/* 群联网络科技官网 V6.0 · 浅色克制版
   零依赖样式表：仅使用 CSS 变量 + Flex/Grid，现代浏览器直接可用。 */

:root {
  --bg: #FBFAF7;
  --surface: #FFFFFF;
  --surface-soft: #F4F7F5;
  --ink: #14201D;
  --body: #5E6B66;
  --muted: #8FA79F;
  --brand: #20B9A1;
  --brand-deep: #0F7A69;
  --brand-bright: #5FE0CB;
  --tint: #EDF7F5;
  --tint-line: #C8E6DF;
  --line: #E4E2DB;
  --dark: #0C1512;
  --dark-card: #14201D;
  --on-dark: #9FB2AB;
  --radius: 18px;
  --radius-sm: 12px;
  --container: 1200px;
  --pad: 120px;

  --font-sans: "Source Han Sans CN", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-serif: "Source Han Serif CN", "Noto Serif CJK SC", "Source Han Serif SC", "Songti SC", STSong, SimSun, serif;
  --font-num: Inter, "SF Pro Text", system-ui, -apple-system, Arial, sans-serif;

  --shadow-card: 0 18px 40px -18px rgba(20, 32, 29, .18), 0 2px 8px rgba(20, 32, 29, .05);
  --shadow-float: 0 14px 34px rgba(20, 32, 29, .16), 0 3px 8px rgba(20, 32, 29, .07);
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { margin: 0; font-family: var(--font-serif); font-weight: 700; letter-spacing: -.4px; }
p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }

.container {
  width: 100%;
  max-width: calc(var(--container) + var(--pad) * 2);
  margin: 0 auto;
  padding: 0 var(--pad);
}

.section { padding: 96px 0; }
.section--tight { padding: 64px 0; }
.section--white { background: var(--surface); }
.section--soft { background: var(--bg); }

.eyebrow {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 1.2px;
  color: var(--brand-deep);
  text-transform: uppercase;
}

.section-title {
  font-size: 38px;
  line-height: 1.4;
  color: var(--ink);
}

.section-lead { font-size: 16px; color: var(--body); line-height: 1.8; max-width: 800px; }

.num { font-family: var(--font-num); font-weight: 700; letter-spacing: 1px; color: var(--brand-deep); }

/* ---------- Header ---------- */
.header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(251, 250, 247, .88);
  backdrop-filter: saturate(140%) blur(12px);
  -webkit-backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.header__inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 76px; gap: 24px;
}
.header__logo img { height: 34px; width: auto; }
.nav { display: flex; align-items: center; gap: 32px; }
.nav a { font-size: 15px; color: var(--body); transition: color .18s ease; }
.nav a:hover { color: var(--ink); }
.header__actions { display: flex; align-items: center; gap: 20px; }

.lang {
  display: inline-flex; align-items: center; height: 32px; padding: 0 14px;
  border: 1px solid var(--line); border-radius: 999px;
  font-family: var(--font-num); font-size: 13px; font-weight: 600; letter-spacing: .6px;
  color: var(--body); transition: all .18s ease;
}
.lang:hover { border-color: var(--brand); color: var(--brand-deep); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 40px; padding: 0 20px; border-radius: 8px;
  font-size: 14px; font-weight: 500; white-space: nowrap;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease, color .18s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn--dark { background: var(--ink); color: #fff; }
.btn--dark:hover { box-shadow: 0 8px 20px -8px rgba(20, 32, 29, .6); }
.btn--lg { height: 52px; padding: 0 28px; font-size: 15px; border-radius: 10px; }
.btn--brand { background: var(--brand); color: var(--dark); font-weight: 700; }
.btn--brand:hover { box-shadow: 0 10px 26px -10px rgba(32, 185, 161, .8); }
.btn--ghost-light {
  background: rgba(255, 255, 255, .10); color: #fff;
  border: 1px solid rgba(255, 255, 255, .45);
}
.btn--ghost-light:hover { background: rgba(255, 255, 255, .18); }
.btn--phone { font-family: var(--font-num); font-weight: 600; letter-spacing: .5px; }

.burger {
  display: none; width: 40px; height: 40px; border: 1px solid var(--line);
  border-radius: 8px; background: var(--surface); cursor: pointer;
  align-items: center; justify-content: center; flex-direction: column; gap: 4px;
}
.burger span { display: block; width: 16px; height: 1.5px; background: var(--ink); }

.mobile-nav { display: none; border-bottom: 1px solid var(--line); background: var(--surface); }
.mobile-nav ul { padding: 8px 24px 20px; }
.mobile-nav a { display: block; padding: 10px 0; font-size: 15px; color: var(--body); }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  min-height: 750px; display: flex; align-items: center;
  background-image: url("../images/hero-workshop.jpg");
  background-size: cover; background-position: left center;
  background-color: var(--dark);
}
.hero__inner { width: 100%; }
.hero__copy { margin-left: auto; width: 560px; max-width: 100%; color: #fff; }
.hero__title { font-size: 46px; line-height: 1.22; letter-spacing: -.5px; color: #fff; }
.hero__sub { margin-top: 24px; font-size: 16px; line-height: 1.8; color: #D3DCD8; }
.hero__cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.hero__trust { display: flex; align-items: center; gap: 8px; margin-top: 24px; color: #D3DCD8; font-size: 14px; }
.hero__trust svg { flex: none; }

/* 首屏 414 号文认证徽章（仅首页 hero 使用） */
.hero__cert {
  display: inline-flex; align-items: center; gap: 9px; flex-wrap: wrap; max-width: 100%;
  padding: 8px 15px; margin-bottom: 16px; border-radius: 999px;
  background: linear-gradient(90deg, rgba(32, 185, 161, .26), rgba(95, 224, 203, .12));
  border: 1px solid rgba(95, 224, 203, .55);
  color: #EAFBF6; font-size: 13px; font-weight: 500; line-height: 1.4;
}
.hero__cert svg { flex: none; }
.hero__cert b { color: var(--brand-bright); font-weight: 700; }

/* ---------- Proof ---------- */
.proof { background: var(--surface); }
.proof__grid { display: flex; gap: 56px; align-items: center; }
.metrics, .metric__row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; flex: 1 1 auto; }
.metrics { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; flex: 1 1 auto; }
.metric { padding-left: 20px; }
.metric:first-child { padding-left: 0; }
.metric__num { font-family: var(--font-serif); font-weight: 700; font-size: 34px; line-height: 1.2; white-space: nowrap; }
.metric__label { font-size: 13px; color: var(--muted); line-height: 1.6; }

.qr-card {
  display: flex; align-items: center; gap: 18px; flex: 0 1 340px; min-width: 0; max-width: 100%;
  padding: 22px; border: 1px solid var(--line); border-radius: 16px; background: var(--bg);
}
.qr-card img { width: 96px; height: 96px; border-radius: 8px; flex: none; }
.qr-card__title { font-family: var(--font-sans); font-weight: 700; font-size: 16px; color: var(--ink); }
.qr-card__body { font-size: 13px; color: var(--body); line-height: 1.6; }

/* ---------- Client wall ---------- */
.clients { text-align: center; }
.clients__label { font-size: 13px; letter-spacing: 1.5px; color: var(--muted); margin-bottom: 24px; }
.clients__wall { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.tag {
  display: inline-flex; align-items: center; height: 38px; padding: 0 16px;
  border: 1px solid var(--line); border-radius: 999px; background: var(--surface);
  font-size: 13px; color: var(--body);
}
.tag--brand { background: var(--tint); border-color: var(--tint-line); color: var(--brand-deep); }

/* ---------- Business lines ---------- */
.biz__row { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.card {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px;
}
.card--tint { background: var(--tint); border-color: var(--tint-line); }
.card--accent { background: var(--tint); border-color: var(--tint-line); }
.card__visual { width: 100%; height: auto; border-radius: var(--radius-sm); }
.card__title-row { display: flex; align-items: center; gap: 12px; margin-top: 18px; }
.card__title { font-size: 26px; }
.card__desc { margin-top: 12px; font-size: 14px; line-height: 1.75; color: var(--body); }
.card__desc--strong { color: var(--brand-deep); }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.tag--sm { height: 34px; padding: 0 14px; background: var(--bg); }

.banner {
  display: flex; align-items: center; gap: 36px; margin-top: 24px;
  background: var(--tint); border-radius: var(--radius); padding: 36px;
}
.banner__title { margin-top: 10px; font-size: 26px; line-height: 1.45; }
.banner__desc { margin-top: 10px; font-size: 14px; line-height: 1.75; color: var(--brand-deep); }
.banner__note { margin-top: 14px; padding-top: 14px; border-top: 1px solid var(--tint-line); font-size: 13px; line-height: 1.7; color: #43514C; }
.banner__visual { width: 220px; flex: none; border-radius: var(--radius-sm); }

/* ---------- Capability grid ---------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.item { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 24px; }
.item__icon { width: 36px; height: 36px; margin-bottom: 12px; }
.item__title { font-family: var(--font-sans); font-weight: 700; font-size: 17px; }
.item__desc { margin-top: 8px; font-size: 13px; line-height: 1.7; color: var(--muted); }

/* 能力浏览器 Capability explorer —— 服务卡片切换图文详情 */
.svc-explorer { margin-top: 40px; display: grid; grid-template-columns: 336px 1fr; gap: 26px; align-items: stretch; }
.svc-tabs { display: flex; flex-direction: column; gap: 8px; }
.svc-tab {
  display: flex; align-items: center; gap: 12px; width: 100%; text-align: left;
  padding: 13px 15px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface);
  cursor: pointer; font: inherit; color: var(--ink); transition: border-color .2s, background .2s, box-shadow .2s;
}
.svc-tab__i { width: 26px; height: 26px; flex: none; }
.svc-tab__t { font-weight: 600; font-size: 15px; line-height: 1.35; }
.svc-tab:hover { border-color: var(--tint-line); background: var(--tint); }
.svc-tab.is-active { border-color: var(--brand); background: var(--tint); box-shadow: inset 3px 0 0 var(--brand); }
.svc-tab.is-active .svc-tab__t { color: var(--brand-deep); }
.svc-panels { min-width: 0; display: flex; }
.svc-panel { display: none; }
.svc-panel.is-active { display: grid; flex: 1; grid-template-columns: 1.02fr 1.1fr; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: var(--surface); box-shadow: var(--shadow-card); animation: svcFade .3s ease; }
@keyframes svcFade { from { opacity: .35; } to { opacity: 1; } }
.svc-panel.is-active .svc-panel__img { animation: svcImg .65s cubic-bezier(.16,1,.3,1) both; }
@keyframes svcImg { from { transform: scale(1.07); opacity: .5; } to { transform: scale(1); opacity: 1; } }
.svc-panel.is-active .svc-panel__body > * { animation: svcUp .5s cubic-bezier(.16,1,.3,1) both; }
.svc-panel.is-active .svc-panel__body > *:nth-child(1) { animation-delay: .06s; }
.svc-panel.is-active .svc-panel__body > *:nth-child(2) { animation-delay: .12s; }
.svc-panel.is-active .svc-panel__body > *:nth-child(3) { animation-delay: .18s; }
.svc-panel.is-active .svc-panel__body > *:nth-child(4) { animation-delay: .24s; }
.svc-panel.is-active .svc-panel__body > *:nth-child(5) { animation-delay: .30s; }
@keyframes svcUp { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }
.svc-panel__img { width: 100%; height: 100%; min-height: 300px; object-fit: cover; object-position: center; background: var(--bg); display: block; }
.svc-panel__body { padding: 30px 32px; display: flex; flex-direction: column; justify-content: center; }
@media (prefers-reduced-motion: reduce) {
  .svc-panel.is-active, .svc-panel.is-active .svc-panel__img, .svc-panel.is-active .svc-panel__body > * { animation: none !important; }
}
.svc-panel__tag { font-size: 12.5px; letter-spacing: .3px; color: var(--brand-deep); font-weight: 600; }
.svc-panel__title { font-family: var(--font-serif); font-weight: 700; font-size: 23px; color: var(--ink); margin-top: 6px; }
.svc-panel__lead { margin-top: 12px; font-size: 14.5px; line-height: 1.85; color: var(--body); }
.svc-panel__list { margin-top: 16px; display: grid; gap: 9px; }
.svc-panel__list li { position: relative; padding-left: 26px; font-size: 13.5px; color: var(--ink); line-height: 1.55; list-style: none; }
.svc-panel__list li::before { content: ""; position: absolute; left: 0; top: 2px; width: 16px; height: 16px; border-radius: 50%; background: var(--tint); border: 1.5px solid var(--brand); }
.svc-panel__list li::after { content: ""; position: absolute; left: 5px; top: 6px; width: 7px; height: 4px; border-left: 1.8px solid var(--brand-deep); border-bottom: 1.8px solid var(--brand-deep); transform: rotate(-45deg); }
.svc-panel__chips { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 7px; }
.svc-panel__chips span { font-size: 12px; color: var(--brand-deep); background: var(--tint); border: 1px solid var(--tint-line); border-radius: 999px; padding: 3px 11px; }
@media (max-width: 1080px) { .svc-explorer { grid-template-columns: 280px 1fr; } }
@media (max-width: 900px) {
  .svc-explorer { grid-template-columns: 1fr; gap: 16px; }
  .svc-tabs { flex-direction: row; overflow-x: auto; padding-bottom: 6px; -webkit-overflow-scrolling: touch; scrollbar-width: none; }
  .svc-tabs::-webkit-scrollbar { display: none; }
  .svc-tab { width: auto; flex: none; }
  .svc-tab.is-active { box-shadow: inset 0 -3px 0 var(--brand); }
  .svc-panel.is-active { grid-template-columns: 1fr; }
  .svc-panel__img { min-height: 0; max-height: 210px; }
  .svc-panel__body { padding: 22px 20px 24px; justify-content: flex-start; }
}

/* ---------- Process ---------- */
.process { background: var(--surface); }
.diamond {
  position: relative; margin-top: 44px; padding: 30px 26px 26px;
  border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
  background: radial-gradient(130% 130% at 50% 0%, var(--surface) 0%, var(--bg) 62%);
}
.diamond svg { display: block; width: 100%; height: auto; }
.diamond__labels { position: absolute; inset: 30px 26px 26px; pointer-events: none; }
.diamond__phase {
  position: absolute; top: 50%; transform: translate(-50%, -50%);
  text-align: center; line-height: 1.25; white-space: nowrap;
}
.diamond__phase b { display: block; font-family: var(--font-serif); font-weight: 700; font-size: 19px; color: var(--ink); }
.diamond__phase .dd-en { display: block; font-family: var(--font-num); font-size: 12px; letter-spacing: .4px; color: var(--muted); }
.diamond__phase em { display: inline-block; margin-top: 5px; font-style: normal; font-size: 11px; font-weight: 500; padding: 1px 9px; border-radius: 999px; }
.diamond__phase em.dv { background: rgba(32, 185, 161, .14); color: var(--brand-deep); }
.diamond__phase em.cv { background: rgba(15, 122, 105, .14); color: var(--brand-deep); }
.diamond__phase--1 { left: 20.7%; }
.diamond__phase--2 { left: 40.2%; }
.diamond__phase--3 { left: 59.8%; }
.diamond__phase--4 { left: 79.3%; }
.diamond__pivot {
  position: absolute; left: 50%; top: 19.4%; transform: translate(-50%, -50%);
  text-align: center; line-height: 1.3; white-space: nowrap;
  font-family: var(--font-serif); font-weight: 700; font-size: 15px; color: var(--brand-deep);
  background: var(--surface); border: 1px solid var(--tint-line); border-radius: 999px;
  padding: 7px 15px; box-shadow: var(--shadow-float);
}
.diamond__pivot span { display: block; font-family: var(--font-num); font-weight: 400; font-size: 11px; letter-spacing: .4px; color: var(--muted); }
.diamond__space {
  position: absolute; bottom: 0; transform: translateX(-50%);
  font-size: 12.5px; color: var(--body); white-space: nowrap; letter-spacing: .2px;
}
.diamond__space b { color: var(--ink); font-weight: 700; }
.diamond__space--a { left: 30.5%; }
.diamond__space--b { left: 69.5%; }

/* 双钻动效：滚动进入时两钻依次描边生长→填充→拐点落定 */
.dd-axis { stroke-dasharray: 1; stroke-dashoffset: 1; transition: stroke-dashoffset .65s cubic-bezier(0.16, 1, 0.3, 1); }
.dd-diamond { stroke-dasharray: 1; stroke-dashoffset: 1; fill-opacity: 0; }
.dd-diamond--1 { transition: stroke-dashoffset 1s cubic-bezier(0.16, 1, 0.3, 1) .15s, fill-opacity .7s ease 1s; }
.dd-diamond--2 { transition: stroke-dashoffset 1s cubic-bezier(0.16, 1, 0.3, 1) .7s, fill-opacity .7s ease 1.45s; }
.dd-dot { opacity: 0; transition: opacity .45s ease; }
.diamond__labels { opacity: 0; transition: opacity .5s ease .35s; }
.diamond__phase { pointer-events: auto; cursor: help; }
.diamond__pivot { opacity: 0; transform: translate(-50%, -50%) scale(.9); transition: opacity .45s ease 1.5s, transform .45s ease 1.5s; }
.diamond.is-in .dd-axis { stroke-dashoffset: 0; }
.diamond.is-in .dd-diamond { stroke-dashoffset: 0; fill-opacity: 1; }
.diamond.is-in .dd-dot { opacity: 1; transition-delay: 1.15s; }
.diamond.is-in .dd-dot--soft { opacity: .6; }
.diamond.is-in .diamond__labels { opacity: 1; }
.diamond.is-in .diamond__pivot { opacity: 1; transform: translate(-50%, -50%) scale(1); }

.diamond__hint { margin: 14px auto 0; text-align: center; font-size: 13px; color: var(--body); letter-spacing: .2px; }

/* 阶段常用方法提示（悬停 / 键盘聚焦） */
.dd-tip {
  position: absolute; top: calc(100% + 12px); left: 50%; transform: translateX(-50%) translateY(5px);
  width: max-content; max-width: 232px; white-space: normal; text-align: center;
  font-family: var(--font-sans); font-size: 12.5px; font-weight: 400; line-height: 1.65; letter-spacing: 0;
  color: var(--body); background: var(--surface); border: 1px solid var(--tint-line);
  border-radius: 12px; padding: 10px 14px; box-shadow: var(--shadow-float);
  opacity: 0; visibility: hidden; pointer-events: none; z-index: 6;
  transition: opacity .22s ease, transform .22s ease, visibility .22s;
}
.dd-tip i { display: block; margin-bottom: 4px; font-style: normal; font-family: var(--font-serif); font-weight: 700; font-size: 13px; color: var(--ink); }
.dd-tip::before { content: ""; position: absolute; bottom: 100%; left: 50%; transform: translateX(-50%); border: 7px solid transparent; border-bottom-color: var(--tint-line); }
.dd-tip::after { content: ""; position: absolute; bottom: 100%; left: 50%; transform: translateX(-50%); border: 6px solid transparent; border-bottom-color: var(--surface); margin-bottom: -1px; }
.diamond__phase:hover .dd-tip, .diamond__phase:focus .dd-tip { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.diamond__phase:focus-visible { outline: 2px solid var(--brand-deep); outline-offset: 4px; border-radius: 6px; }

@media (prefers-reduced-motion: reduce) {
  .dd-axis, .dd-diamond { stroke-dashoffset: 0 !important; transition: none !important; }
  .dd-diamond { fill-opacity: 1 !important; }
  .dd-dot { opacity: 1 !important; transition: none !important; }
  .dd-dot--soft { opacity: .6 !important; }
  .diamond__labels { opacity: 1 !important; transition: none !important; }
  .diamond__pivot { opacity: 1 !important; transform: translate(-50%, -50%) !important; transition: none !important; }
}

.steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; margin-top: 24px; }
.step { border: 1px solid var(--line); border-radius: 14px; background: var(--bg); padding: 20px; }
.step--accent { background: var(--tint); border-color: var(--tint-line); }
.step__title { font-family: var(--font-sans); font-weight: 700; font-size: 17px; }
.step__desc { margin-top: 8px; font-size: 13px; line-height: 1.65; color: var(--muted); }
.step--accent .step__desc { color: var(--brand-deep); }

/* ---------- Case ---------- */
.case-card {
  display: grid; grid-template-columns: 520px 1fr; margin-top: 44px;
  background: var(--surface); border: 1px solid var(--line); border-radius: 20px;
  overflow: hidden; box-shadow: var(--shadow-card);
}
.case-card__photo { width: 100%; height: 100%; object-fit: cover; object-position: left center; min-height: 420px; }
.case-card__copy { padding: 40px; display: flex; flex-direction: column; gap: 16px; }
.case-card__title { font-size: 28px; line-height: 1.4; }
.case-card__desc { font-size: 15px; line-height: 1.8; color: var(--body); }
.case-metrics { display: flex; gap: 32px; }
.case-metric__num { font-family: var(--font-serif); font-weight: 700; font-size: 30px; color: var(--brand-deep); line-height: 1.2; }
.case-metric__label { font-size: 13px; color: var(--muted); }
.case-note { display: flex; align-items: center; gap: 8px; font-size: 13px; color: #43514C; }

.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 24px; }
.group { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 24px; }
.group__title { font-family: var(--font-sans); font-weight: 700; font-size: 16px; }
.group__names { margin-top: 10px; font-size: 13px; line-height: 1.75; color: var(--body); }
.group__dir { margin-top: 10px; font-size: 12px; line-height: 1.6; color: var(--muted); }

/* ---------- Case gallery grid ---------- */
.case-grid__label { margin-top: 44px; font-family: var(--font-sans); font-weight: 700; font-size: 15px; color: var(--muted); letter-spacing: .3px; }
.case-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 16px; }
.case-tile { margin: 0; background: var(--surface); border: 1px solid var(--line); border-radius: 14px; overflow: hidden; transition: transform .18s ease, box-shadow .18s ease; }
.case-tile:hover { transform: translateY(-3px); box-shadow: var(--shadow-float); }
.case-tile img { width: 100%; height: auto; aspect-ratio: 16 / 9; object-fit: cover; object-position: left top; display: block; border-bottom: 1px solid var(--line); }
.case-tile figcaption { padding: 14px 16px; display: flex; flex-direction: column; gap: 3px; }
.case-tile figcaption strong { font-family: var(--font-sans); font-weight: 700; font-size: 15px; color: var(--ink); }
.case-tile figcaption span { font-size: 12.5px; line-height: 1.55; color: var(--muted); }

/* ---------- Founder ---------- */
.founder { background: var(--surface); }
.founder__grid { display: grid; grid-template-columns: 440px 1fr; gap: 56px; align-items: center; }
.founder__photo { width: 100%; height: 420px; object-fit: cover; border-radius: 20px; }
.founder__name { margin-top: 16px; font-size: 34px; line-height: 1.35; }
.founder__role { font-size: 15px; font-weight: 500; color: var(--muted); }
.founder__bio { margin-top: 16px; font-size: 15px; line-height: 1.8; color: var(--body); }

/* ---------- FAQ ---------- */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; margin-top: 40px; }
.faq { background: var(--bg); border: 1px solid var(--line); border-radius: 14px; padding: 24px 28px; }
.faq__q { font-family: var(--font-sans); font-weight: 700; font-size: 17px; }
.faq__a { margin-top: 8px; font-size: 14px; line-height: 1.7; color: var(--body); }

/* ---------- Final CTA ---------- */
.cta { background: var(--dark-card); padding: 88px 0; }
.cta__grid { display: grid; grid-template-columns: 1fr auto; gap: 64px; align-items: center; }
.cta__title { font-size: 40px; line-height: 1.45; color: #fff; }
.cta__sub { margin-top: 18px; font-size: 16px; color: var(--on-dark); }
.cta__buttons { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.cta__qr { width: 220px; padding: 20px; border-radius: 16px; background: #fff; text-align: center; }
.cta__qr img { width: 100%; height: auto; aspect-ratio: 1 / 1; object-fit: contain; border-radius: 8px; }
.cta__qr span { display: block; margin-top: 12px; font-size: 13px; font-weight: 500; color: var(--ink); }

/* ---------- Footer ---------- */
.footer { background: var(--dark); padding: 48px 0 40px; }
.footer__top { display: flex; flex-wrap: wrap; gap: 40px; justify-content: space-between; }
.footer__logo { height: 38px; width: auto; }
.footer__tag { margin-top: 14px; font-size: 14px; line-height: 1.65; color: var(--muted); max-width: 420px; }
.footer__contact { display: flex; flex-direction: column; gap: 8px; font-size: 14px; }
.footer__contact strong { font-weight: 500; color: #fff; }
.footer__contact span { color: var(--muted); }
.footer__contact a { color: var(--muted); }
.footer__contact a:hover { color: var(--brand-bright); }
.footer__rule { height: 1px; background: #1A2A26; margin: 28px 0 0; }
.footer__copy { margin-top: 20px; font-family: var(--font-num); font-size: 12px; letter-spacing: .3px; color: var(--body); }
/* ICP 备案号：法定必需项，每页页脚都要可见，故对比度高于版权行 */
.footer__beian { margin-top: 8px; font-family: var(--font-num); font-size: 12px; letter-spacing: .3px; }
.footer__beian a { color: var(--muted); text-decoration: none; transition: color .2s ease; }
.footer__beian a:hover { color: var(--brand-bright); text-decoration: underline; }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ---------- Responsive ---------- */
@media (max-width: 1180px) {
  :root { --pad: 64px; }
  .hero__copy { width: 520px; }
  .biz__row, .grid-3, .grid-4, .founder__grid, .cta__grid { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: repeat(2, 1fr); }
  .founder__photo { height: 320px; }
  .cta__grid { gap: 40px; }
  .qr-card { width: 100%; }
}

@media (max-width: 900px) {
  :root { --pad: 24px; }
  .nav, .header__actions .lang { display: none; }
  .burger { display: inline-flex; }
  .mobile-nav.is-open { display: block; }
  .section { padding: 64px 0; }
  .hero { min-height: 640px; }
  .hero__inner { padding: 96px var(--pad) 72px; }
  .hero__copy { margin-left: 0; width: 100%; }
  .hero__title { font-size: 34px; }
  .hero__cert { display: block; border-radius: 18px; line-height: 1.6; }
  .hero__cert svg { vertical-align: -3px; }
  .proof__grid, .metrics { display: block; }
  .metric { padding-left: 0; margin-bottom: 24px; }
  .metric__row { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .grid-2, .grid-3, .grid-4, .steps { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: 1fr 1fr; }
  .case-card { grid-template-columns: 1fr; }
  .case-card__photo { min-height: 240px; height: 240px; }
  .card__visual { display: block; }
  .banner { flex-direction: column; align-items: flex-start; }
  .banner__visual { width: 100%; max-width: 320px; }
  .section-title { font-size: 28px; }
  .cta__title { font-size: 28px; }
  .diamond { padding: 16px 12px 14px; }
  .diamond__labels { inset: 16px 12px 14px; }
  .diamond__phase b { font-size: 13px; }
  .diamond__phase .dd-en, .diamond__phase em, .dd-tip { display: none; }
  .diamond__hint { display: none; }
  .diamond__phase { cursor: default; }
  .diamond__space { display: none; }
  .diamond__pivot { font-size: 12px; padding: 4px 10px; }
  .diamond__pivot span { display: none; }
  .footer__top { flex-direction: column; }
}

@media (max-width: 640px) {
  .hero { min-height: 560px; }
  .hero__title { font-size: 27px; }
  .hero__cta .btn { width: 100%; }
  .btn--lg { width: 100%; }
  .cta__qr { width: 100%; }
  .case-grid { grid-template-columns: 1fr; }
}

/* =========================================================
   Inner pages (V6.0 multi-page)
   ========================================================= */

/* Page hero (light banner for sub-pages) */
.page-hero { background: var(--tint); border-bottom: 1px solid var(--tint-line); padding: 56px 0 48px; }
.page-hero--dark { background: var(--dark-card); border-bottom: none; }
.breadcrumb { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-size: 13px; color: var(--muted); margin-bottom: 18px; }
.breadcrumb a { color: var(--brand-deep); }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb span[aria-current] { color: var(--body); }
.page-hero__title { font-size: 40px; line-height: 1.3; color: var(--ink); }
.page-hero--dark .page-hero__title { color: #fff; }
.page-hero__sub { margin-top: 16px; font-size: 16px; line-height: 1.8; color: var(--body); max-width: 760px; }
.page-hero--dark .page-hero__sub { color: #D3DCD8; }
.page-hero__eyebrow { font-size: 12px; font-weight: 500; letter-spacing: 1.2px; text-transform: uppercase; color: var(--brand-deep); margin-bottom: 12px; }

/* Service sub-nav strip */
.subnav { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 26px; }
.subnav a { display: inline-flex; align-items: center; height: 38px; padding: 0 16px; border: 1px solid var(--tint-line); border-radius: 999px; background: var(--surface); font-size: 14px; color: var(--body); transition: all .18s ease; }
.subnav a:hover { border-color: var(--brand); color: var(--brand-deep); }
.subnav a.is-active { background: var(--brand-deep); border-color: var(--brand-deep); color: #fff; }

/* Article / prose body */
.prose { max-width: 820px; }
.prose--wide { max-width: 960px; }
.prose h2 { font-size: 26px; line-height: 1.4; margin-top: 40px; }
.prose h3 { font-family: var(--font-sans); font-weight: 700; font-size: 19px; margin-top: 30px; }
.prose p { margin-top: 14px; font-size: 15.5px; line-height: 1.85; color: var(--body); }
.prose ul.bul { margin-top: 14px; display: grid; gap: 10px; }
.prose ul.bul li { position: relative; padding-left: 22px; font-size: 15px; line-height: 1.75; color: var(--body); }
.prose ul.bul li::before { content: ""; position: absolute; left: 0; top: 10px; width: 8px; height: 8px; border-radius: 50%; background: var(--brand); }
.prose strong { color: var(--ink); font-weight: 600; }
.prose a { color: var(--brand-deep); text-decoration: underline; text-underline-offset: 2px; }

/* Case detail layout */
.case-hero-media { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; object-position: left top; border-radius: var(--radius); border: 1px solid var(--line); margin-top: 8px; }
.kv { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 8px; }
.kv__cell { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 20px 22px; }
.kv__k { font-size: 12px; letter-spacing: .6px; text-transform: uppercase; color: var(--muted); }
.kv__v { margin-top: 6px; font-size: 15px; line-height: 1.6; color: var(--ink); font-weight: 500; }
.block { margin-top: 40px; }
.block__label { font-size: 12px; font-weight: 600; letter-spacing: 1px; text-transform: uppercase; color: var(--brand-deep); }
.block__title { font-size: 24px; margin-top: 8px; }
.result-strip { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 18px; }
.result { background: var(--tint); border: 1px solid var(--tint-line); border-radius: 14px; padding: 22px; }
.result__num { font-family: var(--font-serif); font-weight: 700; font-size: 30px; color: var(--brand-deep); line-height: 1.15; }
.result__label { margin-top: 6px; font-size: 13px; color: var(--body); line-height: 1.55; }

/* Link cards (homepage → sub-pages) */
.link-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.link-card { display: flex; flex-direction: column; gap: 8px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; transition: transform .18s ease, box-shadow .18s ease; }
.link-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-float); border-color: var(--tint-line); }
.link-card__title { font-size: 20px; }
.link-card__desc { font-size: 14px; line-height: 1.7; color: var(--body); }
.link-card__more { margin-top: auto; padding-top: 10px; font-size: 14px; font-weight: 600; color: var(--brand-deep); }
.link-card__more::after { content: " →"; }

/* Pricing hook */
.price-hook { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 20px; background: var(--dark-card); border-radius: var(--radius); padding: 28px 32px; margin-top: 24px; }
.price-hook__lead { color: #fff; font-family: var(--font-serif); font-weight: 700; font-size: 22px; line-height: 1.4; }
.price-hook__lead b { color: var(--brand-bright); }
.price-hook__note { color: var(--on-dark); font-size: 13px; margin-top: 6px; }
.price-hook .btn { flex: none; }

/* Contact form */
.form { display: grid; gap: 16px; margin-top: 8px; }
.form__row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field label { font-size: 13px; font-weight: 600; color: var(--ink); }
.field input, .field textarea, .field select { font-family: inherit; font-size: 15px; color: var(--ink); background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px; }
.field input:focus, .field textarea:focus, .field select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px rgba(32,185,161,.15); }
.field textarea { resize: vertical; min-height: 110px; }
.form__hint { font-size: 13px; color: var(--muted); }

/* Prev/next case nav */
.pn { display: flex; justify-content: space-between; gap: 16px; margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--line); }
.pn a { display: flex; flex-direction: column; gap: 4px; font-size: 14px; color: var(--body); }
.pn a:hover { color: var(--brand-deep); }
.pn a .pn__k { font-size: 12px; letter-spacing: .6px; text-transform: uppercase; color: var(--muted); }
.pn a.next { text-align: right; }

/* Site map in footer */
.footer__cols { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 32px; }
.footer__col h4 { font-family: var(--font-sans); font-weight: 600; font-size: 13px; letter-spacing: .6px; text-transform: uppercase; color: var(--muted); margin-bottom: 12px; }
.footer__col a { display: block; padding: 5px 0; font-size: 14px; color: var(--on-dark); }
.footer__col a:hover { color: var(--brand-bright); }

/* Inner-page responsive */
@media (max-width: 900px) {
  .page-hero__title { font-size: 30px; }
  .kv, .result-strip, .link-cards { grid-template-columns: 1fr; }
  .form__row { grid-template-columns: 1fr; }
  .footer__cols { grid-template-columns: 1fr 1fr; }
  .price-hook { flex-direction: column; align-items: flex-start; }
  .price-hook .btn { width: 100%; }
}

/* ============================================================
   开屏动画 Splash —— 仅首页（index.html / index-en.html）引用该图层。
   三重保险、绝不死锁：
     1) 容器自身纯 CSS 动画 0.9s 后淡出并 visibility:hidden（无 JS 也能揭示页面）
     2) JS 监听点击可提前跳过、并在动画后移除节点（见 main.js）
     3) prefers-reduced-motion 直接不渲染
   ============================================================ */
#splash-screen {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: var(--dark);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: splashExit 0.9s ease-in forwards;
}
#splash-logo {
  animation: splashZoom 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
@keyframes splashZoom {
  0% { transform: scale(1); opacity: 1; }
  65% { transform: scale(6); opacity: 0.5; }
  100% { transform: scale(14); opacity: 0; }
}
@keyframes splashExit {
  0%, 78% { opacity: 1; }
  100% { opacity: 0; visibility: hidden; pointer-events: none; }
}
@media (prefers-reduced-motion: reduce) {
  #splash-screen { display: none; }
}

/* ============================================================
   设计精修 Design refinements —— impeccable pass
   仅调层级/对比/留白/原生表面，不改内容与品牌识别。
   ============================================================ */

/* 1) 小字对比度：浅色背景上的三级文字统一提到 --body（对白底 ≥ 5:1），
      --muted 仅保留于深色页脚等真正次要处。 */
.metric__label, .item__desc, .step__desc, .group__dir,
.case-tile figcaption span, .founder__role, .diamond__label span,
.diamond__sub, .clients__label, .kv__k, .pn a .pn__k, .form__hint,
.breadcrumb { color: var(--body); }

/* 2) 浏览器原生表面：选中、焦点、滚动条、光标全部取自品牌色，
      这是“页面被精心构建过”最廉价、最常被忽略的信号。 */
::selection { background: rgba(32, 185, 161, .22); color: var(--ink); }
:focus-visible { outline: 2px solid var(--brand-deep); outline-offset: 2px; border-radius: 5px; }
body { caret-color: var(--brand-deep); }
html { scrollbar-color: var(--tint-line) transparent; scrollbar-width: thin; }
::-webkit-scrollbar { width: 12px; height: 12px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--tint-line); border: 3px solid var(--bg); border-radius: 999px; }
::-webkit-scrollbar-thumb:hover { background: var(--brand); }

/* 3) 首屏：认证徽章与标题间留更充分的呼吸（上方留白 > 下方）。 */
.hero__cert { margin-bottom: 22px; }

/* 4) GEO 配图：放大到可读尺寸，裁掉图内底部空白，成框为“AI 答案卡”。 */
.banner__visual {
  width: 360px; height: 140px; object-fit: cover; object-position: top center;
  background: #fff; border-radius: 14px;
  border: 1px solid var(--tint-line); box-shadow: var(--shadow-card);
}

/* 5) 联系页“直接联系”卡：左信息右二维码，电话/邮箱/日期一律不断行。 */
.case-card--contact { grid-template-columns: 1fr 300px; }
.case-card--contact .kv { grid-template-columns: 1.15fr 1.15fr .7fr; gap: 14px; }
.case-card--contact .kv__k,
.case-card--contact .kv__v { white-space: nowrap; }
.case-card--contact .cta__qr { width: 100%; }

@media (max-width: 900px) {
  .banner__visual { width: 100%; max-width: 360px; height: 150px; }
  .case-card--contact { grid-template-columns: 1fr; }
  .case-card--contact .kv { grid-template-columns: 1fr; }
  .case-card--contact .kv__k,
  .case-card--contact .kv__v { white-space: normal; }
}