:root {
  /* Structural color — 严格黑白灰阶梯，不引入任何彩色 */
  --paper: #0a0a0a;
  --surface: #161616;
  --surface-2: #1e1e1e;
  --line: #2a2a2a;
  --dark: #000000;

  --sans: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --pixel: "Silkscreen", var(--mono);
  --pixel-tiny: "Press Start 2P", var(--mono);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-enter: cubic-bezier(0, 0, 0.2, 1);
  --ease-exit: cubic-bezier(0.4, 0, 1, 1);

  /* Ink tiers — white @ opacity on dark paper (Figma Ink/100..30) */
  --ink-100: rgba(255, 255, 255, 1);
  --ink-80: rgba(255, 255, 255, 0.8);
  --ink-65: rgba(255, 255, 255, 0.65);
  --ink-45: rgba(255, 255, 255, 0.45);
  --ink-30: rgba(255, 255, 255, 0.3);

  /* Type scale — same 8-step px scale as 点点2.0/3.0/moodie */
  --fs-h1: 38.5px;
  --fs-h2: 28.9px;
  --fs-t1: 23.1px;
  --fs-h3: 18.3px;
  --fs-body: 14.4px;
  --fs-eyebrow: 13.5px;
  --fs-nav: 11.6px;
  --fs-label: 10.6px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink-100);
  font-family: var(--sans);
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; }
figure { margin: 0; }
a { color: inherit; }
button { font: inherit; }

/* ---------- Topbar ---------- */
.topbar {
  position: fixed;
  z-index: 30;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 56px;
  padding: 0 28px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(10, 10, 10, 0.86);
  backdrop-filter: blur(16px);
}

.topbar__left { display: flex; align-items: center; gap: 12px; }

.topbar a,
.topbar span {
  color: var(--ink-100);
  font: 400 var(--fs-nav)/1.5 var(--mono);
  letter-spacing: 0.02em;
  text-decoration: none;
}

.topbar__back:hover,
.topbar__title:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.topbar__tag {
  padding: 4px 8px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink-80);
  font: 400 10.6px/1 var(--pixel-tiny);
  letter-spacing: 0;
}

/* ---------- Shell / index ---------- */
.page-shell {
  display: grid;
  grid-template-columns: 176px minmax(0, 1120px);
  gap: clamp(36px, 6vw, 96px);
  width: min(100% - 56px, 1416px);
  margin: 0 auto;
  padding-top: 56px;
}

.case-index {
  position: sticky;
  top: 96px;
  align-self: start;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-top: 74px;
}

.case-index__title {
  margin: 0 0 12px;
  color: var(--ink-45);
  font: 400 var(--fs-label)/1 var(--mono);
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.case-index a {
  position: relative;
  color: var(--ink-45);
  font: 400 var(--fs-nav)/1.5 var(--mono);
  text-decoration: none;
  transition: color 180ms var(--ease-enter);
}

.case-index a::before {
  position: absolute;
  top: 0.65em;
  left: -18px;
  width: 8px;
  height: 1px;
  background: var(--ink-100);
  content: "";
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity 180ms var(--ease-enter), transform 180ms var(--ease-enter);
}

.case-index a:hover,
.case-index a.is-active { color: var(--ink-100); }

.case-index a.is-active::before {
  opacity: 1;
  transform: none;
}

.case-main { min-width: 0; }

/* ---------- Hero ---------- */
.hero {
  padding: clamp(72px, 9vw, 124px) 0 clamp(56px, 7vw, 80px);
}

.hero__heading { max-width: 800px; }

.eyebrow,
.caption {
  margin: 0;
  color: var(--ink-65);
  font: 400 var(--fs-eyebrow)/1.4 var(--mono);
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 16px 0;
  color: var(--ink-100);
  font-family: "Alibaba PuHuiTi 3.0", var(--sans);
  font-size: var(--fs-h1);
  font-weight: 600;
  letter-spacing: -0.045em;
  line-height: 1.03;
}

.hero__dek {
  max-width: 700px;
  margin: 0;
  color: var(--ink-80);
  font-size: var(--fs-h3);
  font-weight: 400;
  letter-spacing: -0.015em;
  line-height: 1.4;
}

.project-meta {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
  margin: clamp(48px, 6vw, 72px) 0 32px;
  padding: 20px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.project-meta div { min-width: 0; }

.project-meta dt {
  margin-bottom: 8px;
  color: var(--ink-30);
  font: 400 var(--fs-label)/1 var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.project-meta dd {
  margin: 0;
  color: var(--ink-100);
  font-size: var(--fs-body);
  line-height: 1.5;
}

/* ---------- Media ---------- */
.media { margin: 0; }
.media img { width: 100%; height: auto; }

.media figcaption {
  max-width: 720px;
  margin-top: 12px;
  color: var(--ink-45);
  font-size: var(--fs-label);
  line-height: 1.6;
}

.media--hero {
  position: relative;
  overflow: hidden;
  display: grid;
  place-items: center;
  padding: clamp(24px, 4vw, 48px);
  background: #08040f; /* 从Jean真实录屏里直接取样的边缘像素值，跟hero-loop.html舞台背景色统一 */
  border: 1px solid rgba(117, 114, 207, 0.6); /* 真实App的 --accent-light，浅紫色描边，60%透明度降低扎眼感 */
}

.hero-clickzone {
  position: absolute;
  inset: 0;
  z-index: 20;
  cursor: none;
}

.hero-cursor-badge {
  position: fixed;
  top: 0;
  left: 0;
  width: 64px;
  height: 64px;
  margin: -32px 0 0 -32px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.94);
  color: #111;
  display: flex;
  align-items: center;
  justify-content: center;
  font: 600 11px/1 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  pointer-events: none;
  opacity: 0;
  transform: translate(-999px, -999px) scale(0.5);
  transition: opacity 180ms ease, transform 180ms ease;
  z-index: 100;
}

.hero-cursor-badge.is-visible { opacity: 1; }

.hero-stage {
  position: relative;
  width: 265px; /* 402 * 0.6591, 缩放后的真实可视宽度 */
  height: 576px;
}

.hero-frame {
  position: absolute;
  top: 0;
  left: 0;
  width: 402px;
  height: 874px;
  border: 0;
  border-radius: 46px;
  transform: scale(0.6591); /* 576 / 874 */
  transform-origin: top left;
  filter: drop-shadow(0 24px 48px rgba(0, 0, 0, 0.55));
  background: #000;
}

.hero__links {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 12px;
}

.hero__links a {
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.5 var(--mono);
  text-decoration: none;
}

.hero__note {
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.5 var(--mono);
}

.hero__links a:hover {
  color: var(--ink-100);
  text-decoration: underline;
  text-underline-offset: 4px;
}

@media (max-width: 720px) {
  .hero-stage { width: 166px; height: 360px; } /* 402 * 0.4119 */
  .hero-frame { transform: scale(0.4119); } /* 360 / 874 */
}

/* ---------- Three-second summary ---------- */
.summary-strip {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: 480px;
  margin: 0 0 clamp(64px, 8vw, 96px);
  padding-top: 24px;
  border-top: 1px solid var(--line);
  counter-reset: summary-index;
}

.summary-strip p {
  margin: 0;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.6;
  counter-increment: summary-index;
}

.summary-strip p::before {
  display: inline-block;
  width: 20px;
  margin-right: 8px;
  color: var(--ink-30);
  font: 400 var(--fs-label)/1 var(--mono);
  content: "0" counter(summary-index);
}

/* ---------- Opening statement ---------- */
.opening {
  max-width: 820px;
  margin: 0 0 clamp(88px, 11vw, 132px);
}

.opening p {
  margin: 0 0 16px;
  color: var(--ink-80);
  font-size: var(--fs-h3);
  font-weight: 400;
  letter-spacing: -0.015em;
  line-height: 1.55;
}

.opening p:last-child { margin-bottom: 0; }

.opening p.is-quiet {
  color: var(--ink-65);
  font-size: var(--fs-body);
  letter-spacing: 0;
  line-height: 1.8;
}

/* ---------- Sections / chapters ---------- */
.section {
  position: relative;
  padding: clamp(76px, 9vw, 112px) 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 72px;
}

.chapter-title {
  position: relative;
  max-width: 900px;
  margin-bottom: clamp(48px, 6vw, 72px);
}


.chapter-title h2 {
  position: relative;
  margin: 16px 0 0;
  color: var(--ink-100);
  font-size: var(--fs-h2);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 1.2;
}

.chapter-title__intro {
  position: relative;
  max-width: 650px;
  margin: 26px 0 0;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.75;
}

.prose { max-width: 720px; }

.prose p {
  margin: 0 0 16px;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.8;
}

.prose p:last-child { margin-bottom: 0; }

.prose strong,
p strong { color: var(--ink-100); font-weight: 600; }

.pull-quote {
  max-width: 800px;
  margin: 32px 0 0;
  color: var(--ink-100);
  font-size: var(--fs-t1);
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.45;
}

/* ---------- Evidence figures：辅助资料，原样展示，不裁切、不加框、不需要点击放大 ---------- */
.evidence__media img {
  display: block;
  width: 100%;
  height: auto;
}

.evidence figcaption {
  margin-top: 12px;
  color: var(--ink-45);
  font-size: var(--fs-label);
  line-height: 1.6;
}

.evidence figcaption span.quote {
  display: block;
  margin-top: 4px;
  color: var(--ink-65);
}


.evidence--compact {
  max-width: 50%;
  margin: clamp(40px, 5vw, 56px) auto 0;
}

.evidence--compact figcaption { text-align: center; }

@media (max-width: 720px) {
  .evidence--compact { max-width: 100%; }
}

.evidence-pair {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(24px, 4vw, 40px);
  margin-top: clamp(40px, 5vw, 56px);
}

.evidence-pair--tight { gap: 10px; }


.evidence-stack { margin-top: clamp(40px, 5vw, 56px); }
.evidence-stack .evidence + .evidence { margin-top: clamp(40px, 5vw, 56px); }
.evidence--masters { margin-top: clamp(40px, 5vw, 56px); }

/* ---------- Judgment table (02) ---------- */
.judgment-table {
  width: 100%;
  margin: 40px 0 0;
  border-collapse: collapse;
}

.judgment-table th,
.judgment-table td {
  padding: 16px 24px 16px 0;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.judgment-table th {
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.4 var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.judgment-table td {
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.7;
}

.judgment-table td:first-child {
  color: var(--ink-100);
  white-space: nowrap;
}

@media (max-width: 720px) {
  .judgment-table,
  .judgment-table thead,
  .judgment-table tbody,
  .judgment-table tr,
  .judgment-table td {
    display: block;
    width: 100%;
  }
  .judgment-table thead { display: none; }
  .judgment-table tr { padding: 20px 0; border-bottom: 1px solid var(--line); }
  .judgment-table td { padding: 4px 0; border: 0; }
  .judgment-table td:first-child { color: var(--ink-100); font: 400 var(--fs-label)/1.4 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; }
}

/* ---------- Pivot cases (03) ---------- */
.pivot-case {
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
}

.pivot-case:first-of-type {
  margin-top: 32px;
  padding-top: 0;
  border-top: 0;
}

.pivot-case__label {
  display: block;
  margin: 0 0 12px;
  color: var(--ink-100);
  font: 400 var(--fs-eyebrow)/1.4 var(--mono);
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.pivot-case h3 {
  margin: 0 0 12px;
  max-width: 640px;
  color: var(--ink-100);
  font-size: var(--fs-h3);
  font-weight: 400;
  letter-spacing: -0.015em;
  line-height: 1.4;
}

.pivot-case p {
  max-width: 720px;
  margin: 0;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.8;
}

.pivot-case__evidence {
  margin-top: 24px;
}

/* ---------- Simple assignment list (04) ---------- */
.assign-list {
  list-style: none;
  margin: 40px 0 0;
  padding: 24px 0 0;
  border-top: 1px solid var(--line);
}

.assign-list li {
  display: grid;
  grid-template-columns: 40px 1fr;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.assign-list span {
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.4 var(--mono);
}

.assign-list h3 {
  margin: -2px 0 8px;
  color: var(--ink-100);
  font-size: var(--fs-body);
  font-weight: 400;
}

.assign-list p {
  margin: 0;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.75;
}

.feedback-quotes {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.feedback-quotes li {
  margin: 0;
  padding: 24px;
  background: var(--surface);
  color: var(--ink-80);
  font-size: var(--fs-body);
  line-height: 1.7;
}

/* ---------- Claude Design showcase：左文字，右可交互动画 ---------- */
.claudedesign-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(32px, 5vw, 64px);
}

.claudedesign-row p { max-width: 420px; }

.claudedesign-frame-group {
  display: flex;
  gap: 16px;
  padding: clamp(20px, 3vw, 32px);
  background: var(--surface);
  border: 1px solid var(--line);
}

.claudedesign-frame-group__stage {
  position: relative;
  width: 265px;
  height: 576px;
}

.claudedesign-frame {
  position: absolute;
  top: 0;
  left: 0;
  width: 402px;
  height: 874px;
  border: 0;
  border-radius: 38px;
  transform: scale(0.6591); /* 576 / 874 */
  transform-origin: top left;
  background: #06061a;
}

@media (max-width: 1040px) {
  .claudedesign-row { grid-template-columns: 1fr; justify-items: center; text-align: center; }
  .claudedesign-row p { margin-left: auto; margin-right: auto; }
}

@media (max-width: 720px) {
  .claudedesign-frame-group { flex-direction: column; }
  .claudedesign-frame-group__stage { width: 166px; height: 360px; }
  .claudedesign-frame { transform: scale(0.4119); } /* 360 / 874 */
}

/* ---------- Callout (PRD governance bridge) ---------- */
.callout {
  margin: clamp(56px, 7vw, 80px) 0 0;
  padding: clamp(28px, 4vw, 40px);
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--ink-100);
}

.callout__label {
  display: block;
  margin: 0 0 16px;
  color: var(--ink-100);
  font: 400 var(--fs-label)/1.4 var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.callout h3 {
  max-width: 680px;
  margin: 0 0 16px;
  color: var(--ink-100);
  font-size: var(--fs-h3);
  font-weight: 400;
  letter-spacing: -0.015em;
  line-height: 1.4;
}

.callout p {
  max-width: 680px;
  margin: 0 0 14px;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.8;
}

.callout p:last-child { margin-bottom: 0; }

.callout code {
  padding: 2px 4px;
  color: var(--ink-100);
  font-family: var(--mono);
  font-size: 0.92em;
}

.callout ul {
  max-width: 680px;
  margin: 0 0 16px;
  padding: 0 0 0 16px;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.7;
}

.callout__evidence {
  margin-top: clamp(28px, 4vw, 40px);
}

.callout__evidence-caption {
  margin: 12px 0 0;
  color: var(--ink-45);
  font-size: var(--fs-label);
  line-height: 1.6;
}

/* ---------- Fix list (05) ---------- */
.fix-list {
  list-style: none;
  margin: 40px 0 0;
  padding: 8px 0 0;
  border-top: 1px solid var(--line);
}

.fix-list li {
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.fix-list p {
  margin: 0;
  font-size: var(--fs-body);
  line-height: 1.75;
}

.fix-list p.found { margin-bottom: 6px; color: var(--ink-80); }
.fix-list p.fixed { color: var(--ink-65); }

.fix-list span {
  display: inline-block;
  min-width: 44px;
  margin-right: 4px;
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.4 var(--mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.fix-list p.fixed span { color: var(--ink-100); }

/* ---------- Closing ---------- */
.closing-heading {
  max-width: 820px;
  margin: 16px 0 0;
  color: var(--ink-100);
  font-size: var(--fs-h2);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 1.2;
}

.closing-quote {
  max-width: 820px;
  margin: 20px 0 0;
  color: var(--ink-100);
  font-size: var(--fs-t1);
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.45;
}

.judgment-list {
  list-style: none;
  margin: clamp(40px, 5vw, 56px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.judgment-list li {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 24px;
  align-items: start;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.judgment-list span {
  color: var(--ink-100);
  font: 400 20px/1.3 var(--pixel), var(--mono);
}

.judgment-list p {
  margin: 2px 0 0;
  color: var(--ink-80);
  font-size: var(--fs-body);
  line-height: 1.7;
}

.closing-line {
  max-width: 700px;
  margin: clamp(40px, 5vw, 56px) 0 0;
  color: var(--ink-65);
  font-size: var(--fs-body);
  line-height: 1.85;
}

/* ---------- Case end nav ---------- */
.case-end-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-top: clamp(72px, 9vw, 112px);
  padding: 24px 0;
  border-top: 1px solid var(--ink-100);
}

.case-end-nav span,
.case-end-nav a {
  color: var(--ink-45);
  font: 400 var(--fs-label)/1.5 var(--mono);
  text-decoration: none;
}

.case-end-nav a:hover {
  color: var(--ink-100);
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* ---------- Reveal ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 700ms var(--ease-enter), transform 700ms var(--ease-enter);
}

[data-reveal][data-revealed] {
  opacity: 1;
  transform: none;
}

/* ---------- Responsive ---------- */
@media (max-width: 1040px) {
  .page-shell {
    display: block;
    width: min(100% - 40px, 920px);
  }

  .case-index { display: none; }

  .evidence-pair { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .topbar {
    min-height: 52px;
    padding: 0 16px;
  }

  .topbar__title { display: none; }

  .page-shell {
    width: min(100% - 32px, 620px);
    padding-top: 52px;
  }

  .hero { padding-top: 56px; }
  .hero h1 { font-size: 32px; }
  .hero__dek { font-size: 16px; }

  .project-meta {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    row-gap: 24px;
  }

  .feedback-quotes {
    grid-template-columns: 1fr;
  }

  .opening p { font-size: 16px; }

  .chapter-title__num { position: static; margin: 0 0 8px; font-size: 40px; }

  .judgment-table td:first-child { white-space: normal; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }
}