:root {
  --color-primary: #1a56b0;
  --color-secondary: #b83227;
  --color-accent: #1a56b0;
  --color-bg: #f2f5f7;
  --color-text: #0f2233;

  --color-cold: #1a56b0;
  --color-cold-deep: #134189;
  --color-cold-wash: #e1ebf8;
  --color-hot: #b83227;
  --color-hot-wash: #f8e6e3;
  --color-muted: #47596a;
  --color-surface: #ffffff;
  --color-rule: #cfd8df;
  --color-ink: #0f2233;
  --color-on-ink: #f2f5f7;
  --color-on-ink-muted: #b9c6d1;
  --color-on-ink-rule: #2c4257;
  --color-on-cold: #ffffff;
  --color-star: #8a5a00;
  --color-shadow: rgba(15, 34, 51, 0.10);
  --color-header: rgba(242, 245, 247, 0.92);

  --rail: 200px;
  --radius-s: 10px;
  --radius-m: 16px;
  --radius-l: 26px;
  --font-sans: "Avenir Next", "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

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

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.6;
}

img { max-width: 100%; display: block; }

a { color: var(--color-cold); text-underline-offset: 3px; }
a:hover { color: var(--color-cold-deep); }
a:focus-visible, .btn:focus-visible {
  outline: 3px solid var(--color-cold);
  outline-offset: 3px;
  border-radius: 6px;
}

h1, h2, h3 { line-height: 1.08; letter-spacing: -0.02em; margin: 0; font-weight: 700; }
h1 { font-size: clamp(2.3rem, 6.2vw, 4.3rem); margin-bottom: 16px; }
h2 { font-size: clamp(1.7rem, 3.6vw, 2.5rem); margin-bottom: 12px; }
h3 { font-size: 1.15rem; letter-spacing: -0.01em; margin-bottom: 6px; }
p { margin: 0 0 16px; }
.lede { font-size: clamp(1.05rem, 1.7vw, 1.25rem); color: var(--color-muted); max-width: 56ch; }

.wrap { max-width: 1140px; margin: 0 auto; padding: 0 20px; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--color-header);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-rule);
}
.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  flex-wrap: wrap;
  padding-top: 8px;
  padding-bottom: 8px;
}
.header-phone {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  white-space: nowrap;
}
.header-phone span { color: var(--color-muted); font-weight: 500; margin-right: 8px; font-family: var(--font-sans); }
.wordmark {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  min-height: 44px;
  padding-top: 10px;
  color: var(--color-text);
  text-decoration: none;
  font-weight: 600;
  white-space: nowrap;
}
.wordmark b { font-size: 1.35rem; letter-spacing: -0.03em; font-weight: 800; }
.site-nav { display: flex; gap: 4px; flex-wrap: wrap; }
.site-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border-radius: var(--radius-s);
  color: var(--color-text);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.97rem;
}
.site-nav a:hover { background: var(--color-cold-wash); }
.site-nav a[aria-current="page"] { background: var(--color-ink); color: var(--color-on-ink); }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 24px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 1rem;
  text-decoration: none;
  border: 2px solid var(--color-cold);
  transition: background-color 0.15s ease, color 0.15s ease;
}
.btn-solid { background: var(--color-cold); color: var(--color-on-cold); }
.btn-solid:hover { background: var(--color-cold-deep); border-color: var(--color-cold-deep); color: var(--color-on-cold); }
.btn-line { background: transparent; color: var(--color-cold); }
.btn-line:hover { background: var(--color-cold-wash); }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }

/* ---------- the route: cold line, hot line, stops ---------- */
.stop {
  position: relative;
  padding: 52px 0 52px var(--rail);
}
.stop::before,
.stop.hot::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  width: 4px;
}
.stop::before { left: 16px; background: var(--color-cold); }
.stop.hot::after { left: 30px; background: var(--color-hot); }
.stop.heater::after { top: 60px; border-radius: 4px 4px 0 0; }
.stop.first::before { top: 60px; border-radius: 4px 4px 0 0; }
.stop.end::before, .stop.end::after { bottom: auto; height: 62px; }

.node {
  position: absolute;
  left: 10px;
  top: 54px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 4px solid var(--color-ink);
  z-index: 1;
}
.heater .node::after {
  content: "";
  position: absolute;
  left: 100%;
  top: 2px;
  width: 12px;
  height: 4px;
  background: var(--color-hot);
}
.end .node {
  width: 30px;
  border-radius: 8px;
  background: var(--color-ink);
}
.stop-label {
  position: absolute;
  left: 52px;
  top: 49px;
  width: calc(var(--rail) - 68px);
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.35;
  font-weight: 600;
  color: var(--color-muted);
}
.stop-label span {
  display: block;
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.82rem;
}

/* ---------- hero ---------- */
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  gap: 40px;
  align-items: start;
}
.rating {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 24px 0 0;
  padding: 8px 16px;
  border-radius: 999px;
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  font-size: 0.95rem;
  font-weight: 600;
}
.rating .stars { color: var(--color-star); letter-spacing: 2px; }
.photo { margin: 0; }
.photo img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  border-radius: var(--radius-l);
  box-shadow: 0 18px 40px var(--color-shadow);
}
.photo figcaption { margin-top: 10px; font-size: 0.95rem; color: var(--color-text); }
.photo small { display: block; font-size: 0.8rem; color: var(--color-muted); }

/* ---------- about ---------- */
.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: 40px;
  align-items: start;
}
.facts {
  margin: 0;
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-m);
  padding: 6px 22px;
}
.facts div {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 12px;
  padding: 14px 0;
  border-bottom: 1px solid var(--color-rule);
}
.facts div:last-child { border-bottom: 0; }
.facts dt { color: var(--color-muted); font-size: 0.92rem; }
.facts dd { margin: 0; font-weight: 600; }
.facts a { display: inline-flex; align-items: center; min-height: 34px; }

/* ---------- hot / cold split ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-top: 28px;
}
.side { padding: 24px 24px 12px; }
.side.cold { background: var(--color-cold-wash); border-radius: var(--radius-l) var(--radius-s) var(--radius-s) var(--radius-l); }
.side.warm { background: var(--color-hot-wash); border-radius: var(--radius-s) var(--radius-l) var(--radius-l) var(--radius-s); }
.side h3 { font-size: 1.3rem; margin-bottom: 10px; }
.side.cold h3 { color: var(--color-cold-deep); }
.side.warm h3 { color: var(--color-hot); }
.side ul { margin: 0; padding: 0; list-style: none; }
.side li { padding: 10px 0; border-top: 1px solid var(--color-rule); }
.note { margin-top: 20px; color: var(--color-muted); max-width: 62ch; }
.note a, .rows dd a { display: inline-block; padding: 7px 0; }

/* ---------- rows (signs, materials) ---------- */
.rows { margin: 28px 0 0; border-top: 2px solid var(--color-ink); }
.rows > div {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.6fr);
  gap: 8px 32px;
  padding: 18px 0;
  border-bottom: 1px solid var(--color-rule);
}
.rows dt { font-weight: 700; font-size: 1.1rem; letter-spacing: -0.01em; }
.rows dt small { display: block; font-weight: 500; font-size: 0.88rem; color: var(--color-muted); letter-spacing: 0; }
.rows dd { margin: 0; color: var(--color-muted); }
.tag {
  display: inline-block;
  margin-top: 6px;
  padding: 2px 10px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
}
.tag.old { background: var(--color-hot-wash); color: var(--color-hot); }
.tag.new { background: var(--color-cold-wash); color: var(--color-cold-deep); }

/* ---------- close panel ---------- */
.panel {
  background: var(--color-ink);
  color: var(--color-on-ink);
  border-radius: var(--radius-l);
  padding: clamp(28px, 5vw, 52px);
}
.panel h2 { color: var(--color-on-ink); }
.panel p { color: var(--color-on-ink-muted); max-width: 52ch; }
.big-phone {
  display: inline-flex;
  align-items: center;
  min-height: 56px;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 6.4vw, 3.4rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--color-on-ink);
  text-decoration-thickness: 3px;
  text-underline-offset: 8px;
  white-space: nowrap;
}
.big-phone:hover { color: var(--color-on-ink-muted); }
.panel-foot {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 32px;
  margin-top: 26px;
  padding-top: 18px;
  border-top: 1px solid var(--color-on-ink-rule);
  color: var(--color-on-ink-muted);
}
.panel-foot a { color: var(--color-on-ink); display: inline-flex; align-items: center; min-height: 34px; }

/* ---------- inner pages ---------- */
.page-head { padding: 56px 0 36px; }
.block { padding: 0 0 60px; }
.steps { list-style: none; margin: 28px 0 0; padding: 0; counter-reset: step; }
.steps li {
  position: relative;
  counter-increment: step;
  padding: 0 0 30px 68px;
}
.steps li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: var(--color-ink);
  color: var(--color-on-ink);
  font-family: var(--font-mono);
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1;
}
.steps li::after {
  content: "";
  position: absolute;
  left: 20px;
  top: 44px;
  bottom: 0;
  width: 4px;
  background: var(--color-cold);
}
.steps li:last-child { padding-bottom: 0; }
.steps li:last-child::after { display: none; }
.steps p { margin: 0; color: var(--color-muted); max-width: 60ch; }
.steps h3 { padding-top: 9px; }

.two-col {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 48px;
  align-items: start;
}
.ask {
  background: var(--color-surface);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-m);
  padding: 26px 26px 14px;
}
.ask ul { margin: 14px 0 0; padding: 0; list-style: none; }
.ask li {
  position: relative;
  padding: 11px 0 11px 28px;
  border-top: 1px solid var(--color-rule);
}
.ask li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--color-cold);
  font-weight: 700;
}
.contact-card {
  background: var(--color-ink);
  color: var(--color-on-ink);
  border-radius: var(--radius-l);
  padding: clamp(26px, 4vw, 40px);
}
.contact-card h2 { color: var(--color-on-ink); font-size: 1.3rem; margin-bottom: 4px; }
.contact-card p, .contact-card address { color: var(--color-on-ink-muted); font-style: normal; margin: 0 0 6px; }
.contact-card .group { padding: 20px 0; border-top: 1px solid var(--color-on-ink-rule); }
.contact-card .group:first-child { padding-top: 0; border-top: 0; }
.contact-card .group:last-child { padding-bottom: 0; }
.contact-card .big-phone { font-size: clamp(1.6rem, 5.4vw, 2.5rem); }
.contact-card .btn-line { color: var(--color-on-ink); border-color: var(--color-on-ink-muted); margin-top: 10px; }
.contact-card .btn-line:hover { background: var(--color-on-ink-rule); }
.contact-card .stars { color: var(--color-on-ink); letter-spacing: 2px; }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--color-rule);
  padding: 32px 0 40px;
  font-size: 0.93rem;
  color: var(--color-muted);
}
.footer-row { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px 40px; }
.site-footer p { margin: 0 0 4px; }
.site-footer strong { color: var(--color-text); }
.site-footer a { display: inline-flex; align-items: center; min-height: 34px; margin-right: 16px; }

/* ---------- motion ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.js .reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .btn { transition: none; }
}

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  :root { --rail: 46px; }
  .stop { padding-top: 40px; padding-bottom: 40px; }
  .stop-label { position: static; width: auto; margin-bottom: 8px; }
  .stop-label span { display: inline; margin-right: 6px; }
  .node { top: 42px; }
  .stop.heater::after, .stop.first::before { top: 48px; }
  .stop.end::before, .stop.end::after { height: 50px; }
  .hero-grid, .about-grid, .two-col { grid-template-columns: 1fr; gap: 28px; }
  .photo img { aspect-ratio: 16 / 10; }
  .page-head { padding: 40px 0 28px; }
  .block { padding-bottom: 48px; }
}

@media (max-width: 620px) {
  body { font-size: 16px; }
  .wrap { padding: 0 16px; }
  .site-header { position: static; }
  .header-row { gap: 0 16px; }
  .header-phone span { display: none; }
  .site-nav { width: 100%; margin: 0 -10px; }
  .site-nav a { padding: 0 10px; }
  .split { grid-template-columns: 1fr; }
  .side.cold, .side.warm { border-radius: var(--radius-m); }
  .rows > div { grid-template-columns: 1fr; }
  .facts div { grid-template-columns: 84px 1fr; }
  .btn-row .btn { width: 100%; }
  .steps li { padding-left: 60px; }
}