/* PlantCalc — industrial design system
   Palette: paper #F4F5F3 / ink #1B2026 / steel #55606B / amber #E89B0C / HMI panel #171C21 */
:root{
  --paper:#F4F5F3; --ink:#1B2026; --steel:#55606B; --line:#D9DDDA;
  --amber:#E89B0C; --amber-deep:#C98407; --glow:#FFB627;
  --panel:#171C21; --panel-line:#2A323B; --green:#37A05C; --red:#E05252;
  --maxw:1060px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important;animation:none!important}}
body{background:var(--paper);color:var(--ink);font:16px/1.65 "Inter",system-ui,sans-serif}
.display{font-family:"Saira Condensed","Inter",sans-serif;text-transform:uppercase;letter-spacing:.04em}
.mono{font-family:"IBM Plex Mono",ui-monospace,monospace}
a{color:inherit}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* top hazard rule */
.hazard{height:6px;background:repeating-linear-gradient(135deg,var(--amber) 0 14px,var(--ink) 14px 28px)}

/* nav */
nav{border-bottom:1px solid var(--line);background:var(--paper)}
.navrow{display:flex;align-items:center;justify-content:space-between;height:60px}
.wordmark{font-family:"Saira Condensed",sans-serif;font-weight:700;font-size:22px;letter-spacing:.08em;text-transform:uppercase;text-decoration:none}
.wordmark span{color:var(--amber-deep)}
.navlinks{display:flex;gap:22px;font-size:14px}
.navlinks a{text-decoration:none;color:var(--steel)}
.navlinks a:hover,.navlinks a[aria-current]{color:var(--ink)}

/* headers */
.eyebrow{font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--steel);font-weight:600}
h1{font-family:"Saira Condensed",sans-serif;font-weight:700;text-transform:uppercase;letter-spacing:.02em;font-size:clamp(34px,5vw,52px);line-height:1.05;margin:10px 0 14px}
.lede{color:var(--steel);max-width:62ch;font-size:17px}
.pagehead{padding:44px 0 30px}

/* calculator card */
.calc{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--ink);background:#fff;margin:8px 0 40px}
.calc-in{padding:28px 26px;border-right:1px solid var(--line)}
.calc-in h2{font-size:13px;letter-spacing:.14em;text-transform:uppercase;color:var(--steel);margin-bottom:18px}
.field{margin-bottom:16px}
.field label{display:block;font-size:13px;font-weight:600;margin-bottom:5px}
.field small{display:block;color:var(--steel);font-size:12px;margin-top:3px}
.field input{width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:0;background:var(--paper);font:15px "IBM Plex Mono",monospace;color:var(--ink)}
.field input:focus{outline:2px solid var(--amber);outline-offset:1px;border-color:var(--amber)}

/* HMI readout — signature element */
.hmi{background:var(--panel);color:#B7C0C9;padding:28px 26px;display:flex;flex-direction:column;gap:18px}
.hmi h2{font-size:12px;letter-spacing:.18em;text-transform:uppercase;color:#6B7885;font-family:"Saira Condensed",sans-serif;font-weight:600;display:flex;align-items:center;gap:8px}
.hmi h2::before{content:"";width:8px;height:8px;background:var(--green);border-radius:50%;box-shadow:0 0 6px var(--green)}
.readout{border:1px solid var(--panel-line);padding:16px 18px;background:#10151A}
.readout .rlabel{font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:#6B7885}
.readout .rvalue{font-family:"IBM Plex Mono",monospace;font-size:clamp(30px,4vw,42px);font-weight:600;color:var(--glow);line-height:1.15;text-shadow:0 0 14px rgba(255,182,39,.25)}
.readout .rvalue .unit{font-size:.45em;color:#8A96A2;font-weight:400}
.subgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.subgrid .readout .rvalue{font-size:20px;text-shadow:none;color:#E8EDF2}
.bench{border:1px solid var(--panel-line);padding:14px 18px;background:#10151A}
.bench .track{position:relative;height:8px;background:#232B33;margin:12px 0 6px}
.bench .fill{position:absolute;left:0;top:0;bottom:0;background:linear-gradient(90deg,var(--amber-deep),var(--glow));max-width:100%}
.bench .tick{position:absolute;top:-4px;bottom:-4px;width:2px;background:#55636F}
.bench .scale{display:flex;justify-content:space-between;font-size:10px;color:#6B7885;font-family:"IBM Plex Mono",monospace}
.verdict{font-size:13px;color:#B7C0C9}
.verdict strong{color:#fff}

/* CTA */
.cta{background:var(--ink);color:#F4F5F3;margin:0 0 52px;border-left:6px solid var(--amber)}
.cta .inner{padding:26px;display:flex;gap:20px;align-items:center;justify-content:space-between;flex-wrap:wrap}
.cta h2{font-family:"Saira Condensed",sans-serif;text-transform:uppercase;font-size:22px;letter-spacing:.03em}
.cta p{color:#AEB7BF;font-size:14px;max-width:52ch;margin-top:4px}
.btn{display:inline-block;background:var(--amber);color:var(--ink);font-weight:700;text-decoration:none;padding:13px 22px;font-size:15px;white-space:nowrap}
.btn:hover{background:var(--glow)}
.btn:focus-visible{outline:3px solid #fff;outline-offset:2px}

/* content */
.content{max-width:72ch;padding-bottom:30px}
.content h2{font-family:"Saira Condensed",sans-serif;text-transform:uppercase;font-size:24px;letter-spacing:.03em;margin:34px 0 12px}
.content h3{font-size:17px;margin:22px 0 8px}
.content p{margin-bottom:14px;color:#333B42}
.content ul,.content ol{margin:0 0 14px 22px;color:#333B42}
.content li{margin-bottom:6px}
.formula{background:#fff;border:1px solid var(--line);border-left:4px solid var(--amber);padding:14px 18px;font-family:"IBM Plex Mono",monospace;font-size:14px;margin:16px 0;overflow-x:auto}
table{border-collapse:collapse;width:100%;margin:16px 0;font-size:14px;background:#fff}
th,td{border:1px solid var(--line);padding:9px 12px;text-align:left}
th{font-family:"Saira Condensed",sans-serif;text-transform:uppercase;letter-spacing:.06em;font-size:13px;background:var(--paper)}

/* index cards */
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:26px 0 50px}
.card{background:#fff;border:1px solid var(--ink);padding:24px;display:flex;flex-direction:column;text-decoration:none;transition:transform .12s ease,box-shadow .12s ease}
.card:hover{transform:translateY(-3px);box-shadow:4px 4px 0 var(--amber)}
.card:focus-visible{outline:3px solid var(--amber);outline-offset:2px}
.card .tag{font-family:"IBM Plex Mono",monospace;font-size:11px;color:var(--steel);letter-spacing:.1em}
.card h2{font-family:"Saira Condensed",sans-serif;text-transform:uppercase;font-size:24px;margin:8px 0 8px}
.card p{font-size:14px;color:var(--steel);flex:1}
.card .go{margin-top:16px;font-weight:700;font-size:14px;color:var(--amber-deep)}

/* footer */
footer{border-top:1px solid var(--line);margin-top:30px}
footer .inner{padding:26px 0;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;font-size:13px;color:var(--steel)}
footer a{color:var(--steel)}

@media (max-width:820px){
  .calc{grid-template-columns:1fr}
  .calc-in{border-right:0;border-bottom:1px solid var(--line)}
  .grid3{grid-template-columns:1fr}
  .subgrid{grid-template-columns:1fr 1fr 1fr}
  .navlinks{display:none}
}