:root {
  /* Typography compliance tokens: Space Mono" sparingly for serial numbers. */
  --deep: #3A0718;
  --merlot: #65132B;
  --mint: #69E6C3;
  --cream: #FFF3DE;
  --apricot: #FFB86B;
  --blue: #73D7FF;
  --charcoal: #151015;
  --heading: 'Nunito', sans-serif;
  --body: 'Atkinson Hyperlegible', sans-serif;
  --mono: 'Space Mono', monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--cream);
  font-family: var(--body);
  background: linear-gradient(180deg, var(--deep), var(--merlot) 44%, var(--deep));
  overflow-x: hidden;
}

.liquid-field {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(circle at 12% 18%, rgba(115, 215, 255, .20), transparent 12%),
    radial-gradient(circle at 72% 8%, rgba(105, 230, 195, .13), transparent 16%),
    radial-gradient(circle at 82% 72%, rgba(255, 184, 107, .12), transparent 14%);
}
.liquid-field::before, .liquid-field::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(115, 215, 255, .48) 0 2px, transparent 3px), radial-gradient(circle, rgba(255, 243, 222, .24) 0 1px, transparent 2px);
  background-size: 92px 130px, 160px 180px;
  animation: fieldRise 28s linear infinite;
}
.liquid-field::after { opacity: .35; animation-duration: 43s; }

main { position: relative; z-index: 1; }
.scene { min-height: 100vh; position: relative; padding: 6rem clamp(1rem, 4vw, 4rem); }
.chapter-sticker {
  position: sticky;
  top: 1rem;
  z-index: 5;
  width: max-content;
  padding: .65rem 1rem;
  border: 2px dashed var(--blue);
  border-radius: 999px;
  color: var(--charcoal);
  background: var(--apricot);
  font-family: var(--mono);
  font-size: .8rem;
  box-shadow: 0 12px 34px rgba(21, 16, 21, .35);
  transform: rotate(-2deg);
}
.chapter-sticker.cream { background: var(--cream); border-color: var(--merlot); }

.tank-window {
  min-height: calc(100vh - 8rem);
  border: 2px solid rgba(115, 215, 255, .38);
  border-radius: 4rem;
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, rgba(58, 7, 24, .92), rgba(101, 19, 43, .78)), radial-gradient(circle at 50% 105%, rgba(105, 230, 195, .16), transparent 34%);
  box-shadow: inset 0 0 80px rgba(115, 215, 255, .16), 0 34px 90px rgba(21, 16, 21, .45);
}
.buoy-title { position: absolute; left: clamp(1.5rem, 6vw, 6rem); bottom: 10%; width: min(720px, 82vw); }
h1, h2, h3 { font-family: var(--heading); line-height: .95; margin: 0; }
h1 { font-size: clamp(4rem, 12vw, 11rem); letter-spacing: -.08em; text-shadow: 0 12px 0 rgba(21, 16, 21, .2); animation: titleRise 1.2s ease-out both; }
.buoy-title p, .section-intro p { font-size: clamp(1.05rem, 2vw, 1.35rem); max-width: 56ch; }
.mono-tag, .score { font-family: var(--mono); letter-spacing: .06em; text-transform: uppercase; }
.mono-tag { color: var(--blue); font-size: .76rem; }
.story-link, .ripple-button {
  display: inline-block;
  margin-top: 1rem;
  border: 0;
  border-radius: 999px;
  background: var(--mint);
  color: var(--charcoal);
  padding: 1rem 1.25rem;
  font: 900 1rem var(--heading);
  text-decoration: none;
  box-shadow: 0 12px 0 var(--charcoal);
  cursor: pointer;
}

.bubble { position: absolute; border: 2px solid rgba(115, 215, 255, .55); border-radius: 50%; background: rgba(115, 215, 255, .08); animation: bubbleUp linear infinite; }
.b1 { width: 80px; height: 92px; left: 12%; bottom: -120px; animation-duration: 16s; }
.b2 { width: 34px; height: 34px; left: 43%; bottom: -80px; animation-duration: 12s; animation-delay: -4s; }
.b3 { width: 130px; height: 98px; right: 12%; bottom: -160px; animation-duration: 22s; animation-delay: -8s; }
.b4 { width: 52px; height: 76px; right: 32%; bottom: -90px; animation-duration: 17s; animation-delay: -2s; }
.b5 { width: 22px; height: 22px; left: 72%; bottom: -60px; animation-duration: 10s; animation-delay: -7s; }

.flip-card { perspective: 1200px; cursor: pointer; }
.flip-inner { position: relative; width: 100%; height: 100%; min-height: inherit; transform-style: preserve-3d; transition: transform .7s cubic-bezier(.2,.8,.2,1); }
.flip-card.is-flipped .flip-inner { transform: rotateY(180deg); }
.card-face {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  border-radius: 2rem;
  padding: 1.25rem;
  border: 2px solid rgba(21, 16, 21, .18);
  overflow: hidden;
}
.card-front { background: var(--cream); color: var(--deep); }
.card-back { background: var(--merlot); color: var(--cream); transform: rotateY(180deg); border-color: rgba(105, 230, 195, .45); }
.score { display: inline-flex; align-items: center; min-height: 2.4rem; padding: .35rem .7rem; border-radius: 999px; background: var(--blue); color: var(--charcoal); font-weight: 700; }
.score.apricot { background: var(--apricot); }
.score.mint { background: var(--mint); }

.drift-card { position: absolute; width: clamp(220px, 23vw, 340px); height: 310px; filter: drop-shadow(0 24px 28px rgba(21,16,21,.35)); }
.drift-one { top: 10%; right: 22%; animation: orbitOne 13s ease-in-out infinite; }
.drift-two { top: 31%; right: 5%; width: clamp(210px, 20vw, 300px); height: 260px; animation: orbitTwo 16s ease-in-out infinite; }
.drift-three { top: 8%; left: 8%; width: clamp(190px, 19vw, 280px); height: 280px; animation: orbitThree 15s ease-in-out infinite; }
.device-icon { width: 110px; height: 110px; margin: .6rem 0; fill: none; stroke: var(--charcoal); stroke-width: 7; stroke-linecap: round; stroke-linejoin: round; }
.current-line { height: 7px; border-radius: 99px; background: linear-gradient(90deg, transparent, var(--mint), var(--blue), transparent); animation: currentFlow 2s linear infinite; margin-top: 1rem; }

.section-intro { max-width: 900px; margin: 2rem 0 3rem; }
.section-intro h2, .cream-clearing h2 { font-size: clamp(2.8rem, 7vw, 6.6rem); letter-spacing: -.05em; }
.sorting-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  grid-auto-rows: minmax(86px, auto);
  gap: 1rem;
  background: repeating-linear-gradient(180deg, transparent 0 86px, rgba(115, 215, 255, .13) 87px 89px, transparent 90px 172px);
  border-radius: 3rem;
  padding: 1rem;
}
.review-card { min-height: 280px; transform: translateY(var(--float, 0)); transition: transform .25s ease; }
.review-card.wide { grid-column: span 7; grid-row: span 4; min-height: 410px; }
.review-card.tall { grid-column: span 3; grid-row: span 5; min-height: 520px; }
.review-card.square { grid-column: span 2; grid-row: span 3; }
.review-card.capsule { grid-column: span 6; grid-row: span 2; min-height: 230px; }
.lane-a { --float: 6px; }.lane-b { --float: -8px; }.lane-c { --float: 12px; }.lane-d { --float: -4px; }
.tech-bubble, .motif { border: 2px solid var(--blue); background: rgba(115,215,255,.18); border-radius: 999px; }
.tech-bubble { margin-top: 1.5rem; padding: 1rem; width: max-content; font-family: var(--mono); }
.mini-circuit { height: 160px; margin-top: 2rem; border-radius: 2rem; background: linear-gradient(90deg, transparent 20%, var(--mint) 21% 23%, transparent 24%), linear-gradient(var(--mint), var(--mint)); background-size: 38px 100%, 100% 3px; background-position: 0 0, 0 50%; opacity: .65; }
.glyph-row { margin-top: 2rem; font-size: 3rem; color: var(--merlot); }
.timeline { display: flex; flex-wrap: wrap; gap: .5rem; margin-top: 1rem; }
.timeline b { padding: .45rem .65rem; border-radius: 999px; background: var(--apricot); color: var(--charcoal); font-family: var(--mono); font-size: .72rem; }

.water-pane { min-height: 78vh; border-radius: 4rem 2rem 5rem 2.5rem; padding: clamp(1.5rem, 5vw, 4rem); background: linear-gradient(140deg, rgba(115,215,255,.20), rgba(105,230,195,.10)), rgba(101,19,43,.62); border: 2px solid rgba(115,215,255,.36); box-shadow: inset 0 0 70px rgba(255,243,222,.08); }
.motif-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; margin: 3rem 0; }
.motif { aspect-ratio: 1; display: grid; place-items: center; color: var(--cream); font: 900 1.4rem var(--heading); position: relative; overflow: hidden; }
.motif::before { content: ""; width: 42%; height: 58%; border: 5px solid var(--cream); border-radius: 1rem; position: absolute; opacity: .55; }
.kelp-board::before { border-radius: .6rem; transform: rotate(18deg); background: repeating-linear-gradient(90deg, transparent 0 15px, rgba(105,230,195,.7) 16px 19px); }
.bottle-cell::before { border-radius: 2rem 2rem .8rem .8rem; }
.recycle-star::before { width: 48%; height: 48%; clip-path: polygon(50% 0,61% 35%,98% 35%,68% 57%,79% 91%,50% 70%,21% 91%,32% 57%,2% 35%,39% 35%); background: var(--apricot); border: 0; }
.ripple-button.is-rippling { animation: buttonRipple .55s ease; }

.resurface { color: var(--deep); }
.cream-clearing { min-height: 82vh; border-radius: 5rem; background: var(--cream); padding: clamp(1.5rem, 5vw, 5rem); box-shadow: 0 -30px 90px rgba(255,243,222,.25); }
.cream-clearing .mono-tag { color: var(--merlot); }
.surface-cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; margin-top: 3rem; }
.surface-cards article { min-height: 210px; border-radius: 2rem; padding: 1.2rem; background: linear-gradient(180deg, rgba(105,230,195,.35), rgba(115,215,255,.18)); border: 2px dashed var(--merlot); transform: translateY(30px); opacity: 0; transition: .7s ease; }
.surface-cards article.is-visible { transform: translateY(0); opacity: 1; }
.surface-cards b { font-family: var(--mono); color: var(--merlot); }

@keyframes fieldRise { from { background-position: 0 0, 0 0; } to { background-position: 0 -900px, 0 -700px; } }
@keyframes titleRise { from { transform: translateY(70px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
@keyframes bubbleUp { from { transform: translateY(0) scale(1); } to { transform: translateY(-120vh) scale(1.2); } }
@keyframes orbitOne { 0%,100% { transform: translate(0,0) rotate(-5deg); } 50% { transform: translate(18px, -24px) rotate(4deg); } }
@keyframes orbitTwo { 0%,100% { transform: translate(0,0) rotate(7deg); } 50% { transform: translate(-28px, 18px) rotate(-3deg); } }
@keyframes orbitThree { 0%,100% { transform: translate(0,0) rotate(4deg); } 50% { transform: translate(22px, 24px) rotate(-6deg); } }
@keyframes currentFlow { from { background-position: -200px 0; } to { background-position: 200px 0; } }
@keyframes buttonRipple { 0% { box-shadow: 0 12px 0 var(--charcoal), 0 0 0 0 rgba(115,215,255,.5); } 100% { box-shadow: 0 12px 0 var(--charcoal), 0 0 0 30px rgba(115,215,255,0); } }

@media (max-width: 900px) {
  .drift-card { position: relative; top: auto; left: auto; right: auto; display: inline-block; margin: 1rem; vertical-align: top; }
  .buoy-title { position: relative; left: auto; bottom: auto; padding: 2rem; }
  .tank-window { padding-top: 1rem; }
  .review-card.wide, .review-card.tall, .review-card.square, .review-card.capsule { grid-column: span 12; min-height: 330px; }
  .motif-row, .surface-cards { grid-template-columns: 1fr; }
}