/* ============================================================
   知行咨询 · 商务极简滚动叙事官网 (Design Demo)
   Corporate Minimalism with Motion-Led Scrollytelling
   ============================================================ */

/* ---------- 1. Tokens ---------- */
:root {
  --ink:        #0A1B33;
  --ink-2:      #0E2547;
  --ink-3:      #16325C;
  --ink-deep:   #071324;
  --paper:      #F6F8FA;
  --white:      #FFFFFF;
  --graphite:   #1B2026;
  --slate:      #5A6472;
  --slate-2:    #8A93A3;
  --on-dark:    #E8EDF4;
  --on-dark-2:  #9FB0C7;
  --blue:       #2456E6;
  --blue-deep:  #1E46C8;
  --blue-soft:  #EAF0FE;
  --gold:       #C9A469;
  --line:       rgba(27, 32, 38, .10);
  --line-dark:  rgba(232, 237, 244, .14);

  --radius-card: 16px;
  --radius-sm:   8px;

  --shadow-card: 0 1px 2px rgba(10,27,51,.05), 0 12px 32px -12px rgba(10,27,51,.14);
  --shadow-lift: 0 2px 4px rgba(10,27,51,.06), 0 20px 48px -16px rgba(10,27,51,.22);

  --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", "Cascadia Code", Consolas, "Roboto Mono", monospace;

  --container: 1200px;
  --gutter: 24px;
}

/* ---------- 2. Base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  color: var(--graphite);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { font: inherit; background: none; border: 0; cursor: pointer; }

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

::selection { background: var(--blue); color: #fff; }

/* ---------- 3. Type utilities ---------- */
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 24px;
}
.kicker::before {
  content: "";
  width: 24px;
  height: 1px;
  background: var(--blue);
}
.kicker--gold { color: var(--gold); }
.kicker--gold::before { background: var(--gold); }

.section-title {
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.2;
  color: var(--graphite);
}
.section-title--dark { color: var(--on-dark); }

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 32px;
  margin-bottom: 64px;
}
.section-head__note {
  font-size: 14px;
  color: var(--slate-2);
  white-space: nowrap;
  padding-bottom: 8px;
}

/* ---------- 4. Buttons ---------- */
.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 52px;
  padding: 0 32px;
  border-radius: 100px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .02em;
  white-space: nowrap;
  transition: background-color .3s ease, border-color .3s ease, color .3s ease;
  will-change: transform;
}
.btn--primary {
  background: var(--blue);
  color: #fff;
}
.btn--primary:hover { background: var(--blue-deep); }
.btn--ghost {
  background: transparent;
  color: var(--on-dark);
  border: 1px solid var(--line-dark);
}
.btn--ghost:hover { border-color: var(--on-dark); }
.btn--lg { height: 60px; padding: 0 44px; font-size: 16px; }
.btn__arrow { transition: transform .3s ease; }
.btn:hover .btn__arrow { transform: translateX(4px); }

/* 磁吸按钮：JS 直接写 transform，这里仅保证初始位 */
.btn--magnetic { transform: translate3d(0,0,0); }

/* ---------- 5. Card ---------- */
.card {
  background: var(--white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
}

/* ============================================================
   Preloader
   ============================================================ */
.preloader {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--ink-deep);
}
html:not(.js) .preloader { display: none; }

.preloader__inner { text-align: center; }
.preloader__text {
  display: flex;
  justify-content: center;
  gap: 8px;
  font-size: 28px;
  font-weight: 800;
  letter-spacing: .3em;
  color: var(--on-dark);
  text-indent: .3em;
}
.preloader__char { display: inline-block; }
.preloader__line {
  width: 48px;
  height: 1px;
  margin: 20px auto 0;
  background: var(--gold);
  transform-origin: center;
}

/* ============================================================
   Nav
   ============================================================ */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  background: transparent;
  transition: background-color .3s ease, box-shadow .3s ease, backdrop-filter .3s ease;
}
.nav.is-scrolled {
  background: rgba(10, 27, 51, .86);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--line-dark);
}
.nav__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
  height: 72px;
  display: flex;
  align-items: center;
  gap: 40px;
}
.nav__logo {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.nav__logo img { height: 40px; width: auto; }
.nav__logo-text {
  font-size: 16px;
  font-weight: 600;
  color: var(--on-dark);
  letter-spacing: .04em;
}
.nav__links {
  display: flex;
  gap: 32px;
  margin-left: auto;
}
.nav__link {
  position: relative;
  font-size: 14px;
  color: var(--on-dark-2);
  padding: 8px 0;
  transition: color .3s ease;
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 2px;
  height: 2px;
  background: var(--blue);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .3s ease;
}
.nav__link:hover { color: var(--on-dark); }
.nav__link.is-active { color: var(--on-dark); }
.nav__link.is-active::after { transform: scaleX(1); }
.nav__cta { display: flex; align-items: center; gap: 20px; flex-shrink: 0; }
.nav__phone {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--on-dark-2);
  font-variant-numeric: tabular-nums;
}
.nav__cta .btn { height: 40px; padding: 0 24px; font-size: 14px; }

/* 汉堡 */
.nav__burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  align-items: center;
  flex-shrink: 0;
}
.nav__burger-line {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--on-dark);
  transition: transform .3s ease;
}
.nav__burger.is-open .nav__burger-line:nth-child(1) { transform: translateY(3.75px) rotate(45deg); }
.nav__burger.is-open .nav__burger-line:nth-child(2) { transform: translateY(-3.75px) rotate(-45deg); }

/* 移动端菜单 */
.nav-mobile {
  position: fixed;
  inset: 0;
  z-index: 40;
  background: var(--ink-deep);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 0 32px;
  opacity: 0;
  visibility: hidden;
  transition: opacity .3s ease, visibility .3s ease;
}
.nav-mobile.is-open { opacity: 1; visibility: visible; }
.nav-mobile__links { display: flex; flex-direction: column; gap: 8px; }
.nav-mobile__link {
  font-size: 26px;
  font-weight: 700;
  color: var(--on-dark);
  padding: 12px 0;
  border-bottom: 1px solid var(--line-dark);
  display: block;
}
.nav-mobile__cta {
  margin-top: 48px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav-mobile__phone {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--on-dark-2);
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: var(--ink);
  overflow: hidden;
  padding: 160px 0 96px;
}
.hero__bg { position: absolute; inset: 0; pointer-events: none; }
.hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
  background-size: 120px 120px;
}
.hero__glow {
  position: absolute;
  top: -30%;
  right: -10%;
  width: 70vw;
  height: 70vw;
  background: linear-gradient(115deg, transparent 40%, rgba(36, 86, 230, .07) 55%, transparent 70%);
  transform: rotate(8deg);
}
.hero__dataline {
  position: absolute;
  left: 0; right: 0; bottom: 12%;
  width: 100%;
  height: 120px;
  opacity: .35;
}
.hero__dataline-path {
  stroke: var(--blue);
  stroke-width: 1.5;
  fill: none;
}
.hero__inner {
  position: relative;
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.hero__title {
  font-size: clamp(44px, 6vw, 76px);
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.18;
  color: var(--on-dark);
  margin-bottom: 32px;
}
.hero__title .line { display: block; }
.hero__dot { color: var(--blue); }
.hero__sub {
  max-width: 560px;
  font-size: 17px;
  color: var(--on-dark-2);
  margin-bottom: 48px;
}
.hero__actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 96px;
}
.hero__stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line-dark);
}
.stat {
  padding: 28px 24px 0 0;
}
.stat + .stat { padding-left: 24px; border-left: 1px solid var(--line-dark); }
.stat__num {
  display: block;
  font-size: 34px;
  font-weight: 700;
  color: var(--on-dark);
  line-height: 1.2;
}
.stat__label {
  display: block;
  font-size: 13px;
  color: var(--on-dark-2);
  margin-top: 4px;
  letter-spacing: .04em;
}
.hero__scroll {
  position: absolute;
  right: 40px;
  bottom: 48px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}
.hero__scroll-text {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .28em;
  color: var(--on-dark-2);
  text-transform: uppercase;
}
.hero__scroll-line {
  width: 1px;
  height: 48px;
  background: var(--on-dark-2);
}

/* ============================================================
   Trust Bar
   ============================================================ */
.trustbar {
  background: var(--ink);
  border-top: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
  padding: 48px 0;
  overflow: hidden;
}
.trustbar__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: flex;
  align-items: center;
  gap: 48px;
}
.trustbar__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold);
  white-space: nowrap;
  flex-shrink: 0;
}
.trustbar__wall { flex: 1; }
.trustbar__row {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 24px;
  padding: 8px 0;
}
.trustbar__row span {
  font-size: 14px;
  letter-spacing: .06em;
  color: var(--on-dark-2);
  white-space: nowrap;
}

/* ============================================================
   Manifesto
   ============================================================ */
.manifesto {
  padding: 144px 0;
  background: var(--paper);
}
.manifesto__inner {
  display: grid;
  grid-template-columns: 7fr 5fr;
  gap: 64px;
  align-items: center;
}
.manifesto__text .section-title { margin-bottom: 40px; }
.manifesto__p {
  font-size: 16px;
  color: var(--slate);
  max-width: 520px;
  margin-bottom: 24px;
}
.viz-card {
  background: var(--white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  padding: 32px;
}
.viz-card__svg { width: 100%; height: auto; display: block; }
.viz-grid line { stroke: var(--line); stroke-width: 1; }
.viz-line { stroke: var(--blue); stroke-width: 2; fill: none; }
.viz-node { fill: var(--blue); }
.viz-area { opacity: 1; }
.viz-card__cap {
  margin-top: 20px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--slate-2);
  text-transform: uppercase;
}

/* ============================================================
   Services
   ============================================================ */
.services {
  padding: 128px 0 144px;
  background: var(--paper);
}
.services__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.service-card {
  padding: 40px 32px 32px;
  display: flex;
  flex-direction: column;
  transition: transform .3s ease, box-shadow .3s ease;
}
.service-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
}
.service-card__top {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 32px;
}
.service-card__idx {
  font-size: 28px;
  font-weight: 500;
  color: var(--slate-2);
}
.service-card__rule { flex: 1; height: 1px; background: var(--line); }
.service-card__title {
  font-size: 22px;
  font-weight: 600;
  color: var(--graphite);
  letter-spacing: -0.01em;
  margin-bottom: 4px;
}
.service-card__en {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--slate-2);
  margin-bottom: 24px;
}
.service-card__desc {
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
  flex: 1;
  margin-bottom: 32px;
}
.card__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
  color: var(--blue);
}
.card__arrow { transition: transform .3s ease; }
.card__link:hover .card__arrow { transform: translateX(4px); }
.card__link--light { color: var(--on-dark); }

/* ============================================================
    Collab (合作方案 · 图文交错)
    ============================================================ */
.collab {
  padding: 128px 0 0;
  background: var(--paper);
  border-top: 1px solid var(--line);
}
.collab__rows {
  position: relative;
  margin-bottom: 112px;
}
/* 纵向连接线（贯穿三个方案） */
.collab__line {
  position: absolute;
  left: 50%;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
  z-index: 1;
  pointer-events: none;
}
.collab__line-fill {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background: var(--blue);
  transform: scaleY(1); /* 无 JS 完整可见；GSAP scrub 接管 */
  transform-origin: top center;
}
.collab__row {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
}
.collab__row + .collab__row { margin-top: 112px; }
.collab__row--right .collab__media { order: 2; }
.collab__row--right .collab__text { order: 1; }

/* 每方案圆点（桌面：行中线） */
.collab__dot {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 11px;
  height: 11px;
  margin: -5.5px 0 0 -5.5px;
  border-radius: 50%;
  background: var(--white);
  border: 1.5px solid var(--slate-2);
  z-index: 2;
  transition: background-color .3s ease, border-color .3s ease, box-shadow .3s ease;
}
.collab__row.is-lit .collab__dot {
  background: var(--blue);
  border-color: var(--blue);
  box-shadow: 0 0 0 5px rgba(36, 86, 230, .12);
}

/* 图片：裁剪容器 + 内层视差 + 暗色纱幕（内容未知的图片一律作氛围处理） */
.collab__media {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-card);
  aspect-ratio: 4 / 3;
  background: var(--ink);
  box-shadow: var(--shadow-card);
}
.collab__media-inner {
  position: absolute;
  inset: 0;
  will-change: transform;
}
.collab__media-inner img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.85);
}
.collab__scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(155deg, rgba(7, 19, 36, .10) 0%, rgba(7, 19, 36, .42) 100%);
  pointer-events: none;
}

.collab__text-top {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
}
.collab__idx {
  font-size: 30px;
  font-weight: 500;
  color: var(--slate-2);
}
.collab__rule { flex: 1; height: 1px; background: var(--line); }
.collab__title {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--graphite);
  margin-bottom: 6px;
}
.collab__en {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--slate-2);
  margin-bottom: 22px;
}
.collab__fit {
  font-size: 15px;
  font-weight: 600;
  color: var(--blue);
  margin-bottom: 16px;
}
.collab__desc {
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
  max-width: 480px;
  margin-bottom: 26px;
}
.collab__clients {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.collab__clients li {
  font-size: 12.5px;
  color: var(--slate);
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 100px;
  padding: 4px 14px;
  letter-spacing: .02em;
}

/* 收束引言带：全出血视差图 + 暗纱幕 */
.collab__band {
  position: relative;
  overflow: hidden;
  min-height: 440px;
  display: flex;
  align-items: center;
  background: var(--ink);
}
.collab__band-img {
  position: absolute;
  left: 0;
  right: 0;
  top: -12%;
  width: 100%;
  height: 124%;
  object-fit: cover;
  filter: saturate(.3) brightness(.72);
  will-change: transform;
}
.collab__band-scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(7, 19, 36, .78) 0%, rgba(7, 19, 36, .52) 48%, rgba(7, 19, 36, .8) 100%);
}
.collab__band-inner {
  position: relative;
  z-index: 1;
  padding: 120px var(--gutter);
  text-align: center;
}
.collab__quote {
  max-width: 820px;
  margin: 0 auto 20px;
  font-size: clamp(20px, 2.4vw, 30px);
  font-weight: 700;
  line-height: 1.65;
  letter-spacing: .01em;
  color: var(--on-dark);
}
.collab__quote-src {
  font-size: 14px;
  letter-spacing: .1em;
  color: var(--on-dark-2);
}

/* ============================================================
   Method (战略体系)
   ============================================================ */
.method {
  padding: 128px 0 144px;
  background: var(--white);
  border-top: 1px solid var(--line);
}
.method__flow {
  position: relative;
  margin-bottom: 80px;
  padding: 8px 0;
}
.method__flowline {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 40px;
  pointer-events: none;
}
.method__flowline-base { stroke: var(--line); stroke-width: 1; }
.method__flowline-draw { stroke: var(--blue); stroke-width: 1.5; }
.method__nodes {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}
.method__node {
  position: relative;
  padding-top: 48px;
  text-align: center;
}
.method__dot {
  position: absolute;
  top: 14px;
  left: 50%;
  width: 11px;
  height: 11px;
  margin-left: -5.5px;
  border-radius: 50%;
  background: var(--white);
  border: 1.5px solid var(--slate-2);
  transition: background-color .3s ease, border-color .3s ease, box-shadow .3s ease;
}
.method__node.is-lit .method__dot {
  background: var(--blue);
  border-color: var(--blue);
  box-shadow: 0 0 0 5px rgba(36, 86, 230, .12);
}
.method__node-name {
  display: block;
  font-size: 17px;
  font-weight: 600;
  color: var(--graphite);
  margin-bottom: 4px;
}
.method__node-desc {
  display: block;
  font-size: 12.5px;
  color: var(--slate-2);
  letter-spacing: .02em;
}
.method__cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.method-card {
  border-top: 1px solid var(--line);
  padding-top: 28px;
}
.method-card__idx {
  font-size: 13px;
  color: var(--gold);
  letter-spacing: .1em;
  display: block;
  margin-bottom: 12px;
}
.method-card__text {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--graphite);
}

/* ============================================================
   Cases (经典案例 · 横滚)
   ============================================================ */
.cases {
  background: var(--paper);
  border-top: 1px solid var(--line);
}
.cases__head { padding: 96px var(--gutter) 48px; }
.cases__progress {
  font-size: 15px;
  letter-spacing: .12em;
  color: var(--slate-2);
  padding-bottom: 8px;
}
.cases__pinwrap {
  /* 静态模式（无 JS / 无 GSAP / reduced-motion）：原生横向滚动 + 吸附 */
  overflow-x: auto;
  overflow-y: hidden;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: rgba(100, 116, 139, .35) transparent;
}
.case {
  scroll-snap-align: start;
}
/* GSAP 模式：transform 驱动横滚，隐藏原生滚动条 */
html.gsap .cases__pinwrap {
  overflow: hidden;
  scroll-snap-type: none;
  scrollbar-width: none;
}
html.gsap .cases__pinwrap::-webkit-scrollbar {
  display: none;
}
.cases__track {
  display: flex;
  height: calc(100vh - 72px);
  min-height: 560px;
  max-height: 820px;
  will-change: transform;
}
.case {
  flex: 0 0 100%;
  display: flex;
  align-items: center;
  padding: 0 max(24px, calc((100vw - 1200px) / 2 + 24px));
}
/* 封面屏 */
.case--cover {
  background: var(--ink);
  border-radius: var(--radius-card);
  margin: 0 16px;
  position: relative;
  overflow: hidden;
}
.case--cover::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
  background-size: 120px 120px;
}
.case__cover-inner {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 48px;
}
.case__cover-kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 32px;
}
.case__cover-title {
  font-size: clamp(32px, 4.4vw, 56px);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--on-dark);
}
.case__cover-lines {
  position: absolute;
  right: 48px;
  bottom: 64px;
  width: min(400px, 30vw);
  height: 200px;
}
.case__cover-lines path { stroke: var(--blue); stroke-width: 1.5; opacity: .5; }
.case__cover-lines path:last-child { stroke: var(--gold); opacity: .35; }

/* 案例正文屏 */
.case--body {
  gap: 48px;
  align-items: stretch;
}
.case__copy {
  flex: 0 0 5fr;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 48px 0;
}
.case__viz {
  flex: 0 0 7fr;
  position: relative;
  border-radius: var(--radius-card);
  overflow: hidden;
  background: var(--ink);
  min-height: 420px;
}
.case--mirror .case__copy { order: 2; }
.case--mirror .case__viz { order: 1; }

.case__tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 20px;
}
.case__title {
  font-size: clamp(26px, 2.8vw, 36px);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.3;
  color: var(--graphite);
  margin-bottom: 24px;
}
.case__desc {
  font-size: 15px;
  line-height: 1.9;
  color: var(--slate);
  max-width: 480px;
  margin-bottom: 40px;
}
.case__data {
  display: flex;
  gap: 56px;
  flex-wrap: wrap;
}
.case__datum-num {
  font-size: 44px;
  font-weight: 700;
  color: var(--graphite);
  line-height: 1;
}
.case__datum-unit {
  font-size: 20px;
  font-weight: 700;
  color: var(--graphite);
  margin-left: 2px;
}
.case__datum-label {
  display: block;
  font-size: 12.5px;
  color: var(--slate-2);
  margin-top: 10px;
  letter-spacing: .02em;
}

/* 案例视觉区（CSS/SVG 生成） */
.case__viz-mark {
  position: absolute;
  right: 24px;
  bottom: 16px;
  font-family: var(--font-mono);
  font-size: clamp(40px, 5vw, 68px);
  font-weight: 700;
  letter-spacing: .04em;
  color: rgba(232, 237, 244, .08);
  white-space: nowrap;
  pointer-events: none;
}
.case__viz-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px);
  background-size: 60px 60px;
}
.case__viz::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(36,86,230,.18) 0%, transparent 55%);
}
.case__viz-line {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.case__viz-line path {
  stroke: var(--blue);
  stroke-width: 1.5;
  fill: none;
  opacity: .6;
}
.case__quote {
  position: absolute;
  left: 40px;
  top: 40px;
  max-width: 60%;
  font-size: 19px;
  font-weight: 600;
  color: var(--on-dark);
  line-height: 1.5;
}
.case__quote-src {
  display: block;
  font-size: 13px;
  font-weight: 400;
  color: var(--on-dark-2);
  margin-top: 8px;
}

/* ============================================================
   About
   ============================================================ */
.about {
  padding: 144px 0;
  background: var(--paper);
  border-top: 1px solid var(--line);
}
.about__inner {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 80px;
  align-items: start;
}
.about__left { position: sticky; top: 120px; }
.about__lead {
  margin-top: 40px;
  font-size: 16px;
  color: var(--slate);
  max-width: 400px;
}
.about__industries {
  margin-top: 24px;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--slate-2);
}
.about__hqs {
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
}
.about__hqs p {
  font-size: 14px;
  color: var(--slate);
  padding: 6px 0;
}
.about__hq-label {
  display: inline-block;
  width: 88px;
  color: var(--slate-2);
  font-size: 13px;
}

.culture { margin-bottom: 40px; }
.culture__item {
  display: flex;
  align-items: baseline;
  gap: 32px;
  padding: 24px 0 24px 20px;
  border-top: 1px solid var(--line);
  position: relative;
}
.culture__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 28px;
  bottom: 28px;
  width: 2px;
  background: var(--gold);
}
.culture__key {
  flex-shrink: 0;
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--slate-2);
  width: 96px;
}
.culture__value {
  font-size: 19px;
  font-weight: 600;
  color: var(--graphite);
  letter-spacing: .01em;
}

.founder-card {
  display: grid;
  grid-template-columns: 200px 1fr;
  overflow: hidden;
}
.founder-card__avatar {
  position: relative;
  background: var(--ink);
  min-height: 280px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.founder-card__avatar-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size: 40px 40px;
}
.founder-card__avatar-char {
  position: relative;
  font-size: 96px;
  font-weight: 900;
  color: rgba(232, 237, 244, .12);
}
.founder-card__info { padding: 40px; }
.founder-card__name {
  font-size: 24px;
  font-weight: 800;
  color: var(--graphite);
  margin-bottom: 16px;
}
.founder-card__role {
  font-size: 15px;
  font-weight: 400;
  color: var(--slate-2);
}
.founder-card__titles { margin-bottom: 20px; }
.founder-card__titles li {
  font-size: 13.5px;
  color: var(--slate);
  padding: 5px 0 5px 16px;
  position: relative;
}
.founder-card__titles li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  width: 6px;
  height: 1px;
  background: var(--gold);
}
.founder-card__bio {
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ============================================================
   Insights (知行智库 · 深色)
   ============================================================ */
.insights {
  padding: 128px 0;
  background: var(--ink);
}
.insights__inner {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 40px;
  align-items: start;
}
.insights__featured {
  display: block;
  overflow: hidden;
}
.insights__featured-media {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
}
.insights__featured-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.25) brightness(.8);
}
.insights__featured-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(160deg, rgba(10,27,51,.25) 0%, rgba(10,27,51,.65) 100%);
}
.insights__featured-body { padding: 32px; }
.insights__featured-tag {
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 16px;
}
.insights__featured-title {
  font-size: 22px;
  font-weight: 700;
  line-height: 1.45;
  letter-spacing: -0.01em;
  color: var(--on-dark);
  margin-bottom: 12px;
}
.insights__featured-excerpt {
  font-size: 14px;
  color: var(--on-dark-2);
  margin-bottom: 24px;
}
.insights__featured .card__link { font-size: 14px; }

.insights__list { border-top: 1px solid var(--line-dark); }
.insights__row {
  display: grid;
  grid-template-columns: 88px 1fr auto 24px;
  align-items: center;
  gap: 24px;
  padding: 22px 16px;
  border-bottom: 1px solid var(--line-dark);
  transition: background-color .3s ease;
}
.insights__row:hover { background: var(--ink-2); }
.insights__date {
  font-size: 13px;
  color: var(--on-dark-2);
  font-variant-numeric: tabular-nums;
}
.insights__row-title {
  font-size: 15px;
  color: var(--on-dark);
  line-height: 1.6;
  transition: color .3s ease;
}
.insights__row:hover .insights__row-title { color: #fff; }
.insights__row-tag {
  font-size: 12px;
  color: var(--on-dark-2);
  white-space: nowrap;
  border: 1px solid var(--line-dark);
  border-radius: 100px;
  padding: 3px 12px;
}
.insights__row-arrow {
  color: var(--on-dark-2);
  font-size: 15px;
  transition: transform .3s ease, color .3s ease;
}
.insights__row:hover .insights__row-arrow { transform: translateX(4px); color: var(--on-dark); }

/* ============================================================
   CTA
   ============================================================ */
.cta {
  position: relative;
  background: var(--ink);
  border-top: 1px solid var(--line-dark);
  padding: 160px 0;
  overflow: hidden;
}
.cta__bg { position: absolute; inset: 0; pointer-events: none; }
.cta__dataline {
  position: absolute;
  left: 0; right: 0; bottom: 8%;
  width: 100%;
  height: 140px;
  opacity: .3;
}
.cta__dataline path { stroke: var(--blue); stroke-width: 1.5; fill: none; }
.cta__inner {
  position: relative;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.cta__title {
  font-size: clamp(40px, 5.4vw, 68px);
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.2;
  color: var(--on-dark);
  margin-bottom: 32px;
}
.cta__title .line { display: block; }
.cta__sub {
  font-size: 16px;
  color: var(--on-dark-2);
  margin-bottom: 56px;
  max-width: 560px;
}
.cta__actions {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
  justify-content: center;
}
.cta__phone {
  font-size: 16px;
  color: var(--on-dark-2);
  letter-spacing: .06em;
}

/* ============================================================
   Footer
   ============================================================ */
.footer {
  background: var(--ink-deep);
  padding: 80px 0 40px;
}
.footer__inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1.4fr 1fr;
  gap: 48px;
  padding-bottom: 56px;
  border-bottom: 1px solid var(--line-dark);
}
.footer__slogan {
  margin-top: 20px;
  font-size: 14px;
  color: var(--on-dark-2);
}
.footer__icp {
  margin-top: 12px;
  font-size: 12px;
  color: var(--slate-2);
}
.footer__col-title {
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--slate-2);
  margin-bottom: 20px;
}
.footer__col a {
  display: block;
  font-size: 14px;
  color: var(--on-dark-2);
  padding: 6px 0;
  transition: color .3s ease;
}
.footer__col a:hover { color: var(--on-dark); }
.footer__col p {
  font-size: 14px;
  color: var(--on-dark-2);
  padding: 5px 0;
  line-height: 1.7;
}
.footer__phone {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--on-dark) !important;
  letter-spacing: .04em;
}
.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 32px;
  font-size: 12px;
  color: var(--slate-2);
  flex-wrap: wrap;
}
.footer__bottom-en { letter-spacing: .12em; text-transform: uppercase; }

/* ============================================================
   9. Motion states
   规则：隐藏/位移初始态只在 html.js 存在时生效（无 JS 完整可见）
   ============================================================ */
html.js .preloader { display: flex; }

/* 入场揭示（JS 加 .is-in 或由 GSAP 接管） */
html.js .reveal {
  opacity: 0;
  transform: translate3d(0, 32px, 0);
  transition: opacity .7s cubic-bezier(.22,.61,.36,1), transform .7s cubic-bezier(.22,.61,.36,1);
}
html.js .reveal.is-in { opacity: 1; transform: translate3d(0,0,0); }

/* 标题分行（GSAP 接管，CSS 兜底初始态） */
html.js .hero__title .line,
html.js .cta__title .line {
  opacity: 0;
  transform: translate3d(0, 40px, 0);
}

/* reduced-motion：内容直出，无位移 */
@media (prefers-reduced-motion: reduce) {
  html.js .reveal,
  html.js .hero__title .line,
  html.js .cta__title .line {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  html.js .preloader { display: none; }
  .hero__scroll-line,
  .nav__burger-line { transition: none !important; }
}
html.reduced .reveal,
html.reduced .hero__title .line,
html.reduced .cta__title .line {
  opacity: 1 !important;
  transform: none !important;
  transition: none !important;
}
html.reduced .preloader { display: none; }

/* ============================================================
   10. Responsive
   ============================================================ */
@media (max-width: 1199px) {
  :root { --container: 1080px; }
  .trustbar__row { grid-template-columns: repeat(4, 1fr); }
  .about__inner { gap: 48px; }
}

@media (max-width: 1023px) {
  .nav__links, .nav__cta { display: none; }
  .nav__burger { display: flex; }
  .nav__inner { height: 64px; justify-content: space-between; }

  .hero { padding: 140px 0 80px; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); gap: 0 24px; }
  .stat { padding: 24px 0; }
  .stat:nth-child(odd) { border-left: 0; padding-left: 0; }
  .stat + .stat { border-left: 0; padding-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--line-dark); }
  .hero__scroll { display: none; }

  .trustbar__inner { flex-direction: column; align-items: flex-start; gap: 24px; }
  .trustbar__row { grid-template-columns: repeat(4, 1fr); }

  .manifesto { padding: 96px 0; }
  .manifesto__inner { grid-template-columns: 1fr; gap: 48px; }

  .services { padding: 96px 0; }
  .services__grid { grid-template-columns: 1fr; gap: 16px; }
  .section-head { flex-direction: column; align-items: flex-start; gap: 8px; margin-bottom: 40px; }

  /* 合作方案：图上文下纵向堆叠，连接线移至左侧 */
  .collab { padding: 96px 0 0; }
  .collab__rows { margin-bottom: 64px; }
  .collab__row {
    grid-template-columns: 1fr;
    gap: 32px;
    padding-left: 44px;
  }
  .collab__row + .collab__row { margin-top: 72px; }
  .collab__row--right .collab__media { order: 0; }
  .collab__row--right .collab__text { order: 1; }
  .collab__media { aspect-ratio: 16 / 10; }
  .collab__line { left: 8px; }
  .collab__dot { display: none; }
  .collab__text { position: relative; }
  .collab__text::before {
    content: "";
    position: absolute;
    left: -41px;
    top: 16px;
    width: 11px;
    height: 11px;
    border-radius: 50%;
    background: var(--white);
    border: 1.5px solid var(--slate-2);
    transition: background-color .3s ease, border-color .3s ease, box-shadow .3s ease;
  }
  .collab__row.is-lit .collab__text::before {
    background: var(--blue);
    border-color: var(--blue);
    box-shadow: 0 0 0 5px rgba(36, 86, 230, .12);
  }
  .collab__band { min-height: 0; }
  .collab__band-inner { padding: 88px var(--gutter); }

  .method { padding: 96px 0; }
  .method__flow { margin-bottom: 56px; overflow-x: auto; padding-bottom: 8px; }
  .method__nodes { min-width: 640px; }
  .method__cards { grid-template-columns: repeat(2, 1fr); gap: 32px; }

  /* 案例：纵向堆叠 */
  .cases__head { padding: 64px var(--gutter) 32px; }
  .cases__pinwrap { overflow: visible; }
  .cases__track { flex-direction: column; height: auto; min-height: 0; max-height: none; }
  .case { flex: none; width: 100%; padding: 12px var(--gutter); }
  .case--cover { margin: 0 16px; min-height: 480px; display: flex; align-items: center; }
  .case--body { flex-direction: column; gap: 0; }
  .case--mirror .case__copy { order: 1; }
  .case--mirror .case__viz { order: 2; }
  .case__copy { flex: none; padding: 40px 0; }
  .case__viz { flex: none; min-height: 360px; }

  .about { padding: 96px 0; }
  .about__inner { grid-template-columns: 1fr; gap: 56px; }
  .about__left { position: static; }

  .insights { padding: 96px 0; }
  .insights__inner { grid-template-columns: 1fr; gap: 32px; }
  .insights__row { grid-template-columns: 72px 1fr 20px; }
  .insights__row-tag { display: none; }

  .cta { padding: 112px 0; }

  .footer__inner { grid-template-columns: 1fr 1fr; gap: 40px; }
}

@media (max-width: 639px) {
  .hero__title { font-size: 36px; }
  .hero__actions .btn { width: 100%; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
  .trustbar__row { grid-template-columns: repeat(2, 1fr); }
  .stat__num { font-size: 28px; }
  .manifesto__p { font-size: 15px; }
  .case__data { gap: 32px; }
  .case__datum-num { font-size: 36px; }
  .founder-card { grid-template-columns: 1fr; }
  .founder-card__avatar { min-height: 180px; }
  .founder-card__avatar-char { font-size: 72px; }
  .founder-card__info { padding: 28px; }
  .culture__item { flex-direction: column; gap: 8px; }
  .culture__key { width: auto; }
  .insights__row { grid-template-columns: 1fr 20px; }
  .insights__date { display: none; }
  .footer__inner { grid-template-columns: 1fr; }
}