:root {
  --ink: #17131d;
  --text: #302d3a;
  --muted: #6c6578;
  --paper: #fffdfa;
  --surface: #ffffff;
  --wash: #f6f0ff;
  --violet: #49349e;
  --violet-soft: #ebe5ff;
  --pink: #f449a6;
  --pink-soft: #ffe6f2;
  --mint: #92f1bf;
  --blue: #cfe8ff;
  --amber: #f1b94b;
  --line: rgba(73, 52, 158, 0.18);
  --shadow: 0 24px 80px rgba(38, 29, 92, 0.11);
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", "SF Pro Text", "SF Pro Display", "PingFang SC", "Microsoft YaHei", Inter, "DM Sans", system-ui, sans-serif;
  --font-display: var(--font-body);
  --max: 1180px;
  --progress: 0;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(90deg, rgba(246, 240, 255, 0.72) 0 1px, transparent 1px 100px),
    linear-gradient(180deg, #fff9fd 0%, var(--paper) 46%, #f8fbff 100%);
  font-family: var(--font-body);
  line-height: 1.5;
}

img,
video {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

p,
h1,
h2,
h3,
figure {
  margin: 0;
}

p {
  color: var(--muted);
}

a:focus-visible,
video:focus-visible {
  outline: 3px solid var(--pink);
  outline-offset: 4px;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
  width: calc(var(--progress) * 100%);
  height: 4px;
  background: linear-gradient(90deg, var(--pink), var(--violet), var(--mint));
}

.skip-link {
  position: fixed;
  left: 18px;
  top: 18px;
  z-index: 101;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--ink);
  color: white;
  font-weight: 850;
  transform: translateY(-150%);
  transition: transform 160ms ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.cover {
  min-height: 100vh;
  padding: clamp(52px, 8vh, 88px) clamp(18px, 4vw, 56px) 42px;
  display: grid;
  grid-template-rows: 1fr auto;
  overflow: hidden;
}

.cover-grid,
.cover-footer,
.chapter {
  width: min(var(--max), calc(100% - 40px));
  margin-inline: auto;
}

.cover-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.96fr) minmax(320px, 0.74fr);
  gap: clamp(44px, 8vw, 112px);
  align-items: center;
}

.title-block {
  position: relative;
}

.title-block::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 9px;
  width: 8px;
  height: min(78%, 520px);
  border-radius: 999px;
  background: linear-gradient(180deg, var(--pink), var(--violet), var(--mint));
}

h1 {
  max-width: 790px;
  color: var(--violet);
  font-family: var(--font-display);
  font-size: clamp(50px, 6.6vw, 94px);
  line-height: 0.98;
  letter-spacing: 0.012em;
}

h1 span {
  color: var(--pink);
}

h2 {
  max-width: 980px;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: clamp(32px, 4.8vw, 62px);
  line-height: 1.02;
  letter-spacing: 0;
}

h3 {
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 22px;
  line-height: 1.12;
}

p,
a,
span,
strong,
b,
div,
button {
  font-family: var(--font-body);
}

.abstract,
.large-copy {
  max-width: 740px;
  color: var(--text);
  font-size: clamp(18px, 1.8vw, 22px);
}

.abstract {
  margin-top: 28px;
}

.video-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 60px;
  padding: 16px 28px;
  border-radius: 999px;
  background: var(--pink);
  color: white;
  font-size: 17px;
  font-weight: 950;
  box-shadow: 0 20px 54px rgba(244, 73, 166, 0.3);
  transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease;
}

.video-cta::before {
  content: "";
  width: 0;
  height: 0;
  margin-right: 10px;
  border-top: 7px solid transparent;
  border-bottom: 7px solid transparent;
  border-left: 11px solid white;
}

.video-cta:hover {
  background: #df328f;
  box-shadow: 0 24px 64px rgba(244, 73, 166, 0.38);
  transform: translateY(-2px);
}

.specimen {
  justify-self: end;
  width: min(100%, 430px);
}

.video-panel {
  position: relative;
  padding: clamp(28px, 4vw, 42px);
  border: 1px solid var(--line);
  border-radius: 18px;
  background:
    linear-gradient(145deg, rgba(255, 230, 242, 0.9), rgba(235, 229, 255, 0.92) 58%, rgba(207, 232, 255, 0.88)),
    white;
  box-shadow: var(--shadow);
}

.video-panel::before {
  content: "";
  display: block;
  width: 52px;
  height: 52px;
  margin-bottom: 24px;
  border-radius: 999px;
  background: var(--pink);
  box-shadow: 0 14px 34px rgba(244, 73, 166, 0.28);
}

.video-panel::after {
  content: "";
  position: absolute;
  left: calc(clamp(28px, 4vw, 42px) + 22px);
  top: calc(clamp(28px, 4vw, 42px) + 17px);
  width: 0;
  height: 0;
  border-top: 9px solid transparent;
  border-bottom: 9px solid transparent;
  border-left: 14px solid white;
}

.video-panel span {
  color: var(--pink);
  font-size: 12px;
  font-weight: 950;
  text-transform: uppercase;
}

.video-panel strong {
  display: block;
  margin-top: 10px;
  color: var(--ink);
  font-size: clamp(30px, 3.4vw, 44px);
  line-height: 1.02;
}

.video-panel p {
  margin-top: 16px;
  color: var(--text);
  font-size: 17px;
  font-weight: 720;
}

.video-panel .video-cta {
  margin-top: 30px;
  width: min(100%, 280px);
}

.cover-footer {
  margin-top: clamp(44px, 7vh, 72px);
  display: grid;
  grid-template-columns: 0.8fr 0.65fr 1.1fr 1.25fr;
  border-top: 1px solid var(--line);
}

.cover-footer div {
  padding: 16px 18px 0;
  color: var(--text);
  border-left: 1px solid var(--line);
  font-weight: 760;
}

.cover-footer div:first-child {
  border-left: 0;
}

.cover-footer span {
  display: block;
  margin-bottom: 5px;
  color: var(--pink);
  font-size: 12px;
  font-weight: 950;
  text-transform: uppercase;
}

.chapter {
  padding: clamp(82px, 10vw, 142px) 0;
}

.chapter-title {
  margin-bottom: 34px;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: start;
}

.problem .chapter-title {
  margin-bottom: 28px;
}

.problem .chapter-title h2 {
  max-width: 1080px;
}

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

.problem-layout .tension-board {
  max-width: 980px;
}

.tension-board {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.tension,
.bridge,
.research-criteria article,
.matrix,
.result-panel,
.evidence-grid figure,
.tool-stack article,
.pipeline-strip,
.demo video {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: var(--shadow);
}

.tension {
  min-height: 212px;
  padding: 24px;
}

.tension span {
  color: var(--violet);
  font-weight: 950;
  text-transform: uppercase;
}

.tension b {
  display: block;
  margin: 14px 0 12px;
  font-size: 30px;
  line-height: 1;
}

.tension.manual {
  background: linear-gradient(180deg, white, var(--violet-soft));
}

.tension.ai {
  background: linear-gradient(180deg, white, var(--pink-soft));
}

.bridge {
  grid-column: 1 / -1;
  position: relative;
  padding: 26px 28px 28px 88px;
}

.bridge span {
  position: absolute;
  left: 28px;
  top: 28px;
  width: 34px;
  height: 34px;
  border: 5px solid var(--pink);
  border-radius: 999px;
}

.bridge strong {
  color: var(--violet);
  font-size: 13px;
  text-transform: uppercase;
}

.bridge p {
  margin-top: 8px;
  color: var(--text);
  font-size: 21px;
  font-weight: 820;
}

.storyboard {
  max-width: none;
  width: 100%;
  padding-inline: max(20px, calc((100vw - var(--max)) / 2));
  background: linear-gradient(180deg, transparent, rgba(235, 229, 255, 0.72), transparent);
}

.storyboard-grid {
  display: grid;
  gap: 24px;
}

.story-card {
  display: grid;
  gap: 10px;
}

.story-card h3 {
  color: var(--ink);
  font-size: 22px;
  font-weight: 950;
  text-transform: uppercase;
}

.story-card img {
  width: 100%;
  height: auto;
  border-radius: 10px;
  box-shadow: var(--shadow);
}

.tooling {
  max-width: none;
  width: 100%;
  padding-inline: max(20px, calc((100vw - var(--max)) / 2));
}

.tooling .chapter-title {
  max-width: 760px;
  margin-bottom: 28px;
}

.tooling .chapter-title h2 {
  max-width: 760px;
  font-size: clamp(32px, 3.5vw, 46px);
  line-height: 1.06;
}

.tooling-layout {
  display: grid;
  grid-template-columns: minmax(520px, 1fr) minmax(320px, 0.82fr);
  gap: 22px clamp(24px, 4vw, 56px);
  align-items: start;
}

.tooling-copy {
  display: contents;
}

.tooling-copy .large-copy {
  grid-column: 1 / 2;
  grid-row: 2;
  margin-top: 0;
  font-size: clamp(21px, 1.9vw, 27px);
  line-height: 1.24;
}

.tooling-copy p + p {
  grid-column: 2 / 3;
  grid-row: 2;
  margin-top: 0;
  max-width: none;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
  color: var(--text);
  font-size: clamp(19px, 1.65vw, 23px);
  font-weight: 720;
  line-height: 1.28;
  box-shadow: none;
}

.tooling-visual {
  grid-column: 1 / 2;
  grid-row: 1;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.tooling-visual img {
  width: 100%;
  height: auto;
}

.tool-stack {
  grid-column: 2 / 3;
  grid-row: 1;
  display: grid;
  grid-template-rows: repeat(3, 1fr);
  gap: 8px;
  height: 100%;
}

.tool-stack article {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 12px;
  align-items: center;
  min-height: 0;
  padding: 12px 14px;
}

.tool-stack img,
.model-mark {
  width: 48px;
  height: 48px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: white;
  object-fit: contain;
  padding: 13px;
}

.model-mark {
  display: grid;
  place-items: center;
  background: var(--ink);
  color: var(--mint);
  font-size: 18px;
  font-weight: 950;
}

.tool-stack span,
.pipeline-strip span {
  color: var(--pink);
  font-size: 12px;
  font-weight: 950;
  text-transform: uppercase;
}

.tool-stack h3 {
  margin-top: 2px;
  font-size: 20px;
}

.tool-stack p {
  margin-top: 4px;
  color: var(--text);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.25;
}

.pipeline-strip {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  overflow: hidden;
}

.pipeline-strip div {
  min-height: 176px;
  padding: 22px;
  border-left: 1px solid var(--line);
}

.pipeline-strip div:first-child {
  border-left: 0;
}

.pipeline-strip strong {
  display: block;
  margin-top: 18px;
  color: var(--ink);
  font-size: 20px;
}

.pipeline-strip p {
  margin-top: 8px;
  color: var(--text);
  font-weight: 700;
}

.system,
.findings {
  max-width: none;
  width: 100%;
  padding-inline: max(20px, calc((100vw - var(--max)) / 2));
}

.system {
  background: linear-gradient(180deg, transparent, rgba(207, 232, 255, 0.58), transparent);
}

.workflow-system {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.lane {
  position: relative;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.78);
}

.lane::after {
  content: "";
  position: absolute;
  top: 62px;
  bottom: 30px;
  left: 38px;
  width: 2px;
  background: var(--line);
}

.lane-head {
  display: inline-block;
  margin-bottom: 18px;
  color: var(--ink);
  font-weight: 950;
}

.node {
  position: relative;
  z-index: 1;
  margin-top: 12px;
  margin-left: 30px;
  padding: 15px 16px;
  border: 1px solid rgba(73, 52, 158, 0.18);
  border-radius: 8px;
  background: white;
  color: var(--text);
  font-weight: 850;
}

.node::before {
  content: "";
  position: absolute;
  left: -37px;
  top: 50%;
  width: 14px;
  height: 14px;
  border-radius: 999px;
  background: var(--violet);
  transform: translateY(-50%);
}

.node.hollow::before {
  background: white;
  border: 3px solid var(--pink);
}

.research-criteria {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.research-criteria article {
  padding: 24px;
}

.marker {
  display: block;
  width: 34px;
  height: 34px;
  margin-bottom: 18px;
  border-radius: 999px;
}

.m1 {
  background: var(--mint);
}

.m2 {
  background: var(--pink);
}

.m3 {
  background: var(--amber);
}

.research-criteria p,
.matrix div {
  margin-top: 10px;
}

.matrix {
  display: grid;
  grid-template-columns: 0.7fr 1fr 1.1fr;
  overflow: hidden;
}

.matrix div {
  min-height: 86px;
  padding: 18px;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
  color: var(--muted);
}

.matrix div:nth-child(3n + 1) {
  border-left: 0;
}

.matrix .matrix-head {
  min-height: auto;
  margin-top: 0;
  color: var(--violet);
  background: var(--violet-soft);
  font-size: 13px;
  font-weight: 950;
  text-transform: uppercase;
}

.matrix div:nth-child(-n + 3) {
  border-top: 0;
}

.findings {
  background: linear-gradient(180deg, transparent, rgba(255, 230, 242, 0.72), transparent);
}

.evidence-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(240px, 0.32fr);
  gap: 16px;
  align-items: stretch;
}

.evidence-grid figure {
  overflow: hidden;
}

.evidence-grid img {
  width: 100%;
  height: auto;
}

.result-panel {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 14px;
  padding: 28px 24px;
  background: linear-gradient(180deg, white, var(--blue));
}

.metric {
  display: block;
  color: var(--pink);
  font-size: clamp(50px, 5.4vw, 68px);
  font-weight: 950;
  line-height: 0.95;
}

.metric.small {
  margin-top: auto;
  color: var(--violet);
  font-size: clamp(42px, 4.4vw, 56px);
}

.result-panel p {
  max-width: 24ch;
  color: var(--text);
  font-size: 16px;
  font-weight: 820;
  line-height: 1.35;
}

.demo {
  display: grid;
  grid-template-columns: 0.38fr 0.62fr;
  gap: clamp(28px, 5vw, 70px);
  align-items: center;
}

.demo h2 {
  margin-bottom: 16px;
}

.demo video {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #111;
}

@media (max-width: 920px) {
  .cover {
    min-height: auto;
  }

  .cover-grid,
  .split,
  .tooling-layout,
  .pipeline-strip,
  .workflow-system,
  .research-criteria,
  .evidence-grid,
  .demo {
    grid-template-columns: 1fr;
  }

  .title-block::before {
    left: -18px;
  }

  .specimen {
    justify-self: start;
    width: min(100%, 520px);
    transform: none;
  }

  .cover-footer {
    grid-template-columns: 1fr 1fr;
  }

  .cover-footer div:nth-child(odd) {
    border-left: 0;
  }

  .tooling-copy {
    display: block;
  }

  .tooling-copy .large-copy,
  .tooling-copy p + p,
  .tooling-visual,
  .tool-stack {
    grid-column: auto;
  }

  .tooling-copy .large-copy {
    margin-top: 20px;
  }

  .tooling-copy p + p {
    margin-top: 14px;
  }

  .pipeline-strip div,
  .pipeline-strip div:first-child {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .pipeline-strip div:first-child {
    border-top: 0;
  }

  .matrix {
    grid-template-columns: 1fr;
    gap: 14px;
    border: 0;
    overflow: visible;
    background: transparent;
    box-shadow: none;
  }

  .matrix .matrix-head {
    display: none;
  }

  .matrix div {
    min-height: auto;
    margin-top: 0;
    padding: 16px 18px;
    border: 1px solid var(--line);
    border-radius: 10px;
    background: white;
    box-shadow: 0 16px 44px rgba(63, 50, 143, 0.07);
  }

  .matrix div::before {
    content: attr(data-label);
    display: block;
    margin-bottom: 6px;
    color: var(--violet);
    font-size: 12px;
    font-weight: 950;
    text-transform: uppercase;
  }
}

@media (max-width: 560px) {
  .cover {
    padding-inline: 16px;
  }

  .cover-grid,
  .cover-footer,
  .chapter {
    width: min(100% - 28px, var(--max));
  }

  h1 {
    font-size: 45px;
  }

  h2 {
    font-size: 31px;
  }

  .video-cta {
    width: 100%;
  }

  .cover-footer {
    grid-template-columns: 1fr;
  }

  .cover-footer div {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .cover-footer div:first-child {
    border-top: 0;
  }

  .tension-board {
    grid-template-columns: 1fr;
  }

  .bridge {
    padding-left: 26px;
  }

  .bridge span {
    position: static;
    display: block;
    margin-bottom: 14px;
  }

  .tool-stack article {
    grid-template-columns: 58px minmax(0, 1fr);
    padding: 18px;
  }

  .tool-stack img,
  .model-mark {
    width: 58px;
    height: 58px;
    padding: 10px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}