:root{--blue:#2438E8;--deep:#0F1C8C;--pink:#FF8FB1;--lemon:#F4F26B;--mist:#EEF1FF;--ink:#0C1250;
  --head:"Unbounded","Arial Black",system-ui,sans-serif;--body:"Instrument Sans",system-ui,-apple-system,"Segoe UI",sans-serif}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
body{margin:0;font-family:var(--body);font-size:1.08rem;line-height:1.6;color:var(--ink);background:var(--mist)}
a{color:inherit}
:focus-visible{outline:3px solid var(--lemon);outline-offset:3px}
.sec :focus-visible{outline-color:var(--blue)}

.top{position:absolute;inset:0 0 auto 0;z-index:5;display:flex;justify-content:space-between;align-items:center;padding:22px clamp(20px,5vw,72px) 22px;color:#fff}
.brand{font:800 1.7rem var(--head);text-decoration:none;letter-spacing:-.04em}
nav{display:flex;gap:24px}
nav a{text-decoration:none;font-weight:600}
nav a:hover{text-decoration:underline;text-underline-offset:5px}

.tank{position:relative;min-height:100vh;background:linear-gradient(180deg,var(--blue) 0%,var(--deep) 100%);color:#fff;display:flex;align-items:flex-end;overflow:hidden}
#bubbles{position:absolute;inset:0;width:100%;height:100%;cursor:crosshair}
.tank-text{position:relative;z-index:2;padding:0 clamp(20px,5vw,72px) 64px;max-width:760px;pointer-events:none}
.tank-text .dial{pointer-events:auto}
h1{font:800 clamp(2.1rem,5.2vw,4.2rem)/1.04 var(--head);letter-spacing:-.04em;margin:0 0 22px}
.lead{max-width:48ch;font-size:1.2rem;margin:0 0 30px}
.dial{background:rgba(15,28,140,.65);backdrop-filter:blur(6px);border:2px solid var(--pink);border-radius:20px;padding:18px 22px;max-width:440px}
.dial label{font-weight:600;display:block;margin-bottom:8px}
.dial output{font:800 1.3rem var(--head);color:var(--lemon)}
.dial small{display:block;margin-top:8px;opacity:.85}
input[type=range]{width:100%;accent-color:var(--pink)}

.sec{padding:96px clamp(20px,5vw,72px);max-width:1040px;margin:0 auto}
.sec.alt{max-width:none;background:var(--lemon)}
.sec.alt>*{max-width:900px;margin-left:auto;margin-right:auto}
h2{font:800 clamp(1.7rem,3.6vw,2.6rem)/1.1 var(--head);letter-spacing:-.04em;margin:0 0 12px;max-width:20ch}
.sub{margin:0 0 36px;opacity:.8}

.models{list-style:none;padding:0;margin:0;display:grid;gap:34px}
.models li{display:grid;grid-template-columns:1fr auto;gap:6px 24px;align-items:end}
.models h3{font:800 1.3rem var(--head);margin:0;letter-spacing:-.03em}
.models p{margin:0;grid-column:1/2}
.models .spec{grid-column:2/3;grid-row:1/3;text-align:right;font-weight:600;font-size:.95rem}
.bar{grid-column:1/-1;height:26px;border-radius:99px;background:rgba(36,56,232,.12);overflow:hidden}
.bar i{display:block;height:100%;width:var(--w);border-radius:99px;background:var(--blue);background-image:radial-gradient(circle at 14px 50%,var(--pink) 5px,transparent 6px);background-size:34px 100%}

.lit{display:grid;gap:12px;max-width:560px}
.lit label{font-weight:600}
input,textarea{font:inherit;color:var(--ink);background:#fff;border:2px solid var(--ink);border-radius:14px;padding:12px 16px;width:100%}
.rec{margin-top:12px;background:var(--ink);color:#fff;border-radius:20px;padding:22px}
.rec strong{display:block;font:800 1.3rem var(--head);letter-spacing:-.03em;color:var(--lemon);margin-bottom:6px}

form{display:grid;grid-template-columns:1fr 1fr;gap:18px;max-width:720px}
.field{display:flex;flex-direction:column;gap:6px}
.field.wide,form .btn,.ok{grid-column:1/-1}
.field label{font-weight:600}
.err{color:#B3123B;font-weight:600;min-height:1.1em}
.field.bad input,.field.bad textarea{border-color:#B3123B}
.btn{justify-self:start;background:var(--blue);color:#fff;border:0;border-radius:99px;padding:15px 32px;font:600 1rem var(--body);cursor:pointer;transition:transform .15s,background .15s}
.btn:hover{background:var(--deep);transform:translateY(-2px)}
.ok{font-weight:600;color:var(--blue);margin:0}

footer{display:flex;flex-wrap:wrap;gap:10px 32px;padding:34px clamp(20px,5vw,72px);background:var(--ink);color:#fff;font-size:.95rem}

.gauge{position:fixed;right:14px;top:90px;bottom:40px;width:46px;z-index:6;pointer-events:none}
.gauge-track{position:relative;height:100%;width:6px;margin-left:auto;border-radius:3px;background:repeating-linear-gradient(180deg,rgba(255,255,255,.9) 0 2px,transparent 2px 22px);mix-blend-mode:difference}
.gauge-mark{position:absolute;right:12px;top:0;transform:translateY(-50%);background:var(--pink);color:var(--ink);font-size:.75rem;padding:3px 9px;border-radius:99px;white-space:nowrap;font-weight:600}
@media (max-width:720px){
  .gauge{display:none}
  nav a:nth-child(2){display:none}
  .models li{grid-template-columns:1fr}
  .models .spec{grid-column:1;grid-row:auto;text-align:left}
  form{grid-template-columns:1fr}
}