@font-face{font-family:Manrope;src:url('/assets/fonts/manrope-latin-400-normal.woff2') format('woff2');font-display:swap;font-weight:400}
@font-face{font-family:Manrope;src:url('/assets/fonts/manrope-latin-500-normal.woff2') format('woff2');font-display:swap;font-weight:500}
@font-face{font-family:Manrope;src:url('/assets/fonts/manrope-latin-600-normal.woff2') format('woff2');font-display:swap;font-weight:600}
@font-face{font-family:Manrope;src:url('/assets/fonts/manrope-latin-700-normal.woff2') format('woff2');font-display:swap;font-weight:700}
@font-face{font-family:Manrope;src:url('/assets/fonts/manrope-latin-800-normal.woff2') format('woff2');font-display:swap;font-weight:800}
@font-face{font-family:'IBM Plex Mono';src:url('/assets/fonts/ibm-plex-mono-latin-500-normal.woff2') format('woff2');font-display:swap;font-weight:500}

:root{color:#f7fbff;background:#031326;font-family:Manrope,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;font-synthesis:none;text-rendering:optimizeLegibility;--night:#031326;--night-deep:#020d1b;--night-soft:#081d33;--ink:#071b3d;--paper:#f8fbfd;--white:#f7fbff;--ice:#d9ecf7;--muted-dark:#9eb8cc;--muted-light:#53697f;--cyan:#25d3f2;--cyan-soft:#8ce7f5;--blue:#1769ff;--amber:#ffb21a;--error:#ff746d;--line-dark:#23516e;--line-bright:#68c9e3;--line-light:#bfd3df}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;min-width:320px;min-height:100vh;overflow-x:hidden;background-color:var(--night);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='48' height='48' viewBox='0 0 48 48'%3E%3Cpath d='M48 0H0V48' fill='none' stroke='%2312334d' stroke-width='1' stroke-opacity='.48'/%3E%3C/svg%3E")}
button,input{font:inherit}
button,a,input,summary{-webkit-tap-highlight-color:transparent}
a{color:inherit;text-underline-offset:.2em;text-decoration-thickness:1.5px}
:focus-visible{outline:3px solid rgba(37,211,242,.62);outline-offset:3px}
.skip-link{position:fixed;z-index:30;top:-100px;left:12px;padding:10px 14px;border:1px solid var(--cyan);background:var(--night-deep);color:var(--white);font-size:14px;font-weight:700;text-decoration:none}
.skip-link:focus{top:12px}
.app-shell{width:min(calc(100% - 72px),1400px);margin:0 auto}

.site-header{position:relative;min-height:72px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line-bright)}
.wordmark{color:var(--white);font-size:27px;font-weight:800;letter-spacing:-.052em;line-height:1;text-decoration:none}
.wordmark span{color:var(--cyan)}
.site-nav{display:flex;align-items:stretch;align-self:stretch;gap:42px}
.site-nav a{position:relative;display:flex;align-items:center;color:var(--white);font-size:15px;font-weight:700;text-decoration:none;transition:color 180ms ease}
.site-nav a::after{position:absolute;right:0;bottom:6px;left:0;height:3px;transform:scaleX(0);transform-origin:left;background:var(--cyan);content:'';transition:transform 180ms ease}
.site-nav a:hover,.site-nav a.is-current{color:var(--cyan)}
.site-nav a:hover::after,.site-nav a.is-current::after{transform:scaleX(1)}
.menu-button{display:none;width:48px;height:48px;padding:11px;border:0;background:transparent;color:var(--white);cursor:pointer}
.menu-button span{display:block;height:2px;margin:5px 0;background:currentColor;transition:transform 180ms ease,opacity 180ms ease}

.intro{padding:34px 0 26px}
.intro h1{max-width:1200px;margin:0;color:var(--white);font-size:clamp(48px,5.2vw,76px);font-weight:800;letter-spacing:-.06em;line-height:.98;text-wrap:balance}
.intro-copy{max-width:1060px;margin:14px 0 0;color:var(--ice);font-size:clamp(18px,1.75vw,24px);line-height:1.4;letter-spacing:-.022em;text-wrap:pretty}
.definition{margin:7px 0 0;color:var(--ice);font-size:17px;line-height:1.5}
.definition strong{color:var(--white);font-weight:800}

.calculator-layout{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.26fr);gap:clamp(32px,4vw,58px);padding:0 0 34px}
.calculator-form{min-width:0;padding-right:clamp(28px,3.4vw,50px);border-right:1px solid var(--line-bright)}
.calculator-form h2,.result-column>h2,.safety-section h2{margin:0 0 22px;color:var(--white);font-size:clamp(26px,2.2vw,34px);font-weight:800;letter-spacing:-.045em;line-height:1.08}
.segmented-fieldset,.driving-state{min-width:0;margin:0 0 16px;padding:0;border:0}
.segmented-fieldset{position:relative;display:block;padding-left:calc(36% + 16px)}
.segmented-fieldset legend{position:absolute;top:50%;left:0;width:36%;transform:translateY(-50%)}
.segmented-fieldset legend,.driving-state legend,.number-field>label{padding:0;color:#d9eaf4;font-family:'IBM Plex Mono',ui-monospace,SFMono-Regular,Consolas,monospace;font-size:12px;font-weight:500;letter-spacing:.095em;line-height:1.35;text-transform:uppercase}
.segmented-control{display:grid;grid-auto-flow:column;grid-auto-columns:1fr;min-width:0;overflow:hidden;border:1px solid #76b9d6;border-radius:8px;background:rgba(4,24,43,.78)}
.segment{min-height:45px;padding:0 16px;border:0;border-right:1px solid #3f6f8b;background:transparent;color:var(--white);font-size:15px;font-weight:700;cursor:pointer;transition:background-color 180ms ease,color 180ms ease,transform 120ms ease}
.segment:last-child{border-right:0}
.segment:hover{background:rgba(37,211,242,.09)}
.segment:active{transform:translateY(1px)}
.segment.is-selected{background:var(--cyan);color:#001524}
.number-field{display:grid;grid-template-columns:minmax(145px,.72fr) minmax(190px,1.28fr);align-items:center;gap:6px 16px;margin:0 0 15px}
.input-shell{position:relative;display:grid;grid-template-columns:1fr auto;min-width:0;overflow:hidden;border:1px solid #76b9d6;border-radius:8px;background:rgba(7,31,54,.88);transition:border-color 180ms ease,box-shadow 180ms ease,background-color 180ms ease}
.input-shell:focus-within{border-color:var(--cyan);box-shadow:0 0 0 2px rgba(37,211,242,.22);background:rgba(9,37,64,.96)}
.input-shell input{width:100%;min-width:0;height:47px;padding:0 16px;border:0;outline:0;background:transparent;color:var(--white);font-size:20px;font-weight:700;font-variant-numeric:tabular-nums}
.input-shell>span{min-width:62px;display:grid;place-items:center;border-left:1px solid #3f6f8b;color:var(--white);font-size:14px;font-weight:700}
.field-help,.field-error{grid-column:2;margin:0;font-size:11px;line-height:1.4}
.field-help{color:var(--muted-dark)}
.field-error{color:var(--error);font-weight:700}
.input-shell.has-error{border-color:var(--error);box-shadow:0 0 0 2px rgba(255,116,109,.18)}
.driving-state{display:grid;grid-template-columns:minmax(145px,.72fr) minmax(0,.64fr) minmax(0,.64fr);align-items:stretch;gap:8px 12px}
.driving-state legend{grid-row:1;grid-column:1;align-self:center}
.state-choice{position:relative;min-height:52px;display:flex;align-items:center;gap:10px;padding:8px 12px;border:1px solid #76b9d6;border-radius:8px;color:var(--white);cursor:pointer;transition:border-color 180ms ease,background-color 180ms ease}
.state-choice:hover{background:rgba(37,211,242,.07)}
.state-choice.is-selected{border-color:var(--cyan);box-shadow:inset 0 0 0 1px var(--cyan);background:rgba(37,211,242,.05)}
.state-choice input{width:18px;height:18px;flex:0 0 auto;margin:0;accent-color:var(--cyan)}
.state-choice span{font-size:13px;font-weight:700;line-height:1.2}
.driving-state>p{grid-column:2/4;margin:0;color:var(--muted-dark);font-size:11px;line-height:1.4}
.form-actions{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:20px;margin-top:24px}
.primary-button,.text-button{min-height:54px;border:0;border-radius:8px;font-size:15px;font-weight:800;cursor:pointer;transition:transform 140ms ease,background-color 180ms ease,color 180ms ease}
.primary-button{padding:0 24px;background:var(--cyan);color:#001524}
.primary-button:hover{background:#6be7f8}
.primary-button:active,.text-button:active{transform:translateY(1px) scale(.99)}
.text-button{padding:0 6px;background:transparent;color:var(--cyan)}
.text-button:hover{color:var(--white)}

.result-column{min-width:0}
.result-frame{min-width:0;animation:result-in 240ms ease-out}
.result-summary{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:28px;padding:2px 0 18px;border-bottom:1px solid var(--line-bright)}
.result-number,.result-change{margin:0;font-variant-numeric:tabular-nums}
.result-number{color:var(--white);font-size:clamp(54px,5.5vw,82px);font-weight:800;letter-spacing:-.065em;line-height:.95;white-space:nowrap}
.result-number #result-unit{letter-spacing:-.045em}
.result-change{padding-left:28px;border-left:1px solid var(--line-bright);color:var(--amber);font-size:clamp(20px,2.2vw,30px);font-weight:800;line-height:1.1;white-space:nowrap}
.pressure-path{margin:0;padding:8px 0 2px}
.pressure-path svg{width:100%;height:auto;display:block;overflow:visible}
.chart-grid line{stroke:#24506d;stroke-width:1}
.chart-line{stroke:var(--cyan);stroke-width:4;stroke-linecap:round}
.chart-point{fill:var(--cyan);stroke:var(--white);stroke-width:3}
.chart-label rect{fill:var(--night-soft);stroke:var(--cyan-soft);stroke-width:1}
.chart-label text{fill:var(--white);font-family:'IBM Plex Mono',ui-monospace,monospace;font-size:14px;font-weight:500}
.axis-label{fill:var(--muted-dark);font-family:'IBM Plex Mono',ui-monospace,monospace;font-size:12px;letter-spacing:.08em}
.next-action{padding-top:4px}
.next-action h3{margin:0 0 8px;color:var(--white);font-size:clamp(24px,2.1vw,32px);font-weight:800;letter-spacing:-.045em;line-height:1.08}
.action-copy{margin:0;padding:0 0 0 18px;border-left:6px solid var(--amber);color:var(--amber);font-size:clamp(17px,1.45vw,22px);font-weight:700;line-height:1.32;text-wrap:pretty}
.estimate-limit{margin:12px 0 0;padding-top:11px;border-top:1px solid var(--line-bright);color:var(--white);font-size:15px;font-weight:800}
.service-note{margin:4px 0 0;color:var(--muted-dark);font-size:12px;line-height:1.45}

.safety-section{padding:27px 0 36px;border-top:1px solid var(--line-bright)}
.safety-steps{position:relative;display:grid;grid-template-columns:repeat(3,1fr);gap:34px;margin:0;padding:0;list-style:none}
.safety-steps::before{position:absolute;top:17px;right:2%;left:2%;height:2px;background:var(--cyan);content:''}
.safety-steps li{position:relative;min-width:0;display:grid;grid-template-columns:38px 1fr;gap:10px}
.safety-steps li>span{position:relative;z-index:1;width:36px;height:36px;display:grid;place-items:center;border-radius:50%;background:var(--cyan);color:#001524;font-size:15px;font-weight:800}
.safety-steps li>div{padding-top:44px;margin-left:-48px}
.safety-steps h3{margin:0;color:var(--white);font-size:18px;font-weight:800;letter-spacing:-.025em}
.safety-steps p{max-width:42ch;margin:5px 0 0;color:var(--ice);font-size:13px;line-height:1.45}

.method-sources-row,.faq-section,footer{position:relative;color:var(--ink);background:var(--paper);box-shadow:0 0 0 100vmax var(--paper);clip-path:inset(0 -100vmax)}
.method-sources-row{display:grid;grid-template-columns:1fr 1fr;gap:0;padding:56px 0 46px;border-top:1px solid var(--line-light)}
.method-section{padding-right:48px}
.sources-section{padding-left:48px;border-left:1px solid var(--line-light)}
.method-section h2,.sources-section h2,.faq-section h2{margin:0;color:var(--ink);font-size:clamp(34px,3.2vw,48px);font-weight:800;letter-spacing:-.055em;line-height:1}
.method-section>p,.sources-section>p{color:var(--muted-light);font-size:14px;line-height:1.55}
.method-section>p:first-of-type{max-width:62ch;margin:12px 0 0}
.formula{display:block;margin:18px 0 15px;padding:17px 20px;border-left:4px solid var(--blue);background:#edf4f8;color:var(--ink)!important;font-size:clamp(17px,1.55vw,22px)!important;font-weight:800;text-align:center;font-variant-numeric:tabular-nums}
.sources-section ul{margin:15px 0 0;padding:0;list-style:none}
.sources-section li{display:grid;grid-template-columns:170px 1fr;gap:16px;padding:10px 0;border-bottom:1px solid #d8e4eb;font-size:14px;line-height:1.4}
.sources-section li:last-child{border-bottom:0}
.sources-section li a{color:#0056d8;font-weight:800}
.sources-section li a:hover{color:#003d9c}
.sources-section li span{color:var(--muted-light)}
.source-date{margin-bottom:0;font-size:12px!important}
.faq-section{padding:34px 0 58px;border-top:1px solid var(--line-light)}
.faq-section h2{margin-bottom:8px}
.faq-section details{border-bottom:1px solid var(--line-light)}
.faq-section summary{position:relative;padding:19px 52px 19px 0;color:var(--ink);font-size:17px;font-weight:800;cursor:pointer;list-style:none}
.faq-section summary::-webkit-details-marker{display:none}
.faq-section summary::before,.faq-section summary::after{position:absolute;top:50%;right:9px;width:15px;height:2px;transform:translateY(-50%);background:var(--ink);content:'';transition:transform 160ms ease}
.faq-section summary::after{transform:translateY(-50%) rotate(90deg)}
.faq-section details[open] summary::after{transform:translateY(-50%) rotate(0)}
.faq-section details p{max-width:74ch;margin:-2px 0 18px;color:var(--muted-light);font-size:15px;line-height:1.6}
footer{display:flex;justify-content:space-between;gap:30px;padding:24px 0 34px;border-top:1px solid var(--line-light);color:var(--muted-light);font-size:12px;line-height:1.5}
footer p{margin:0}
footer strong{color:var(--ink)}
.noscript-message{width:min(calc(100% - 40px),1120px);margin:24px auto;padding:13px 16px;border:1px solid var(--line-bright);background:var(--night-deep);color:var(--ice);font-size:14px}

@keyframes result-in{from{opacity:.7;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}

@media(max-width:1120px){
  .app-shell{width:min(calc(100% - 48px),1040px)}
  .calculator-layout{grid-template-columns:minmax(0,.94fr) minmax(0,1.06fr);gap:32px}
  .segmented-fieldset{padding-left:0}
  .segmented-fieldset legend{position:static;width:auto;margin-bottom:7px;transform:none}
  .number-field{grid-template-columns:1fr;gap:7px}
  .field-help,.field-error{grid-column:1}
  .driving-state{grid-template-columns:1fr 1fr}
  .driving-state legend,.driving-state>p{grid-column:1/3}
  .result-change{padding-left:18px}
}

@media(max-width:900px){
  .calculator-layout{grid-template-columns:1fr;gap:34px}
  .calculator-form{padding-right:0;padding-bottom:36px;border-right:0;border-bottom:1px solid var(--line-bright)}
  .number-field{grid-template-columns:minmax(160px,.72fr) minmax(240px,1.28fr)}
  .field-help,.field-error{grid-column:2}
  .driving-state{grid-template-columns:minmax(160px,.72fr) minmax(0,.64fr) minmax(0,.64fr)}
  .driving-state legend{grid-column:1}
  .driving-state>p{grid-column:2/4}
}

@media(max-width:700px){
  .app-shell{width:min(calc(100% - 32px),560px)}
  .site-header{min-height:64px}
  .wordmark{font-size:24px}
  .menu-button{display:block}
  .site-nav{position:absolute;z-index:10;top:63px;right:0;left:0;display:none;height:auto;align-items:stretch;gap:0;border:1px solid var(--line-bright);background:#04162a}
  .site-nav.is-open{display:grid}
  .site-nav a{min-height:52px;padding:0 16px;border-bottom:1px solid var(--line-dark)}
  .site-nav a:last-child{border-bottom:0}
  .site-nav a::after{display:none}
  .intro{padding:28px 0 24px}
  .intro h1{max-width:9ch;font-size:clamp(42px,12.8vw,52px);line-height:.96}
  .intro-copy{margin-top:14px;font-size:17px;line-height:1.42}
  .definition{margin-top:9px;font-size:14px}
  .calculator-layout{gap:28px;padding-bottom:28px}
  .calculator-form{padding-bottom:30px}
  .calculator-form h2,.result-column>h2,.safety-section h2{margin-bottom:20px;font-size:28px}
  .number-field{grid-template-columns:1fr;gap:7px}
  .segmented-fieldset{margin-bottom:18px}
  .field-help,.field-error{grid-column:1}
  .segment{min-height:47px;font-size:14px}
  .input-shell input{height:49px;font-size:18px}
  .driving-state{grid-template-columns:1fr 1fr;margin-top:3px}
  .driving-state legend,.driving-state>p{grid-column:1/3}
  .state-choice{min-height:52px}
  .state-choice span{font-size:12px}
  .form-actions{grid-template-columns:1fr;gap:4px;margin-top:22px}
  .primary-button,.text-button{min-height:54px}
  .result-summary{grid-template-columns:1fr;gap:8px;padding-bottom:14px}
  .result-number{font-size:clamp(47px,14vw,58px)}
  .result-change{padding-left:0;border-left:0;font-size:20px}
  .pressure-path{padding:6px 0 0}
  .chart-label text{font-size:16px}
  .axis-label{font-size:14px}
  .next-action h3{font-size:26px}
  .action-copy{padding-left:14px;border-left-width:5px;font-size:16px}
  .safety-section{padding:30px 0 40px}
  .safety-steps{grid-template-columns:1fr;gap:0;padding-left:0}
  .safety-steps::before{top:18px;bottom:20px;left:17px;width:2px;height:auto}
  .safety-steps li{grid-template-columns:36px 1fr;gap:12px;padding-bottom:28px}
  .safety-steps li:last-child{padding-bottom:0}
  .safety-steps li>span{width:36px;height:36px}
  .safety-steps li>div{padding-top:3px;margin-left:0}
  .safety-steps h3{font-size:17px}
  .method-sources-row{grid-template-columns:1fr;padding:44px 0 36px}
  .method-section,.sources-section{padding:0}
  .sources-section{margin-top:38px;padding-top:38px;border-top:1px solid var(--line-light);border-left:0}
  .method-section h2,.sources-section h2,.faq-section h2{font-size:38px}
  .formula{padding:16px 14px;font-size:17px!important;line-height:1.5}
  .sources-section li{grid-template-columns:1fr;gap:3px;padding:9px 0}
  .faq-section{padding:32px 0 48px}
  .faq-section summary{padding:18px 45px 18px 0;font-size:16px;line-height:1.25}
  .faq-section details p{margin-top:0;font-size:14px}
  footer{display:grid;gap:10px;padding:23px 0 30px}
}

@media(max-width:390px){
  .app-shell{width:calc(100% - 28px)}
  .intro h1{font-size:43px}
  .calculator-form h2,.result-column>h2,.safety-section h2{font-size:26px}
  .state-choice{padding-inline:9px}
  .state-choice span{font-size:11.5px}
  .result-number{font-size:46px}
}

@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
}