:root {
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --color-brand: #1677ff;
  --color-brand-hover: #0f68e8;
  --color-brand-soft: #eaf3ff;
  --color-ink: #17202a;
  --color-body: #566572;
  --color-muted: #72808c;
  --color-line: #dfe6ec;
  --color-surface: #ffffff;
  --color-canvas: #f7f9fb;
  --space-1: .25rem;
  --space-2: .5rem;
  --space-3: .75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
  --radius-control: .875rem;
  --radius-card: 1.25rem;
  --radius-panel: 1.75rem;
  --shadow-panel: 0 1.25rem 3.75rem rgba(28, 57, 82, .08);
  --ease-out: cubic-bezier(.16, 1, .3, 1);
}

html { scroll-padding-top: 5.5rem; }
body { font-family: var(--font-sans); background: var(--color-canvas); color: var(--color-ink); }

:where(a, button, input, textarea):focus-visible {
  outline: 3px solid color-mix(in srgb, var(--color-brand) 38%, transparent);
  outline-offset: 3px;
}

.site-header {
  min-height: 4.75rem;
  height: auto;
  padding-block: .65rem;
  border-color: color-mix(in srgb, var(--color-brand) 9%, var(--color-line));
}
.main-nav a { position: relative; }
/* Services dropdown in the primary navigation. */
.nav-dropdown { position: relative; display: inline-flex; }
.nav-dropdown-toggle { position: relative; display: inline-flex; align-items: center; gap: 7px; padding: 9px 2px; border: 0; background: none; color: inherit; font: inherit; font-size: inherit; cursor: pointer; }
.nav-dropdown-toggle::after { content: ""; width: 7px; height: 7px; border-right: 1.8px solid currentColor; border-bottom: 1.8px solid currentColor; transform: rotate(45deg) translate(-1px, -2px); transition: transform .2s var(--ease-out); }
.nav-dropdown.open .nav-dropdown-toggle::after { transform: rotate(225deg) translate(-1px, -1px); }
.nav-dropdown-toggle::before { content: ""; position: absolute; right: 0; bottom: .25rem; left: 0; height: 2px; border-radius: 999px; background: var(--color-brand); transform: scaleX(0); transform-origin: left; transition: transform .24s var(--ease-out); }
.nav-dropdown.open .nav-dropdown-toggle::before { transform: scaleX(1); }
.nav-dropdown-menu { position: absolute; top: calc(100% + .65rem); left: 0; z-index: 40; display: grid; gap: .25rem; min-width: 17.5rem; padding: .55rem; border: 1px solid var(--color-line); border-radius: 1.1rem; background: #fff; box-shadow: 0 1.4rem 3.4rem rgba(28, 57, 82, .14); opacity: 0; visibility: hidden; transform: translate(0, .5rem); transition: opacity .2s var(--ease-out), transform .2s var(--ease-out), visibility .2s; }
.nav-dropdown-menu--end { left: auto; right: 0; }
.nav-dropdown.open .nav-dropdown-menu { opacity: 1; visibility: visible; transform: translate(0, 0); }
.nav-dropdown-menu a { display: grid; gap: .2rem; padding: .8rem .95rem; border-radius: .8rem; white-space: nowrap; }
.nav-dropdown-menu a::after { display: none; }
.nav-dropdown-menu a:hover { background: var(--color-brand-soft); color: var(--color-ink); }
.nav-dropdown-menu b { color: var(--color-ink); font-size: .86rem; font-weight: 650; }
.nav-dropdown-menu small { color: var(--color-muted); font-size: .68rem; }
/* FAQ section: FAQ list + merged insights column. */
.faq-layout { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(19rem, .85fr); gap: clamp(1.5rem, 4vw, 3rem); align-items: start; margin-top: 2.5rem; }
.faq-layout .faq-list { grid-template-columns: 1fr; margin-top: 0; }
.faq-insights { position: sticky; top: 6rem; display: grid; gap: 1.25rem; padding: 1.6rem; border: 1px solid color-mix(in srgb, var(--color-brand) 16%, var(--color-line)); border-radius: var(--radius-panel); background: color-mix(in srgb, var(--color-brand-soft) 42%, #fff); box-shadow: var(--shadow-panel); }
.faq-insights-head small { color: var(--color-brand); font-size: .66rem; font-weight: 750; letter-spacing: .1em; }
.faq-insights-head h3 { margin: .7rem 0 .5rem; color: var(--color-ink); font-size: 1.45rem; line-height: 1.3; letter-spacing: -.02em; }
.faq-insights-head h3 em { color: var(--color-brand); font-style: normal; }
.faq-insights-head p { margin: 0; color: var(--color-body); font-size: .8rem; line-height: 1.7; }
.faq-insights-list { display: grid; border-top: 1px solid color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); }
.faq-insights-list a { display: grid; gap: .25rem; padding: .85rem .2rem; border-bottom: 1px solid color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); transition: padding-left .2s var(--ease-out); }
.faq-insights-list a:hover { padding-left: .55rem; }
.faq-insights-list b { color: var(--color-ink); font-size: .86rem; line-height: 1.5; }
.faq-insights-list span { color: var(--color-muted); font-size: .68rem; }
.faq-insights-more { display: inline-flex; align-items: center; gap: .4rem; color: var(--color-brand); font-size: .82rem; font-weight: 700; }
.main-nav a::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: .25rem;
  left: 0;
  height: 2px;
  border-radius: 999px;
  background: var(--color-brand);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .24s var(--ease-out);
}
.main-nav a:hover::after,
.main-nav a:focus-visible::after { transform: scaleX(1); }
.header-cta,
.btn { font-weight: 600; transition: transform .18s var(--ease-out), background-color .18s, border-color .18s, box-shadow .18s; }
.header-cta:active,
.btn:active { transform: scale(.98); }

.hero { padding-top: clamp(3.5rem, 7vw, 6rem); }
.hero-grid { gap: clamp(2.5rem, 6vw, 5.25rem); }
h1, h2, h3 { text-wrap: balance; }
h1 { max-width: 9.5ch; font-weight: 650; }
.hero-lead { max-width: 34rem; color: var(--color-body); }
.hero-lead strong { color: var(--color-ink); font-weight: 750; }
.hero-proof { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }

/* Hero production map: use a stable three-stage flow instead of free-positioned nodes. */
.production-map { display: grid; grid-template-columns: minmax(7.5rem, 1fr) 1.2rem minmax(9rem, 1.18fr) 1.2rem minmax(7.5rem, 1fr); align-items: center; gap: .45rem; min-height: 32.5rem; height: auto; padding: 1.25rem; overflow: hidden; }
.production-map .map-column { display: grid; grid-template-rows: 1.2rem repeat(3, 5.8rem); align-content: center; gap: .55rem; min-width: 0; }
.production-map .map-inputs,
.production-map .map-results { width: 100%; }
.production-map .map-card { height: 5.8rem; }
.production-map .map-label { margin-bottom: .15rem; color: var(--color-muted); font-size: .62rem; font-weight: 700; letter-spacing: .12em; }
.production-map .map-card { position: relative; min-width: 0; padding: .9rem .85rem; border: 1px solid var(--color-line); border-radius: .8rem; background: var(--color-surface); box-shadow: 0 .45rem 1.3rem rgba(31, 57, 80, .045); }
.production-map .map-card small { display: block; color: var(--color-muted); font-size: .55rem; font-weight: 700; letter-spacing: .1em; }
.production-map .map-card b { display: block; margin: .3rem 0 .2rem; color: var(--color-ink); font-size: .82rem; line-height: 1.35; }
.production-map .map-card span { display: block; color: var(--color-muted); font-size: .62rem; line-height: 1.45; white-space: normal; }
.production-map .result-card { padding-left: 2.05rem; border-color: color-mix(in srgb, var(--color-brand) 18%, var(--color-line)); background: color-mix(in srgb, var(--color-brand-soft) 32%, #fff); }
.production-map .map-inputs .map-card,
.production-map .map-results .map-card { display: flex; flex-direction: column; justify-content: center; }
.production-map .result-card > i { position: absolute; top: .85rem; left: .75rem; color: var(--color-brand); font-size: .62rem; font-style: normal; font-weight: 750; }
.production-map .map-core { align-self: center; min-width: 0; padding: 1.35rem .8rem; border: 1px solid color-mix(in srgb, var(--color-brand) 30%, var(--color-line)); border-radius: 1.2rem; background: linear-gradient(180deg, #f5f9ff, #eaf3ff); text-align: center; box-shadow: 0 1rem 2.5rem rgba(22, 119, 255, .1); }
.production-map .map-core > small { display: block; color: var(--color-brand); font-size: .5rem; font-weight: 750; line-height: 1.45; letter-spacing: .055em; white-space: normal; overflow-wrap: anywhere; }
.production-map .map-core .core-ring { width: 4.25rem; height: 4.25rem; margin: .85rem auto; }
.production-map .map-core .core-ring span { font-size: 1rem; }
.production-map .map-core > b { display: block; color: var(--color-ink); font-size: .86rem; }
.production-map .map-core > p { margin: .65rem 0 0; color: var(--color-muted); font-size: .59rem; line-height: 1.7; }
.production-map .map-flow { display: grid; justify-items: center; gap: .5rem; min-width: 0; }
.production-map .map-flow span { position: relative; display: block; width: 100%; height: 1px; background: color-mix(in srgb, var(--color-brand) 42%, var(--color-line)); }
.production-map .map-flow span::after { content: ""; position: absolute; top: 50%; right: -1px; width: .42rem; height: .42rem; border-top: 1px solid var(--color-brand); border-right: 1px solid var(--color-brand); transform: translateY(-50%) rotate(45deg); }
.production-map .map-flow i { color: var(--color-muted); font-size: .52rem; font-style: normal; writing-mode: vertical-rl; letter-spacing: .08em; }
.hero-proof div { min-height: 6.5rem; display: flex; flex-direction: column; justify-content: center; }
.hero-proof strong { font-size: .95rem; line-height: 1.25; color: var(--color-ink); }
.hero-proof span { font-size: .76rem; line-height: 1.55; color: var(--color-muted); }

.section,
.platform-section,
.contact-section { padding-top: clamp(4.75rem, 8vw, 7.25rem); padding-bottom: clamp(4.75rem, 8vw, 7.25rem); }
.section-heading p,
.platform-intro p,
.contact-copy > p { max-width: 38rem; color: var(--color-body); }

/* SEO / GEO FAQ: visible answers help users, Baiduspider and AI retrieval systems understand key entities. */
.faq-section { background: #fff; }
.faq-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin-top: 2.5rem; }
.faq-item { border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); box-shadow: 0 .6rem 1.8rem rgba(28, 57, 82, .04); overflow: clip; }
.faq-item[open] { border-color: color-mix(in srgb, var(--color-brand) 24%, var(--color-line)); box-shadow: 0 .8rem 2rem rgba(22, 119, 255, .06); }
.faq-item summary { position: relative; padding: 1.25rem 3.1rem 1.25rem 1.35rem; color: var(--color-ink); font-size: 1rem; font-weight: 700; line-height: 1.55; cursor: pointer; list-style: none; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; position: absolute; top: 50%; right: 1.3rem; width: 1.6rem; height: 1.6rem; border-radius: 50%; background: var(--color-brand-soft); color: var(--color-brand); font-size: 1.15rem; font-weight: 500; line-height: 1.5rem; text-align: center; transform: translateY(-50%); }
.faq-item[open] summary::after { content: "−"; }
.faq-item p { margin: 0; padding: 0 1.35rem 1.35rem; color: var(--color-body); font-size: .9rem; line-height: 1.8; }
.faq-item summary:focus-visible { outline-offset: -4px; }
.section-kicker,
.eyebrow { font-size: .75rem; line-height: 1.4; }
.contact-wechat { display: grid; grid-template-columns: 7.5rem 1fr; gap: 1rem; align-items: center; max-width: 31rem; margin-top: 1.25rem; padding: .9rem; border: 1px solid color-mix(in srgb, var(--color-brand) 18%, var(--color-line)); border-radius: var(--radius-card); background: color-mix(in srgb, var(--color-brand-soft) 48%, #fff); }
.contact-wechat img { width: 7.5rem; height: 7.5rem; padding: .25rem; border-radius: .8rem; background: #fff; object-fit: contain; }
.contact-wechat small { display: block; margin-bottom: .25rem; color: var(--color-brand); font-size: .68rem; font-weight: 750; letter-spacing: .08em; }
.contact-wechat strong { display: block; color: var(--color-ink); font-size: 1rem; line-height: 1.45; }
.contact-wechat p { margin: .45rem 0 0; color: var(--color-body); font-size: .78rem; line-height: 1.65; }

.problem-grid { gap: 0; border-top: 1px solid var(--color-line); border-bottom: 1px solid var(--color-line); }
.problem-card {
  border: 0;
  border-radius: 0;
  box-shadow: none;
  padding: 2.25rem 1.75rem 2rem;
  background: transparent;
}
.problem-card + .problem-card { border-left: 1px solid var(--color-line); }
.problem-card:hover { transform: translateY(-3px); background: color-mix(in srgb, var(--color-brand-soft) 44%, transparent); }
.problem-card h3 { margin-top: 1.65rem; }
.problem-card p { color: var(--color-body); }
.problem-card small { font-size: .68rem; }

.fde-section { display: block; padding-top: clamp(4.5rem, 7vw, 6.5rem); padding-bottom: clamp(4.5rem, 7vw, 6.5rem); }
/* Compact FDE overview: introduction first, four delivery stages directly below. */
.fde-sticky { position: static; top: auto; display: grid; grid-template-columns: minmax(18rem, .8fr) minmax(0, 1.2fr); grid-template-rows: auto auto 1fr; column-gap: clamp(2rem, 5vw, 4.5rem); width: min(var(--max), calc(100% - 3rem)); margin: 0 auto 1.25rem; padding: clamp(1.5rem, 3vw, 2.25rem); border: 1px solid color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); border-radius: var(--radius-panel); background: color-mix(in srgb, var(--color-brand-soft) 46%, #fff); align-self: start; }
.fde-sticky > .section-kicker { grid-column: 1; grid-row: 1; }
.fde-sticky h2 { grid-column: 1; grid-row: 2 / 5; max-width: 12ch; margin: 1rem 0 0; font-size: clamp(2rem, 3.5vw, 3.35rem); }
.fde-sticky > p,
.fde-sticky > .fde-brand-link,
.fde-sticky > .fde-difference,
.fde-sticky > .text-link { grid-column: 2; }
.fde-sticky > p { margin: 0; max-width: 58rem; font-size: .9rem; line-height: 1.7; }
.fde-sticky > .fde-brand-link { margin: .85rem 0 1rem; }
.fde-sticky > .fde-difference { margin: 0 0 .9rem; }
.fde-sticky .text-link { margin-top: 0; }
.fde-steps { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px; width: min(var(--max), calc(100% - 3rem)); margin: 0 auto; overflow: hidden; border: 1px solid var(--color-line); border-radius: var(--radius-panel); background: var(--color-line); box-shadow: var(--shadow-panel); }
.fde-step { min-width: 0; padding: 1.5rem; background: var(--color-surface); }
.fde-step + .fde-step { border-top: 0; }
.fde-step h3 { min-height: 4.6rem; margin: .9rem 0 .7rem; font-size: 1.15rem; line-height: 1.45; }
.fde-step p { min-height: 8rem; margin: 0; font-size: .82rem; line-height: 1.7; }
.fde-step .fde-output { display: block; min-height: 5.4rem; margin: 1rem 0; padding: .8rem; }
.fde-step .fde-output b,
.fde-step .fde-output span { display: block; }
.fde-step .fde-output span { margin-top: .35rem; }
.fde-step ul { display: grid; gap: .4rem; margin: 0; }
.fde-step li { padding: .55rem .7rem; font-size: .72rem; }
/* Keep the FDE introduction in normal document flow instead of following the viewport. */
.fde-sticky h2 { color: var(--color-ink); }
.fde-sticky > p { color: var(--color-body); }
.fde-brand-link span { border-color: color-mix(in srgb, var(--color-brand) 20%, var(--color-line)); background: color-mix(in srgb, var(--color-brand-soft) 62%, #fff); color: var(--color-ink); }
.fde-brand-link i { color: var(--color-muted); }
.fde-difference div { border-top-color: color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); }
.fde-difference strong { color: var(--color-ink); }
.fde-difference span { color: var(--color-body); }
.fde-step { padding: 2.25rem 0 2.5rem; border-radius: 0; background: transparent; box-shadow: none; }
.fde-step + .fde-step { border-top: 1px solid color-mix(in srgb, var(--color-brand) 12%, var(--color-line)); }
.fde-step > span { font-size: .72rem; }
.fde-step p { max-width: 38rem; color: var(--color-body); }
.fde-step ul { gap: .6rem; }
.fde-step li { background: var(--color-surface); border: 1px solid color-mix(in srgb, var(--color-brand) 12%, var(--color-line)); }
.fde-brand-link { display: flex; flex-wrap: wrap; align-items: center; gap: .45rem; margin: 1.25rem 0 1.6rem; }
.fde-brand-link span { padding: .38rem .65rem; border: 1px solid rgba(255, 255, 255, .16); border-radius: 999px; background: rgba(255, 255, 255, .06); color: rgba(255, 255, 255, .86); font-size: .68rem; line-height: 1.35; }
.fde-brand-link i { color: rgba(255, 255, 255, .35); font-size: .7rem; font-style: normal; }
.fde-difference { display: grid; gap: .7rem; margin: 1.4rem 0 1.75rem; }
.fde-difference div { display: grid; grid-template-columns: 5.25rem 1fr; gap: .8rem; padding-top: .75rem; border-top: 1px solid rgba(255, 255, 255, .14); }
.fde-difference strong { color: #fff; font-size: .82rem; }
.fde-difference span { color: rgba(255, 255, 255, .65); font-size: .76rem; line-height: 1.55; }
/* Light FDE surface contrast overrides. Keep these after the legacy dark-theme rules. */
.fde-brand-link span { border-color: color-mix(in srgb, var(--color-brand) 20%, var(--color-line)); background: color-mix(in srgb, var(--color-brand-soft) 62%, #fff); color: var(--color-ink); }
.fde-brand-link i { color: var(--color-muted); }
.fde-difference div { border-top-color: color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); }
.fde-difference strong { color: var(--color-ink); }
.fde-difference span { color: var(--color-body); }
.fde-output { display: grid; grid-template-columns: 5.25rem 1fr; gap: .9rem; margin: 1.25rem 0; padding: .8rem 1rem; border-radius: .9rem; background: color-mix(in srgb, var(--color-brand-soft) 62%, #fff); }
.fde-output b { color: var(--color-brand); font-size: .74rem; }
.fde-output span { color: var(--color-body); font-size: .76rem; line-height: 1.5; }

.fde-detail,
.fde-team,
.fde-boundary,
.fde-success { grid-column: 1 / -1; width: min(var(--max), calc(100% - 3rem)); margin-inline: auto; }
.fde-detail { display: grid; grid-template-columns: minmax(18rem, .76fr) minmax(0, 1.24fr); gap: clamp(2.5rem, 6vw, 5.5rem); margin-top: clamp(4.5rem, 9vw, 8rem); padding-top: clamp(3.5rem, 7vw, 6rem); border-top: 1px solid color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); }
.fde-detail-intro h3 { max-width: 15ch; margin: 1.25rem 0; color: var(--color-ink); font-size: clamp(2rem, 3.5vw, 3.15rem); line-height: 1.22; letter-spacing: -.035em; }
.fde-detail-intro p { max-width: 34rem; color: var(--color-body); line-height: 1.85; }
.fde-responsibilities { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1px; overflow: hidden; border: 1px solid var(--color-line); border-radius: var(--radius-panel); background: var(--color-line); box-shadow: var(--shadow-panel); }
.fde-responsibilities article { min-height: 11.5rem; padding: 1.45rem; background: var(--color-surface); }
.fde-responsibilities article > span { color: var(--color-brand); font-size: .68rem; font-weight: 750; letter-spacing: .08em; }
.fde-responsibilities h4 { margin: 1.5rem 0 .55rem; color: var(--color-ink); font-size: 1rem; }
.fde-responsibilities p { margin: 0; color: var(--color-body); font-size: .78rem; line-height: 1.7; }
.fde-team { display: grid; grid-template-columns: minmax(18rem, .72fr) minmax(0, 1.28fr); gap: clamp(2.5rem, 7vw, 6rem); align-items: center; margin-top: clamp(4.5rem, 8vw, 7rem); padding: clamp(2rem, 5vw, 4rem); border-radius: var(--radius-panel); background: color-mix(in srgb, var(--color-brand-soft) 65%, #fff); }
.fde-team-copy > small,
.fde-boundary-head small,
.fde-success > div > small { color: var(--color-brand); font-size: .66rem; font-weight: 750; letter-spacing: .1em; }
.fde-team-copy h3,
.fde-boundary-head h3,
.fde-success h3 { margin: .9rem 0; color: var(--color-ink); font-size: clamp(1.65rem, 3vw, 2.5rem); line-height: 1.25; letter-spacing: -.03em; }
.fde-team-copy p,
.fde-success > div > p { color: var(--color-body); line-height: 1.8; }
.fde-team-map { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .75rem; }
.team-role,
.team-core { min-height: 6.5rem; padding: 1.1rem; border: 1px solid color-mix(in srgb, var(--color-brand) 14%, var(--color-line)); border-radius: var(--radius-card); background: rgba(255, 255, 255, .8); }
.team-role span { display: block; color: var(--color-ink); font-size: .88rem; font-weight: 650; }
.team-role small { display: block; margin-top: .5rem; color: var(--color-muted); font-size: .7rem; line-height: 1.5; }
.team-core { grid-column: 1 / -1; display: grid; grid-template-columns: 4.5rem 1fr; align-items: center; min-height: 5.5rem; border-color: var(--color-brand); background: var(--color-brand); color: #fff; }
.team-core b { font-size: 1.35rem; }
.team-core span { font-size: .78rem; line-height: 1.55; }
.fde-boundary { margin-top: clamp(4.5rem, 8vw, 7rem); }
.fde-boundary-head { display: flex; justify-content: space-between; align-items: end; gap: 2rem; margin-bottom: 2rem; }
.fde-boundary-head h3 { margin-bottom: 0; }
.fde-boundary-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1rem; }
.fde-boundary-grid article { display: flex; flex-direction: column; min-height: 17.5rem; padding: 1.45rem; border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); }
.fde-boundary-grid article > span { color: var(--color-muted); font-size: .7rem; font-weight: 750; }
.fde-boundary-grid p { color: var(--color-body); font-size: .78rem; line-height: 1.7; }
.fde-boundary-grid strong { margin-top: auto; padding-top: 1rem; border-top: 1px solid var(--color-line); color: var(--color-ink); font-size: .78rem; line-height: 1.65; }
.fde-success { display: grid; grid-template-columns: minmax(18rem, .75fr) minmax(0, 1.25fr); gap: clamp(2.5rem, 7vw, 6rem); margin-top: clamp(4.5rem, 8vw, 7rem); padding: clamp(2rem, 5vw, 4rem); border-radius: var(--radius-panel); background: #17202a; }
.fde-success h3 { color: #fff; }
.fde-success > div > p { color: rgba(255, 255, 255, .62); }
.fde-success ul { display: grid; gap: 0; margin: 0; padding: 0; list-style: none; }
.fde-success li { display: grid; grid-template-columns: 6rem 1fr; gap: 1rem; padding: 1rem 0; border-bottom: 1px solid rgba(255, 255, 255, .12); }
.fde-success li:last-child { border-bottom: 0; }
.fde-success li b { color: #fff; font-size: .82rem; }
.fde-success li span { color: rgba(255, 255, 255, .65); font-size: .76rem; line-height: 1.55; }

.about-section { background: var(--color-surface); }
.about-layout { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(22rem, .95fr); gap: clamp(2.5rem, 7vw, 6rem); align-items: start; }
.about-copy h2 { margin-bottom: 1.75rem; }
.about-copy > p { max-width: 42rem; color: var(--color-body); font-size: .98rem; line-height: 1.9; }
.about-copy .about-lead { color: var(--color-ink); font-size: 1.1rem; font-weight: 500; }
.about-copy blockquote { margin: 2rem 0 0; padding: 1.35rem 1.5rem; border-left: 3px solid var(--color-brand); border-radius: 0 var(--radius-control) var(--radius-control) 0; background: var(--color-brand-soft); color: var(--color-ink); font-size: 1rem; line-height: 1.75; }
.about-capabilities { border-top: 1px solid var(--color-line); }
.about-capabilities article { display: grid; grid-template-columns: 2.5rem 1fr; gap: 1.1rem; padding: 1.35rem 0; border-bottom: 1px solid var(--color-line); }
.about-capabilities article > span { color: var(--color-brand); font-size: .72rem; font-weight: 700; letter-spacing: .08em; }
.about-capabilities h3 { margin: 0 0 .35rem; font-size: 1.05rem; }
.about-capabilities p { margin: 0; color: var(--color-body); font-size: .84rem; line-height: 1.65; }

.solution-tabs,
.role-buttons { scrollbar-width: thin; }
.solution-tabs button,
.role-buttons button { min-height: 2.875rem; }
.solution-tabs button[aria-selected="true"],
.role-buttons button[aria-selected="true"] { background: var(--color-brand); color: #fff; border-color: var(--color-brand); }
.solution-display { box-shadow: var(--shadow-panel); }
.solution-content p { color: var(--color-body); }
.solution-results { grid-template-columns: max-content minmax(8rem, 1fr); column-gap: 1rem; row-gap: .8rem; }
.solution-results strong { font-size: .95rem; line-height: 1.4; text-align: right; }
.ai-dev-showcase { margin-top: clamp(4rem, 8vw, 7rem); padding-top: clamp(3.5rem, 7vw, 6rem); border-top: 1px solid var(--color-line); }
.ai-dev-intro { display: grid; grid-template-columns: minmax(0, 1fr) minmax(20rem, .7fr); column-gap: clamp(2rem, 7vw, 6rem); align-items: end; }
.ai-dev-intro .section-kicker { grid-column: 1 / -1; }
.ai-dev-intro h2 { margin-bottom: 0; }
.ai-dev-intro p { margin: 0; color: var(--color-body); line-height: 1.8; }
.ai-dev-intro .text-link { grid-column: 2; margin-top: 1.25rem; justify-self: start; }
.ai-dev-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px; margin-top: 3rem; overflow: hidden; border: 1px solid var(--color-line); border-radius: var(--radius-panel); background: var(--color-line); box-shadow: var(--shadow-panel); }
.ai-dev-grid article { min-height: 22rem; padding: 1.7rem 1.5rem; background: var(--color-surface); }
.ai-dev-grid article > span { display: inline-flex; margin-bottom: 2.5rem; color: var(--color-brand); font-size: .72rem; font-weight: 700; letter-spacing: .08em; }
.ai-dev-grid h3 { margin-bottom: .8rem; font-size: 1.05rem; }
.ai-dev-grid p { min-height: 6.5rem; color: var(--color-body); font-size: .83rem; line-height: 1.7; }
.ai-dev-grid ul { display: grid; gap: .55rem; margin: 1.25rem 0 0; padding: 0; list-style: none; }
.ai-dev-grid li { color: var(--color-muted); font-size: .75rem; }
.ai-dev-grid li::before { content: ""; display: inline-block; width: .35rem; height: .35rem; margin-right: .55rem; border-radius: 999px; background: var(--color-brand); vertical-align: .08em; }
.ai-dev-types { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1rem; margin-top: 1rem; }
.ai-dev-types div { display: flex; flex-direction: column; min-height: 9.5rem; padding: 1.25rem; border: 1px solid var(--color-line); border-radius: var(--radius-card); background: color-mix(in srgb, var(--color-brand-soft) 38%, #fff); }
.ai-dev-types small { color: var(--color-brand); font-size: .68rem; font-weight: 700; }
.ai-dev-types strong { margin: .65rem 0 .4rem; font-size: .88rem; line-height: 1.45; }
.ai-dev-types span { color: var(--color-muted); font-size: .74rem; line-height: 1.55; }

.stack-diagram { box-shadow: var(--shadow-panel); }
.stack-row { min-height: 5.75rem; }
.stack-row p { max-width: 31rem; }
.stack-row a { display: inline-flex; margin-top: .5rem; color: var(--color-brand); font-size: .72rem; font-weight: 700; }
.fde-links,
.ai-dev-links { display: flex; flex-wrap: wrap; gap: 1rem 1.5rem; }
.ai-dev-intro .ai-dev-links { grid-column: 2; margin-top: 1.25rem; }

.case-label { background: #fff5df; color: #7a5415; border-color: #f0dcae; }
.before-after small,
.privacy { font-size: .625rem; line-height: 1.5; }
.case-chart { opacity: .55; }
.case-kpis { grid-template-columns: 1fr; gap: .8rem; }
.case-kpis div { display: grid; grid-template-columns: minmax(8rem, .75fr) 1fr; align-items: baseline; gap: 1.25rem; padding: .85rem 0; border-bottom: 1px solid var(--color-line); }
.case-kpis strong { font-size: .95rem; }
.case-kpis span { margin-top: 0; }

.role-content p { max-width: 40rem; color: var(--color-body); }
.contact-form input,
.contact-form textarea { min-height: 3rem; }
.contact-form textarea { min-height: 6.5rem; }
.form-head span { max-width: 17rem; line-height: 1.45; text-align: right; }
.form-success { display: none; }
.form-success.show { display: grid; }

.floating-contact { position: fixed; right: clamp(1rem, 2.4vw, 2rem); bottom: clamp(1rem, 2.4vw, 2rem); z-index: 60; display: grid; justify-items: end; gap: .75rem; }
.floating-contact-trigger { display: inline-flex; align-items: center; gap: .55rem; min-height: 3.25rem; padding: 0 1.15rem; border: 0; border-radius: 999px; background: var(--color-brand); color: #fff; font-weight: 650; box-shadow: 0 .9rem 2.2rem rgba(22, 119, 255, .28); cursor: pointer; transition: transform .2s var(--ease-out), background-color .2s, box-shadow .2s; }
.floating-contact-trigger:hover { background: var(--color-brand-hover); transform: translateY(-2px); box-shadow: 0 1.1rem 2.6rem rgba(22, 119, 255, .34); }
.floating-contact-symbol { display: grid; place-items: center; width: 1.55rem; height: 1.55rem; border-radius: 999px; background: rgba(255, 255, 255, .18); }
.floating-contact-panel { display: none; width: min(22rem, calc(100vw - 2rem)); padding: 1.15rem; border: 1px solid var(--color-line); border-radius: var(--radius-card); background: rgba(255, 255, 255, .98); box-shadow: 0 1.4rem 4rem rgba(28, 57, 82, .18); backdrop-filter: blur(18px); }
.floating-contact-panel.open { display: block; animation: contactPanelIn .24s var(--ease-out); }
.floating-contact-head { display: flex; justify-content: space-between; gap: 1rem; padding: .15rem .15rem 1rem; }
.floating-contact-head strong { display: block; color: var(--color-ink); font-size: 1rem; }
.floating-contact-head span { display: block; margin-top: .35rem; color: var(--color-muted); font-size: .74rem; line-height: 1.5; }
.floating-contact-close { flex: 0 0 2rem; width: 2rem; height: 2rem; border: 0; border-radius: 999px; background: var(--color-canvas); color: var(--color-muted); font-size: 1.2rem; cursor: pointer; }
.wechat-contact-card { display: grid; grid-template-columns: 8.5rem 1fr; gap: 1rem; align-items: center; margin-bottom: .75rem; padding: .8rem; border: 1px solid color-mix(in srgb, var(--color-brand) 16%, var(--color-line)); border-radius: 1rem; background: color-mix(in srgb, var(--color-brand-soft) 40%, #fff); }
.wechat-contact-card img { display: block; width: 8.5rem; height: 8.5rem; object-fit: contain; border-radius: .75rem; background: #fff; }
.wechat-contact-card b { display: block; color: var(--color-ink); font-size: .88rem; }
.wechat-contact-card span { display: block; margin-top: .45rem; color: var(--color-muted); font-size: .7rem; line-height: 1.6; }
.floating-contact-options { display: grid; gap: .6rem; }
.floating-contact-options a { display: grid; grid-template-columns: 2.25rem 1fr auto; align-items: center; gap: .75rem; padding: .85rem; border: 1px solid var(--color-line); border-radius: .9rem; background: #fff; transition: border-color .2s, background-color .2s; }
.floating-contact-options a:hover { border-color: color-mix(in srgb, var(--color-brand) 38%, var(--color-line)); background: var(--color-brand-soft); }
.contact-icon { display: grid; place-items: center; width: 2.25rem; height: 2.25rem; border-radius: .7rem; background: var(--color-brand-soft); color: var(--color-brand); font-weight: 750; }
.floating-contact-options b { display: block; color: var(--color-ink); font-size: .82rem; }
.floating-contact-options small { display: block; margin-top: .2rem; color: var(--color-muted); font-size: .66rem; line-height: 1.4; }
.floating-contact-options i { color: var(--color-brand); font-style: normal; }
.floating-contact-panel > p { margin: .8rem .15rem 0; color: var(--color-muted); font-size: .62rem; line-height: 1.5; }
@keyframes contactPanelIn { from { opacity: 0; transform: translateY(.65rem) scale(.98); } to { opacity: 1; transform: none; } }

.brand small,
.footer-brand small { font-size: .625rem; }
.node small,
.node span,
.ui-sidebar small,
.ui-main small,
.stack-row small,
.fde-badge small,
.trust-logos small,
.problem-card small { font-size: .625rem; }
.nav-toggle { min-width: 2.75rem; min-height: 2.75rem; align-items: center; justify-content: center; }

@media (max-width: 1100px) {
  .production-map { grid-template-columns: minmax(7rem, 1fr) .8rem minmax(8.5rem, 1.15fr) .8rem minmax(7rem, 1fr); gap: .35rem; min-height: 31rem; padding: .85rem; }
  .production-map .map-card { padding: .8rem .7rem; }
  .production-map .result-card { padding-left: 1.9rem; }
  .fde-sticky { grid-template-columns: 1fr; }
  .fde-sticky > .section-kicker,
  .fde-sticky h2,
  .fde-sticky > p,
  .fde-sticky > .fde-brand-link,
  .fde-sticky > .fde-difference,
  .fde-sticky > .text-link { grid-column: 1; grid-row: auto; }
  .fde-sticky h2 { max-width: 16ch; margin-bottom: 1rem; }
  .fde-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .fde-step h3,
  .fde-step p { min-height: auto; }
  .fde-detail,
  .fde-team,
  .fde-success { grid-template-columns: 1fr; }
  .fde-boundary-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .fde-boundary-grid article { min-height: 14rem; }
  .problem-card:nth-child(3) { border-left: 0; border-top: 1px solid var(--color-line); }
  .problem-card:nth-child(4) { border-top: 1px solid var(--color-line); }
  .ai-dev-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .ai-dev-grid article { min-height: 19rem; }
  .ai-dev-types { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 720px) {
  html { scroll-padding-top: 4.75rem; }
  .site-header { min-height: 4.25rem; }
  .nav-toggle { display: flex; }
  .nav-dropdown { display: grid; }
  .nav-dropdown-toggle { justify-content: space-between; width: 100%; padding: 12px 14px; border-radius: 10px; }
  .nav-dropdown-toggle:hover { background: var(--color-brand-soft); }
  .nav-dropdown-toggle::before { display: none; }
  .nav-dropdown-menu { position: static; min-width: 0; padding: 0 0 0 .75rem; border: 0; border-radius: 0; box-shadow: none; opacity: 1; visibility: visible; transform: none; display: none; }
  .nav-dropdown.open .nav-dropdown-menu { display: grid; transform: none; opacity: 1; visibility: visible; }
  .nav-dropdown-menu a { white-space: normal; }
  .faq-layout { grid-template-columns: 1fr; }
  .faq-insights { position: static; }
  .hero { padding-top: 3rem; }
  h1 { max-width: 10ch; }
  .production-map { grid-template-columns: 1fr; align-content: start; height: auto; padding: 1rem; gap: .85rem; overflow: visible; }
  .production-map .map-column { grid-template-rows: auto; gap: .55rem; }
  .production-map .map-card { height: auto; }
  .production-map .map-label { margin-top: .2rem; }
  .production-map .map-flow { display: none; }
  .production-map .map-core { grid-row: 2; display: grid; grid-template-columns: 3.5rem 1fr; align-items: center; column-gap: .8rem; padding: 1rem; text-align: left; }
  .production-map .map-core > small { grid-column: 1 / -1; }
  .production-map .map-core .core-ring { grid-row: 2 / 4; width: 3.25rem; height: 3.25rem; margin: .65rem 0 0; }
  .production-map .map-core > b { align-self: end; margin-top: .65rem; }
  .production-map .map-core > p { align-self: start; margin-top: .25rem; }
  .production-map .map-results { grid-row: 3; }
  .production-map .map-card { padding: .72rem .8rem; }
  .production-map .result-card { padding-left: 2.1rem; }
  .hero-proof { grid-template-columns: 1fr; }
  .hero-proof div { min-height: auto; padding: 1rem 1.1rem; }
  .fde-sticky,
  .fde-steps { width: calc(100% - 2rem); }
  .fde-sticky { margin-bottom: 1rem; padding: 1.25rem; }
  .fde-steps { grid-template-columns: 1fr; }
  .fde-step { padding: 1.25rem; }
  .fde-step .fde-output { min-height: auto; }
  .fde-difference div,
  .fde-output { grid-template-columns: 1fr; gap: .35rem; }
  .fde-detail,
  .fde-team,
  .fde-boundary,
  .fde-success { width: calc(100% - 2rem); }
  .fde-detail { grid-template-columns: 1fr; gap: 2rem; margin-top: 4rem; padding-top: 3.5rem; }
  .fde-detail-intro h3 { font-size: 2rem; }
  .fde-responsibilities,
  .fde-boundary-grid { grid-template-columns: 1fr; }
  .fde-responsibilities article,
  .fde-boundary-grid article { min-height: auto; }
  .fde-team { grid-template-columns: 1fr; gap: 2rem; padding: 1.5rem; }
  .fde-team-map { grid-template-columns: 1fr; }
  .team-core { grid-column: 1; grid-template-columns: 3.5rem 1fr; }
  .fde-boundary-head { display: block; }
  .fde-success { grid-template-columns: 1fr; gap: 1.5rem; padding: 1.5rem; }
  .fde-success li { grid-template-columns: 5rem 1fr; }
  .about-layout { grid-template-columns: 1fr; }
  .about-copy .about-lead { font-size: 1rem; }
  .problem-grid { border-bottom: 0; }
  .problem-card,
  .problem-card + .problem-card,
  .problem-card:nth-child(3),
  .problem-card:nth-child(4) { border-left: 0; border-top: 1px solid var(--color-line); }
  .problem-card:first-child { border-top: 0; }
  .solution-tabs,
  .role-buttons { display: flex; overflow-x: auto; scroll-snap-type: x proximity; padding-bottom: .35rem; }
  .solution-tabs button,
  .role-buttons button { flex: 0 0 auto; scroll-snap-align: start; min-height: 3rem; }
  .solution-results { grid-template-columns: 1fr; }
  .solution-results strong { text-align: left; margin-bottom: .5rem; }
  .ai-dev-intro { grid-template-columns: 1fr; }
  .ai-dev-intro p,
  .ai-dev-intro .text-link,
  .ai-dev-intro .ai-dev-links { grid-column: 1; }
  .ai-dev-intro p { margin-top: 1.25rem; }
  .ai-dev-grid,
  .ai-dev-types { grid-template-columns: 1fr; }
  .ai-dev-grid article { min-height: auto; }
  .ai-dev-grid p { min-height: auto; }
  .ai-dev-grid article > span { margin-bottom: 1.5rem; }
  .ai-dev-types div { min-height: auto; }
  .case-kpis div { grid-template-columns: 1fr; gap: .25rem; }
  .faq-list { grid-template-columns: 1fr; }
  .contact-wechat { grid-template-columns: 6.5rem 1fr; }
  .contact-wechat img { width: 6.5rem; height: 6.5rem; }
  .faq-item summary { padding: 1.1rem 3rem 1.1rem 1.15rem; font-size: .95rem; }
  .faq-item p { padding: 0 1.15rem 1.15rem; font-size: .86rem; }
  .form-head { align-items: flex-start; gap: .5rem; }
  .form-head span { max-width: none; text-align: left; }
  .floating-contact { right: 1rem; bottom: 1rem; }
  .floating-contact-trigger { min-height: 3rem; padding: 0 1rem; }
  .floating-contact-panel { max-height: calc(100vh - 6rem); overflow-y: auto; }
  .wechat-contact-card { grid-template-columns: 7.25rem 1fr; gap: .8rem; }
  .wechat-contact-card img { width: 7.25rem; height: 7.25rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}