/* MEILI AI v4 · 单页合并版
   首屏 = v1「昼夜」字体与布局；导航 = 在 v3 c-header 基础上重做（更醒目 + 锚点定位 + 滚动高亮）；
   其后全部区块沿用 v3 模板（tokens / components / home.css）。本文件只追加，不改 v3 任何样式。 */

:root {
  --v4-nav-h: 76px;
  --v4-pad: clamp(22px, 3.4vw, 56px);
  --v4-ease: cubic-bezier(.22, .61, .36, 1);
  --v4-sans: "Inter Tight", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --v4-serif: "Instrument Serif", Georgia, serif;
  --v4-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
}
@media (max-width: 1023px) { :root { --v4-nav-h: 64px; } }
html { scroll-padding-top: calc(var(--v4-nav-h) + 12px); overflow-x: clip; }  /* 兜底：固定导航按 innerWidth 布局时不留横向滚动 */

/* ================================================================
   导航
   ================================================================ */
.v4-nav {
  position: fixed; inset: 0 0 auto 0; z-index: var(--z-header);
  height: var(--v4-nav-h);
  transition: background .45s var(--v4-ease), border-color .45s var(--v4-ease), box-shadow .45s var(--v4-ease);
  border-bottom: 1px solid transparent;
}
.v4-nav.is-stuck {
  background: rgba(5, 7, 12, .78);
  -webkit-backdrop-filter: blur(18px) saturate(1.4); backdrop-filter: blur(18px) saturate(1.4);
  border-bottom-color: var(--line-1);
  box-shadow: 0 12px 40px -24px rgba(0, 0, 0, .8);
}
.v4-nav__inner {
  height: 100%; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: var(--sp-5);
  padding-inline: var(--v4-pad);
}
/* v1 字标 */
.v4-nav__brand { justify-self: start; display: block; opacity: .95; transition: opacity .3s var(--v4-ease); }
.v4-nav__brand:hover { opacity: 1; }
.v4-nav__brand img { display: block; height: 16px; width: auto; }
@media (max-width: 1023px) { .v4-nav__brand img { height: 14px; } }

/* 中间：胶囊导航条 + 滑动高亮块 */
.v4-nav__menu {
  position: relative; display: flex; align-items: center; gap: 2px; padding: 5px;
  border-radius: var(--r-pill);
  background: rgba(255, 255, 255, .045);
  border: 1px solid var(--line-2);
  -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .06);
}
.v4-nav__pill {
  position: absolute; top: 5px; bottom: 5px; left: 0; width: 0; z-index: 0;
  border-radius: var(--r-pill);
  background: linear-gradient(135deg, rgba(28, 33, 136, .9), rgba(10, 92, 180, .9) 60%, rgba(2, 139, 215, .85));
  box-shadow: 0 6px 22px -8px rgba(2, 139, 215, .7), inset 0 1px 0 rgba(255, 255, 255, .18);
  opacity: 0;
  transition: transform .5s var(--v4-ease), width .5s var(--v4-ease), opacity .3s var(--v4-ease);
}
.v4-nav__menu.has-active .v4-nav__pill { opacity: 1; }
.v4-nav__link {
  position: relative; z-index: 1; display: inline-flex; align-items: center; gap: 7px;
  padding: 10px 16px; border-radius: var(--r-pill);
  font: 500 14px/1 var(--font-text); letter-spacing: .02em; color: var(--t2); white-space: nowrap;
  transition: color .3s var(--v4-ease), background .3s var(--v4-ease);
}
.v4-nav__link b { font: 500 10.5px/1 var(--v4-mono); letter-spacing: .06em; color: var(--t4); transition: color .3s var(--v4-ease); }
.v4-nav__link:hover { color: var(--t1); background: rgba(255, 255, 255, .06); }
.v4-nav__link[aria-current="true"] { color: #fff; background: transparent; }
.v4-nav__link[aria-current="true"] b { color: rgba(255, 255, 255, .7); }

.v4-nav__aside { justify-self: end; display: flex; align-items: center; gap: var(--sp-3); }
.v4-nav__cta { min-height: 44px; padding: 0 20px; font-size: 14px; box-shadow: 0 10px 28px -12px rgba(10, 92, 180, .9); }
.v4-nav__cta i { font-style: normal; transition: transform .35s var(--v4-ease); }
.v4-nav__cta:hover i { transform: translateX(3px); }

/* 滚动进度条 */
.v4-nav__progress {
  position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; pointer-events: none;
  background: var(--g-brand); transform-origin: 0 50%; transform: scaleX(var(--p, 0));
  opacity: 0; transition: opacity .3s var(--v4-ease);
}
.v4-nav.is-stuck .v4-nav__progress { opacity: 1; }

/* 移动端 */
.v4-nav__toggle {
  display: none; align-items: center; justify-content: center;
  width: 44px; height: 44px; border-radius: var(--r-pill); color: var(--t1);
  border: 1px solid var(--line-2); background: rgba(255, 255, 255, .04);
}
@media (max-width: 1180px) {
  .v4-nav__link b { display: none; }
  .v4-nav__link { padding: 10px 13px; }
}
@media (max-width: 1023px) {
  /* backdrop-filter 会让 fixed 抽屉相对 header 定位，移动端改实色 */
  .v4-nav.is-stuck, .v4-nav:has(.is-open) { -webkit-backdrop-filter: none; backdrop-filter: none; background: rgba(5, 7, 12, .96); }
  .v4-nav__inner { grid-template-columns: 1fr auto; }
  .v4-nav__toggle { display: inline-flex; }
  .v4-nav__cta { display: none; }
  .v4-nav__menu {
    display: none; position: fixed; inset: var(--v4-nav-h) 0 0 0; z-index: var(--z-drawer);
    flex-direction: column; align-items: stretch; gap: 4px;
    padding: var(--sp-6) var(--gutter) var(--sp-8);
    background: var(--s1); border: 0; border-radius: 0; overflow-y: auto;
    -webkit-backdrop-filter: none; backdrop-filter: none;
  }
  .v4-nav__menu.is-open { display: flex; }
  .v4-nav__pill { display: none; }
  .v4-nav__link { padding: 16px 14px; font-size: var(--fs-h4); border-radius: var(--r-sm); }
  .v4-nav__link b { display: inline; font-size: 12px; }
  .v4-nav__link[aria-current="true"] { background: var(--s2); }
  .v4-nav__menu .v4-nav__cta { display: inline-flex; margin-top: var(--sp-5); }
}
@media (min-width: 1024px) { .v4-nav__menu .v4-nav__cta { display: none; } }

/* ================================================================
   首屏（v1 昼夜 · 字体与布局原样保留）
   ================================================================ */
.v4-hero { position: relative; height: 100vh; height: 100svh; min-height: 800px; overflow: hidden; background: #05060A; color: #EDEFF5; font-family: var(--v4-sans); }
.v4-hero__canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
/* 汇流尽头：官方字标 + 中心辉光。--vp-y 是视觉消失点的纵向位置，画布按字标实际位置对齐 */
.v4-hero { --vp-y: 40%; }
.v4-hero__glow { position: absolute; left: 50%; top: var(--vp-y); width: min(1100px, 92vw); height: min(560px, 56vh); transform: translate(-50%, -50%);
  pointer-events: none; background: radial-gradient(closest-side, rgba(0, 150, 223, .2), rgba(29, 32, 136, .14) 55%, transparent 78%); filter: blur(24px); }
/* 字标本身不加任何 filter：iOS Safari 对带 filter 的 SVG <img> 会低分辨率光栅化或卡在 blur 首帧，导致字发糊。
   辉光改由独立的 .v4-hero__halo 承担，入场与呼吸只动 opacity / transform。 */
.v4-hero__logo { position: absolute; z-index: 4; left: 50%; top: var(--vp-y); width: clamp(132px, 14vw, 230px); height: auto;
  transform: translate(-50%, -50%); pointer-events: none; }
.v4-hero__halo { position: absolute; z-index: 3; left: 50%; top: var(--vp-y); width: clamp(220px, 24vw, 380px); aspect-ratio: 4 / 1;
  transform: translate(-50%, -50%); pointer-events: none; border-radius: 50%;
  background: radial-gradient(closest-side, rgba(0, 150, 223, .32), rgba(29, 32, 136, .12) 60%, transparent); }
.js-motion .v4-hero__logo { animation: v4-logo-in 1.4s .2s var(--v4-ease) both; }
.js-motion .v4-hero__halo { animation: v4-halo-in 1.4s .2s var(--v4-ease) both, v4-halo-breathe 5s 1.8s ease-in-out infinite; }
@keyframes v4-logo-in { from { opacity: 0; transform: translate(-50%, -50%) scale(.94); } }
@keyframes v4-halo-in { from { opacity: 0; } }
@keyframes v4-halo-breathe { 50% { opacity: .55; } }
.v4-hero__scrim { position: absolute; inset: 0 0 auto 0; height: 220px; pointer-events: none;
  background: linear-gradient(180deg, #05060A 0%, rgba(5, 6, 10, .85) 44%, rgba(5, 6, 10, 0) 100%); }
.v4-hero__vignette { position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(120% 90% at 50% var(--vp-y), transparent 45%, rgba(5, 6, 10, .72) 100%); }
/* 底部压暗，保证大标题与点阵重叠处可读 */
.v4-hero__floor { position: absolute; inset: auto 0 0 0; height: 55%; pointer-events: none;
  background: linear-gradient(0deg, rgba(5, 6, 10, .82) 0%, rgba(5, 6, 10, .55) 40%, rgba(5, 6, 10, 0) 100%); }
.v4-hero .mono { font-family: var(--v4-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; font-weight: 400; color: #6E7488; }
.v4-hero__meta { position: absolute; z-index: 3; top: calc(var(--v4-nav-h) + 42px); left: var(--v4-pad); right: var(--v4-pad); display: flex; justify-content: space-between; pointer-events: none; }
.v4-hero__copy { position: absolute; z-index: 3; left: var(--v4-pad); right: var(--v4-pad); bottom: clamp(48px, 7vh, 76px);
  display: grid; grid-template-columns: 1.45fr 1fr; gap: clamp(32px, 5vw, 80px); align-items: end; }
.v4-hero h1 { font-family: var(--v4-sans); font-weight: 300; font-size: clamp(34px, 4.35vw, 68px); line-height: 1.22; letter-spacing: -.035em; color: #F2F4F9; max-width: none; text-wrap: initial; }
.v4-hero h1 em { font-style: normal; font-weight: 400;
  background: linear-gradient(96deg, #0096DF 0%, #4A6BF0 58%, #8C8FFF 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent; }
.v4-hero__aside { max-width: 430px; justify-self: end; padding-bottom: 8px; }
.v4-hero__serif { font-family: var(--v4-serif); font-style: italic; font-size: clamp(20px, 1.8vw, 25px); color: #E9EBF2; line-height: 1.35; margin-bottom: 18px; }
.v4-hero__body { font-size: 14.5px; line-height: 1.9; color: #9BA1B3; max-width: 410px; }
.v4-hero__acts { display: flex; align-items: center; gap: 22px; margin-top: 32px; }
.v4-btn-solid { display: inline-flex; align-items: center; gap: 10px; background: #fff; color: #0B0C12; font-size: 13.5px; font-weight: 500;
  padding: 14px 22px; border-radius: 99px; transition: transform .4s var(--v4-ease), box-shadow .4s var(--v4-ease); }
.v4-btn-solid:hover { color: #0B0C12; transform: translateY(-2px); box-shadow: 0 12px 30px rgba(0, 150, 223, .24); }
.v4-btn-ghost { font-size: 13.5px; color: #C3C8D6; border-bottom: 1px solid rgba(255, 255, 255, .28); padding-bottom: 4px; transition: color .3s, border-color .3s; }
.v4-btn-ghost:hover { color: #fff; border-color: #fff; }
.v4-seam { height: 1px; background: linear-gradient(90deg, #0096DF, #1D2088 42%, rgba(29, 32, 136, 0) 92%); opacity: .85; }

@media (max-width: 1080px) {
  .v4-hero { --vp-y: 32%; }
  .v4-hero__copy { grid-template-columns: 1fr; gap: 26px; }
  .v4-hero__aside { justify-self: start; max-width: none; }
}
@media (max-width: 720px) {
  .v4-hero { min-height: 700px; --vp-y: 28%; }
  .v4-hero__logo { width: min(168px, 44vw); }
  .v4-hero__halo { width: min(240px, 64vw); }
  .v4-hero h1 { font-size: clamp(26px, 7.1vw, 36px); line-height: 1.28; letter-spacing: -.03em; text-wrap: balance; }
  .v4-hero__body { max-width: none; }
  .v4-hero__meta { display: none; }
}
@media (prefers-reduced-motion: reduce) { .v4-hero__logo, .v4-hero__halo, .v4-map__node.is-on .v4-map__ring { animation: none !important; } }

/* ================================================================
   单页化后的小调整
   ================================================================ */
.h-ind__card { cursor: default; }
.v4-contact { display: grid; gap: 6px; margin-top: var(--sp-5); font-size: var(--fs-small); color: var(--t3); }
.v4-contact b { color: var(--t1); font-weight: 600; }
.v4-nav__toggle[aria-expanded="true"] .c-header__burger { background: transparent; }
.v4-nav__toggle[aria-expanded="true"] .c-header__burger::before { transform: translateY(6px) rotate(45deg); }
.v4-nav__toggle[aria-expanded="true"] .c-header__burger::after { transform: translateY(-6px) rotate(-45deg); }

/* ================================================================
   OPC 建设 —— 展示优先：四块各一句话 + 一条极简路径
   ================================================================ */
.v4-opc__grid {
  display: grid; grid-template-columns: 1fr; border-top: 1px solid var(--line-2);
}
.v4-opc__mod {
  display: grid; gap: 8px; padding: clamp(24px, 2.6vw, 34px) 0 clamp(26px, 2.8vw, 36px);
  border-bottom: 1px solid var(--line-1);
}
.v4-opc__modid {
  display: flex; align-items: baseline; gap: 10px;
  font: 500 var(--fs-micro) / 1 var(--font-mono); letter-spacing: .12em; color: var(--t4);
}
.v4-opc__modid span { color: var(--t-accent); }
.v4-opc__mod h3 { font: 600 var(--fs-h4) / 1.35 var(--font-display); letter-spacing: -.015em; color: var(--t1); }
.v4-opc__modlead { font-size: var(--fs-small); line-height: 1.7; color: var(--t3); max-width: 30ch; }

.v4-opc__path {
  display: grid; gap: var(--sp-5); margin-top: clamp(32px, 4vw, 56px);
}
.v4-opc__label { font: 500 11px/1.5 var(--font-mono); letter-spacing: .16em; color: var(--t4); }
.v4-opc__steps {
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0;
  border-top: 1px solid var(--line-1);
}
.v4-opc__steps li {
  display: grid; gap: 6px; padding: 18px 0 20px; border-bottom: 1px solid var(--line-1);
}
.v4-opc__steps li:nth-child(odd) { padding-right: 20px; }
.v4-opc__steps li:nth-child(even) { padding-left: 20px; border-left: 1px solid var(--line-1); }
.v4-opc__when { font: 500 10.5px/1 var(--font-mono); letter-spacing: .12em; color: var(--t-accent); }
.v4-opc__steps b { font: 600 var(--fs-h4) / 1.35 var(--font-display); letter-spacing: -.01em; color: var(--t1); }

@media (min-width: 640px) {
  .v4-opc__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: clamp(20px, 3vw, 40px); }
}
@media (min-width: 1024px) {
  .v4-opc__grid { grid-template-columns: repeat(4, minmax(0, 1fr)); column-gap: clamp(20px, 2.4vw, 36px); }
  /* 桌面：四步一条横线 */
  .v4-opc__steps { grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 0; }
  .v4-opc__steps li {
    position: relative; padding: 22px clamp(12px, 1.6vw, 24px) 0 0; border-bottom: 0;
  }
  .v4-opc__steps li:nth-child(odd) { padding-right: clamp(12px, 1.6vw, 24px); }
  .v4-opc__steps li:nth-child(even) { padding-left: 0; border-left: 0; }
  .v4-opc__steps li::before {
    content: ''; position: absolute; left: 0; right: 0; top: 0; height: 1px;
    background: var(--line-2);
  }
  .v4-opc__steps li:last-child::before { background: linear-gradient(90deg, var(--line-2), transparent); }
  .v4-opc__steps li::after {
    content: ''; position: absolute; left: 0; top: -3px; width: 7px; height: 7px; border-radius: 50%;
    background: var(--t-accent); box-shadow: 0 0 0 4px rgba(56, 182, 242, .1);
  }
  .v4-opc__steps li:last-child::after { background: var(--indigo-lift); box-shadow: 0 0 0 4px rgba(87, 111, 219, .12); }
  .v4-opc__path { grid-template-columns: minmax(120px, 160px) minmax(0, 1fr); align-items: baseline; column-gap: clamp(20px, 3vw, 40px); }
  .v4-opc__label { padding-top: 26px; }
}


/* ====== 页脚：关注我们（二维码）+ 点击放大 ====== */
.c-footer__col.v4-footqr { min-width: 0; }
.v4-footqr__list { display: flex; gap: 8px; }
.v4-footqr__btn {
  display: grid; gap: 6px; padding: 6px 6px 7px; cursor: zoom-in;
  background: #fff; border-radius: 8px; border: 0;
  box-shadow: 0 6px 18px -14px rgba(0, 0, 0, .9);
  transition: transform var(--d-2) var(--e-out), box-shadow var(--d-2) var(--e-out);
}
.v4-footqr__btn:hover { transform: translateY(-2px); box-shadow: 0 12px 24px -14px rgba(0, 0, 0, .9); }
.v4-footqr__btn img { display: block; width: 74px; height: 74px; border-radius: 4px; }
.v4-footqr__btn span { font-size: 10.5px; line-height: 1.3; color: #0B1033; text-align: center; }
@media (min-width: 1024px) {
  .c-footer__inner { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.5fr) auto minmax(0, 1.15fr); column-gap: var(--sp-6); }
}

/* 灯箱 */
.v4-qrbox {
  position: fixed; inset: 0; margin: auto; width: min(92vw, 460px); height: fit-content; max-height: 92vh;
  padding: 0; border: 0; background: transparent; color: var(--t1); overflow: visible;
}
.v4-qrbox::backdrop { background: rgba(3, 5, 10, .82); -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px); }
.v4-qrbox__fig {
  display: grid; gap: 14px; justify-items: center; margin: 0;
  padding: 18px 18px 20px; background: #fff; border-radius: 14px;
  animation: v4-qr-in .28s var(--e-out) both;
}
@keyframes v4-qr-in { from { opacity: 0; transform: scale(.94); } }
.v4-qrbox__fig img { display: block; width: min(78vw, 380px); height: auto; }
.v4-qrbox__fig figcaption { font: 600 var(--fs-small) / 1.4 var(--font-display); color: #0B1033; }
.v4-qrbox__close {
  position: absolute; top: -46px; right: 0; z-index: 1; width: 36px; height: 36px;
  display: grid; place-items: center; border-radius: 50%;
  font-size: 22px; line-height: 1; color: var(--t1);
  background: rgba(255, 255, 255, .1); border: 1px solid var(--line-2); cursor: pointer;
}
.v4-qrbox__close:hover { background: rgba(255, 255, 255, .18); }
@media (prefers-reduced-motion: reduce) { .v4-qrbox__fig { animation: none; } }

/* ====== 布局：城市航图（经纬网 + 点位，不画国界/陆地） ====== */
.v4-map {
  position: relative; display: block; width: 100%; aspect-ratio: 520 / 400;
  border: 1px solid var(--line-1); border-radius: var(--r-md);
  background: radial-gradient(120% 110% at 50% 30%, #0B1226 0%, #060912 62%, #05070C 100%);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .05);
  overflow: hidden;
}
.v4-map__overlay { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.v4-map__arcs path {
  fill: none; stroke: url(#arcFade); stroke-width: 1.6; stroke-linecap: round;
}
.v4-map__ring { fill: none; stroke: rgba(56, 182, 242, .22); stroke-width: 1; transition: stroke .3s var(--e-out); }
.v4-map__core { fill: #7C8AB4; transition: fill .3s var(--e-out), r .3s var(--e-out); }
.v4-map__halo { fill: none; stroke: rgba(56, 182, 242, .16); }
.v4-map__node text { fill: var(--t2); font: 500 14px/1 var(--font-text); letter-spacing: .02em; transition: fill .3s var(--e-out); }
.v4-map__node .net-en { fill: var(--t4); font: 500 8.5px/1 var(--font-mono); letter-spacing: .16em; transition: fill .3s var(--e-out); }
.v4-map__node.is-on .v4-map__core { fill: var(--t-accent); }
.v4-map__node.is-on .v4-map__ring { stroke: rgba(56, 182, 242, .55); animation: v4-map-pulse 3.2s var(--e-out) infinite; transform-origin: center; }
.v4-map__node.is-on text { fill: var(--t1); }
.v4-map__node.is-on .net-en { fill: var(--t3); }
@keyframes v4-map-pulse { 0%, 100% { opacity: .9; } 50% { opacity: .35; } }
.v4-map__hud { fill: var(--t4); font: 500 9.5px/1 var(--font-mono); letter-spacing: .14em; }
.map-axis { fill: var(--t4); font: 500 9px/1 var(--font-mono); letter-spacing: .06em; }
.map-dist { fill: var(--t3); font: 500 9px/1 var(--font-mono); letter-spacing: .08em; }
.map-north { color: var(--t4); fill: var(--t4); font: 600 9px/1 var(--font-mono); }

/* 布局：手机/平板也显示航图（v3 默认在 <1024 隐藏） */
.h-cities__figure { display: block; }
@media (max-width: 767px) {
  .h-cities__figure { margin-bottom: var(--sp-2); }
  .v4-map { max-width: 420px; margin-inline: auto; }
  .v4-map__node .net-label { font-size: 16px; }
  .v4-map__node .net-en { font-size: 9.5px; }
  .v4-map__hud { display: none; }
}
@media (min-width: 768px) and (max-width: 1023px) {
  .h-cities__figure { display: block; }
  .v4-map { max-width: 460px; margin-inline: auto; }
}