/* parallengine.com -- grainy-textured / immersive-scroll / aurora-gradient / shake-error */
/* Headlines & body use "Inter" (Google Fonts), neo-grotesque with engineering precision */

* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --engine-dark: #0A0820;
  --aurora-green: #28C860;
  --aurora-purple: #6840B0;
  --aurora-amber: #D8A030;
  --error-red: #E04850;
  --city-steel: #384058;
  --paper: #E8E8F0;
  --line-h: 1.75;
}

html, body {
  width: 100%;
  background: var(--engine-dark);
  color: var(--paper);
  font-family: "Inter", system-ui, sans-serif;
  font-weight: 400;
  font-size: clamp(15px, 1vw, 17px);
  line-height: var(--line-h);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

body {
  position: relative;
  min-height: 100vh;
}

/* Grain layer (full-page, scroll-intensifying) */
.grain-svg {
  position: fixed;
  inset: 0;
  width: 0;
  height: 0;
  pointer-events: none;
}

.grain-layer {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 5;
  opacity: 0.05;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='220' height='220'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0.92  0 0 0 0 0.92  0 0 0 0 0.94  0 0 0 1 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)'/></svg>");
  background-size: 220px 220px;
  mix-blend-mode: overlay;
  transition: opacity 400ms linear;
}

/* Aurora gradient backdrop (scroll-intensifying) */
.aurora-bg {
  position: fixed;
  inset: 0;
  z-index: 1;
  background:
    radial-gradient(60vw 80vh at 20% 20%, rgba(40, 200, 96, 0.18), transparent 60%),
    radial-gradient(70vw 90vh at 80% 60%, rgba(104, 64, 176, 0.22), transparent 60%),
    radial-gradient(50vw 60vh at 50% 100%, rgba(216, 160, 48, 0.10), transparent 60%),
    var(--engine-dark);
  background-size: 200% 200%, 200% 200%, 200% 200%, auto;
  animation: aurora-shift 22s ease-in-out infinite;
  transition: filter 400ms linear;
  pointer-events: none;
}

@keyframes aurora-shift {
  0%   { background-position: 0% 0%, 100% 100%, 50% 100%, 0 0; }
  50%  { background-position: 60% 30%, 30% 70%, 70% 50%, 0 0; }
  100% { background-position: 0% 0%, 100% 100%, 50% 100%, 0 0; }
}

/* Main scroll column */
#immersive {
  position: relative;
  z-index: 10;
  width: 100%;
}

/* Shake-error keyframes (engine vibration) */
@keyframes shake-error {
  0%   { transform: translate(0, 0) rotate(0deg); }
  20%  { transform: translate(-3px, 1px) rotate(-0.5deg); }
  40%  { transform: translate(3px, -1px) rotate(0.5deg); }
  60%  { transform: translate(-2px, 2px) rotate(-0.3deg); }
  80%  { transform: translate(2px, -2px) rotate(0.3deg); }
  100% { transform: translate(0, 0) rotate(0deg); }
}

.is-shaking {
  animation: shake-error 200ms linear;
}

/* ================ Section: Engine ignition ================ */
.ignition {
  position: relative;
  min-height: 100vh;
  padding: 6vh 7vw 0 7vw;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
}

.ignition-inner {
  position: relative;
  z-index: 2;
  margin-bottom: 22vh;
  max-width: 1200px;
}

.meta-label {
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--aurora-green);
  display: inline-block;
  margin-bottom: 1.4em;
}

.domain-mark {
  font-family: 'Inter', sans-serif;
  font-weight: 800;
  font-size: clamp(28px, 7vw, 96px);
  letter-spacing: -0.02em;
  line-height: 1.02;
  color: var(--paper);
  opacity: 0;
  transform: translateX(-40px);
  animation: domain-slide 600ms cubic-bezier(0.2, 0.7, 0.2, 1) 200ms forwards;
}

@keyframes domain-slide {
  to { opacity: 1; transform: translateX(0); }
}

.ignition-tag {
  margin-top: 1.4rem;
  font-style: italic;
  font-size: 14px;
  color: rgba(232, 232, 240, 0.78);
  max-width: 56ch;
}

.ignition-readout {
  margin-top: 3rem;
  display: flex;
  flex-wrap: wrap;
  gap: 2.4rem;
}

.readout-row {
  display: inline-flex;
  align-items: baseline;
  gap: 0.6rem;
  border-left: 1px solid var(--city-steel);
  padding-left: 0.9rem;
}

.r-key {
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--aurora-amber);
}

.r-val {
  font-weight: 800;
  font-size: clamp(20px, 2.4vw, 32px);
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.city-skyline {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  width: 100%;
  height: 22vh;
  z-index: 1;
  pointer-events: none;
}

.skyline-group path {
  stroke-dasharray: 4000;
  stroke-dashoffset: 4000;
  animation: city-draw 1000ms ease-out 400ms forwards;
}

@keyframes city-draw {
  to { stroke-dashoffset: 0; }
}

/* ================ Generic layer heading ================ */
.layer-heading {
  padding: 14vh 7vw 4vh 7vw;
  max-width: 1200px;
}

.section-title {
  font-family: 'Inter', sans-serif;
  font-weight: 800;
  font-size: clamp(28px, 4.5vw, 64px);
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--paper);
  max-width: 22ch;
}

.section-title em {
  font-style: italic;
  color: var(--aurora-green);
}

/* ================ Section: Shards ================ */
.layer-shards {
  position: relative;
  padding-bottom: 8vh;
}

.shard-grid {
  padding: 0 7vw;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2px;
  border-top: 1px solid var(--city-steel);
  border-left: 1px solid var(--city-steel);
}

.shard {
  padding: 2.6rem 1.8rem;
  background: rgba(10, 8, 32, 0.55);
  border-right: 1px solid var(--city-steel);
  border-bottom: 1px solid var(--city-steel);
  position: relative;
  transition: background 400ms ease;
}

.shard:hover {
  background: rgba(40, 200, 96, 0.06);
}

.shard-num {
  font-weight: 800;
  font-size: clamp(28px, 3vw, 48px);
  color: var(--aurora-purple);
  letter-spacing: -0.02em;
  display: block;
  margin-bottom: 0.6rem;
}

.shard-h {
  font-family: 'Inter', sans-serif;
  font-weight: 800;
  font-size: clamp(18px, 1.8vw, 24px);
  letter-spacing: -0.01em;
  margin-bottom: 0.6rem;
  color: var(--paper);
}

.shard p {
  color: rgba(232, 232, 240, 0.82);
  max-width: 38ch;
}

/* ================ Section: Pipeline ================ */
.layer-pipeline { position: relative; padding-bottom: 10vh; }

.pipeline-track {
  padding: 0 7vw;
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 1.4rem;
}

.pipeline-track::before {
  content: "";
  position: absolute;
  top: 22px;
  left: calc(7vw + 28px);
  right: calc(7vw + 28px);
  height: 1px;
  background: linear-gradient(to right, var(--aurora-purple), var(--aurora-green), var(--aurora-amber));
  opacity: 0.7;
}

.stage {
  position: relative;
  padding-top: 3.6rem;
}

.stage-dot {
  position: absolute;
  top: 12px;
  left: 0;
  width: 22px;
  height: 22px;
  border: 1px solid var(--aurora-green);
  border-radius: 50%;
  background: var(--engine-dark);
  transition: background 300ms ease, transform 300ms ease;
}

.stage.is-active .stage-dot {
  background: var(--aurora-green);
  transform: scale(1.15);
}

.stage h3 {
  font-weight: 800;
  font-size: clamp(18px, 1.6vw, 22px);
  letter-spacing: -0.01em;
  margin: 0.4rem 0 0.5rem;
}

.stage p {
  color: rgba(232, 232, 240, 0.82);
  font-size: 14px;
}

/* ================ Section: Diagrams ================ */
.layer-diagrams { padding-bottom: 10vh; }

.diagram-row {
  padding: 0 7vw;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.6rem;
}

.diagram-card {
  background: rgba(10, 8, 32, 0.5);
  border: 1px solid var(--city-steel);
  padding: 1.4rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.diagram-svg {
  width: 100%;
  height: 160px;
}

.diagram-svg .d-anim {
  stroke-dasharray: 800;
  stroke-dashoffset: 800;
  transition: stroke-dashoffset 1000ms ease-out;
}

.diagram-card.is-visible .d-anim {
  stroke-dashoffset: 0;
}

.diagram-label {
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--aurora-amber);
}

/* ================ Section: Aside ================ */
.layer-aside {
  padding: 8vh 7vw 10vh;
}

.aside-block {
  max-width: 720px;
  border-left: 2px solid var(--aurora-purple);
  padding-left: 1.6rem;
}

.aside-text {
  font-style: italic;
  font-size: clamp(17px, 1.6vw, 22px);
  line-height: 1.55;
  color: rgba(232, 232, 240, 0.92);
}

.aside-text em {
  color: var(--aurora-green);
  font-style: italic;
}

/* ================ Section: Throughput ================ */
.layer-throughput { padding-bottom: 10vh; }

.throughput-grid {
  padding: 0 7vw;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.6rem;
}

.tp-cell {
  border: 1px solid var(--city-steel);
  background: rgba(10, 8, 32, 0.55);
  padding: 2rem 1.6rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.tp-num {
  font-weight: 800;
  font-size: clamp(36px, 5vw, 72px);
  letter-spacing: -0.02em;
  color: var(--aurora-green);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.tp-suffix {
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--aurora-amber);
}

/* ================ Section: Deep ================ */
.layer-deep {
  position: relative;
  padding-bottom: 14vh;
  overflow: hidden;
}

.deep-block {
  padding: 0 7vw;
  max-width: 760px;
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
}

.deep-block p {
  color: rgba(232, 232, 240, 0.88);
  font-size: clamp(15px, 1.1vw, 18px);
}

.deep-block em {
  color: var(--aurora-green);
  font-style: italic;
}

.deep-fineprint {
  color: rgba(232, 232, 240, 0.62) !important;
  font-style: italic;
  font-size: 14px !important;
}

.city-skyline-deep {
  position: relative;
  display: block;
  margin-top: 6vh;
  height: 26vh;
  opacity: 0.7;
}

/* ================ Footer ================ */
.engine-footer {
  border-top: 1px solid var(--city-steel);
  padding: 3rem 7vw;
}

.footer-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-mark {
  font-weight: 800;
  font-size: clamp(16px, 1.4vw, 22px);
  letter-spacing: -0.02em;
}

/* ================ Reveal helper ================ */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 700ms ease, transform 700ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Responsive */
@media (max-width: 760px) {
  .pipeline-track {
    grid-template-columns: 1fr;
  }
  .pipeline-track::before {
    left: calc(7vw + 11px);
    right: auto;
    top: 0;
    bottom: 0;
    width: 1px;
    height: auto;
    background: linear-gradient(to bottom, var(--aurora-purple), var(--aurora-green), var(--aurora-amber));
  }
  .stage { padding-top: 0; padding-left: 2.4rem; }
  .stage-dot { top: 0; left: 0; }
  .ignition-readout { gap: 1.2rem; }
}