.process-circuit {
  --circuit-copper: #b86635;
  --circuit-copper-light: #efb173;
  --circuit-dark: #101719;
  --circuit-dark-soft: #172124;
  --circuit-hot: #ff5b43;
  --circuit-liquid: #f4a340;
  --circuit-cold: #268fff;
  --circuit-suction: #30cee8;
  position: relative;
  overflow: hidden;
  padding: clamp(4.5rem, 8vw, 8rem) 0 clamp(4rem, 7vw, 7rem);
  color: #ffffff;
  background:
    radial-gradient(circle at 82% 14%, rgba(0, 151, 188, 0.14), transparent 28rem),
    radial-gradient(circle at 10% 88%, rgba(200, 121, 66, 0.11), transparent 25rem),
    linear-gradient(135deg, var(--circuit-dark-soft), var(--circuit-dark) 58%, #0b1113);
  isolation: isolate;
}

.process-circuit::before {
  position: absolute;
  z-index: -1;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 48px 48px;
  content: '';
  -webkit-mask-image: linear-gradient(to bottom, black, transparent 88%);
  mask-image: linear-gradient(to bottom, black, transparent 88%);
}

.process-circuit-header {
  max-width: 980px;
}

.process-circuit-eyebrow {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  margin: 0 0 1.1rem;
  color: #19c5e8;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.process-circuit-eyebrow::before {
  width: 2.6rem;
  height: 2px;
  background: linear-gradient(90deg, var(--circuit-copper), var(--circuit-copper-light));
  content: '';
}

.process-circuit h2 {
  max-width: 900px;
  margin: 0;
  color: #ffffff;
  font-size: clamp(2.4rem, 5.4vw, 5.4rem);
  font-weight: 800;
  letter-spacing: -0.045em;
  line-height: 0.98;
  text-wrap: balance;
}

.process-circuit-track {
  position: relative;
  max-width: 1440px;
  min-height: 540px;
  margin: clamp(3.5rem, 7vw, 7rem) auto 0;
}

.process-circuit-pipe {
  position: absolute;
  z-index: 0;
  inset: 0;
  width: 100%;
  height: 540px;
  overflow: visible;
}

.process-circuit-pipe-shadow,
.process-circuit-pipe-shell,
.process-circuit-pipe-state,
.process-circuit-flow {
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.process-circuit-pipe-shadow {
  filter: url('#pipe-shadow');
  stroke: rgba(0, 0, 0, 0.65);
  stroke-width: 24;
}

.process-circuit-pipe-shell {
  stroke: url('#copper-pipe');
  stroke-width: 18;
}

.process-circuit-pipe-state {
  opacity: 0.66;
  stroke: rgba(255, 226, 194, 0.72);
  stroke-width: 2;
  transform: translateY(-4px);
}

.process-circuit-flow {
  opacity: 1;
  stroke: currentColor;
  stroke-dasharray: 2 7;
  stroke-dashoffset: 0;
  stroke-width: 4;
  filter: drop-shadow(0 0 4px currentColor);
  animation: refrigerant-flow var(--flow-speed, 2.6s) linear infinite paused;
}

.process-circuit-segment--hot {
  --flow-speed: 2.4s;
  color: var(--circuit-hot);
}

.process-circuit-segment--liquid {
  --flow-speed: 2.3s;
  color: var(--circuit-liquid);
}

.process-circuit-segment--cold {
  --flow-speed: 2.2s;
  color: var(--circuit-cold);
}

.process-circuit-segment--suction {
  --flow-speed: 5.2s;
  color: var(--circuit-suction);
}

.process-circuit.is-visible .process-circuit-flow {
  animation-play-state: running;
}

.process-circuit-steps {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(1.5rem, 3vw, 4rem);
  margin: 0;
  padding: 0;
  list-style: none;
}

.process-circuit-step {
  padding-top: 36px;
}

.process-circuit-step:nth-child(even) {
  padding-top: 176px;
}

.process-circuit-node {
  position: relative;
  display: grid;
  width: 100px;
  height: 80px;
  place-items: center;
  color: var(--circuit-hot);
  filter: drop-shadow(0 12px 12px rgba(0, 0, 0, 0.45));
  transition: filter 280ms ease, transform 280ms cubic-bezier(0.4, 0, 0.2, 1);
}

.process-circuit-node--condenser {
  color: var(--circuit-liquid);
}

.process-circuit-node--metering {
  color: var(--circuit-cold);
}

.process-circuit-node--evaporator {
  color: var(--circuit-suction);
}

.process-circuit-node svg {
  width: 100%;
  height: 100%;
  overflow: visible;
  fill: none;
  stroke: #ffffff;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
}

.process-circuit-node .component-shell {
  fill: var(--circuit-dark);
  stroke: currentColor;
  stroke-width: 3;
}

.process-circuit-node--compressor .component-shell {
  stroke: var(--circuit-hot);
}

.process-circuit-step:hover .process-circuit-node {
  filter: drop-shadow(0 0 16px currentColor) drop-shadow(0 14px 14px rgba(0, 0, 0, 0.5));
  transform: translateY(-5px);
}

.process-circuit-copy {
  max-width: 280px;
  margin-top: 1.8rem;
}

.process-circuit-step:first-child .process-circuit-copy {
  max-width: 255px;
  margin-left: clamp(2.5rem, 3vw, 3.5rem);
}

.process-circuit-number {
  display: block;
  margin-bottom: 0.75rem;
  color: #19c5e8;
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.17em;
  text-transform: uppercase;
}

.process-circuit-copy h3 {
  margin: 0 0 0.75rem;
  color: #ffffff;
  font-size: clamp(1.55rem, 2.4vw, 2.15rem);
  font-weight: 800;
  letter-spacing: -0.025em;
  line-height: 1.05;
}

.process-circuit-copy p {
  margin: 0;
  color: #aebbc0;
  font-size: clamp(0.98rem, 1.2vw, 1.08rem);
  line-height: 1.65;
}

.process-circuit.is-enhanced .process-circuit-step {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 650ms ease, transform 650ms cubic-bezier(0.2, 0.7, 0.2, 1);
}

.process-circuit.is-enhanced.is-visible .process-circuit-step {
  opacity: 1;
  transform: translateY(0);
}

.process-circuit.is-visible .process-circuit-step:nth-child(2) {
  transition-delay: 120ms;
}

.process-circuit.is-visible .process-circuit-step:nth-child(3) {
  transition-delay: 240ms;
}

.process-circuit.is-visible .process-circuit-step:nth-child(4) {
  transition-delay: 360ms;
}

.process-circuit-cta {
  display: flex;
  max-width: 1440px;
  align-items: center;
  justify-content: flex-end;
  gap: 2rem;
  margin: 1.25rem auto 0;
  padding-top: 1.75rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.process-circuit-cta .btn-primary {
  flex: 0 0 auto;
  padding: 1rem 1.6rem;
}

@keyframes refrigerant-flow {
  to {
    stroke-dashoffset: -100;
  }
}

@keyframes refrigerant-flow-vertical {
  to {
    background-position-y: 32px;
  }
}

@media (max-width: 980px) {
  .process-circuit h2 {
    max-width: 760px;
  }

  .process-circuit-track {
    min-height: 0;
    margin-top: 4rem;
  }

  .process-circuit-pipe {
    display: none;
  }

  .process-circuit-steps {
    display: block;
    max-width: 760px;
  }

  .process-circuit-step,
  .process-circuit-step:nth-child(even) {
    --mobile-state: var(--circuit-hot);
    position: relative;
    display: grid;
    grid-template-columns: 100px minmax(0, 1fr);
    gap: clamp(1.5rem, 5vw, 3rem);
    padding: 0 0 4.25rem;
  }

  .process-circuit-step:nth-child(2) {
    --mobile-state: var(--circuit-liquid);
  }

  .process-circuit-step:nth-child(3) {
    --mobile-state: var(--circuit-cold);
  }

  .process-circuit-step:nth-child(4) {
    --mobile-state: var(--circuit-suction);
    padding-bottom: 3.4rem;
  }

  .process-circuit-step::before,
  .process-circuit-step::after {
    position: absolute;
    z-index: -1;
    top: 72px;
    bottom: 0;
    border-radius: 999px;
    content: '';
  }

  .process-circuit-step::before {
    left: 40px;
    width: 20px;
    background: linear-gradient(90deg, #70361e, var(--circuit-copper-light) 45%, var(--circuit-copper) 72%, #5d2918);
    box-shadow: 5px 6px 12px rgba(0, 0, 0, 0.45);
  }

  .process-circuit-step::after {
    left: 48px;
    width: 4px;
    background: repeating-linear-gradient(to bottom, var(--mobile-state) 0 7px, transparent 7px 24px);
    background-position-y: 0;
    box-shadow: 0 0 9px var(--mobile-state);
    animation: refrigerant-flow-vertical 1.8s linear infinite paused;
  }

  .process-circuit.is-visible .process-circuit-step::after {
    animation-play-state: running;
  }

  .process-circuit-copy {
    max-width: 560px;
    margin: 0;
    padding-top: 0.25rem;
  }

  .process-circuit-step:first-child .process-circuit-copy {
    max-width: 560px;
    margin-left: 0;
  }

}

@media (max-width: 600px) {
  .process-circuit {
    padding: 4rem 0 3.5rem;
  }

  .process-circuit h2 {
    font-size: clamp(2.3rem, 12vw, 3.4rem);
    line-height: 1;
  }

  .process-circuit-track {
    margin-top: 3.5rem;
  }

  .process-circuit-step,
  .process-circuit-step:nth-child(even) {
    grid-template-columns: 70px minmax(0, 1fr);
    gap: 1.2rem;
    padding-bottom: 3.75rem;
  }

  .process-circuit-step:nth-child(4) {
    padding-bottom: 3rem;
  }

  .process-circuit-step::before {
    top: 60px;
    left: 26px;
    width: 18px;
  }

  .process-circuit-step::after {
    top: 60px;
    left: 33px;
    width: 4px;
  }

  .process-circuit-node {
    width: 70px;
    height: 62px;
  }

  .process-circuit-copy {
    padding-top: 0;
  }

  .process-circuit-copy h3 {
    font-size: 1.55rem;
  }

  .process-circuit-copy p {
    font-size: 0.96rem;
    line-height: 1.55;
  }

  .process-circuit-cta {
    align-items: stretch;
    flex-direction: column;
    gap: 1.25rem;
  }

  .process-circuit-cta .btn-primary {
    justify-content: center;
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .process-circuit-flow,
  .process-circuit-step::after {
    animation: none;
  }

  .process-circuit.is-enhanced .process-circuit-step {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .process-circuit-node {
    transition: none;
  }

}