:root {
  --green: #3b961a;
  --green-dark: #2f7a14;
  --green-light: #efffe9;
  --white: #ffffff;
  --grey: #f2f2f2;
  --dark: #373a3c;

  --text: var(--dark);
  --muted: rgba(55, 58, 60, .72);
  --line: rgba(55, 58, 60, .12);
  --line-strong: rgba(55, 58, 60, .2);

  --radius: 10px;
  --radius-sm: 6px;
  --shadow-sm: 0 1px 2px rgba(55, 58, 60, .06), 0 2px 8px rgba(55, 58, 60, .05);
  --shadow-md: 0 8px 30px rgba(55, 58, 60, .10);
  --shadow-lg: 0 24px 60px rgba(55, 58, 60, .18);

  --header-h: 72px;
  --container: 1180px;
  --ease: cubic-bezier(.22, .61, .36, 1);

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.65;
  color: var(--text);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.is-locked { overflow: hidden; }

img, svg { display: block; max-width: 100%; }
h1, h2, h3, h4 { margin: 0; line-height: 1.2; color: var(--dark); letter-spacing: -.01em; }
p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }
a { color: var(--green); text-decoration: none; transition: color .2s var(--ease); }
a:hover { color: var(--green-dark); }
button { font: inherit; color: inherit; cursor: pointer; }
ul, ol { margin: 0; padding: 0; list-style: none; }
sub { font-size: .7em; }

:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 3px;
  border-radius: 4px;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow { max-width: 860px; }

.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 200;
  padding: 10px 16px;
  background: var(--green);
  color: var(--white);
  border-radius: var(--radius-sm);
  transition: top .2s var(--ease);
}
.skip-link:focus { top: 12px; color: var(--white); }

.muted { color: var(--muted); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .88);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s var(--ease), box-shadow .3s var(--ease);
}
.site-header.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 4px 20px rgba(55, 58, 60, .05);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  color: var(--dark);
}
.brand:hover { color: var(--dark); }
.brand-logo { height: 38px; width: auto; max-width: 180px; object-fit: contain; }

.main-nav ul { display: flex; gap: 4px; }
.main-nav a {
  position: relative;
  display: block;
  padding: 8px 14px;
  font-size: .95rem;
  font-weight: 500;
  color: var(--dark);
  border-radius: var(--radius-sm);
}
.main-nav a::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 3px;
  height: 2px;
  background: var(--green);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .35s var(--ease);
}
.main-nav a:hover { color: var(--green); }
.main-nav a:hover::after,
.main-nav a.is-active::after { transform: scaleX(1); }
.main-nav a.is-active { color: var(--green); }

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: var(--radius-sm);
  position: relative;
}
.nav-toggle span {
  position: absolute;
  left: 12px;
  right: 12px;
  height: 2px;
  background: var(--dark);
  border-radius: 2px;
  transition: transform .3s var(--ease), opacity .2s var(--ease), top .3s var(--ease);
}
.nav-toggle span:nth-child(1) { top: 15px; }
.nav-toggle span:nth-child(2) { top: 21px; }
.nav-toggle span:nth-child(3) { top: 27px; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { top: 21px; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { top: 21px; transform: rotate(-45deg); }

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  overflow: hidden;
}
.scroll-progress span {
  display: block;
  height: 100%;
  width: 100%;
  background: var(--green);
  transform: scaleX(0);
  transform-origin: left;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  font-size: .97rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease), transform .25s var(--ease), box-shadow .25s var(--ease);
}
.btn-primary { background: var(--green); color: var(--white); box-shadow: 0 6px 18px rgba(59, 150, 26, .25); }
.btn-primary:hover { background: var(--green-dark); color: var(--white); transform: translateY(-2px); box-shadow: 0 10px 24px rgba(59, 150, 26, .3); }
.btn-ghost { background: var(--white); color: var(--dark); border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--green); color: var(--green); transform: translateY(-2px); }

.hero {
  position: relative;
  padding: 72px 0 64px;
  background: radial-gradient(1000px 500px at 85% 10%, var(--green-light) 0%, rgba(239, 255, 233, 0) 70%), var(--white);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(700px 400px at 80% 20%, #000 0%, transparent 75%);
  -webkit-mask-image: radial-gradient(700px 400px at 80% 20%, #000 0%, transparent 75%);
  opacity: .5;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  align-items: center;
  gap: 48px;
}

.eyebrow {
  display: inline-block;
  margin-bottom: 16px;
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--green);
}

.hero h1 {
  font-size: clamp(2.1rem, 4.6vw, 3.4rem);
  font-weight: 750;
  line-height: 1.1;
  letter-spacing: -.025em;
  margin-bottom: 22px;
}

.lead {
  font-size: 1.15rem;
  color: var(--muted);
  max-width: 600px;
  margin-bottom: 32px;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 340px;
}
.hero-visual::before {
  content: "";
  position: absolute;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  border: 1px dashed rgba(59, 150, 26, .35);
  animation: spin 60s linear infinite;
}

.drop {
  width: 210px;
  height: auto;
  filter: drop-shadow(0 24px 40px rgba(59, 150, 26, .22));
  animation: float 6s ease-in-out infinite;
}
.wave { animation: wave 5s linear infinite; }
.wave-back { animation-duration: 8s; animation-direction: reverse; }
.wave-level { animation: level 9s ease-in-out infinite; }

.chip {
  position: absolute;
  padding: 7px 14px;
  font-size: .82rem;
  font-weight: 600;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
  white-space: nowrap;
  animation: float 7s ease-in-out infinite;
}
.chip::before {
  content: "";
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--green);
  vertical-align: 1px;
}
.chip-1 { top: 12%; left: 4%; animation-delay: -1s; }
.chip-2 { top: 46%; right: 0; animation-delay: -3s; }
.chip-3 { bottom: 8%; left: 12%; animation-delay: -5s; }

.facts {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-top: 64px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.fact {
  padding: 24px 26px;
  border-right: 1px solid var(--line);
}
.fact:last-child { border-right: 0; }
.fact strong {
  display: block;
  font-size: 1.3rem;
  color: var(--green);
  margin-bottom: 4px;
  letter-spacing: -.01em;
}
.fact span { font-size: .92rem; color: var(--muted); line-height: 1.5; }

.section { padding: 104px 0; }
.section-tinted { background: var(--grey); }
.section-dark { background: var(--dark); color: rgba(255, 255, 255, .82); }
.section-dark h2, .section-dark h3 { color: var(--white); }
.section-dark .eyebrow { color: #7fd35e; }

.section-head { max-width: 760px; margin-bottom: 56px; }
.section-head-center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head h2 {
  font-size: clamp(1.75rem, 3.2vw, 2.5rem);
  font-weight: 720;
  letter-spacing: -.02em;
  margin-bottom: 18px;
}
.section-head p { color: var(--muted); font-size: 1.08rem; }

.subsection { margin-top: 80px; }
.subhead { font-size: 1.4rem; font-weight: 700; margin-bottom: 28px; }

.cards { display: grid; gap: 24px; }
.cards-2 { grid-template-columns: repeat(2, 1fr); }
.cards-3 { grid-template-columns: repeat(3, 1fr); }

.card {
  position: relative;
  padding: 32px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .4s var(--ease), box-shadow .4s var(--ease), border-color .4s var(--ease);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(59, 150, 26, .35);
}
.card h3 { font-size: 1.18rem; font-weight: 700; margin-bottom: 12px; }
.card p { color: var(--muted); font-size: .98rem; }

.card-icon {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  margin-bottom: 22px;
  background: var(--green-light);
  border-radius: var(--radius-sm);
  transition: background .3s var(--ease);
}
.card-icon svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: var(--green);
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: stroke .3s var(--ease);
}
.card:hover .card-icon { background: var(--green); }
.card:hover .card-icon svg { stroke: var(--white); }

.card-wide { border-left: 3px solid var(--green); }

.card-dark {
  background: rgba(255, 255, 255, .04);
  border-color: rgba(255, 255, 255, .1);
}
.card-dark p { color: rgba(255, 255, 255, .72); }
.card-dark:hover { border-color: rgba(127, 211, 94, .45); box-shadow: 0 16px 40px rgba(0, 0, 0, .25); }

.note {
  display: flex;
  gap: 20px;
  margin-top: 40px;
  padding: 28px 32px;
  background: var(--green-light);
  border: 1px solid rgba(59, 150, 26, .2);
  border-radius: var(--radius);
}
.note h3 { font-size: 1.08rem; margin-bottom: 8px; }
.note p { color: var(--muted); font-size: .98rem; }
.note-icon {
  flex: 0 0 36px;
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  font-weight: 800;
  font-size: 1rem;
  color: var(--white);
  background: var(--green);
  border-radius: 50%;
}
.note-warn { background: var(--grey); border-color: var(--line); }
.note-warn .note-icon { background: var(--dark); }

.production {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 64px;
  align-items: start;
}

.column-viz {
  position: sticky;
  top: calc(var(--header-h) + 32px);
  padding: 28px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.viz-title {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 18px;
}
.column {
  display: flex;
  flex-direction: column;
  height: 380px;
  border: 2px solid var(--dark);
  border-radius: 40px 40px 10px 10px;
  overflow: hidden;
  background: var(--grey);
}
.fraction {
  position: relative;
  flex: 0 0 var(--h);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 0 20px;
  border-bottom: 1px dashed var(--line-strong);
  font-size: .88rem;
  transition: background .4s var(--ease);
}
.fraction:last-child { border-bottom: 0; }
.fraction span { font-weight: 650; }
.fraction small { color: var(--muted); font-size: .76rem; }
.fraction:nth-child(1) { --h: 14%; background: #fbfbfb; }
.fraction:nth-child(2) { --h: 18%; background: #f6f6f6; }
.fraction:nth-child(3) { --h: 16%; background: #efefef; }
.fraction:nth-child(4) { --h: 22%; }
.fraction:nth-child(5) { --h: 30%; background: #dcdddd; }

.fraction.is-target {
  background: var(--green);
  color: var(--white);
  overflow: hidden;
}
.fraction.is-target small { color: rgba(255, 255, 255, .85); }
.fraction.is-target::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(100deg, transparent 30%, rgba(255, 255, 255, .25) 50%, transparent 70%);
  transform: translateX(-100%);
  animation: shine 4.5s var(--ease) infinite;
}

.column-heat {
  display: flex;
  justify-content: center;
  gap: 14px;
  margin-top: 10px;
  height: 20px;
}
.column-heat span {
  width: 10px;
  height: 18px;
  background: linear-gradient(to top, #e8a33d, #f6d27a);
  border-radius: 50% 50% 40% 40%;
  animation: flame 1.6s ease-in-out infinite;
  transform-origin: bottom;
}
.column-heat span:nth-child(2) { animation-delay: -.5s; }
.column-heat span:nth-child(3) { animation-delay: -1s; }

.viz-caption { margin-top: 16px; font-size: .88rem; color: var(--muted); }

.timeline { position: relative; }
.timeline::before {
  content: "";
  position: absolute;
  left: 21px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--line-strong);
}
.timeline::after {
  content: "";
  position: absolute;
  left: 21px;
  top: 8px;
  width: 2px;
  height: var(--timeline-progress, 0%);
  max-height: calc(100% - 16px);
  background: var(--green);
  transition: height .2s linear;
}
.timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 24px;
  padding-bottom: 40px;
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-dot {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  font-weight: 700;
  font-size: .95rem;
  background: var(--white);
  color: var(--dark);
  border: 2px solid var(--line-strong);
  border-radius: 50%;
  transition: background .4s var(--ease), color .4s var(--ease), border-color .4s var(--ease);
}
.timeline-item.is-passed .timeline-dot {
  background: var(--green);
  border-color: var(--green);
  color: var(--white);
}
.timeline-item h3 { font-size: 1.15rem; margin: 9px 0 8px; }
.timeline-item p { color: var(--muted); font-size: .98rem; }

.steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}
.step {
  position: relative;
  padding: 28px 22px 26px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .4s var(--ease), box-shadow .4s var(--ease), border-color .4s var(--ease);
}
.step::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 3px;
  background: var(--green);
  border-radius: var(--radius) var(--radius) 0 0;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .5s var(--ease);
}
.step:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.step:hover::before { transform: scaleX(1); }
.step-num {
  display: block;
  font-size: 1.9rem;
  font-weight: 800;
  color: var(--green);
  opacity: .9;
  margin-bottom: 14px;
  letter-spacing: -.03em;
}
.step h3 { font-size: 1.05rem; margin-bottom: 10px; }
.step p { font-size: .92rem; color: var(--muted); }

.factor {
  padding: 26px 28px;
  background: var(--grey);
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: background .35s var(--ease), border-color .35s var(--ease), transform .35s var(--ease);
}
.factor:hover { background: var(--green-light); border-color: rgba(59, 150, 26, .25); transform: translateY(-3px); }
.factor h4 {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.05rem;
  margin-bottom: 10px;
}
.factor h4::before {
  content: "";
  width: 8px;
  height: 8px;
  background: var(--green);
  border-radius: 2px;
  transform: rotate(45deg);
}
.factor p { font-size: .95rem; color: var(--muted); }

.checklist-wrap {
  display: grid;
  grid-template-columns: 1fr 1.6fr;
  gap: 48px;
  padding: 44px;
  background: var(--green-light);
  border-radius: var(--radius);
  border: 1px solid rgba(59, 150, 26, .18);
}
.checklist-wrap .subhead { margin-bottom: 12px; }
.checklist { display: grid; gap: 14px; }
.checklist li {
  position: relative;
  padding-left: 36px;
  font-size: .98rem;
}
.checklist li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 2px;
  width: 22px;
  height: 22px;
  background: var(--green);
  border-radius: 50%;
}
.checklist li::after {
  content: "";
  position: absolute;
  left: 8px;
  top: 6px;
  width: 6px;
  height: 11px;
  border: solid var(--white);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

.calc {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.tabs {
  position: relative;
  display: flex;
  border-bottom: 1px solid var(--line);
  background: var(--white);
}
.tab {
  flex: 0 0 auto;
  padding: 20px 28px;
  background: none;
  border: 0;
  font-weight: 600;
  font-size: .98rem;
  color: var(--muted);
  transition: color .25s var(--ease);
}
.tab:hover, .tab.is-active { color: var(--dark); }
.tab-indicator {
  position: absolute;
  bottom: -1px;
  left: 0;
  height: 2px;
  background: var(--green);
  transition: transform .4s var(--ease), width .4s var(--ease);
}

.tab-panel { padding: 40px; }
.tab-panel.is-active { animation: fadeUp .5s var(--ease); }

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 48px;
  align-items: center;
}

.calc-form { display: grid; gap: 22px; }
.field { display: grid; gap: 8px; }
.field > span { font-size: .92rem; font-weight: 600; }
.field output { color: var(--green); font-weight: 700; }

.field input[type="number"],
.field select {
  width: 100%;
  padding: 13px 16px;
  font: inherit;
  font-size: 1rem;
  color: var(--dark);
  background: var(--grey);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  transition: border-color .2s var(--ease), background .2s var(--ease), box-shadow .2s var(--ease);
  appearance: none;
  -webkit-appearance: none;
}
.field select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23373a3c' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  background-size: 18px;
  padding-right: 44px;
}
.field input[type="number"]:focus,
.field select:focus {
  outline: none;
  background-color: var(--white);
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(59, 150, 26, .12);
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  margin: 10px 0;
  border-radius: 3px;
  background: linear-gradient(to right, var(--green) 0%, var(--green) var(--val, 25%), var(--grey) var(--val, 25%), var(--grey) 100%);
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--white);
  border: 2px solid var(--green);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: transform .2s var(--ease);
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.12); }
input[type="range"]::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--white);
  border: 2px solid var(--green);
  cursor: pointer;
}

.hint { font-size: .86rem; color: var(--muted); margin: -6px 0 0; }

.switch {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: .95rem;
  cursor: pointer;
  user-select: none;
}
.switch input { position: absolute; opacity: 0; pointer-events: none; }
.switch-track {
  position: relative;
  flex: 0 0 44px;
  height: 24px;
  background: var(--line-strong);
  border-radius: 999px;
  transition: background .3s var(--ease);
}
.switch-track::after {
  content: "";
  position: absolute;
  top: 3px;
  left: 3px;
  width: 18px;
  height: 18px;
  background: var(--white);
  border-radius: 50%;
  box-shadow: 0 1px 3px rgba(0, 0, 0, .2);
  transition: transform .3s var(--ease);
}
.switch input:checked + .switch-track { background: var(--green); }
.switch input:checked + .switch-track::after { transform: translateX(20px); }
.switch input:focus-visible + .switch-track { outline: 2px solid var(--green); outline-offset: 3px; }

.calc-result {
  display: flex;
  align-items: center;
  gap: 36px;
  padding: 32px;
  background: var(--grey);
  border-radius: var(--radius);
}
#panel-usage .calc-result { flex-direction: column; align-items: stretch; }

.tank { flex: 0 0 120px; }
.tank-body {
  position: relative;
  height: 220px;
  border: 2px solid var(--dark);
  border-radius: 18px;
  background: var(--white);
  overflow: hidden;
}
.tank-fill, .tank-order {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  transition: height .7s var(--ease), bottom .7s var(--ease);
}
.tank-fill { background: var(--green); height: 25%; }
.tank-order {
  background: repeating-linear-gradient(-45deg, rgba(59, 150, 26, .35) 0 6px, rgba(59, 150, 26, .18) 6px 12px);
  border-top: 2px dashed var(--green);
}
.tank-max {
  position: absolute;
  left: 0;
  right: 0;
  top: 5%;
  border-top: 1px dashed var(--dark);
}
.tank-max span {
  position: absolute;
  right: 6px;
  top: 2px;
  font-size: .7rem;
  font-weight: 700;
  color: var(--dark);
}

.results { flex: 1; display: grid; gap: 18px; margin: 0; }
.results div { border-bottom: 1px solid var(--line); padding-bottom: 14px; }
.results div:last-child { border-bottom: 0; padding-bottom: 0; }
.results dt { font-size: .85rem; color: var(--muted); margin-bottom: 2px; }
.results dd { margin: 0; font-size: 1.2rem; font-weight: 700; }
.result-main dd {
  font-size: clamp(1.7rem, 3vw, 2.2rem);
  color: var(--green);
  letter-spacing: -.02em;
}

.bar-compare { display: grid; gap: 10px; margin-top: 26px; }
.bar-row {
  display: grid;
  grid-template-columns: 96px 1fr;
  align-items: center;
  gap: 12px;
  font-size: .82rem;
  color: var(--muted);
}
.bar-row:nth-child(1) { --w: 35%; }
.bar-row:nth-child(2) { --w: 62%; }
.bar-row:nth-child(3) { --w: 92%; }
.bar { height: 8px; background: rgba(55, 58, 60, .08); border-radius: 4px; overflow: hidden; }
.bar i {
  display: block;
  height: 100%;
  width: var(--w);
  background: var(--green);
  border-radius: 4px;
  opacity: .35;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 1s var(--ease), opacity .3s var(--ease);
}
.bar-row.is-current { color: var(--dark); font-weight: 600; }
.bar-row.is-current i { opacity: 1; }
.calc.is-visible .bar i { transform: scaleX(1); }

.accordion { border-top: 1px solid var(--line); }
.acc-item { border-bottom: 1px solid var(--line); }
.acc-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: 100%;
  padding: 24px 0;
  background: none;
  border: 0;
  text-align: left;
  font-size: 1.08rem;
  font-weight: 600;
  color: var(--dark);
  transition: color .25s var(--ease);
}
.acc-trigger:hover { color: var(--green); }
.acc-icon {
  position: relative;
  flex: 0 0 32px;
  width: 32px;
  height: 32px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  transition: background .3s var(--ease), border-color .3s var(--ease), transform .4s var(--ease);
}
.acc-icon::before, .acc-icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 12px;
  height: 2px;
  background: var(--dark);
  transform: translate(-50%, -50%);
  transition: transform .4s var(--ease), background .3s var(--ease);
}
.acc-icon::after { transform: translate(-50%, -50%) rotate(90deg); }
.acc-trigger[aria-expanded="true"] .acc-icon { background: var(--green); border-color: var(--green); transform: rotate(180deg); }
.acc-trigger[aria-expanded="true"] .acc-icon::before,
.acc-trigger[aria-expanded="true"] .acc-icon::after { background: var(--white); }
.acc-trigger[aria-expanded="true"] .acc-icon::after { transform: translate(-50%, -50%) rotate(0deg); }

.acc-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows .45s var(--ease);
}
.acc-panel > .acc-content { overflow: hidden; }
.acc-item.is-open .acc-panel { grid-template-rows: 1fr; }
.acc-content p {
  padding: 0 56px 26px 0;
  color: var(--muted);
}

.site-footer {
  background: var(--grey);
  border-top: 1px solid var(--line);
  padding-top: 64px;
  font-size: .95rem;
}
.footer-inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
}
.footer-brand p { margin-top: 16px; color: var(--muted); max-width: 380px; }
.footer-col h4 {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 16px;
}
.footer-col ul { display: grid; gap: 8px; }
.footer-col a { color: var(--dark); }
.footer-col a:hover { color: var(--green); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 24px;
  padding-bottom: 28px;
  border-top: 1px solid var(--line);
  font-size: .88rem;
  color: var(--muted);
}
.footer-bottom p { margin: 0; }
.legal-links { display: flex; gap: 8px; flex-wrap: wrap; }
.legal-links button {
  padding: 6px 12px;
  background: none;
  border: 0;
  border-radius: var(--radius-sm);
  font-size: .88rem;
  font-weight: 500;
  color: var(--dark);
  transition: background .2s var(--ease), color .2s var(--ease);
}
.legal-links button:hover { background: var(--white); color: var(--green); }

.to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 90;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  padding: 0;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 50%;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity .3s var(--ease), transform .3s var(--ease), visibility .3s, background .2s var(--ease);
}
.to-top.is-visible { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--green); }
.to-top svg { width: 20px; height: 20px; fill: none; stroke: var(--dark); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.to-top:hover svg { stroke: var(--white); }

.modal {
  position: fixed;
  inset: 0;
  z-index: 300;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.modal[hidden] { display: none; }
.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(55, 58, 60, .55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity .35s var(--ease);
}
.modal-dialog {
  position: relative;
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: 780px;
  max-height: calc(100vh - 48px);
  max-height: calc(100dvh - 48px);
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(24px) scale(.98);
  transition: opacity .35s var(--ease), transform .35s var(--ease);
}
.modal.is-open .modal-backdrop { opacity: 1; }
.modal.is-open .modal-dialog { opacity: 1; transform: none; }

.modal-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 22px 28px;
  border-bottom: 1px solid var(--line);
}
.modal-head h2 { font-size: 1.3rem; font-weight: 700; }
.modal-close {
  flex: 0 0 40px;
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  padding: 0;
  background: var(--grey);
  border: 0;
  border-radius: 50%;
  transition: background .2s var(--ease), transform .3s var(--ease);
}
.modal-close:hover { background: var(--green-light); transform: rotate(90deg); }
.modal-close svg { width: 18px; height: 18px; fill: none; stroke: var(--dark); stroke-width: 2; stroke-linecap: round; }

.modal-body {
  padding: 28px;
  overflow-y: auto;
  overscroll-behavior: contain;
}
.modal-body::-webkit-scrollbar { width: 8px; }
.modal-body::-webkit-scrollbar-thumb { background: var(--line-strong); border-radius: 4px; }

.legal { font-size: .95rem; }
.legal h3 {
  font-size: 1rem;
  font-weight: 700;
  margin: 26px 0 8px;
}
.legal h3:first-child { margin-top: 0; }
.legal p, .legal li { color: var(--muted); }
.legal ul { margin: 0 0 1em; padding-left: 0; }
.legal li { position: relative; padding-left: 20px; margin-bottom: 4px; }
.legal li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: .7em;
  width: 6px;
  height: 6px;
  background: var(--green);
  border-radius: 50%;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
  transition-delay: var(--delay, 0s);
}
.reveal.is-visible { opacity: 1; transform: none; }
.no-js .reveal { opacity: 1; transform: none; }

@keyframes wave { from { transform: translateX(0); } to { transform: translateX(-100px); } }
@keyframes level { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-14px); } }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-10px); } }
@keyframes spin { to { transform: rotate(360deg); } }
@keyframes shine { 0% { transform: translateX(-100%); } 60%, 100% { transform: translateX(100%); } }
@keyframes flame { 0%, 100% { transform: scaleY(1); opacity: .9; } 50% { transform: scaleY(.65); opacity: .6; } }
@keyframes fadeUp { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }

@media (max-width: 1080px) {
  .steps { grid-template-columns: repeat(3, 1fr); }
  .production { grid-template-columns: 320px 1fr; gap: 40px; }
}

@media (max-width: 960px) {
  :root { --header-h: 64px; }

  .site-header {
    background: var(--white);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }

  .nav-toggle { display: block; }
  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--white);
    padding: 24px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity .3s var(--ease), transform .3s var(--ease), visibility .3s;
  }
  .main-nav.is-open { opacity: 1; visibility: visible; transform: none; }
  .main-nav ul { flex-direction: column; gap: 0; }
  .main-nav li { border-bottom: 1px solid var(--line); }
  .main-nav a { padding: 18px 4px; font-size: 1.15rem; }
  .main-nav a::after { display: none; }

  .hero { padding: 48px 0; }
  .hero-inner { grid-template-columns: 1fr; gap: 24px; }
  .hero-visual { min-height: 300px; order: -1; }
  .hero-visual::before { width: 260px; height: 260px; }
  .drop { width: 170px; }
  .facts { grid-template-columns: repeat(2, 1fr); margin-top: 40px; }
  .fact:nth-child(2) { border-right: 0; }
  .fact:nth-child(-n+2) { border-bottom: 1px solid var(--line); }

  .section { padding: 80px 0; }
  .cards-3 { grid-template-columns: 1fr 1fr; }
  .production { grid-template-columns: 1fr; }
  .column-viz { position: relative; top: 0; max-width: 460px; }
  .calc-grid { grid-template-columns: 1fr; gap: 32px; }
  .checklist-wrap { grid-template-columns: 1fr; gap: 24px; padding: 32px; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  body { font-size: 16px; }
  .container { padding: 0 16px; }
  .hero-actions .btn { flex: 1 1 100%; }
  .chip { font-size: .74rem; padding: 6px 11px; }
  .chip-2 { right: 2%; }

  .facts { grid-template-columns: 1fr; }
  .fact { border-right: 0; border-bottom: 1px solid var(--line); }
  .fact:last-child { border-bottom: 0; }

  .section { padding: 64px 0; }
  .section-head { margin-bottom: 40px; }
  .subsection { margin-top: 56px; }
  .cards-2, .cards-3, .steps { grid-template-columns: 1fr; }
  .card { padding: 26px; }
  .note { flex-direction: column; gap: 14px; padding: 24px; }

  .tab { flex: 1; padding: 16px 12px; }
  .tab-panel { padding: 24px 16px; }
  .calc-result { flex-direction: column; align-items: stretch; padding: 24px; gap: 24px; }
  .tank { align-self: center; flex-basis: auto; width: 110px; }
  .tank-body { height: 180px; }

  .acc-content p { padding-right: 0; }
  .footer-inner { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }

  .modal { padding: 0; align-items: flex-end; }
  .modal-dialog { max-height: 92vh; max-height: 92dvh; border-radius: var(--radius) var(--radius) 0 0; }
  .modal-head, .modal-body { padding-left: 20px; padding-right: 20px; }
  .to-top { right: 16px; bottom: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
  .reveal { opacity: 1; transform: none; }
}