/* =========================================================
   云时代安卓站 · 共享样式表 /assets/site.css
   蓝图网格 × 云层曲线｜天青蓝 / 云白 / 生机绿
   ========================================================= */

/* ---------- 01 Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0}
h1,h2,h3,h4,h5,p,figure,blockquote,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg,video{display:block;max-width:100%;height:auto}
button,input,select,textarea{font:inherit;color:inherit}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:2px solid var(--green);outline-offset:2px}

/* ---------- 02 Tokens ---------- */
:root{
  --sky:#3A7CA5;
  --sky-deep:#28607F;
  --cloud:#F7F9FC;
  --paper:#F2E9DC;
  --green:#3DDC84;
  --ink:#1F2A36;
  --ink-brown:#2B211B;
  --flame:#E4572E;
  --grid:#A9C4D6;
  --mist:#D8E3EC;
  --cream:#FDFBF6;
  --ink-soft:#4E5F6E;
  --ink-mute:#7C8B98;
  --on-dark:#DCE6EF;
  --on-dark-soft:#9FB3C2;

  --font-sans:"Noto Sans SC","Source Han Sans SC","思源黑体","PingFang SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono","Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --font-serif:"Noto Serif SC","Source Han Serif SC","思源宋体",Georgia,serif;

  --header-h:64px;
  --gutter:20px;
  --wrap:1280px;
  --cell:48px;
  --radius:14px;
  --radius-organic:16px 16px 16px 4px;
  --shadow:0 10px 30px rgba(31,42,54,.08);
  --ease:.2s ease;
}
@media (min-width:768px){:root{--gutter:32px;--header-h:72px}}
@media (min-width:1024px){:root{--header-h:80px}}
@media (min-width:1280px){:root{--gutter:48px}}

/* ---------- 03 Base typography ---------- */
body{
  background:var(--cloud);
  color:var(--ink);
  font-family:var(--font-sans);
  font-size:17px;
  font-weight:400;
  line-height:1.8;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4{font-weight:800;letter-spacing:-.02em;line-height:1.15;color:var(--ink-brown)}
h1{font-size:clamp(32px,4.6vw,52px)}
h2{font-size:clamp(26px,3.4vw,40px)}
h3{font-size:clamp(20px,2.2vw,26px)}
h4{font-size:20px}
strong,b{font-weight:700;color:var(--ink-brown)}
small{font-size:13px}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:0}
.sr-only{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}

/* ---------- 04 Layout ---------- */
.wrap{
  width:min(calc(100% - 2 * var(--gutter)),var(--wrap));
  margin-inline:auto;
}
main{padding-top:var(--header-h)}
.under-header{margin-top:calc(var(--header-h) * -1)}

.grid{display:grid;gap:clamp(20px,3vw,40px);grid-template-columns:1fr}
@media (min-width:900px){
  .grid--5-7{grid-template-columns:5fr 7fr}
  .grid--4-8{grid-template-columns:4fr 8fr}
}

.bp-section{
  position:relative;
  padding:clamp(56px,7vw,110px) 0;
  background-color:var(--cloud);
  background-image:
    linear-gradient(to right,rgba(169,196,214,.30) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,196,214,.30) 1px,transparent 1px);
  background-size:var(--cell) var(--cell);
}
.bp-section--paper{background-color:var(--paper)}
.bp-section--flat{background-image:none}
.bp-section--dark{
  background-color:var(--ink);
  background-image:
    linear-gradient(to right,rgba(169,196,214,.14) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,196,214,.14) 1px,transparent 1px);
  color:var(--on-dark);
}
.bp-section--dark h2,.bp-section--dark h3,.bp-section--dark h4{color:var(--cream)}

.sec-head{display:grid;gap:14px;max-width:52em;margin-bottom:clamp(28px,4vw,52px)}
.sec-head__title{font-size:clamp(26px,3.6vw,44px)}
.sec-head__desc{font-size:17px;color:var(--ink-soft);max-width:38em}
.bp-section--dark .sec-head__desc{color:var(--on-dark-soft)}
.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:13px;font-weight:600;
  letter-spacing:.12em;text-transform:uppercase;color:var(--sky-deep);
}
.bp-section--dark .eyebrow{color:var(--green)}
.idx{color:var(--flame);font-weight:700}
.lede{font-size:clamp(17px,1.7vw,20px);line-height:1.78;color:var(--ink-soft);max-width:36em}
.display{
  font-weight:900;font-size:clamp(48px,7vw,108px);line-height:1.04;
  letter-spacing:-.03em;color:var(--ink-brown);
}
.display__ghost{color:transparent;-webkit-text-stroke:1px var(--grid)}
.quote{
  font-family:var(--font-serif);font-weight:600;
  font-size:clamp(19px,2.2vw,26px);line-height:1.65;color:var(--ink-brown);
  padding-left:20px;border-left:3px solid var(--flame);
}
.rule{height:1px;background:var(--mist);border:0;margin:0}

.prose{max-width:38em;font-size:17px;line-height:1.8;color:var(--ink)}
.prose p+p{margin-top:1em}
.prose h2{margin:1.6em 0 .6em}
.prose h3{margin:1.4em 0 .5em}
.prose ul,.prose ol{margin:1em 0;padding-left:1.2em;list-style:disc}
.prose li+li{margin-top:.4em}

.crumbs{font-size:13px;color:var(--ink-mute);margin-bottom:18px}
.crumbs ol{display:flex;flex-wrap:wrap;gap:8px;align-items:center}
.crumbs li+li::before{content:"/";margin-right:8px;color:var(--grid)}

/* ---------- 05 Buttons & chips ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5em;
  padding:.72em 1.35em;border:1px solid transparent;border-radius:999px;
  font-size:15px;font-weight:700;letter-spacing:.02em;line-height:1.2;
  cursor:pointer;background:transparent;
  transition:background-color var(--ease),border-color var(--ease),color var(--ease),transform var(--ease);
}
.btn--primary{background:var(--sky);color:var(--cream)}
.btn--primary:hover{background:var(--sky-deep)}
.btn--ghost{border-color:var(--grid);color:var(--ink)}
.btn--ghost:hover{border-color:var(--green);background:rgba(61,220,132,.10);color:var(--sky-deep)}
.btn--outline{border-color:var(--ink);color:var(--ink)}
.btn--outline:hover{background:var(--ink);color:var(--cream)}
.btn--sm{padding:.5em 1em;font-size:14px}
.btn--block{width:100%;justify-content:center}

.chip-row{display:flex;flex-wrap:wrap;gap:10px}
.chip{
  display:inline-flex;align-items:center;gap:.4em;
  padding:.4em .9em;border:1px solid var(--mist);border-radius:999px;
  background:var(--cream);font-size:14px;font-weight:600;color:var(--ink-soft);
  cursor:pointer;transition:border-color var(--ease),color var(--ease),background-color var(--ease);
}
.chip:hover{border-color:var(--grid);color:var(--ink)}
.chip.is-active{border-color:var(--green);background:rgba(61,220,132,.14);color:var(--sky-deep)}

/* ---------- 06 Cards / stats / frames ---------- */
.card{
  position:relative;
  background:var(--cloud);
  border:1px solid var(--mist);
  border-radius:var(--radius-organic);
  padding:clamp(18px,2vw,26px);
  transition:transform var(--ease),border-color var(--ease),box-shadow var(--ease);
}
.card:hover{transform:translateY(-2px);border-color:var(--green);box-shadow:var(--shadow)}
.card__idx{font-family:var(--font-mono);font-size:13px;font-weight:700;color:var(--flame)}
.card__title{font-size:20px;margin-top:8px}
.card__desc{margin-top:8px;font-size:16px;color:var(--ink-soft)}
.card__meta{margin-top:14px;font-size:13px;color:var(--sky-deep);letter-spacing:.02em}
.bp-section--dark .card{background:#26333F;border-color:rgba(169,196,214,.28)}
.bp-section--dark .card__desc{color:var(--on-dark-soft)}

.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:1px;background:var(--mist);border:1px solid var(--mist)}
.stat{background:var(--cloud);padding:18px 20px}
.stat__num{display:block;font-family:var(--font-mono);font-size:clamp(26px,3.4vw,42px);font-weight:700;line-height:1.1;color:var(--sky-deep)}
.stat__label{display:block;margin-top:6px;font-size:13px;letter-spacing:.04em;color:var(--ink-mute)}

.frame{
  position:relative;overflow:hidden;aspect-ratio:16/10;
  border:1px solid var(--mist);border-radius:var(--radius-organic);
  background:linear-gradient(155deg,#DCE8F1 0%,#EFF4F8 55%,#E7EEF4 100%);
}
.frame--16x9{aspect-ratio:16/9}
.frame--4x3{aspect-ratio:4/3}
.frame--1x1{aspect-ratio:1/1}
.frame--tall{aspect-ratio:3/4}
.frame--wide{aspect-ratio:21/9}
.frame img{width:100%;height:100%;object-fit:cover}
.frame__ph{
  position:absolute;inset:0;display:flex;align-items:center;justify-content:center;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;
  color:var(--sky-deep);text-transform:uppercase;
  background-image:
    linear-gradient(to right,rgba(169,196,214,.4) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,196,214,.4) 1px,transparent 1px);
  background-size:32px 32px;
}
.frame__caption{
  position:absolute;left:0;right:0;bottom:0;padding:14px 16px;
  font-size:13px;color:var(--cream);
  background:linear-gradient(to top,rgba(31,42,54,.86),transparent);
}

/* ---------- 07 Table / details / form fields ---------- */
.data-table{font-size:15px}
.data-table th,.data-table td{padding:12px 14px;border-bottom:1px solid var(--mist);text-align:left;vertical-align:top}
.data-table thead th{background:var(--paper);font-size:13px;letter-spacing:.08em;color:var(--ink-soft)}
.data-table tbody tr:hover{background:rgba(169,196,214,.12)}
.data-table .mono{color:var(--sky-deep)}

.acc{border-top:1px solid var(--mist);padding:14px 0}
.acc:last-of-type{border-bottom:1px solid var(--mist)}
.acc summary{
  display:flex;justify-content:space-between;gap:16px;
  font-weight:700;font-size:17px;color:var(--ink-brown);cursor:pointer;list-style:none;
}
.acc summary::-webkit-details-marker{display:none}
.acc summary::after{content:"＋";color:var(--sky);font-weight:700}
.acc[open] summary::after{content:"－";color:var(--green)}
.acc[open] summary{color:var(--sky-deep)}
.acc__body{padding-top:10px;font-size:16px;color:var(--ink-soft);max-width:44em}

.field{display:block;margin-bottom:18px}
.field__label{display:block;margin-bottom:6px;font-size:14px;font-weight:700;color:var(--ink)}
.input,.select,.textarea{
  width:100%;padding:12px 14px;font-size:16px;color:var(--ink);
  background:var(--cream);border:1px solid var(--grid);border-radius:8px;
  transition:border-color var(--ease),box-shadow var(--ease);
}
.textarea{min-height:130px;resize:vertical}
.input:focus,.select:focus,.textarea:focus{
  border-color:var(--green);box-shadow:0 0 0 3px rgba(61,220,132,.25);outline:none;
}
.form-note{margin-top:10px;font-size:13px;color:var(--ink-mute)}
.form-status{font-size:14px;font-weight:600;color:var(--sky-deep)}
.form-status[data-state="err"]{color:var(--flame)}

/* ---------- 08 Side index ---------- */
.side-index{
  display:grid;gap:2px;align-self:start;
  border-left:1px solid var(--mist);
  position:sticky;top:calc(var(--header-h) + 24px);
}
.side-index__link{
  display:block;padding:8px 14px;margin-left:-1.5px;
  border-left:2px solid transparent;
  font-size:14px;color:var(--ink-mute);
  transition:color var(--ease),border-color var(--ease);
}
.side-index__link:hover{color:var(--ink)}
.side-index__link.is-active{border-left-color:var(--green);color:var(--sky-deep);font-weight:700}

/* ---------- 09 Skip link ---------- */
.skip-link{
  position:fixed;top:10px;left:12px;z-index:200;
  padding:10px 18px;border-radius:6px;
  background:var(--ink);color:var(--cream);
  font-size:14px;font-weight:700;
  transform:translateY(-180%);
  transition:transform var(--ease);
}
.skip-link:focus{transform:none;outline:2px solid var(--green);outline-offset:2px}

/* ---------- 10 Header ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  color:var(--ink);
  background:transparent;
  transition:background-color .25s ease,box-shadow .25s ease,color .25s ease;
}
.site-header__inner{
  display:flex;align-items:center;gap:clamp(12px,2vw,26px);
  min-height:var(--header-h);
}
.site-header__meter{position:absolute;left:0;right:0;bottom:0;height:2px;overflow:hidden}
.site-header__meterbar{
  display:block;height:100%;width:100%;
  background:linear-gradient(90deg,var(--green) 0%,var(--sky) 100%);
  transform:scaleX(0);transform-origin:left center;
}

.brand{
  display:inline-flex;align-items:baseline;gap:8px;
  font-size:clamp(17px,1.5vw,20px);font-weight:800;letter-spacing:-.02em;white-space:nowrap;
}
.brand__mark{color:currentColor}
.brand__suffix{
  font-family:var(--font-mono);font-size:11px;font-weight:700;letter-spacing:.1em;
  padding:3px 6px;border:1px solid rgba(61,220,132,.55);border-radius:3px;
  color:var(--sky-deep);background:rgba(61,220,132,.16);
}

.site-nav{flex:1 1 auto;margin-left:clamp(14px,4vw,56px)}
.site-nav__list{display:grid;gap:2px}
.site-nav__link{
  position:relative;display:block;padding:12px 2px;
  font-size:17px;font-weight:700;color:inherit;
  border-bottom:1px solid var(--mist);
}
.site-nav__link::after{
  content:"";position:absolute;left:0;right:0;bottom:-1px;height:2px;
  background:var(--green);transform:scaleX(0);transform-origin:left center;
  transition:transform var(--ease);
}
.site-nav__link:hover::after,
.site-nav__link:focus-visible::after,
.site-nav__link[aria-current="page"]::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--sky-deep)}
.site-nav__foot{display:grid;gap:10px;margin-top:20px}
.site-nav__note{font-size:13px;color:var(--ink-mute)}

.header-actions{display:none;align-items:center;gap:10px;margin-left:auto}

.nav-toggle{
  display:inline-flex;align-items:center;gap:9px;margin-left:auto;
  padding:8px 14px;border:1px solid var(--grid);border-radius:999px;
  background:transparent;color:inherit;font-size:14px;font-weight:700;cursor:pointer;
  transition:border-color var(--ease),color var(--ease);
}
.nav-toggle:hover{border-color:var(--green)}
.nav-toggle__bars{display:grid;gap:4px;width:18px}
.nav-toggle__bars i{display:block;height:2px;border-radius:2px;background:currentColor;transition:transform var(--ease),opacity var(--ease)}
[data-site-header][data-open] .nav-toggle{border-color:var(--green);color:var(--sky-deep)}
[data-site-header][data-open] .nav-toggle__bars i:nth-child(1){transform:translateY(6px) rotate(45deg)}
[data-site-header][data-open] .nav-toggle__bars i:nth-child(2){opacity:0}
[data-site-header][data-open] .nav-toggle__bars i:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

.header-rule{
  height:5px;opacity:0;
  background-image:repeating-linear-gradient(to right,var(--grid) 0 1px,transparent 1px 32px);
  transition:opacity var(--ease);
}

.site-header.is-scrolled{
  background:rgba(247,249,252,.95);
  box-shadow:0 1px 0 var(--mist),0 12px 28px rgba(31,42,54,.07);
}
.site-header.is-scrolled .header-rule{opacity:.55}

[data-hero="dark"] .site-header:not(.is-scrolled){color:var(--cream)}
[data-hero="dark"] .site-header:not(.is-scrolled) .site-nav__link[aria-current="page"]{color:var(--cream)}
[data-hero="dark"] .site-header:not(.is-scrolled) .brand__suffix{
  color:var(--cream);border-color:rgba(247,249,252,.5);background:rgba(61,220,132,.2);
}
[data-hero="dark"] .site-header:not(.is-scrolled) .btn--ghost,
[data-hero="dark"] .site-header:not(.is-scrolled) .nav-toggle{
  border-color:rgba(247,249,252,.42);color:var(--cream);
}
[data-hero="dark"] .site-header:not(.is-scrolled) .nav-toggle__bars i{background:var(--cream)}

@media (min-width:1024px){
  .site-nav{
    position:static;opacity:1;visibility:visible;transform:none;
    pointer-events:auto;background:none;border:0;box-shadow:none;padding:0;
    max-height:none;overflow:visible;
  }
  .site-nav__list{display:flex;flex-wrap:wrap;gap:clamp(10px,1.6vw,26px)}
  .site-nav__link{padding:8px 2px;font-size:15px;font-weight:600;border-bottom:0}
  .site-nav__foot{display:none}
  .header-actions{display:flex}
  .nav-toggle{display:none}
}

@media (max-width:1023px){
  .site-nav{
    position:fixed;top:var(--header-h);left:0;right:0;
    max-height:calc(100vh - var(--header-h));overflow:auto;
    padding:16px var(--gutter) 30px;
    background:var(--cloud);
    border-top:1px solid var(--mist);
    box-shadow:0 26px 44px rgba(31,42,54,.18);
    opacity:0;visibility:hidden;transform:translateY(-10px);pointer-events:none;
    transition:opacity var(--ease),transform var(--ease),visibility var(--ease);
  }
  [data-site-header][data-open="true"] .site-nav{
    opacity:1;visibility:visible;transform:none;pointer-events:auto;
  }
  .site-header.is-scrolled,
  [data-site-header][data-open="true"] .site-header{
    background:rgba(247,249,252,.95);
  }
  [data-site-header][data-open="true"] .site-header__inner,
  [data-site-header][data-open="true"] .brand,
  [data-site-header][data-open="true"] .nav-toggle{color:var(--ink)}
  [data-site-header][data-open="true"] .nav-toggle__bars i{background:var(--ink)}
}

/* ---------- 11 Footer ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(48px,6vw,88px);
  background:var(--ink);
  color:var(--on-dark);
  overflow:hidden;
}
.footer-sky{
  position:absolute;top:0;left:0;right:0;height:clamp(96px,15vw,200px);
  pointer-events:none;
  background:
    radial-gradient(46% 130% at 10% 100%,rgba(58,124,165,.55),transparent 72%),
    radial-gradient(54% 140% at 52% 100%,rgba(169,196,214,.26),transparent 74%),
    radial-gradient(42% 120% at 92% 100%,rgba(61,220,132,.14),transparent 72%);
}
.footer-sky__grid{
  position:absolute;inset:0;
  background-image:
    linear-gradient(to right,rgba(169,196,214,.20) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,196,214,.20) 1px,transparent 1px);
  background-size:56px 56px;
  -webkit-mask-image:linear-gradient(to bottom,#000,transparent);
  mask-image:linear-gradient(to bottom,#000,transparent);
}
.site-footer__inner{position:relative;padding:clamp(52px,6vw,86px) 0 30px}

.footer-grid{display:grid;gap:clamp(26px,3.4vw,44px);grid-template-columns:1fr}
@media (min-width:640px){
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand,.footer-col--contact{grid-column:1/-1}
}
@media (min-width:1024px){
  .footer-grid{grid-template-columns:1.35fr .7fr .7fr .7fr 1.6fr}
  .footer-brand,.footer-col--contact{grid-column:auto}
}

.site-footer .brand{color:var(--cream)}
.footer-brand__line{margin-top:16px;font-size:15px;color:var(--on-dark)}
.footer-brand__meta{margin-top:6px;font-family:var(--font-mono);font-size:13px;letter-spacing:.08em;color:var(--on-dark-soft)}

.footer-col__title{
  display:flex;align-items:center;gap:8px;
  margin-bottom:16px;font-size:13px;font-weight:700;
  letter-spacing:.14em;color:var(--grid);text-transform:uppercase;
}
.footer-col__title::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--green)}
.footer-list{display:grid;gap:10px}
.footer-link{
  position:relative;display:inline-block;
  font-size:15px;color:var(--on-dark);
  transition:color var(--ease);
}
.footer-link::after{
  content:"";position:absolute;left:0;right:0;bottom:-2px;height:1px;
  background:var(--green);transform:scaleX(0);transform-origin:left center;
  transition:transform var(--ease);
}
.footer-link:hover{color:var(--cream)}
.footer-link:hover::after{transform:scaleX(1)}

.footer-contact{display:grid;gap:14px}
.contact-item{display:flex;flex-wrap:wrap;align-items:center;gap:6px 10px}
.contact-item__key{flex:0 0 100%;font-size:12px;letter-spacing:.14em;color:var(--on-dark-soft)}
.contact-item__val{font-size:14px;line-height:1.6;color:var(--cream);word-break:break-all}
.copy-btn{
  padding:3px 10px;border:1px solid rgba(169,196,214,.45);border-radius:999px;
  background:transparent;color:var(--on-dark-soft);
  font-size:12px;font-weight:700;cursor:pointer;
  transition:border-color var(--ease),color var(--ease),background-color var(--ease);
}
.copy-btn:hover{border-color:var(--green);color:var(--cream)}
.copy-btn[data-copied="true"]{border-color:var(--green);background:rgba(61,220,132,.16);color:var(--green)}
.footer-note{margin-top:16px;font-size:13px;line-height:1.8;color:var(--on-dark-soft);max-width:44em}

.footer-legal{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:14px 26px;margin-top:clamp(34px,5vw,58px);padding-top:20px;
  border-top:1px solid rgba(169,196,214,.28);
}
.footer-legal__links{display:flex;flex-wrap:wrap;gap:10px 22px}
.footer-legal__links .footer-link{font-size:14px;color:var(--on-dark-soft)}
.footer-legal__copy{font-size:13px;color:var(--on-dark-soft)}

/* ---------- 12 Motion ---------- */
[data-reveal]{opacity:0;transform:translateY(12px);transition:opacity .5s ease,transform .5s ease}
[data-reveal].is-in{opacity:1;transform:none}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  [data-reveal]{opacity:1;transform:none;transition:none}
  .site-header,.site-header__meterbar,.site-nav,.nav-toggle__bars i,
  .card,.btn,.chip,.footer-link,.footer-link::after,.site-nav__link::after,
  .skip-link,.copy-btn,.input,.select,.textarea{transition:none}
  .card:hover{transform:none}
}