/* THE REGISTER OS — Light, Clean, Contractor-Trustworthy
   HVAC = clean air, healthy indoor environments.
   Light warm palette. Orange (heat) + Blue (cool) accents.
   Editorial serif headlines + clean sans body. Large numbers.
   Asymmetric layouts. Not a SaaS template. */

:root {
  --bg: #FAFAF7;
  --bg-2: #F5F4EF;
  --bg-3: #EFEEE8;
  --white: #FFFFFF;
  --text: #1A1A1A;
  --text-2: #3D3D3D;
  --muted: #6B6B6B;
  --faint: #999999;
  --border: #E0DDD5;
  --border-2: #D0CCC2;
  --orange: #E85D04;
  --orange-light: #FF8C42;
  --orange-bg: #FFF3E8;
  --blue: #0466C8;
  --blue-light: #3A86C8;
  --blue-bg: #EAF1FA;
  --green: #2D8A4E;
  --green-bg: #E8F5EC;
  --red: #C0392B;
  --radius: 14px;
  --radius-sm: 10px;
  --max: 1140px;
  --serif: 'Fraunces', Georgia, 'Times New Roman', serif;
  --sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: 'JetBrains Mono', 'SF Mono', monospace;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
.container { max-width: var(--max); margin: 0 auto; padding: 0 28px; }
a { color: inherit; text-decoration: none; }
em { font-style: italic; }

/* === NAV === */
#nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(250,250,247,0.92);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--max); margin: 0 auto; padding: 0 28px;
  height: 64px; display: flex; align-items: center; justify-content: space-between;
}
.nav-logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
.logo-badge {
  width: 30px; height: 30px; border-radius: 8px;
  background: var(--orange); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 16px; font-family: var(--sans);
}
.logo-badge.sm { width: 24px; height: 24px; font-size: 13px; border-radius: 6px; }
.os { color: var(--orange); font-weight: 600; font-size: 14px; }
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a { font-size: 14px; color: var(--muted); transition: color 0.2s; font-weight: 500; }
.nav-links a:hover { color: var(--text); }
.nav-cta {
  background: var(--text); color: var(--bg) !important; padding: 9px 18px;
  border-radius: var(--radius-sm); font-weight: 600; font-size: 14px;
}
.nav-cta:hover { background: var(--orange); }
.nav-burger { display: none; background: none; border: none; cursor: pointer; flex-direction: column; gap: 5px; }
.nav-burger span { width: 24px; height: 2px; background: var(--text); border-radius: 2px; }

/* === HERO === */
#hero { padding: 130px 0 90px; position: relative; overflow: hidden; }
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 70% 20%, rgba(232,93,4,0.06), transparent),
    radial-gradient(ellipse 60% 40% at 20% 80%, rgba(4,102,200,0.05), transparent);
}
.hero-layout { display: grid; grid-template-columns: 1.3fr 1fr; gap: 60px; align-items: center; position: relative; }
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; color: var(--muted); font-weight: 500;
  margin-bottom: 24px; padding: 6px 14px;
  background: var(--white); border: 1px solid var(--border); border-radius: 100px;
}
.dot { width: 7px; height: 7px; background: var(--orange); border-radius: 50%; animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity:1; } 50% { opacity:0.4; } }
.hero-title {
  font-family: var(--serif); font-size: clamp(2.2rem, 5vw, 3.6rem);
  font-weight: 600; line-height: 1.1; letter-spacing: -0.02em; margin-bottom: 24px;
}
.hero-title em { font-style: italic; font-weight: 400; color: var(--muted); }
.blue { color: var(--blue); }
.orange { color: var(--orange); }
.muted { color: var(--muted); }
.hero-sub { font-size: 1.15rem; color: var(--text-2); max-width: 540px; margin-bottom: 32px; line-height: 1.6; }
.hero-cta { display: flex; gap: 14px; margin-bottom: 20px; flex-wrap: wrap; }
.btn-primary {
  background: var(--text); color: var(--bg); padding: 15px 28px;
  border-radius: var(--radius-sm); font-weight: 600; font-size: 15px;
  border: none; cursor: pointer; transition: all 0.2s; display: inline-block;
}
.btn-primary:hover { background: var(--orange); transform: translateY(-1px); }
.btn-secondary {
  padding: 15px 28px; border-radius: var(--radius-sm); font-weight: 500; font-size: 15px;
  border: 1px solid var(--border-2); color: var(--text); background: var(--white); transition: all 0.2s;
}
.btn-secondary:hover { border-color: var(--blue); color: var(--blue); }
.btn-block { display: block; width: 100%; text-align: center; }
.btn-large { padding: 18px 32px; font-size: 17px; }
.hero-trust { font-size: 13px; color: var(--faint); display: flex; gap: 8px; align-items: center; }
.hero-trust .sep { color: var(--border-2); }

/* Hero card */
.hero-card {
  background: var(--white); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px;
  box-shadow: 0 2px 20px rgba(0,0,0,0.04);
}
.card-label { font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 12px; }
.card-big-num { font-family: var(--serif); font-size: 3.5rem; font-weight: 700; color: var(--orange); line-height: 1; margin-bottom: 12px; }
.card-desc { font-size: 14px; color: var(--text-2); margin-bottom: 20px; line-height: 1.5; }
.card-breakdown { border-top: 1px solid var(--border); padding-top: 16px; }
.break-row { display: flex; justify-content: space-between; padding: 6px 0; font-size: 14px; color: var(--muted); }
.break-row .mono { font-family: var(--mono); font-weight: 500; color: var(--text-2); }
.break-row.highlight .mono { color: var(--blue); font-weight: 600; }
.break-row.delta { border-top: 1px solid var(--border); margin-top: 6px; padding-top: 10px; }
.break-row.delta .mono { color: var(--green); font-weight: 700; font-size: 16px; }
.break-row.delta span:first-child { font-weight: 600; color: var(--text); }

/* === SECTIONS === */
section { padding: 90px 0; }
.section-head { margin-bottom: 48px; }
.section-num {
  font-family: var(--mono); font-size: 13px; color: var(--orange);
  font-weight: 600; margin-bottom: 12px;
}
.section-title {
  font-family: var(--serif); font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 600; line-height: 1.2; letter-spacing: -0.02em;
}
.section-lead { font-size: 1.1rem; color: var(--muted); max-width: 620px; margin-top: 16px; line-height: 1.6; }

/* === PROBLEM === */
#problem { background: var(--bg-2); }
.quotes-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; margin-bottom: 48px; }
.quote-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; border-left: 4px solid var(--orange);
}
.quote { font-family: var(--serif); font-size: 1.15rem; line-height: 1.4; margin-bottom: 14px; font-weight: 500; }
.quote .muted { font-size: 1rem; }
.src { font-size: 12px; color: var(--faint); font-family: var(--mono); }
.problem-stat-band {
  display: flex; align-items: stretch; gap: 0;
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden;
}
.ps-item { flex: 1; padding: 28px; text-align: center; }
.ps-num { font-family: var(--serif); font-size: 2.2rem; font-weight: 700; color: var(--orange); margin-bottom: 6px; }
.ps-label { font-size: 13px; color: var(--muted); line-height: 1.4; }
.ps-divider { width: 1px; background: var(--border); }

/* === HOW IT WORKS === */
.how-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; }
.how-item { padding: 0; }
.how-icon {
  width: 44px; height: 44px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; font-weight: 700; margin-bottom: 16px;
}
.how-icon.orange { background: var(--orange-bg); color: var(--orange); }
.how-icon.blue { background: var(--blue-bg); color: var(--blue); }
.how-item h3 { font-size: 1.2rem; margin-bottom: 10px; font-weight: 600; }
.how-item p { font-size: 15px; color: var(--muted); line-height: 1.6; }

/* === WHAT IT WON'T DO === */
#wont { background: var(--bg-2); }
.wont-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; margin-bottom: 32px; }
.wont-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; display: flex; gap: 14px; align-items: flex-start;
}
.wont-x {
  width: 28px; height: 28px; min-width: 28px; border-radius: 50%;
  background: rgba(192,57,43,0.1); color: var(--red);
  display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 14px;
}
.wont-card h4 { font-size: 1rem; margin-bottom: 6px; font-weight: 600; }
.wont-card p { font-size: 14px; color: var(--muted); line-height: 1.5; }
.wont-note {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; text-align: center;
}
.wont-note p { color: var(--muted); font-size: 15px; }
.refusal {
  display: block; margin-top: 12px; padding: 16px; background: var(--bg-3);
  border-radius: var(--radius-sm); font-family: var(--mono); font-size: 13px;
  color: var(--text); text-align: left; line-height: 1.5;
}

/* === TOOLS === */
.tools-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 20px; }
.tool-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; transition: all 0.2s;
}
.tool-card:hover { border-color: var(--orange); transform: translateY(-2px); box-shadow: 0 4px 20px rgba(0,0,0,0.06); }
.tool-tag {
  display: inline-block; font-size: 11px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.06em; padding: 4px 10px; border-radius: 100px;
  background: var(--orange-bg); color: var(--orange); margin-bottom: 14px;
}
.tool-card h3 { font-size: 1.25rem; margin-bottom: 10px; font-weight: 600; }
.tool-card p { font-size: 14px; color: var(--muted); line-height: 1.6; }

/* === CALCULATOR === */
#calc { background: var(--bg-2); }
.calculator-wrap {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 40px; max-width: 800px; margin: 0 auto;
  box-shadow: 0 2px 20px rgba(0,0,0,0.04);
}
.calc-controls { margin-bottom: 32px; }
.calc-row { margin-bottom: 24px; }
.calc-row label { display: block; font-size: 14px; font-weight: 600; color: var(--text); margin-bottom: 10px; }
.slider-group { display: flex; align-items: center; gap: 16px; }
input[type="range"] {
  flex: 1; -webkit-appearance: none; appearance: none; height: 6px;
  background: var(--bg-3); border-radius: 3px; outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none; width: 24px; height: 24px;
  background: var(--orange); border-radius: 50%; cursor: pointer; border: 3px solid var(--white);
  box-shadow: 0 2px 8px rgba(232,93,4,0.3);
}
input[type="range"]::-moz-range-thumb {
  width: 24px; height: 24px; background: var(--orange); border-radius: 50%;
  cursor: pointer; border: 3px solid var(--white);
}
.slider-val {
  min-width: 130px; text-align: right; font-family: var(--mono); font-size: 1.1rem;
  font-weight: 600; color: var(--orange);
}
.calc-results { display: flex; gap: 16px; margin-bottom: 24px; flex-wrap: wrap; }
.result-card {
  flex: 1; min-width: 150px; padding: 24px; border-radius: var(--radius); text-align: center;
}
.result-card.current { background: var(--bg-3); }
.result-card.improved { background: var(--blue-bg); }
.result-card.delta-card { background: var(--orange-bg); flex: 1.3; }
.result-label { font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 8px; }
.result-num { font-family: var(--serif); font-size: 1.8rem; font-weight: 700; color: var(--text); }
.result-num.big { font-size: 2.2rem; color: var(--orange); }
.result-sub { font-size: 13px; color: var(--muted); margin-top: 4px; font-family: var(--mono); }
.result-arrow { display: flex; align-items: center; font-size: 1.5rem; color: var(--faint); }
.calc-tiers { display: flex; gap: 12px; margin-bottom: 20px; flex-wrap: wrap; }
.tier {
  flex: 1; min-width: 120px; text-align: center; padding: 16px;
  background: var(--bg-3); border-radius: var(--radius-sm);
}
.tier-num { display: block; font-family: var(--serif); font-size: 1.3rem; font-weight: 700; color: var(--green); }
.tier-label { font-size: 12px; color: var(--muted); }
.calc-foot { text-align: center; font-size: 14px; color: var(--muted); }
.calc-foot strong { color: var(--text); }

/* === VOICES === */
.voices-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; margin-bottom: 32px; }
.voice-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; border-left: 4px solid var(--blue);
}
.voice-card p { font-size: 1rem; margin-bottom: 10px; line-height: 1.5; }
.voice-card .src { font-size: 12px; color: var(--faint); font-family: var(--mono); }
.voices-close { text-align: center; max-width: 700px; margin: 0 auto; font-size: 1.1rem; color: var(--muted); }

/* === PRICING === */
#pricing { background: var(--bg-2); }
.pricing-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 24px; max-width: 860px; margin: 0 auto; }
.price-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 36px; position: relative;
}
.price-card.founding { border-color: var(--orange); border-width: 2px; box-shadow: 0 4px 24px rgba(232,93,4,0.08); }
.price-badge {
  display: inline-block; font-size: 12px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.06em; padding: 5px 12px; border-radius: 100px;
  background: var(--orange); color: #fff; margin-bottom: 20px;
}
.price-badge.muted { background: var(--bg-3); color: var(--muted); }
.price-amount { font-family: var(--serif); font-size: 3rem; font-weight: 700; margin-bottom: 6px; }
.price-amount.muted { color: var(--faint); }
.price-cur { font-size: 1.5rem; vertical-align: super; }
.price-per { font-size: 1.1rem; color: var(--muted); font-weight: 400; }
.price-was { font-size: 14px; color: var(--muted); margin-bottom: 4px; }
.price-was.muted { color: var(--faint); }
.price-save { font-size: 14px; color: var(--green); font-weight: 600; margin-bottom: 24px; }
.price-features { list-style: none; margin-bottom: 24px; }
.price-features li { font-size: 14px; padding: 6px 0; color: var(--text-2); }
.price-coming {
  background: var(--bg-3); border-radius: var(--radius-sm); padding: 16px;
  font-size: 13px; color: var(--muted);
}
.price-coming ul { list-style: none; margin-top: 8px; }
.price-coming li { padding: 3px 0; }

/* === WAITLIST === */
.waitlist-wrap { max-width: 640px; margin: 0 auto; }
.wl-form { margin-bottom: 28px; }
.wl-row { display: flex; gap: 12px; margin-bottom: 12px; flex-wrap: wrap; }
.wl-form input, .wl-form select {
  flex: 1; min-width: 180px; padding: 14px 16px; background: var(--white);
  border: 1px solid var(--border-2); border-radius: var(--radius-sm);
  color: var(--text); font-size: 15px; font-family: var(--sans);
}
.wl-form input:focus, .wl-form select:focus { outline: none; border-color: var(--orange); }
.wl-form input::placeholder { color: var(--faint); }
.wl-note { text-align: center; font-size: 13px; color: var(--faint); margin-top: 14px; }
.seats-bar-wrap { text-align: center; }
.seats-bar { display: block; width: 100%; height: 8px; background: var(--bg-3); border-radius: 4px; margin-bottom: 10px; overflow: hidden; }
.seats-fill { display: block; height: 100%; background: var(--orange); border-radius: 4px; transition: width 0.5s; }
.seats-text { font-size: 14px; color: var(--muted); }
.seats-text strong { color: var(--orange); }

/* === FAQ === */
#faq { background: var(--bg-2); }
.faq-list { max-width: 760px; margin: 0 auto; }
.faq-item {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius-sm);
  margin-bottom: 12px; overflow: hidden;
}
.faq-item summary {
  padding: 20px 24px; font-weight: 600; font-size: 16px; cursor: pointer;
  list-style: none; display: flex; justify-content: space-between; align-items: center;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: '+'; font-size: 20px; color: var(--orange); font-weight: 400; }
.faq-item[open] summary::after { content: '−'; }
.faq-item p { padding: 0 24px 20px; font-size: 15px; color: var(--muted); line-height: 1.6; }

/* === FINAL CTA === */
#final-cta { padding: 100px 0; }
.cta-block { text-align: center; max-width: 640px; margin: 0 auto; }
.cta-title { font-family: var(--serif); font-size: clamp(2rem, 4vw, 3rem); font-weight: 600; line-height: 1.15; margin-bottom: 20px; }
.cta-sub { font-size: 1.15rem; color: var(--muted); margin-bottom: 32px; }

/* === FOOTER === */
footer { background: var(--text); padding: 60px 0 30px; color: #ccc; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-logo { display: flex; align-items: center; gap: 8px; font-size: 1.2rem; font-weight: 700; margin-bottom: 10px; color: #fff; }
.footer-brand p { font-size: 14px; color: #999; }
.footer-col h4 { font-size: 13px; text-transform: uppercase; letter-spacing: 0.06em; color: #999; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 14px; color: #ccc; margin-bottom: 8px; transition: color 0.2s; }
.footer-col a:hover { color: var(--orange-light); }
.footer-disclaimer { padding-top: 24px; border-top: 1px solid #333; }
.footer-disclaimer p { font-size: 12px; color: #777; line-height: 1.5; }

/* === RESPONSIVE === */
@media (max-width: 900px) {
  .hero-layout { grid-template-columns: 1fr; gap: 40px; }
  .pricing-grid { grid-template-columns: 1fr; }
  .problem-stat-band { flex-direction: column; }
  .ps-divider { width: 100%; height: 1px; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-burger { display: flex; }
  body.nav-open .nav-links {
    display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0;
    background: var(--bg); border-bottom: 1px solid var(--border); padding: 20px 28px; gap: 16px;
  }
  section { padding: 60px 0; }
  #hero { padding: 100px 0 60px; }
  .calc-results { flex-direction: column; }
  .result-arrow { transform: rotate(90deg); justify-content: center; }
  .calc-tiers { flex-direction: column; }
  .wl-row { flex-direction: column; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}
@media (max-width: 480px) {
  .container { padding: 0 20px; }
  .hero-title { font-size: 1.8rem; }
  .calculator-wrap { padding: 24px; }
  .card-big-num { font-size: 2.5rem; }
}