:root {
  --color-bg: #fbf6ee;
  --color-surface: #ffffff;
  --color-text: #2b1f17;
  --color-muted: #6b5a4a;
  --color-accent: #b3502b;
  --color-accent-dark: #8b3b1d;
  --color-line: #e6dbcb;
  --shadow-sm: 0 1px 2px rgba(43, 31, 23, 0.06);
  --shadow-md: 0 6px 24px rgba(43, 31, 23, 0.08);
  --radius: 14px;
  --max-w: 1140px;
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  font-size: 17px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--color-accent-dark); text-decoration: none; transition: color 0.15s; }
a:hover { color: var(--color-accent); text-decoration: underline; }

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow-sm);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 18px;
  padding-bottom: 18px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.2px;
  color: var(--color-text);
}

.brand:hover { color: var(--color-accent-dark); text-decoration: none; }

.brand-mark {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-dark));
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 800;
  font-size: 18px;
  letter-spacing: 0.5px;
  flex: 0 0 auto;
}

.brand-text { line-height: 1.1; }
.brand-text small {
  display: block;
  font-weight: 500;
  font-size: 11px;
  letter-spacing: 1.5px;
  color: var(--color-muted);
  text-transform: uppercase;
}

.nav {
  display: flex;
  gap: 6px;
}
.nav a {
  padding: 8px 14px;
  border-radius: 8px;
  color: var(--color-muted);
  font-weight: 500;
  font-size: 15px;
}
.nav a:hover {
  background: var(--color-bg);
  color: var(--color-text);
  text-decoration: none;
}
.nav a.active {
  color: var(--color-accent-dark);
  background: rgba(179, 80, 43, 0.08);
}

.nav-toggle {
  display: none;
  border: none;
  background: transparent;
  padding: 8px;
  cursor: pointer;
  color: var(--color-text);
}

/* Hero */
.hero {
  position: relative;
  min-height: 540px;
  display: flex;
  align-items: center;
  color: #fff;
  background: #1a120c;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(26, 18, 12, 0.55) 0%, rgba(26, 18, 12, 0.78) 100%),
              url("img/hero-heater.jpg") center/cover no-repeat;
}
.hero .container { position: relative; padding-top: 90px; padding-bottom: 90px; }
.hero h1 {
  font-size: clamp(2.2rem, 4.5vw, 3.6rem);
  margin: 0 0 18px;
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.5px;
}
.hero p.lead {
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  max-width: 620px;
  color: rgba(255, 255, 255, 0.85);
  margin: 0 0 32px;
}
.hero-cta {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 13px 28px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.2px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.1s, background 0.15s, border-color 0.15s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  background: var(--color-accent);
  color: #fff;
}
.btn-primary:hover { background: var(--color-accent-dark); color: #fff; }
.btn-ghost {
  background: transparent;
  border-color: rgba(255, 255, 255, 0.4);
  color: #fff;
}
.btn-ghost:hover { border-color: #fff; background: rgba(255, 255, 255, 0.08); color: #fff; }

/* Page header (non-home) */
.page-header {
  padding: 64px 0 48px;
  text-align: center;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
}
.page-header .eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--color-accent-dark);
  margin-bottom: 12px;
}
.page-header h1 {
  font-size: clamp(2rem, 3.5vw, 2.8rem);
  margin: 0 0 14px;
  letter-spacing: -0.5px;
}
.page-header p {
  max-width: 680px;
  margin: 0 auto;
  color: var(--color-muted);
  font-size: 17px;
}

/* Sections */
section { padding: 72px 0; }
section.tight { padding: 48px 0; }

h2 {
  font-size: clamp(1.5rem, 2.4vw, 2rem);
  margin: 0 0 18px;
  letter-spacing: -0.3px;
}
h3 {
  font-size: 1.2rem;
  margin: 28px 0 10px;
}

p { margin: 0 0 16px; }
ul, ol { margin: 0 0 16px; padding-left: 22px; }
li { margin-bottom: 6px; }

.prose { max-width: 760px; }
.prose img {
  border-radius: var(--radius);
  margin: 24px 0;
  box-shadow: var(--shadow-md);
}

.lead-text {
  font-size: 1.15rem;
  color: var(--color-muted);
  margin-bottom: 28px;
}

.figure {
  margin: 28px 0;
}
.figure img {
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
}
.figure figcaption {
  margin-top: 10px;
  font-size: 14px;
  color: var(--color-muted);
  text-align: center;
}

/* Tile grid (homepage cards) */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.card {
  background: var(--color-surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-line);
  display: flex;
  flex-direction: column;
  transition: transform 0.15s, box-shadow 0.15s;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.card .card-img {
  aspect-ratio: 16 / 10;
  background-size: cover;
  background-position: center;
}
.card .card-body {
  padding: 20px 22px 24px;
}
.card h3 {
  margin: 0 0 8px;
  font-size: 1.15rem;
}
.card p {
  margin: 0 0 14px;
  color: var(--color-muted);
  font-size: 15px;
}
.card .card-link {
  font-weight: 600;
  font-size: 14px;
  color: var(--color-accent-dark);
}

/* Two-column feature */
.two-col {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
  align-items: center;
}
.two-col.reverse { grid-template-columns: 1fr 1.1fr; }
.two-col img { border-radius: var(--radius); box-shadow: var(--shadow-md); }

@media (max-width: 820px) {
  .two-col, .two-col.reverse { grid-template-columns: 1fr; gap: 28px; }
}

/* Step list */
.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
}
.steps > li {
  counter-increment: step;
  position: relative;
  padding-left: 64px;
  margin-bottom: 28px;
}
.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: -2px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #fff;
  font-weight: 700;
  font-size: 18px;
  display: grid;
  place-items: center;
}
.steps h3 { margin: 4px 0 6px; }

/* Callout */
.callout {
  background: #fff5e9;
  border-left: 4px solid var(--color-accent);
  padding: 18px 22px;
  border-radius: 6px;
  margin: 28px 0;
}
.callout.warn {
  background: #fef2f2;
  border-left-color: #b91c1c;
}
.callout strong { display: block; margin-bottom: 4px; }

/* Pricing / info table */
.info-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  background: var(--color-surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-line);
}
.info-table th, .info-table td {
  text-align: left;
  padding: 14px 18px;
  border-bottom: 1px solid var(--color-line);
}
.info-table th {
  background: #f5ecdc;
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.3px;
  color: var(--color-muted);
  text-transform: uppercase;
}
.info-table tr:last-child td { border-bottom: none; }

/* Footer */
.site-footer {
  background: #2b1f17;
  color: #d8c8b3;
  padding: 56px 0 32px;
  margin-top: 80px;
}
.site-footer h4 {
  font-size: 14px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: #fff;
  margin: 0 0 14px;
}
.site-footer .footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
@media (max-width: 720px) {
  .site-footer .footer-grid { grid-template-columns: 1fr; gap: 28px; }
}
.site-footer p { margin: 0 0 8px; font-size: 15px; color: #d8c8b3; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { margin: 0 0 6px; }
.site-footer a { color: #f1e3cb; }
.site-footer a:hover { color: #fff; }
.site-footer .legal {
  border-top: 1px solid #4a3a2c;
  padding-top: 24px;
  font-size: 13px;
  color: #a08e76;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

/* Mobile nav */
@media (max-width: 760px) {
  .nav-toggle { display: inline-flex; }
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-line);
    padding: 8px 16px 16px;
    gap: 0;
    box-shadow: var(--shadow-md);
  }
  .nav.open { display: flex; }
  .nav a {
    padding: 12px 14px;
    border-radius: 8px;
  }
  .site-header .container { position: relative; }
}