54px}.maintenance-card,.maintenance-boundary{padding:20px 18px}.maintenance-card dl div{grid-template-columns:1fr;gap:5px}}
.odor-alert{margin:28px 0;padding:18px 20px;background:#f7ebe5;border:1px solid #dfc5b7;border-left:4px solid var(--rust);max-width:78ch;line-height:1.55}
.odor-alert strong{color:#713a2b}
.odor-sequence{list-style:none;padding:0;margin:18px 0 42px;counter-reset:odor-step}
.odor-sequence>li{display:grid;grid-template-columns:52px minmax(0,1fr);gap:18px;padding:20px 0;border-top:1px solid var(--line)}
.odor-sequence>li:last-child{border-bottom:1px solid var(--line)}
.odor-index{font:600 .76rem/1 var(--mono);color:var(--blue);border:1px solid var(--line);border-radius:50%;width:40px;height:40px;display:grid;place-items:center}
.odor-sequence h3,.maker-guidance h3{font-size:1.12rem;line-height:1.25;margin:0 0 9px;color:var(--ink)}
.odor-sequence p{margin:8px 0;overflow-wrap:anywhere}
.odor-sequence a,.maker-guidance a{color:var(--blue);text-underline-offset:3px}
.maker-guidance{border-top:1px solid var(--line);padding-top:6px}
.maker-guidance-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:28px}
.maker-guidance article{border-top:2px solid var(--blue);padding:16px 0 0;min-width:0}
.maker-guidance article p{font-size:.9rem;line-height:1.55;overflow-wrap:anywhere}
.maker-guidance article a{font-size:.82rem;font-weight:600}
.guide-library-card:focus-visible,.odor-guide a:focus-visible{outline:3px solid var(--rust);outline-offset:3px;border-radius:2px}
@media(max-width:760px){.guide-library-grid,.maker-guidance-grid{grid-template-columns:1fr;gap:0 20px}.maker-guidance-grid{gap:20px}.odor-sequence>li{grid-template-columns:40px minmax(0,1fr);gap:12px}.odor-index{width:34px;height:34px}}

.sensor-signal-grid,.sensor-model-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:20px 0 32px}
.sensor-signal-grid article,.sensor-model-card,.sensor-boundary{min-width:0;padding:22px;border:1px solid var(--line);background:#fbfdfe}
.sensor-signal-grid article{border-top:3px solid var(--blue)}
.sensor-model-card{border-top:3px solid var(--rust)}
.sensor-signal-grid h3,.sensor-model-card h3{font:650 1.22rem/1.2 var(--display);margin:8px 0 12px;color:var(--blue)}
.sensor-model-card ul{padding-left:20px}
.sensor-model-card .source-note{padding-top:14px;border-top:1px solid var(--line);font-size:.8rem}
.sensor-model-card a,.sensor-boundary a,.sensor-evidence a{color:var(--blue);text-underline-offset:3px}
.air-quality-guide a:focus-visible{outline:3px solid var(--rust);outline-offset:3px;border-radius:2px}
.sensor-evidence{margin-top:36px;padding-top:6px;border-top:1px solid var(--line)}
@media(max-width:760px){.sensor-signal-grid,.sensor-model-grid{grid-template-columns:1fr}.sensor-signal-grid article,.sensor-model-card,.sensor-boundary{padding:19px}}

/* iOS zooms on focus below 16px; all lookup and filter controls stay at 16px. */
.filters select,.serial-gate input,.lookup-sheet input{font-size:max(16px,1rem)}
/* The evidence notes repeat the index for no-JS and deep links; keep them one collapsed block. */
.all-records>summary{cursor:pointer;padding:12px 0;font-weight:600;color:var(--blue)}
.record-evidence{content-visibility:auto;contain-intrinsic-size:auto 600px}
.answer .candidate-match .model-link{min-height:44px;text-align:left}
@media(max-width:620px){
  /* Search in the first viewport: one scrolling nav row, shorter hero copy. */
  .masthead nav{display:flex;flex-wrap:nowrap;overflow-x:auto;gap:0 18px;scrollbar-width:none}
  .masthead nav>a{flex:0 0 auto;padding:10px 0}
  .intro-block{padding-top:20px;gap:18px}
  .intro-copy h1{font-size:clamp(1.7rem,7.5vw,2.2rem);line-height:1.05}
  .intro-copy .deck,.intro-copy .last-checked{display:none}
}