/* ============================================================
   The Boil Test · visual system
   Ground:  kettle-interior mineral white (cool, never cream)
   Ink:     deep slate-green
   Accent:  limescale ochre (the residue itself)
   Data:    meter green, reserved strictly for live numbers
   ============================================================ */

:root{
  --ground:#EFF2F1;
  --ground-deep:#E4E9E7;
  --ink:#12201F;
  --slate:#5A6B69;
  --scale:#C9BFA6;
  --scale-deep:#A8996F;
  --lcd:#0F7A5F;
  --line:#D3D9D7;
  --white:#FBFCFC;

  --f-display:"Archivo",system-ui,sans-serif;
  --f-body:"Source Serif 4",Georgia,serif;
  --f-mono:"IBM Plex Mono",ui-monospace,monospace;

  --wrap:1140px;
  --gap:clamp(1.5rem,4vw,3rem);
}

*,*::before,*::after{box-sizing:border-box}

html{-webkit-text-size-adjust:100%}

body{
  margin:0;
  background:var(--ground);
  color:var(--ink);
  font-family:var(--f-body);
  font-size:clamp(1rem,.96rem + .2vw,1.125rem);
  line-height:1.62;
  font-optical-sizing:auto;
}

.wrap{width:min(100% - 2.5rem,var(--wrap));margin-inline:auto}

.sr-only{
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;
}

.skip{
  position:absolute;left:-9999px;top:0;background:var(--ink);color:var(--ground);
  padding:.7rem 1rem;z-index:99;
}
.skip:focus{left:.5rem;top:.5rem}

a{color:inherit}

:focus-visible{outline:2px solid var(--lcd);outline-offset:3px}

/* ── type roles ─────────────────────────────── */

h1,h2,h3{font-family:var(--f-display);font-weight:800;margin:0;line-height:1.04}

h1{
  font-size:clamp(2.1rem,1.2rem + 3.9vw,4.15rem);
  font-stretch:105%;
  letter-spacing:-.022em;
  text-wrap:balance;
}

.h-lead{
  font-size:clamp(1.65rem,1.1rem + 2.2vw,2.8rem);
  font-stretch:103%;
  letter-spacing:-.018em;
  margin-bottom:1.6rem;
  text-wrap:balance;
}

h3{font-size:1.06rem;font-stretch:88%;letter-spacing:.01em;text-transform:uppercase}

.eyebrow{
  font-family:var(--f-mono);
  font-size:.72rem;
  letter-spacing:.19em;
  text-transform:uppercase;
  color:var(--slate);
  margin:0 0 1rem;
}

.lede{font-size:clamp(1.08rem,1rem + .5vw,1.36rem);margin:1.5rem 0 0;max-width:34ch}
.lede-sub{color:var(--slate);margin:.7rem 0 0;max-width:34ch}

/* ── masthead ───────────────────────────────── */

.masthead{border-bottom:1px solid var(--line);background:var(--ground)}
.masthead-in{
  display:flex;align-items:baseline;justify-content:space-between;
  gap:1rem;padding:1.1rem 0;flex-wrap:wrap;
}
.wordmark{
  font-family:var(--f-display);font-weight:900;font-stretch:112%;
  font-size:1.12rem;letter-spacing:-.015em;text-transform:uppercase;
}
.masthead-note{
  font-family:var(--f-mono);font-size:.7rem;letter-spacing:.1em;
  text-transform:uppercase;color:var(--slate);
}

/* ── hero ───────────────────────────────────── */

.hero{padding:clamp(2.5rem,6vw,5rem) 0 clamp(2.5rem,5vw,4rem)}
.hero-grid{
  display:grid;gap:clamp(2rem,5vw,4rem);
  grid-template-columns:1fr;align-items:start;
}
@media (min-width:940px){
  .hero-grid{grid-template-columns:1.06fr .94fr}
}

/* ── SIGNATURE: reduction rig ───────────────── */

.rig{margin:0}

.rig-frame{
  display:grid;grid-template-columns:auto 1fr;gap:clamp(1.2rem,3vw,2.2rem);
  align-items:stretch;
  background:var(--white);
  border:1px solid var(--line);
  padding:clamp(1.1rem,3vw,1.7rem);
}

.vessel{
  position:relative;width:clamp(86px,17vw,116px);height:clamp(190px,30vw,248px);
  border:2px solid var(--ink);border-top:none;
  border-radius:0 0 9px 9px;
  background:linear-gradient(180deg,rgba(18,32,31,.03),rgba(18,32,31,.07));
  overflow:hidden;
}

.vessel-water{
  position:absolute;left:0;right:0;bottom:0;height:88%;
  background:linear-gradient(180deg,rgba(15,122,95,.20),rgba(15,122,95,.34));
  transition:height .28s linear;
}
.vessel-surface{
  position:absolute;left:0;right:0;top:0;height:2px;
  background:var(--lcd);opacity:.85;
}
.vessel-residue{
  position:absolute;left:0;right:0;bottom:0;height:0;
  background:
    repeating-linear-gradient(90deg,var(--scale) 0 3px,var(--scale-deep) 3px 5px);
  transition:height .28s linear;
}
.vessel-ticks{position:absolute;inset:0;pointer-events:none}
.vessel-ticks span{
  position:absolute;left:0;width:9px;height:1px;bottom:var(--at);
  background:var(--ink);opacity:.28;
}

.readout{margin:0;display:flex;flex-direction:column;justify-content:center;gap:.1rem}
.readout-row{
  display:flex;align-items:baseline;justify-content:space-between;
  gap:.8rem;padding:.62rem 0;border-bottom:1px solid var(--line);
}
.readout-row:last-child{border-bottom:none}
.readout dt{
  font-family:var(--f-mono);font-size:.68rem;letter-spacing:.13em;
  text-transform:uppercase;color:var(--slate);
}
.readout dd{margin:0;font-family:var(--f-mono);font-size:1.42rem;font-weight:500;
  letter-spacing:-.02em;font-variant-numeric:tabular-nums}
.readout .unit{font-size:.7rem;color:var(--slate);margin-left:.22rem;letter-spacing:.06em}
.readout-row.is-live dd{color:var(--lcd)}

.rig-controls{
  border:1px solid var(--line);border-top:none;background:var(--white);
  padding:clamp(1rem,2.4vw,1.4rem);
}
.rig-controls label{
  display:flex;justify-content:space-between;align-items:baseline;gap:.7rem;
  font-family:var(--f-mono);font-size:.7rem;letter-spacing:.13em;
  text-transform:uppercase;color:var(--ink);flex-wrap:wrap;
}
.rig-controls .hint{text-transform:none;letter-spacing:.02em;color:var(--slate);font-size:.72rem}

input[type=range]{
  width:100%;margin:.95rem 0 .2rem;accent-color:var(--lcd);
  height:1.4rem;background:transparent;
}

.rig-scale{
  display:flex;justify-content:space-between;
  font-family:var(--f-mono);font-size:.64rem;color:var(--slate);letter-spacing:.08em;
}

.btn-boil{
  margin-top:1rem;width:100%;
  font-family:var(--f-display);font-weight:800;font-stretch:88%;
  text-transform:uppercase;letter-spacing:.1em;font-size:.82rem;
  background:var(--ink);color:var(--ground);
  border:none;padding:.88rem 1rem;cursor:pointer;
  transition:background .16s ease;
}
.btn-boil:hover{background:var(--lcd)}
.btn-boil[disabled]{opacity:.45;cursor:default}

.rig figcaption{
  font-size:.86rem;color:var(--slate);margin-top:.95rem;max-width:46ch;line-height:1.5;
}

/* ── bands ──────────────────────────────────── */

.band{padding:clamp(2.8rem,6.5vw,5.2rem) 0;border-top:1px solid var(--line)}
.band-truth{background:var(--ground-deep)}
.band-table{background:var(--ground-deep)}

.cols{display:grid;gap:var(--gap);grid-template-columns:1fr}
@media (min-width:800px){.cols{grid-template-columns:1fr 1fr}}
.col p{margin:0 0 1.1rem}
.col p:last-child{margin-bottom:0}

.pull{
  border-left:3px solid var(--scale-deep);
  padding-left:1.1rem;font-size:1.1rem;
}

.note{
  margin:2.2rem 0 0;font-size:.94rem;color:var(--slate);
  border-top:1px solid var(--line);padding-top:1.1rem;max-width:72ch;
}

/* ── mechanism cards ────────────────────────── */

.mech{display:grid;gap:var(--gap);grid-template-columns:1fr}
@media (min-width:800px){.mech{grid-template-columns:1fr 1fr}}

.mech-card{
  background:var(--white);border:1px solid var(--line);
  padding:clamp(1.3rem,3vw,1.9rem);
}
.mech-card.is-yes{border-color:var(--lcd);border-width:2px}
.mech-card h3{margin-bottom:.7rem}
.mech-card p{margin:0 0 1rem;font-size:.98rem}
.mech-card p:last-child{margin-bottom:0}

.mech-verdict{
  font-family:var(--f-mono);font-size:.74rem;letter-spacing:.1em;
  text-transform:uppercase;
}
.mech-no{color:var(--scale-deep)}
.mech-yes{color:var(--lcd)}
.mech-foot{color:var(--slate);font-size:.9rem;border-top:1px solid var(--line);padding-top:.9rem}

/* ── table ──────────────────────────────────── */

.table-intro{max-width:64ch;color:var(--slate);margin:0 0 1.8rem}

.table-scroll{overflow-x:auto;border:1px solid var(--line);background:var(--white)}

.cmp{border-collapse:collapse;width:100%;min-width:640px;font-size:.95rem}
.cmp th,.cmp td{padding:.9rem 1.05rem;text-align:left;border-bottom:1px solid var(--line)}
.cmp thead th{
  font-family:var(--f-mono);font-size:.67rem;letter-spacing:.13em;text-transform:uppercase;
  color:var(--slate);font-weight:400;background:var(--ground);
}
.cmp tbody th{font-family:var(--f-display);font-weight:700;font-stretch:96%;font-size:1rem}
.cmp tbody tr:last-child th,.cmp tbody tr:last-child td{border-bottom:none}
.cmp tr.is-note{background:rgba(15,122,95,.055)}
/* raise specificity above `.cmp th, .cmp td` which sets text-align:left */
.cmp th.ta-r,.cmp td.ta-r{text-align:right}
.num-c{font-family:var(--f-mono);font-variant-numeric:tabular-nums;letter-spacing:-.02em}
.muted{color:var(--slate)}

.tag{
  display:inline-block;font-family:var(--f-mono);font-size:.68rem;letter-spacing:.06em;
  padding:.16rem .45rem;border:1px solid var(--scale-deep);color:var(--scale-deep);
}

/* ── disclosure ─────────────────────────────── */

.disclose{
  margin-top:1.6rem;border:2px solid var(--ink);background:var(--white);
  padding:clamp(1.1rem,2.6vw,1.5rem);
}
.disclose-h{
  font-family:var(--f-mono);font-size:.7rem;letter-spacing:.15em;text-transform:uppercase;
  margin:0 0 .8rem;color:var(--ink);
}
.disclose p{margin:0 0 .8rem;font-size:.95rem}
.disclose p:last-child{margin-bottom:0}

/* ── protocol ───────────────────────────────── */

.band-protocol{background:var(--ground-deep)}

.steps{
  list-style:none;counter-reset:s;padding:0;margin:0;
  display:grid;gap:1px;background:var(--line);border:1px solid var(--line);
}
@media (min-width:820px){.steps{grid-template-columns:1fr 1fr}}
.steps li{
  counter-increment:s;background:var(--white);
  padding:clamp(1.2rem,2.8vw,1.7rem);position:relative;
}
.steps li::before{
  content:counter(s,decimal-leading-zero);
  font-family:var(--f-mono);font-size:.72rem;letter-spacing:.12em;color:var(--scale-deep);
  display:block;margin-bottom:.7rem;
}
.steps h3{margin-bottom:.55rem}
.steps p{margin:0;font-size:.96rem;color:var(--slate)}

/* ── signup ─────────────────────────────────── */

.band-signup{border-top:1px solid var(--line);background:var(--ink);color:var(--ground)}
.band-signup .h-lead{color:var(--white)}
.band-signup p{color:#B9C6C3}

.signup-in{
  display:grid;gap:var(--gap);grid-template-columns:1fr;align-items:center;
  padding:clamp(2.6rem,6vw,4.4rem) 0;
}
@media (min-width:860px){.signup-in{grid-template-columns:1fr 1fr}}
.signup-in > div p{max-width:42ch;margin:0}

.signup-row{display:flex;gap:.55rem;flex-wrap:wrap}
.signup input{
  flex:1 1 15rem;min-width:0;
  background:transparent;border:1px solid #3D4E4C;color:var(--white);
  padding:.85rem .95rem;font-family:var(--f-mono);font-size:.92rem;
}
.signup input::placeholder{color:#6D7E7C}
.signup input:focus-visible{border-color:var(--lcd)}
.signup button{
  font-family:var(--f-display);font-weight:800;font-stretch:88%;text-transform:uppercase;
  letter-spacing:.1em;font-size:.8rem;
  background:var(--lcd);color:var(--white);border:none;padding:.85rem 1.4rem;cursor:pointer;
  transition:background .16s ease;
}
.signup button:hover{background:#0C6A52}
.signup-msg{min-height:1.2rem;margin:.7rem 0 0;font-family:var(--f-mono);font-size:.8rem}
.signup-msg.ok{color:#7FE3C4}
.signup-msg.err{color:#E8A87F}
.signup-fine{font-size:.8rem;margin:.35rem 0 0}

/* ── footer ─────────────────────────────────── */

.foot{border-top:1px solid var(--line);padding:2.6rem 0 3.4rem}
.foot-mark{
  font-family:var(--f-display);font-weight:900;font-stretch:112%;text-transform:uppercase;
  font-size:1rem;margin:0 0 1rem;letter-spacing:-.01em;
}
.foot-note{font-size:.86rem;color:var(--slate);max-width:70ch;margin:0 0 .8rem}

/* ── motion ─────────────────────────────────── */

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