/* 拆开看 AI · 定稿系统：桦木做主系统，钴蓝做热词章节，番茄红做落地章节。一家字体 MiSans。 */
@font-face { font-family: "MiSans"; src: url("fonts/MiSans-Regular.woff2") format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "MiSans"; src: url("fonts/MiSans-Bold.woff2") format("woff2"); font-weight: 700; font-display: swap; }
@font-face { font-family: "MiSans"; src: url("fonts/MiSans-Heavy.woff2") format("woff2"); font-weight: 900; font-display: swap; }

:root {
  /* 底色：和钴蓝、番茄红凑成一组三原色的浅黄油色。卡片里的浅色块用 base-tint */
  --base: #ffe9a8;
  --base-tint: #ffe9a8;
  --cobalt: #2448e8;
  --cobalt-deep: #1c39c4;
  --tomato: #ff4a26;
  --ink: #141414;
  --ink-soft: #2a2a2a;
  --paper: #ffffff;
  --model: #2448e8;
  --data: #ffc21a;
  --tool: #ff4a26;
  --perm: #2bb673;
  --human: #ff78b8;
  --sans: "MiSans", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --gutter: clamp(20px, 5vw, 80px);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  /* 字号阶梯：只用这几档 */
  --t-sm: 0.875rem;
  --t-base: 1.0625rem;
  --t-lg: 1.25rem;
  --t-xl: clamp(1.5rem, 1.2rem + 1vw, 2rem);
  --t-2xl: clamp(2.25rem, 1.4rem + 3vw, 3.75rem);
  --t-hero: clamp(3.5rem, 1.6rem + 7vw, 7.5rem);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 72px; }
body {
  margin: 0;
  background: var(--base);
  color: var(--ink);
  font-family: var(--sans);
  font-size: var(--t-base);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
::selection { background: var(--data); color: var(--ink); }
:focus-visible { outline: 3px solid var(--ink); outline-offset: 3px; }
h1, h2, h3 { text-wrap: balance; }
p, li, dd { text-wrap: pretty; }
[hidden] { display: none !important; }
img { max-width: 100%; height: auto; display: block; }
button { font: inherit; color: inherit; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition-duration: 0.01ms !important; animation: none !important; } }

.skip { position: absolute; left: -999px; top: 8px; background: var(--ink); color: var(--paper); padding: 8px 12px; border-radius: 999px; z-index: 50; }
.skip:focus { left: 12px; }

/* 顶栏 */
.bar { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 20; display: flex; justify-content: space-between; align-items: center; padding: 16px var(--gutter); background: var(--base); }
.mark { display: flex; align-items: center; gap: 10px; font-weight: 900; font-size: var(--t-lg); color: inherit; text-decoration: none; }
.mark-grid { display: grid; grid-template-columns: repeat(2, 9px); gap: 2px; }
.mark-grid i { width: 9px; height: 9px; border-radius: 2px; }
.bar nav { display: flex; gap: 32px; font-weight: 700; }
.bar nav a { color: inherit; padding: 4px 0; text-decoration: underline 2px transparent; text-underline-offset: 6px; transition: text-decoration-color 0.3s var(--ease); }
@media (hover: hover) { .bar nav a:hover { text-decoration-color: currentColor; } }

/* 开场 */
.hero { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); align-items: center; gap: clamp(24px, 3vw, 48px); padding: clamp(24px, 6vh, 64px) var(--gutter) clamp(64px, 10vh, 120px); }
.hero h1 { margin: 0; font-size: var(--t-hero); line-height: 1; font-weight: 900; letter-spacing: -0.02em; }
.lead { margin: 28px 0 0; font-size: var(--t-lg); line-height: 1.6; max-width: 28em; }
.truths { list-style: none; margin: 32px 0 0; padding: 0; display: grid; gap: 14px; max-width: 30em; }
.truths li { display: grid; grid-template-columns: 22px 1fr; gap: 14px; align-items: start; font-weight: 700; line-height: 1.5; }
.truths i { width: 22px; height: 22px; border-radius: 4px; margin-top: 2px; }
.btn { display: inline-flex; align-items: center; margin-top: 36px; padding: 16px 30px; border-radius: 999px; background: var(--ink); color: var(--paper); font-weight: 700; text-decoration: none; transition: transform 0.16s var(--ease); }
.btn:active { transform: scale(0.97); }
.hero-art { margin: 0 calc(var(--gutter) * -0.5) 0 0; }

/* 热词链 · 钴蓝 */
.chain { position: relative; overflow: hidden; background: var(--cobalt); color: var(--paper); padding: clamp(80px, 12vh, 140px) var(--gutter); }
.chain-head { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 64px); align-items: end; max-width: 1320px; margin: 0 auto; }
.chain-head h2, .ladder-head h2 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; letter-spacing: -0.01em; }
.chain-head p, .ladder-head p { margin: 0; font-size: var(--t-lg); line-height: 1.6; }
.chain-body { position: relative; z-index: 1; display: grid; grid-template-columns: minmax(0, 300px) minmax(0, 1fr); gap: clamp(24px, 4vw, 56px); max-width: 1320px; margin: clamp(48px, 7vh, 80px) auto 0; align-items: start; }
.steps { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }
.step { all: unset; box-sizing: border-box; cursor: pointer; width: 100%; display: grid; grid-template-columns: 34px 1fr; gap: 14px; align-items: center; padding: 8px 12px; border-radius: 14px; font-weight: 700; transition: background-color 0.3s var(--ease), color 0.3s var(--ease), opacity 0.3s var(--ease); }
.step .n { width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center; font-size: var(--t-sm); border: 2px solid currentColor; }
.step[aria-selected="true"] { background: var(--paper); color: var(--ink); }
.step[aria-selected="true"] .n { background: var(--c); color: var(--cn, var(--ink)); border-color: var(--c); }
.step.later { opacity: 0.55; }
.step:focus-visible { outline: 3px solid var(--paper); outline-offset: 2px; }
@media (hover: hover) { .step:not([aria-selected="true"]):hover { background: var(--cobalt-deep); opacity: 1; } }
.sheet-wrap { display: grid; gap: 40px; }
.sheet { margin: 0; background: var(--paper); color: var(--ink); border-radius: 18px; padding: clamp(16px, 2vw, 28px); }
.sheet svg { display: block; width: 100%; height: auto; }
.word h3 { margin: 0; font-size: var(--t-2xl); line-height: 1.05; font-weight: 900; }
.word h3 span { display: block; margin-top: 10px; font-size: var(--t-base); font-weight: 400; opacity: 0.85; }
.word .one { margin: 22px 0 0; font-size: var(--t-xl); line-height: 1.4; font-weight: 700; max-width: 26em; }
.word .like { margin: 16px 0 0; font-size: var(--t-lg); line-height: 1.6; max-width: 34em; }
.word details { margin-top: 26px; max-width: 46em; }
.word summary { cursor: pointer; display: inline-flex; align-items: center; gap: 10px; font-weight: 700; padding: 10px 18px; border-radius: 999px; background: var(--cobalt-deep); list-style: none; }
.word summary::-webkit-details-marker { display: none; }
.word summary::after { content: "+"; font-size: var(--t-lg); line-height: 1; transition: transform 0.3s var(--ease); }
.word details[open] summary::after { transform: rotate(45deg); }
.word dl { margin: 20px 0 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
.word dt { font-size: var(--t-sm); font-weight: 900; }
.word dd { margin: 6px 0 0; line-height: 1.6; }
.word-row { display: grid; grid-template-columns: minmax(0, 1fr) clamp(140px, 16vw, 240px); gap: clamp(16px, 3vw, 40px); align-items: start; }
.word-prop { width: 100%; aspect-ratio: 1; margin-top: -12px; }

/* 落地 · 番茄红 */
.ladder { background: var(--tomato); color: var(--ink); padding: clamp(80px, 12vh, 140px) var(--gutter); }
.ladder-head { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 64px); align-items: end; max-width: 1320px; margin: 0 auto; }
.ladder-body { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 64px); align-items: center; max-width: 1320px; margin: clamp(32px, 5vh, 56px) auto 0; }
.ladder-art { margin: 0; }
.levels { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; margin-top: 8px; }
.lv { all: unset; box-sizing: border-box; cursor: pointer; display: grid; gap: 2px; padding: 12px 14px; border-radius: 14px; background: rgba(255, 255, 255, 0.22); font-weight: 700; line-height: 1.3; transition: background-color 0.3s var(--ease), color 0.3s var(--ease); }
.lv b { font-size: var(--t-xl); font-weight: 900; }
.lv[aria-selected="true"] { background: var(--ink); color: var(--paper); }
.lv:focus-visible { outline: 3px solid var(--ink); outline-offset: 2px; }
@media (hover: hover) { .lv:not([aria-selected="true"]):hover { background: rgba(255, 255, 255, 0.4); } }
.level h3 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; }
.level h3 span { display: block; margin-top: 10px; font-size: var(--t-base); font-weight: 700; }
.level .look { margin: 16px 0 0; font-size: var(--t-xl); line-height: 1.45; font-weight: 700; }
.level dl { margin: 26px 0 0; display: grid; gap: 20px; }
.level dt { font-size: var(--t-sm); font-weight: 900; }
.level dd { margin: 6px 0 0; line-height: 1.6; }
.level details summary { cursor: pointer; margin-top: 10px; font-weight: 700; text-decoration: underline; text-underline-offset: 4px; }
.level details p { margin: 10px 0 0; }
.ground { max-width: 1320px; margin: clamp(40px, 6vh, 72px) auto 0; font-size: var(--t-lg); font-weight: 700; line-height: 1.6; }

.foot { display: flex; justify-content: space-between; align-items: end; gap: 24px; flex-wrap: wrap; padding: 56px var(--gutter); }
.foot strong { font-size: var(--t-2xl); font-weight: 900; line-height: 1; }
.foot span { font-size: var(--t-sm); max-width: 32em; }

/* 手机 */
@media (max-width: 900px) {
  .bar nav { gap: 20px; }
  .hero { grid-template-columns: 1fr; }
  .hero-art { order: -1; margin: 0 calc(var(--gutter) * -1); }
  .chain-head, .ladder-head, .ladder-body { grid-template-columns: 1fr; }
  .chain-body { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); }
  .step { grid-template-columns: 30px 1fr; gap: 10px; padding: 8px 10px 8px 8px; line-height: 1.25; }
  .step .n { width: 30px; height: 30px; }
  .word dl { grid-template-columns: 1fr; }
  .levels { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .word-row { grid-template-columns: minmax(0, 1fr) 112px; }
}

/* 回头看：11 个零件 */
.recap { padding: clamp(80px, 12vh, 140px) var(--gutter) clamp(96px, 12vh, 140px); }
.recap-in { max-width: 1320px; margin: 0 auto; }
.recap h2 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; }
.recap > .recap-in > p { margin: 16px 0 0; font-size: var(--t-lg); max-width: 34em; }
.parts-groups { margin: clamp(32px, 5vh, 56px) 0 0; display: grid; gap: 28px; }
.parts-group { display: grid; grid-template-columns: minmax(0, 260px) minmax(0, 1fr); gap: 24px; align-items: center; }
.parts-group h3 { margin: 0; white-space: nowrap; display: flex; align-items: center; gap: 12px; font-size: var(--t-xl); font-weight: 900; line-height: 1.2; }
.parts-group h3::before { content: ""; flex: none; width: 22px; height: 22px; border-radius: 4px; background: var(--c); }
.parts { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.parts .card { all: unset; box-sizing: border-box; cursor: pointer; width: 100%; display: grid; grid-template-columns: 144px minmax(0, 1fr); grid-template-rows: auto 1fr; column-gap: 12px; align-items: center; padding: 10px 16px 10px 8px; border-radius: 18px; background: var(--paper); color: var(--ink); text-decoration: none; transition: transform 0.2s var(--ease); }
.parts .card:active { transform: scale(0.98); }
@media (hover: hover) { .parts .card:hover { transform: translateY(-4px); } }
.parts .card img { grid-row: span 2; width: 144px; aspect-ratio: 1; }
.parts .card b { align-self: end; font-size: var(--t-lg); font-weight: 900; line-height: 1.2; }
.parts .card span { align-self: start; margin-top: 4px; font-size: var(--t-sm); line-height: 1.45; }

/* 动效：只动 transform 和 opacity */
.js .reveal { opacity: 0; transform: translateY(28px); transition: opacity 0.8s var(--ease), transform 0.8s var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }
.part.now { transform-box: fill-box; transform-origin: center; animation: drop 0.6s var(--ease) both; }
.word > *, .level > * { animation: rise 0.5s var(--ease) both; }
.word > :nth-child(2), .level > :nth-child(2) { animation-delay: 0.05s; }
.word > :nth-child(3), .level > :nth-child(3) { animation-delay: 0.1s; }
.word-prop { animation: rise 0.6s var(--ease) both, bob 5s ease-in-out 0.6s infinite; }
.hero-art img { animation: bob 7s ease-in-out infinite; }
@keyframes drop { from { opacity: 0; transform: translateY(-18px) scale(0.96); } }
@keyframes rise { from { opacity: 0; transform: translateY(12px); } }
@keyframes bob { 50% { transform: translateY(-8px); } }
@media (prefers-reduced-motion: reduce) { .js .reveal { opacity: 1; transform: none; } }
/* 分件进场：区块进入视口后，里面的条目依次落位 */
.js .reveal .truths li, .js .reveal .steps li, .js .reveal .lv, .js .reveal .parts li { opacity: 0; transform: translateY(16px); transition: opacity 0.6s var(--ease), transform 0.6s var(--ease); transition-delay: calc(var(--k, 0) * 40ms + 150ms); }
.js .reveal.in .truths li, .js .reveal.in .steps li, .js .reveal.in .lv, .js .reveal.in .parts li { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .js .reveal .truths li, .js .reveal .steps li, .js .reveal .lv, .js .reveal .parts li { opacity: 1; transform: none; } }
.word details:not([open]) dl, .level details:not([open]) p { display: none; }
@media (max-width: 1100px) {
  .parts-group { grid-template-columns: 1fr; gap: 12px; }
  .parts .card { grid-template-columns: 1fr; grid-template-rows: auto; justify-items: center; text-align: center; padding: 6px 8px 14px; }
  .parts .card img { grid-row: auto; width: min(100%, 140px); }
  .parts .card span { display: none; }
}
@media (max-width: 900px) {
  .sheet { order: 2; }
  .parts { gap: 8px; }
  .parts .card b { font-size: var(--t-base); }
}

/* 案例出处 */
.src { flex-basis: 100%; }
.src summary { cursor: pointer; font-weight: 700; text-decoration: underline; text-underline-offset: 4px; }
.src ol { margin: 16px 0 0; padding-left: 1.4em; display: grid; gap: 10px; max-width: 46em; }
.src a { color: inherit; font-weight: 700; text-underline-offset: 3px; }
.src li span { display: block; font-size: var(--t-sm); }

/* 热词链：四段 */
.steps .act { margin: 14px 0 2px; padding-left: 12px; font-size: var(--t-sm); font-weight: 900; }
.steps .act:first-child { margin-top: 0; }
.word .act-lead { margin: 18px 0 0; padding: 12px 16px; border-radius: 12px; background: var(--cobalt-deep); font-size: var(--t-base); font-weight: 700; max-width: 38em; }
.word .deep { margin: 14px 0 0; font-size: var(--t-base); line-height: 1.75; max-width: 38em; }
.word .next { margin-top: 32px; padding-top: 24px; border-top: 2px solid rgba(255, 255, 255, 0.35); max-width: 38em; display: grid; gap: 14px; justify-items: start; }
.word .next p { margin: 0; font-size: var(--t-lg); font-weight: 700; line-height: 1.6; }
.next-btn { all: unset; box-sizing: border-box; cursor: pointer; padding: 12px 22px; border-radius: 999px; background: var(--paper); color: var(--ink); font-weight: 700; transition: transform 0.16s var(--ease); }
.next-btn:active { transform: scale(0.97); }
.next-btn:focus-visible { outline: 3px solid var(--paper); outline-offset: 3px; }

/* 3D 装配台 */
.stage { display: none; position: relative; aspect-ratio: 16 / 10; width: 100%; }
.stage canvas { display: block; width: 100%; height: 100%; cursor: grab; }
.stage canvas:active { cursor: grabbing; }
.stage span { position: absolute; left: 0; top: 0; padding: 4px 12px; border-radius: 999px; background: var(--ink); color: var(--paper); font-size: var(--t-base); font-weight: 900; white-space: nowrap; pointer-events: none; }
.sheet.is-3d .stage { display: block; }
.sheet.is-3d svg { display: none; }
.stage-hint { margin: 8px 0 0; font-size: var(--t-sm); font-weight: 700; }

/* 刚到柔、产品形态 */
.chain-more { position: relative; z-index: 1; max-width: 1320px; margin: clamp(72px, 10vh, 120px) auto 0; display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 56px); align-items: start; }
.chain-more h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; line-height: 1.25; }
.chain-more > div > p { margin: 14px 0 0; line-height: 1.7; max-width: 40em; }
.spectrum { background: var(--paper); color: var(--ink); border-radius: 18px; padding: clamp(20px, 3vw, 36px); }
.spec-ctl { margin-top: 28px; }
.spec-ctl input { width: 100%; accent-color: var(--cobalt); }
.spec-ticks { list-style: none; margin: 6px 0 0; padding: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.spec-ticks li:nth-child(2) { text-align: center; padding-right: 12%; }
.spec-ticks li:nth-child(3) { text-align: center; padding-left: 12%; }
.spec-ticks li:last-child { text-align: right; }
.spec-ticks button { all: unset; cursor: pointer; font-weight: 700; font-size: var(--t-sm); opacity: 0.6; }
.spec-ticks button.on { opacity: 1; font-weight: 900; }
.spec-ticks button:focus-visible { outline: 3px solid var(--cobalt); outline-offset: 2px; }
.spec-out { margin-top: 22px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.spec-out b { font-size: var(--t-sm); font-weight: 900; }
.spec-out p { margin: 6px 0 0; line-height: 1.6; }
.products ul { list-style: none; margin: 20px 0 0; padding: 0; display: grid; gap: 10px; }
.products li { display: grid; gap: 2px; padding: 14px 18px; border-radius: 14px; background: var(--cobalt-deep); }
.products li b { font-size: var(--t-lg); font-weight: 900; }
.products .eg { font-weight: 700; }

/* 台阶补充 */
.level .note { font-size: var(--t-sm); font-weight: 700; }

/* 零件卡片原地展开 */
.parts li.open { grid-column: 1 / -1; }
.parts li.open .card { display: none; }
.evo { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); gap: clamp(16px, 3vw, 40px); align-items: center; padding: 16px 24px; border-radius: 18px; background: var(--paper); }
.evo-art { display: flex; align-items: center; justify-content: center; gap: 8px; }
.evo-art .from { width: 38%; animation: evo-from 0.9s var(--ease) both; }
.evo-art .to { width: 52%; animation: evo-to 0.9s var(--ease) 0.25s both; }
.evo-art .arrow { font-size: var(--t-xl); font-weight: 900; animation: rise 0.5s var(--ease) 0.2s both; }
.evo-text { display: grid; gap: 8px; cursor: pointer; }
.evo-text b { font-size: var(--t-xl); font-weight: 900; }
.evo-text p { margin: 0; line-height: 1.6; }
.evo-text p:nth-of-type(1) { font-weight: 700; font-size: var(--t-lg); }
@keyframes evo-from { from { opacity: 1; transform: translateX(40%) scale(1.3); } to { opacity: 0.45; transform: none; } }
@keyframes evo-to { from { opacity: 0; transform: translateY(18px) scale(0.9); } }
@media (max-width: 900px) {
  .chain-more { grid-template-columns: 1fr; }
  .spec-out { grid-template-columns: 1fr; }
  .steps .act { grid-column: 1 / -1; }
  .levels { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .levels .lv:first-child { grid-column: 1 / -1; }
  .evo { grid-template-columns: 1fr; padding: 16px; }
}

/* 电脑上步骤列表钉在左侧 */
@media (min-width: 901px) { .steps { position: sticky; top: 88px; } }

/* 卡片展开、收起的过渡 */
::view-transition-group(*) { animation-duration: 0.45s; animation-timing-function: cubic-bezier(0.22, 1, 0.36, 1); }
::view-transition-old(*), ::view-transition-new(*) { animation-duration: 0.3s; }
.evo { animation: evo-in 0.45s cubic-bezier(0.22, 1, 0.36, 1) both; }
@keyframes evo-in { from { opacity: 0; transform: scale(0.97); } }

/* 用之前的四件事 */
.guide { padding: clamp(80px, 12vh, 140px) var(--gutter); }
.guide-head { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 64px); align-items: end; max-width: 1320px; margin: 0 auto; }
.guide-head h2 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; }
.guide-head p { margin: 0; font-size: var(--t-lg); line-height: 1.6; }
.guide-list { max-width: 1320px; margin: clamp(40px, 6vh, 72px) auto 0; display: grid; gap: 20px; }
.g-item { display: grid; grid-template-columns: minmax(0, 6fr) minmax(0, 5fr); gap: clamp(20px, 4vw, 56px); padding: clamp(20px, 3vw, 40px); border-radius: 22px; background: var(--paper); border-top: 10px solid var(--c); }
.g-text { display: grid; gap: 14px; align-content: start; grid-template-columns: minmax(0, 1fr) 120px; }
.g-text h3 { grid-column: 1; grid-row: 1; margin: 0; font-size: var(--t-xl); font-weight: 900; line-height: 1.25; align-self: center; }
.g-prop { grid-column: 2; grid-row: 1; width: 120px; aspect-ratio: 1; }
.g-text p { grid-column: 1 / -1; margin: 0; line-height: 1.75; max-width: 40em; }
.g-play { display: grid; gap: 14px; align-content: start; }
.g-ask { margin: 0; font-weight: 700; }
.picks { display: flex; flex-wrap: wrap; gap: 8px; }
.pick { all: unset; box-sizing: border-box; cursor: pointer; padding: 10px 16px; border-radius: 999px; background: var(--base-tint); font-weight: 700; line-height: 1.3; transition: background-color 0.2s var(--ease), color 0.2s var(--ease), transform 0.16s var(--ease); }
.pick:active { transform: scale(0.97); }
.pick[aria-pressed="true"] { background: var(--ink); color: var(--paper); }
.pick:focus-visible { outline: 3px solid var(--ink); outline-offset: 2px; }
.pick-out { margin: 0; padding: 16px 18px; border-radius: 14px; background: var(--base-tint); font-size: var(--t-lg); font-weight: 700; line-height: 1.5; min-height: 3.2em; }
.brief { margin: 0; padding: 16px 18px; border-radius: 14px; background: var(--base-tint); line-height: 1.75; }
.brief mark { background: none; color: inherit; font-weight: 700; box-shadow: inset 0 -0.45em 0 rgba(255, 74, 38, 0.28); }
.checks { margin: 0; padding-left: 1.4em; display: grid; gap: 6px; font-weight: 700; }
.split { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.split > div { padding: 16px 18px; border-radius: 14px; background: var(--base-tint); }
.split b { font-size: var(--t-lg); font-weight: 900; }
.split ul { margin: 10px 0 0; padding-left: 1.2em; display: grid; gap: 6px; }

/* 词典 */
.dict { margin-top: clamp(56px, 8vh, 96px); }
.dict h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; }
.dict-find { display: grid; gap: 6px; margin-top: 16px; max-width: 360px; font-weight: 700; font-size: var(--t-sm); }
.dict-find input { font: inherit; font-size: var(--t-base); padding: 12px 16px; border-radius: 999px; border: 2px solid var(--ink); background: var(--paper); color: var(--ink); }
.dict dl { margin: 28px 0 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr)); gap: 24px 48px; }
.dict dl > div { padding: 0; }
.dict dt { font-weight: 900; font-size: var(--t-lg); }
.dict dd { margin: 6px 0 0; line-height: 1.6; }
.dict-none { margin: 16px 0 0; font-weight: 700; }
@media (max-width: 900px) {
  .guide-head, .g-item { grid-template-columns: 1fr; }
  .g-text { grid-template-columns: minmax(0, 1fr) 88px; }
  .g-prop { width: 88px; }
  .split { grid-template-columns: 1fr; }
}

.parts .card:focus-visible, .evo:focus-visible, .dict-find input:focus-visible { outline: 3px solid var(--ink); outline-offset: 3px; }

/* 只有两张卡的那一组，两张卡平分整行 */
.parts:has(> li:nth-child(2):last-child) { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (max-width: 900px) { .stage span { padding: 2px 8px; font-size: 12px; } }

/* 起步怎么走 */
.start { max-width: 1320px; margin: clamp(48px, 7vh, 80px) auto 0; }
.start h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; }
.start ul { list-style: none; margin: 20px 0 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 220px), 1fr)); gap: 12px; }
.start li { display: grid; gap: 6px; align-content: start; padding: 16px 18px; border-radius: 14px; background: rgba(255, 255, 255, 0.22); }
.start b { font-size: var(--t-lg); font-weight: 900; }
.start span { line-height: 1.6; }

/* 以后再冒出新词 */
.last { background: var(--ink); color: var(--paper); padding: clamp(80px, 12vh, 140px) var(--gutter); }
.last-in { max-width: 980px; margin: 0 auto; }
.last h2 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; }
.last-in > p { margin: 20px 0 0; font-size: var(--t-lg); line-height: 1.7; max-width: 40em; }
.last-cols { margin-top: 36px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.last-cols > div { padding: 20px 22px; border-radius: 18px; background: var(--ink-soft); }
.last-cols > div:last-child { background: var(--paper); color: var(--ink); }
.last-cols h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; }
.last-cols ul { margin: 12px 0 0; padding-left: 1.2em; display: grid; gap: 8px; line-height: 1.6; font-weight: 700; }
.last .last-key { margin-top: 36px; font-size: var(--t-xl); font-weight: 900; line-height: 1.5; }
@media (max-width: 900px) { .last-cols { grid-template-columns: 1fr; } }

/* 智能体演示 */
.demo { margin-top: 26px; max-width: 46em; padding: clamp(18px, 2.5vw, 28px); border-radius: 18px; background: var(--ink); color: var(--paper); display: grid; gap: 12px; }
.demo-title { font-size: var(--t-xl); font-weight: 900; }
.demo-ask, .demo-files { margin: 0; line-height: 1.6; }
.demo-ask span, .demo-files span { display: block; font-size: var(--t-sm); font-weight: 900; color: var(--data); }
.demo-steps { list-style: none; margin: 4px 0 0; padding: 0; display: grid; gap: 10px; }
.demo-steps li { display: grid; gap: 4px; padding: 12px 14px; border-radius: 12px; background: var(--ink-soft); animation: rise 0.4s var(--ease) both; }
.demo-steps li b { font-size: var(--t-sm); font-weight: 900; color: var(--data); }
.demo-steps li em { font-style: normal; font-size: var(--t-sm); opacity: 0.85; }
.demo-steps .demo-result { background: var(--paper); color: var(--ink); }
.demo-steps .demo-result b { color: var(--tool); }
.demo-btn { justify-self: start; }
.demo-note { margin: 0; font-size: var(--t-sm); opacity: 0.85; }

/* 讲台模式：电脑横屏投影时，一屏里同时看到目录、模型和讲解。讲解长了就在自己那一栏里滚 */
@media (min-width: 1100px) and (min-height: 560px) {
  .chain-body, .ladder-body { height: calc(100svh - 104px); min-height: 520px; max-width: 1440px; scroll-margin-top: 88px; }
  .chain-body { margin-top: 48px; grid-template-columns: 220px minmax(0, 1fr); gap: 28px; align-items: stretch; }
  .steps { position: static; min-height: 0; overflow-y: auto; align-content: start; gap: 2px; scrollbar-width: thin; }
  .step { grid-template-columns: 28px 1fr; gap: 10px; padding: 5px 10px; line-height: 1.25; }
  .step .n { width: 28px; height: 28px; }
  .steps .act { margin: 10px 0 2px; }
  .sheet-wrap { grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); gap: 28px; height: 100%; min-height: 0; }
  .sheet { display: flex; flex-direction: column; height: 100%; min-height: 0; padding: 16px; }
  .stage { flex: 1; aspect-ratio: auto; min-height: 0; }
  .sheet svg { flex: 1; min-height: 0; height: 100%; }
  .word { height: 100%; min-height: 0; overflow-y: auto; padding-right: 10px; scrollbar-width: thin; }
  .word h3 { font-size: clamp(1.75rem, 1rem + 1.4vw, 2.5rem); }
  .word .one { margin-top: 14px; font-size: var(--t-lg); }
  .word-row { grid-template-columns: minmax(0, 1fr) 96px; }
  .word-prop { margin-top: 0; }
  .word dl { grid-template-columns: 1fr; }

  .ladder-body { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); align-items: stretch; }
  .ladder-art { display: flex; flex-direction: column; justify-content: center; min-height: 0; }
  .ladder-art img { flex: 1; min-height: 0; width: 100%; object-fit: contain; }
  .level { height: 100%; min-height: 0; overflow-y: auto; padding-right: 10px; scrollbar-width: thin; }
  .level h3 { font-size: clamp(1.75rem, 1rem + 1.4vw, 2.5rem); }
  .level .look { font-size: var(--t-lg); }
}

/* 顶栏跟着当前章节换颜色 */
.bar { transition: background-color 0.35s var(--ease), color 0.35s var(--ease); }
.bar[data-tone="cobalt"] { background: var(--cobalt); color: var(--paper); }
.bar[data-tone="tomato"] { background: var(--tomato); color: var(--ink); }
.bar[data-tone="ink"] { background: var(--ink); color: var(--paper); }
.bar[data-tone="cobalt"] .mark-grid i:first-child { outline: 2px solid var(--paper); outline-offset: -2px; }
@media (min-width: 1100px) and (min-height: 560px) { .products ul { grid-template-columns: repeat(2, minmax(0, 1fr)); } .products li { padding: 12px 14px; } }

/* 装配台底部：拖转提示、复位、权限说明 */
.stage-foot { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-top: 8px; }
.stage-foot .stage-hint { margin: 0; }
.stage-reset { all: unset; cursor: pointer; padding: 6px 14px; border-radius: 999px; background: var(--base-tint); font-size: var(--t-sm); font-weight: 700; transition: transform 0.16s var(--ease); }
.stage-reset:active { transform: scale(0.97); }
.stage-reset:focus-visible { outline: 3px solid var(--ink); outline-offset: 2px; }
.stage-note { margin: 6px 0 0; font-size: var(--t-sm); }
.demo-steps .demo-check { background: var(--perm); color: var(--ink); }
.demo-steps .demo-check b { color: var(--ink); }

/* AI 时代，人站在哪 */
.people { background: var(--cobalt); color: var(--paper); padding: clamp(80px, 12vh, 140px) var(--gutter); }
.people-head { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(24px, 4vw, 64px); align-items: end; max-width: 1320px; margin: 0 auto; }
.people-head h2 { margin: 0; font-size: var(--t-2xl); line-height: 1.08; font-weight: 900; }
.people-head p { margin: 0; font-size: var(--t-lg); line-height: 1.6; }
.people-list { max-width: 1320px; margin: clamp(40px, 6vh, 72px) auto 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.p-item { display: grid; gap: 14px; align-content: start; padding: clamp(20px, 3vw, 36px); border-radius: 22px; background: var(--paper); color: var(--ink); border-top: 10px solid var(--c); }
.p-item h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; line-height: 1.25; }
.p-item p { margin: 0; line-height: 1.75; }
.p-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.p-list li { display: grid; gap: 4px; padding: 14px 16px; border-radius: 14px; background: var(--base-tint); }
.p-list b { font-weight: 900; font-size: var(--t-lg); }
.p-list span { line-height: 1.7; }
.p-story { padding: 14px 16px; border-radius: 14px; background: var(--base-tint); }
.p-caveat { font-weight: 700; }
.p-take { font-size: var(--t-lg); font-weight: 900; line-height: 1.5; }
.bars { display: grid; gap: 10px; }
.bar-row { display: grid; grid-template-columns: 7.5em minmax(0, 1fr) 3.5em; gap: 10px; align-items: center; font-weight: 700; }
.bar-row i { display: block; height: 22px; border-radius: 6px; background: var(--cobalt); width: calc(var(--v) * 2%); max-width: 100%; }
.bar-row b { font-size: var(--t-lg); font-weight: 900; }
.quotes { max-width: 1320px; margin: clamp(48px, 7vh, 80px) auto 0; }
.quotes h3 { margin: 0; font-size: var(--t-xl); font-weight: 900; }
.quotes ul { list-style: none; margin: 20px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 10px; }
.quotes li { padding: 12px 18px; border-radius: 999px; background: var(--cobalt-deep); font-weight: 700; line-height: 1.4; }
@media (max-width: 900px) { .people-head, .people-list { grid-template-columns: 1fr; } }