:root{
  color-scheme: light;
  --ink:#0E3A53;        /* deep pool-tile blue */
  --ink-soft:#4A6272;
  --water:#22B8CC;      /* pool water */
  --water-deep:#1690A3;
  --mist:#EAF6F8;       /* sky over the water */
  --coping:#E4E8E6;     /* concrete pool edge */
  --float:#FF7A59;      /* pool-float coral, used for alerts only */
  --grass:#6DB57D;
  --paper:#FFFFFF;
  --tint:#DDF2F5;       /* shallow-end water tint */
  --line:#CFDDE2;
  --display:"Bricolage Grotesque", "Avenir Next", "Segoe UI", system-ui, sans-serif;
  --body:"Atkinson Hyperlegible", "Segoe UI", system-ui, -apple-system, sans-serif;
  --measure:62ch;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    color-scheme: dark;
    --ink:#E3F3F7; --ink-soft:#A9C2CC; --water:#2BC3D6; --water-deep:#5AD3E2;
    --mist:#0F2A38; --tint:#0D3343; --coping:#16384A; --paper:#0A1F2B; --line:#24485A; --grass:#4E9A61;
  }
}
:root[data-theme="dark"]{
  color-scheme: dark;
  --ink:#E3F3F7; --ink-soft:#A9C2CC; --water:#2BC3D6; --water-deep:#5AD3E2;
  --mist:#0F2A38; --tint:#0D3343; --coping:#16384A; --paper:#0A1F2B; --line:#24485A; --grass:#4E9A61;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--paper);color:var(--ink);font:400 1.0625rem/1.6 var(--body);-webkit-font-smoothing:antialiased}
img,svg{max-width:100%;display:block}
a{color:inherit}
:focus-visible{outline:3px solid var(--float);outline-offset:3px;border-radius:4px}
.wrap{width:min(1120px,100% - 2.5rem);margin-inline:auto}
h1,h2,h3{font-family:var(--display);line-height:1.08;margin:0;letter-spacing:-.015em}
h2{font-size:clamp(1.9rem,1.3rem + 2.2vw,2.9rem);font-weight:800;max-width:22ch}
h3{font-size:1.25rem;font-weight:700}
p{margin:0;max-width:var(--measure)}
.lead{font-size:1.2rem;color:var(--ink-soft)}
section{padding-block:clamp(4rem,8vw,7rem)}
.stack>*+*{margin-top:1rem}

/* ---------- nav ---------- */
.nav{position:absolute;inset:0 0 auto;z-index:3;padding-top:env(safe-area-inset-top,0px)}
.nav .wrap{display:flex;align-items:center;justify-content:space-between;padding-block:1.25rem}
.brand{font:800 1.35rem/1 var(--display);text-decoration:none;letter-spacing:-.02em}
.brand span{color:var(--water-deep)}
.nav a.btn{padding:.6rem 1.1rem;font-size:.95rem}

/* ---------- buttons ---------- */
.btn{display:inline-block;font:700 1rem/1 var(--body);text-decoration:none;padding:.95rem 1.4rem;border-radius:999px;background:var(--ink);color:var(--paper);border:2px solid var(--ink);cursor:pointer}
.btn:hover{background:transparent;color:var(--ink)}
.btn.ghost{background:transparent;color:var(--ink)}
.btn.ghost:hover{background:var(--ink);color:var(--paper)}

/* ---------- hero: the page itself is a pool, filling to its target line ---------- */
.hero{position:relative;min-height:min(92vh,820px);background:var(--mist);overflow:hidden;display:flex;align-items:center;padding-block:7rem 0}
.hero .copy{position:relative;z-index:2;padding-bottom:18.5rem}
.hero h1{font-size:clamp(2.8rem,1.6rem + 5.6vw,6.2rem);font-weight:800;max-width:11ch;letter-spacing:-.035em}
.hero .lead{margin-top:1.4rem;max-width:44ch;color:var(--ink-soft)}
.hero .actions{display:flex;flex-wrap:wrap;gap:.75rem;margin-top:2rem}
.pool{position:absolute;inset:auto 0 0 0;height:15rem;z-index:1}
.pool .level{position:absolute;inset:0;transform:translateY(5.5rem);animation:fill 3.2s cubic-bezier(.3,.7,.2,1) .4s forwards}
.pool .level svg{position:absolute;top:-28px;left:0;width:200%;max-width:none;height:30px;animation:drift 9s linear infinite}
.pool .level .body{position:absolute;inset:0;background:linear-gradient(var(--water),var(--water-deep))}
.target{position:absolute;left:0;right:0;top:0;z-index:2;border-top:2px dashed var(--ink);opacity:.55}
.target span{position:absolute;right:1.25rem;top:-1.9rem;font-size:.9rem;font-weight:700;background:var(--mist);padding:0 .4rem}
@keyframes fill{to{transform:translateY(0)}}
@keyframes drift{to{transform:translateX(-50%)}}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .pool .level{animation:none;transform:none}
  .pool .level svg{animation:none}
}

/* ---------- problem ---------- */
.problem .grid{display:grid;grid-template-columns:1fr 1fr;gap:clamp(2rem,6vw,6rem);align-items:start}
.problem .facts{display:grid;gap:1.75rem}
.problem .facts p{padding-left:1.1rem;border-left:4px solid var(--water)}
.problem .facts strong{display:block;font:700 1.15rem/1.3 var(--display);margin-bottom:.25rem}

/* ---------- system illustration ---------- */
.system{background:var(--mist)}
.system .intro{display:grid;gap:1rem;margin-bottom:2.5rem}
.figure{background:var(--paper);border-radius:28px;padding:clamp(.75rem,2vw,1.5rem);overflow-x:auto}
.figure svg{min-width:640px;width:100%;height:auto}
.figure svg text{font-family:var(--body)}
.steps{list-style:none;padding:0;margin:2.5rem 0 0;display:grid;grid-template-columns:repeat(4,1fr);gap:1.5rem;counter-reset:s}
.steps li{counter-increment:s;position:relative;padding-top:3rem}
.steps li::before{content:counter(s);position:absolute;top:0;left:0;width:2.2rem;height:2.2rem;border-radius:50%;background:var(--float);color:#fff;font:800 1.05rem/2.2rem var(--display);text-align:center}
.steps h3{margin-bottom:.35rem}
.steps p{color:var(--ink-soft);font-size:1rem}

/* ---------- in the box ---------- */
.box .grid{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem;margin-top:2.5rem}
.device{display:grid;grid-template-columns:120px 1fr;gap:1.5rem;align-items:center;padding:2rem;border:2px solid var(--line);border-radius:24px}
.device ul{margin:.6rem 0 0;padding-left:1.1rem;color:var(--ink-soft)}
.device li+li{margin-top:.3rem}

/* ---------- leaks ---------- */
.leaks{background:var(--tint);color:var(--ink)}
.leaks .chart{margin-top:2.5rem;background:var(--paper);border-radius:24px;padding:1.5rem;overflow-x:auto}
.leaks .chart svg{min-width:560px;width:100%;height:auto}
.leaks .chart svg text{font-family:var(--body)}
.compare{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem;margin-top:2rem}
.lane{border-radius:24px;padding:1.75rem;background:var(--paper)}
.lane.with{background:var(--paper);box-shadow:inset 0 0 0 2px var(--water)}
.lane ol{list-style:none;margin:1.2rem 0 0;padding:0;border-left:3px solid var(--line)}
.lane.with ol{border-left-color:var(--water)}
.lane li{position:relative;padding:0 0 1.1rem 1.4rem}
.lane li:last-child{padding-bottom:0}
.lane li::before{content:"";position:absolute;left:-9px;top:.35rem;width:15px;height:15px;border-radius:50%;background:var(--ink-soft)}
.lane.with li::before{background:var(--water)}
.lane li.end::before{background:var(--float)}
.lane b{display:block}
.leaks .note{margin-top:1.25rem;font-size:.9rem;font-style:italic;color:var(--ink-soft)}

/* ---------- pricing ---------- */
.pricing .grid{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem;margin-top:2.5rem}
.plan{border:2px solid var(--line);border-radius:28px;padding:2.25rem}
.plan.plus{border-color:var(--water);background:var(--mist)}
.price{font:800 clamp(2.4rem,1.8rem + 2vw,3.4rem)/1 var(--display);margin:1rem 0 .25rem;letter-spacing:-.03em}
.price small{font:400 1rem var(--body);color:var(--ink-soft);letter-spacing:0}
.plan ul{margin:1.25rem 0 0;padding-left:1.1rem}
.plan li+li{margin-top:.4rem}
.offer{margin-top:1.5rem;padding:1.25rem 1.5rem;border-radius:20px;background:var(--water);color:#06303D;font-weight:700}

/* ---------- pilot form ---------- */
.pilot{background:var(--mist)}
.pilot .grid{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:clamp(2rem,5vw,5rem);align-items:start}
form{background:var(--paper);border-radius:28px;padding:clamp(1.5rem,3vw,2.5rem);display:grid;gap:1.5rem}
fieldset{border:0;margin:0;padding:0;display:grid;gap:.5rem}
legend{font-weight:700;margin-bottom:.4rem;padding:0}
.choices{display:flex;flex-wrap:wrap;gap:.5rem}
.choices label{position:relative}
.choices input{position:absolute;opacity:0;inset:0;margin:0;cursor:pointer}
.choices span{display:inline-block;padding:.55rem 1rem;border:2px solid var(--line);border-radius:999px;font-size:.95rem;cursor:pointer}
.choices input:checked+span{background:var(--ink);border-color:var(--ink);color:var(--paper)}
.choices input:focus-visible+span{outline:3px solid var(--float);outline-offset:2px}
.field{display:grid;gap:.35rem}
.field label{font-weight:700}
.field input,.field textarea{font:inherit;color:var(--ink);background:var(--paper);border:2px solid var(--line);border-radius:14px;padding:.75rem .9rem;width:100%}
.field input:focus,.field textarea:focus{border-color:var(--water);outline:none}
.row{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
.check{display:flex;gap:.6rem;align-items:flex-start;font-size:.95rem}
.check input{margin-top:.3rem;width:1.1rem;height:1.1rem;accent-color:var(--ink)}
.privacy{font-size:.9rem;color:var(--ink-soft)}
.hint{font-size:.9rem;color:var(--ink-soft)}
#why-no{display:none}
#why-no.show{display:grid}
.thanks{display:none;background:var(--paper);border-radius:28px;padding:2.5rem}
.thanks.show{display:block}

/* ---------- faq ---------- */
.faq .list{margin-top:2rem;border-top:2px solid var(--line);max-width:820px}
details{border-bottom:2px solid var(--line);padding:1.25rem 0}
summary{cursor:pointer;font:700 1.15rem/1.35 var(--display);list-style:none;display:flex;justify-content:space-between;gap:1rem}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";font-size:1.5rem;line-height:1;color:var(--water-deep)}
details[open] summary::after{content:"–"}
details p{margin-top:.75rem;color:var(--ink-soft)}

/* ---------- footer ---------- */
footer{padding-block:3rem calc(3rem + env(safe-area-inset-bottom,0px));border-top:2px solid var(--line)}
footer .wrap{display:flex;flex-wrap:wrap;justify-content:space-between;gap:1.5rem;align-items:end}
footer p{font-size:.95rem;color:var(--ink-soft)}
footer a{font-weight:700;text-decoration:none}
footer a:hover{text-decoration:underline}

@media (max-width:860px){
  .problem .grid,.box .grid,.compare,.pricing .grid,.pilot .grid{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr 1fr}
  .device{grid-template-columns:90px 1fr;padding:1.5rem}
}
@media (max-width:520px){
  .steps{grid-template-columns:1fr}
  .row{grid-template-columns:1fr}
  .hero .copy{padding-bottom:15.5rem}
  .pool{height:12rem}
  .nav a.btn{display:none}
}