/* ═══════════════════════════════════════════════
   IceCap Thermal Energy — icecap.energy
   Design: dark navy / cyan-teal / bold white
   ═══════════════════════════════════════════════ */

/* ── TOKENS ─────────────────────────────────── */
:root {
  --brand-navy:     #27497B;
  --bg-0:           var(--brand-navy);
  --bg-1:           #213f6c;
  --bg-2:           #1c385f;
  --bg-card:        #1f3d68;
  --bg-card-hover:  #284f85;
  --bg-table-head:  #18345c;
  --bg-section-alt: #203d68;

  --accent:         #00b4d8;
  --accent-dim:     rgba(0, 180, 216, 0.12);
  --accent-border:  rgba(0, 180, 216, 0.28);
  --accent-glow:    rgba(0, 180, 216, 0.06);
  --brand-blue:     var(--brand-navy);

  --text-primary:   #ffffff;
  --text-secondary: #8fb8d0;
  --text-muted:     #4d7a93;
  --text-label:     #00b4d8;

  --border:         rgba(255, 255, 255, 0.07);
  --border-card:    rgba(0, 180, 216, 0.18);

  --nav-h:          64px;
  --max-w:          1200px;
  --r:              10px;
  --r-sm:           6px;
  --ease:           cubic-bezier(0.16, 1, 0.3, 1);
}

/* ── RESET ───────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--bg-0);
  color: var(--text-primary);
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
em { font-style: normal; color: var(--accent); }

/* ── LAYOUT ──────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 60px);
}

section {
  padding: clamp(72px, 10vw, 120px) 0;
}

/* ── TYPOGRAPHY ──────────────────────────────── */
h1, h2, h3 {
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.6rem);
  max-width: 18ch;
}

h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.75rem);
  max-width: 22ch;
  margin-bottom: 1.25rem;
}

h3 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

p { color: var(--text-secondary); }

.section-eyebrow {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.9rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-eyebrow::before {
  content: '';
  display: block;
  width: 28px;
  height: 2px;
  background: var(--accent);
  flex-shrink: 0;
}

.section-intro {
  font-size: clamp(1rem, 1.5vw, 1.15rem);
  max-width: 68ch;
  color: var(--text-secondary);
  margin-bottom: 3rem;
  line-height: 1.7;
}

/* ── BUTTONS ─────────────────────────────────── */
.btn-primary,
.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 28px;
  border-radius: var(--r-sm);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: all 0.2s var(--ease);
  cursor: pointer;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg-0);
  border: 1.5px solid var(--accent);
}

.btn-primary:hover {
  background: #22cdf0;
  border-color: #22cdf0;
  box-shadow: 0 0 24px rgba(0, 180, 216, 0.4);
}

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border: 1.5px solid rgba(255,255,255,0.25);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn-large {
  padding: 16px 36px;
  font-size: 1rem;
}

/* ─────────────────────────────────────────────
   NAV
──────────────────────────────────────────────── */
#nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 900;
  height: var(--nav-h);
  transition: background 0.3s, border-color 0.3s, backdrop-filter 0.3s;
}

#nav.scrolled {
  background: rgba(39, 73, 123, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 60px);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo { display: flex; align-items: center; }
.nav-logo img { height: 38px; width: auto; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s;
}

.nav-links a:hover { color: var(--text-primary); }

.nav-cta {
  padding: 8px 20px;
  border: 1.5px solid var(--accent-border);
  border-radius: var(--r-sm);
  color: var(--accent) !important;
  transition: all 0.2s !important;
}

.nav-cta:hover {
  background: var(--accent-dim);
  border-color: var(--accent) !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  width: 36px;
  height: 36px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s var(--ease);
  transform-origin: center;
}

.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─────────────────────────────────────────────
   HERO
──────────────────────────────────────────────── */
#hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  padding: 0;
  overflow: hidden;
}

.hero-bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(rgba(0, 180, 216, 0.07) 1px, transparent 1px);
  background-size: 32px 32px;
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  top: -20%;
  left: 50%;
  transform: translateX(-50%);
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(0, 180, 216, 0.09) 0%, transparent 65%);
  pointer-events: none;
}

.hero-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: calc(var(--nav-h) + 60px);
  padding-bottom: 80px;
  position: relative;
  z-index: 1;
}

.hero-logo-wrap {
  margin-bottom: 2.5rem;
}

.hero-logo {
  height: clamp(40px, 6vw, 64px);
  width: auto;
}

#hero h1 {
  max-width: 920px;
  margin-bottom: 1.25rem;
  color: var(--text-primary);
}

.hero-subhead {
  font-size: clamp(1.05rem, 1.8vw, 1.3rem);
  color: var(--text-secondary);
  max-width: 80ch;
  margin-bottom: 2rem;
  font-weight: 400;
  line-height: 1.6;
}

.hero-tagline {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.45rem;
  width: 100%;
  max-width: 920px;
  margin: 0 0 2rem;
  padding: 0;
  text-align: center;
}

.tagline-label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
}

.tagline-text {
  font-family: 'IBM Plex Mono', monospace;
  font-size: clamp(2rem, 2.7vw, 2.45rem);
  line-height: 1.12;
  color: var(--text-primary);
  font-weight: 600;
}

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

.hero-scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--text-muted);
  transition: color 0.2s;
  z-index: 1;
}

.hero-scroll-hint:hover { color: var(--accent); }

.scroll-dot {
  animation: scrollBounce 2s ease-in-out infinite;
}

@keyframes scrollBounce {
  0%, 100% { cy: 9; }
  50% { cy: 14; }
}

/* ─────────────────────────────────────────────
   PROBLEM
──────────────────────────────────────────────── */
#problem {
  background: var(--bg-section-alt);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: clamp(56px, 7vw, 88px) 0;
}

#problem h2 {
  max-width: 920px;
}

#problem .section-intro {
  max-width: 80ch;
  margin-bottom: 2.25rem;
}

.problem-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 0.5rem;
}

.problem-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--r);
  padding: 2rem;
  transition: border-color 0.25s, transform 0.25s var(--ease);
}

.problem-card:hover {
  border-color: rgba(0, 180, 216, 0.45);
  transform: translateY(-3px);
}

.problem-icon {
  width: 44px;
  height: 44px;
  color: var(--accent);
  margin-bottom: 1.25rem;
}

.problem-icon svg { width: 100%; height: 100%; }

.problem-card h3 {
  margin-bottom: 0.65rem;
  color: var(--text-primary);
}

.problem-card p {
  font-size: 0.925rem;
  line-height: 1.7;
}

/* ─────────────────────────────────────────────
   HOW IT WORKS
──────────────────────────────────────────────── */
#how-it-works {
  background: var(--bg-0);
}

.process-steps {
  display: flex;
  align-items: flex-start;
  gap: 0;
  margin: 3rem 0 4rem;
  position: relative;
}

.step {
  flex: 1;
  padding: 0 1.5rem;
}

.step:first-child { padding-left: 0; }
.step:last-child  { padding-right: 0; }

.step h3 {
  color: var(--text-primary);
  margin-bottom: 0.65rem;
  font-size: 1rem;
}

.step p {
  font-size: 0.9rem;
  line-height: 1.7;
}

.step-arrow {
  flex-shrink: 0;
  color: var(--accent);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 1.35rem;
  line-height: 1;
  align-self: flex-start;
  margin-top: 0.05rem;
  padding: 0 0.15rem;
}

/* Diagram */
.diagram-block {
  border: 1px solid var(--border-card);
  border-radius: var(--r);
  overflow: hidden;
  background: var(--bg-card);
}

.diagram-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-table-head);
}

.diagram-label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.05em;
}

.diagram-note {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-style: italic;
}

.load-chart {
  padding: clamp(20px, 3vw, 34px);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.035), rgba(255,255,255,0)),
    var(--bg-2);
}

.chart-panels {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(16px, 2.5vw, 28px);
}

.chart-panel {
  min-width: 0;
  background: rgba(9, 23, 42, 0.34);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--r-sm);
  padding: 16px;
}

.chart-panel h3 {
  color: var(--text-primary);
  font-size: 0.95rem;
  margin-bottom: 10px;
}

.demand-chart-svg {
  width: 100%;
  height: auto;
  display: block;
  overflow: visible;
}

.chart-grid line {
  stroke: rgba(255,255,255,0.12);
  stroke-width: 1;
}

.chart-axis path {
  stroke: rgba(255,255,255,0.34);
  stroke-width: 1.2;
  fill: none;
}

.chart-axis text,
.chart-y-title {
  fill: var(--text-muted);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 10px;
}

.chart-area {
  stroke: none;
}

.demand-area {
  fill: url(#demandFillA);
}

.flattened-area {
  fill: url(#demandFillB);
}

.discharge-area {
  fill: url(#icecapFill);
}

.chart-line {
  fill: none;
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.demand-line {
  stroke: var(--accent);
}

.flattened-line {
  stroke: rgba(255,255,255,0.76);
}

.shifted-load-area {
  fill: url(#icecapFill); /* Apply the gradient fill defined in SVG */
  transform-origin: 50% 100%; /* Scale from the bottom center of the element's bounding box */
  transform-box: fill-box; /* Use the bounding box of the fill as reference for transform-origin (modern browsers) */
  transform: scaleY(0); /* Start invisible and scaled down to zero height */
  opacity: 0; /* Start fully transparent */
  animation: charge-fill 1.5s ease-out forwards; /* Animate over 1.5 seconds, keep final state */
  /* You can add an animation-delay here if you want it to start after a certain time, e.g., animation-delay: 1s; */
}

@keyframes charge-fill {
  0% {
    transform: scaleY(0);
    opacity: 0;
  }
  100% {
    transform: scaleY(1);
    opacity: 1;
  }
}

.chart-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin-top: 16px;
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.chart-legend span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.chart-legend i {
  display: block;
  width: 18px;
  height: 10px;
  border-radius: 2px;
}

.legend-demand {
  background: rgba(255,255,255,0.28);
  border: 1px solid rgba(255,255,255,0.44);
}

.legend-shifted {
  background: linear-gradient(180deg, rgba(47, 225, 255, 0.58), rgba(0, 180, 216, 0.16));
  border: 1px solid rgba(47, 225, 255, 0.72);
}

.load-chart .diagram-note {
  display: block;
  margin-top: 12px;
}

.diagram-footer-tagline {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
  color: var(--accent);
  text-align: center;
  padding: 14px 20px;
  border-top: 1px solid var(--border);
  background: var(--bg-table-head);
}

/* ─────────────────────────────────────────────
   NATURAL REFRIGERANT
──────────────────────────────────────────────── */
#refrigerant {
  background:
    linear-gradient(135deg, rgba(47, 225, 255, 0.12), rgba(255,255,255,0.02) 36%, rgba(0,0,0,0.08)),
    var(--bg-0);
  border-bottom: 1px solid var(--border);
}

.refrigerant-panel {
  border: 1px solid rgba(47, 225, 255, 0.28);
  border-radius: var(--r);
  background:
    linear-gradient(135deg, rgba(255,255,255,0.08), rgba(255,255,255,0.025)),
    var(--bg-card);
  padding: clamp(28px, 5vw, 56px);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.22);
}

.refrigerant-copy {
  max-width: 800px;
}

.refrigerant-copy h2 {
  max-width: 18ch;
}

.refrigerant-copy .section-intro {
  margin-bottom: 2.5rem;
}

.refrigerant-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.refrigerant-card {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--r-sm);
  padding: 1.35rem;
}

.refrigerant-card h3 {
  color: var(--text-primary);
  margin-bottom: 0.6rem;
}

.refrigerant-card p {
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ─────────────────────────────────────────────
   ADVANTAGES
──────────────────────────────────────────────── */
#advantages {
  background: var(--bg-section-alt);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

#advantages h2 { margin-bottom: 2.5rem; }

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.adv-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--r);
  padding: 1.75rem;
  position: relative;
  transition: border-color 0.25s, transform 0.25s var(--ease), box-shadow 0.25s;
  overflow: hidden;
}

.adv-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), transparent);
  opacity: 0;
  transition: opacity 0.25s;
}

.adv-card:hover {
  border-color: rgba(0, 180, 216, 0.4);
  transform: translateY(-3px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.adv-card:hover::before { opacity: 1; }

.adv-num {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 0.9rem;
  display: inline-block;
  padding: 3px 8px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: 3px;
}

.adv-card h3 {
  color: var(--text-primary);
  margin-bottom: 0.6rem;
  font-size: 1rem;
}

.adv-card p {
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ─────────────────────────────────────────────
   COMPARISON TABLE
──────────────────────────────────────────────── */
#comparison {
  background: var(--bg-0);
}

.table-scroll {
  overflow-x: auto;
  margin-top: 2rem;
  border-radius: var(--r);
  border: 1px solid var(--border-card);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.925rem;
  min-width: 600px;
}

.compare-table th,
.compare-table td {
  padding: 14px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.compare-table thead tr {
  background: var(--bg-table-head);
}

.compare-table th {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  vertical-align: bottom;
  line-height: 1.4;
  white-space: nowrap;
}

.compare-table th .th-sub {
  display: block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.68rem;
  font-weight: 400;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin-top: 3px;
  white-space: normal;
}

.compare-table td:first-child {
  color: var(--text-secondary);
  font-weight: 500;
  white-space: nowrap;
}

.compare-table tbody tr:last-child td { border-bottom: none; }

.compare-table tbody tr {
  background: var(--bg-card);
  transition: background 0.15s;
}

.compare-table tbody tr:nth-child(even) {
  background: var(--bg-2);
}

.compare-table tbody tr:hover {
  background: var(--bg-card-hover);
}

.col-icecap {
  background: rgba(0, 180, 216, 0.07) !important;
  border-left: 2px solid var(--accent-border) !important;
  border-right: 2px solid var(--accent-border) !important;
}

.compare-table thead .col-icecap {
  color: var(--accent) !important;
  border-top: 2px solid var(--accent) !important;
}

.col-win {
  color: var(--text-primary) !important;
  font-weight: 600;
}

.compare-tagline {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--accent);
  margin-top: 1.5rem;
  text-align: center;
}

/* ─────────────────────────────────────────────
   APPLICATIONS
──────────────────────────────────────────────── */
#applications {
  background: var(--bg-section-alt);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.apps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 2.5rem;
}

.app-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--r);
  padding: 1.75rem;
  transition: border-color 0.25s, transform 0.25s var(--ease);
}

.app-card:hover {
  border-color: rgba(0, 180, 216, 0.4);
  transform: translateY(-3px);
}

.app-icon {
  width: 48px;
  height: 48px;
  color: var(--accent);
  margin-bottom: 1.1rem;
}

.app-icon svg { width: 100%; height: 100%; }

.app-card h3 {
  font-size: 1rem;
  color: var(--text-primary);
  margin-bottom: 0.6rem;
}

.app-card p {
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ─────────────────────────────────────────────
   CONTACT
──────────────────────────────────────────────── */
#contact {
  background: var(--bg-0);
  position: relative;
  overflow: hidden;
}

.contact-wrap {
  position: relative;
  z-index: 1;
}

.contact-hex-bg {
  position: absolute;
  right: -200px;
  top: 50%;
  transform: translateY(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 180, 216, 0.05) 0%, transparent 70%);
  pointer-events: none;
}

.contact-content {
  max-width: 680px;
}

.contact-body {
  font-size: clamp(1rem, 1.4vw, 1.1rem);
  line-height: 1.7;
  max-width: 58ch;
  margin-bottom: 1.75rem;
}

.contact-bullets {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  margin-bottom: 2rem;
}

.contact-bullet {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.contact-bullet svg { color: var(--accent); flex-shrink: 0; }

.contact-tagline {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--accent);
  margin-top: 1.75rem;
}

/* ─────────────────────────────────────────────
   FOOTER
──────────────────────────────────────────────── */
#footer {
  background: var(--bg-table-head);
  border-top: 1px solid var(--border);
  padding: 48px 0;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 2rem;
  align-items: start;
}

.footer-logo { height: 28px; width: auto; }

.footer-tagline-small {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 8px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: center;
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color 0.2s;
}

.footer-links a:hover { color: var(--accent); }

.footer-legal {
  text-align: right;
}

.footer-legal p {
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--text-muted);
}

.footer-legal p + p { margin-top: 6px; }

/* ─────────────────────────────────────────────
   RESPONSIVE
──────────────────────────────────────────────── */
@media (max-width: 900px) {
  .process-steps {
    flex-direction: column;
    gap: 1.5rem;
  }

  .step {
    padding: 1.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--r);
  }

  .step:first-child,
  .step:last-child { padding: 1.5rem; }

  .step-arrow {
    display: none;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer-links {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
  }

  .footer-legal { text-align: center; }
}

@media (max-width: 768px) {
  .nav-toggle { display: flex; }

  .nav-links {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    background: rgba(39, 73, 123, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 24px 0;
    gap: 0;
    border-bottom: 1px solid var(--border);
    transform: translateY(-110%);
    opacity: 0;
    transition: transform 0.35s var(--ease), opacity 0.25s;
    pointer-events: none;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-links li { width: 100%; }

  .nav-links a {
    display: block;
    padding: 14px clamp(20px, 4vw, 60px);
    font-size: 1rem;
    border-bottom: 1px solid var(--border);
    color: var(--text-primary);
  }

  .nav-links li:last-child a { border-bottom: none; }

  .nav-cta {
    border: none !important;
    padding: 14px clamp(20px, 4vw, 60px) !important;
    border-radius: 0 !important;
    color: var(--accent) !important;
  }

  .hero-tagline {
    max-width: 100%;
  }

  .tagline-label {
    width: auto;
  }

  .problem-grid {
    grid-template-columns: 1fr;
  }

  .advantages-grid {
    grid-template-columns: 1fr;
  }

  .apps-grid {
    grid-template-columns: 1fr 1fr;
  }

  .chart-panels,
  .refrigerant-grid {
    grid-template-columns: 1fr;
  }

  .diagram-header {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 520px) {
  .nav-logo img {
    height: 34px;
  }

  .tagline-text {
    font-size: clamp(1.6rem, 7vw, 2rem);
  }

  .apps-grid {
    grid-template-columns: 1fr;
  }

  .hero-ctas {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero-ctas .btn-primary,
  .hero-ctas .btn-outline {
    width: 100%;
    justify-content: center;
  }
}