:root{
  --ink-900:#05100C;
  --ink-800:#0A1D16;
  --ink-700:#10291F;
  --line:#7E8F88;
  --silver:#C6D2CD;
  --paper:#F4F8F6;
  --signal:#2DF0C6;
  --signal-deep:#12A98C;
  --warm:#FF7A33;
  --alert:#FF5A4E;
  --shell:1240px;
  --r-card:14px;
  --r-pill:999px;
  --ease:cubic-bezier(.2,.7,.3,1);
  --font-sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC","Noto Sans SC",system-ui,sans-serif;
  --font-serif:"Songti SC","Source Han Serif SC","Noto Serif SC","SimSun",serif;
  --font-mono:ui-monospace,"SFMono-Regular","JetBrains Mono","Roboto Mono",Menlo,Consolas,monospace;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.7;
  color:var(--silver);
  background-color:var(--ink-900);
  background-image:
    radial-gradient(900px 520px at 82% -10%, rgba(45,240,198,.07), transparent 62%),
    radial-gradient(720px 460px at 4% 10%, rgba(255,122,51,.05), transparent 64%);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
}
img,svg{max-width:100%;display:block}
h1,h2,h3,h4,p,ul,ol,figure{margin:0;padding:0}
ul,ol{list-style:none}
button{font:inherit}
::selection{background:var(--signal);color:#04120D}
:focus-visible{outline:2px solid var(--signal);outline-offset:3px;border-radius:4px}
.yb-skip{
  position:absolute;left:12px;top:-72px;z-index:200;
  padding:10px 18px;border-radius:10px;
  background:var(--signal);color:#04120D;
  font-size:14px;font-weight:700;text-decoration:none;
  transition:top .18s var(--ease);
}
.yb-skip:focus{top:12px}
/* ---------- shell / layout ---------- */
.yb-shell{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:20px}
.yb-section{padding-block:clamp(48px,7vw,96px)}
.yb-stack{display:flex;flex-direction:column;gap:16px}
.yb-grid{display:grid;grid-template-columns:repeat(12,1fr);gap:16px}
.yb-span-3{grid-column:span 3}
.yb-span-4{grid-column:span 4}
.yb-span-5{grid-column:span 5}
.yb-span-6{grid-column:span 6}
.yb-span-7{grid-column:span 7}
.yb-span-8{grid-column:span 8}
.yb-span-9{grid-column:span 9}
.yb-span-10{grid-column:span 10}
.yb-span-12{grid-column:span 12}
/* ---------- type ---------- */
.yb-display{
  font-family:var(--font-sans);font-weight:900;
  font-size:clamp(30px,4.6vw,56px);line-height:1.04;
  letter-spacing:-.02em;color:var(--paper);
}
.yb-title{
  font-family:var(--font-sans);font-weight:900;
  font-size:clamp(22px,2.6vw,32px);line-height:1.2;
  letter-spacing:-.015em;color:var(--paper);
}
.yb-eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;color:var(--line);
}
.yb-eyebrow::before{
  content:"";width:6px;height:6px;border-radius:1px;
  background:var(--signal);flex:0 0 auto;
}
.yb-serif{font-family:var(--font-serif);font-weight:600;line-height:1.6;color:var(--paper)}
.yb-num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:-.01em}
.yb-lead{font-size:17px;line-height:1.75;color:var(--silver)}
.yb-muted{font-size:13px;line-height:1.6;color:var(--line)}
.yb-link{
  color:var(--signal);text-decoration:none;
  border-bottom:1px solid rgba(45,240,198,.35);padding-bottom:1px;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.yb-link:hover{color:var(--paper);border-bottom-color:var(--paper)}
.yb-rule{height:1px;border:0;margin:0;background:linear-gradient(90deg,rgba(126,143,136,.45),rgba(126,143,136,0))}
/* ---------- panels ---------- */
.yb-card{
  position:relative;
  background:var(--ink-700);
  border:1px solid rgba(126,143,136,.24);
  border-radius:var(--r-card);
  padding:clamp(18px,2.4vw,26px);
  transition:border-color .18s var(--ease),transform .16s var(--ease);
}
.yb-card:hover{border-color:rgba(45,240,198,.45)}
.yb-card--cut{
  border-radius:0;
  clip-path:polygon(0 0,calc(100% - 10px) 0,100% 10px,100% 100%,0 100%);
  border-color:transparent;
  box-shadow:none;
  background-image:linear-gradient(180deg,rgba(45,240,198,.14),rgba(45,240,198,0) 40%);
  background-color:var(--ink-700);
}
.yb-card--cut::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:1px;
  background:rgba(126,143,136,.3);
}
.yb-tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:5px 9px;border-radius:4px;
  border:1px solid rgba(126,143,136,.45);
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;color:var(--silver);
}
.yb-tag--signal{
  color:var(--signal);border-color:rgba(45,240,198,.45);
  background:rgba(45,240,198,.08);
}
.yb-tag--warm{
  color:var(--warm);border-color:rgba(255,122,51,.45);
  background:rgba(255,122,51,.08);
}
.yb-kv{
  display:flex;align-items:baseline;justify-content:space-between;gap:12px;
  padding:10px 0;font-size:14px;
  border-bottom:1px dashed rgba(126,143,136,.22);
}
.yb-kv__key{color:var(--line)}
.yb-kv__val{font-family:var(--font-mono);font-weight:600;color:var(--paper);font-variant-numeric:tabular-nums}
.yb-table{width:100%;border-collapse:collapse;font-size:14px;font-variant-numeric:tabular-nums}
.yb-table th,.yb-table td{text-align:left;padding:12px 14px;border-bottom:1px solid rgba(126,143,136,.18)}
.yb-table th{
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;color:var(--line);
}
.yb-table tbody tr{transition:background-color .18s var(--ease)}
.yb-table tbody tr:hover{background:rgba(16,41,31,.72)}
/* ---------- buttons ---------- */
.yb-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 22px;border-radius:var(--r-pill);
  border:1px solid rgba(126,143,136,.45);
  background:transparent;color:var(--silver);
  font-size:14px;font-weight:600;text-decoration:none;cursor:pointer;
  transition:border-color .18s var(--ease),color .18s var(--ease),background-color .18s var(--ease),transform .12s var(--ease);
}
.yb-btn:hover{border-color:var(--signal);color:var(--paper)}
.yb-btn:active{transform:scale(.98)}
.yb-btn--signal{background:var(--signal);border-color:var(--signal);color:#04120D}
.yb-btn--signal:hover{background:#5ff8d8;border-color:#5ff8d8;color:#04120D}
.yb-btn--ghost{border-color:rgba(45,240,198,.5);color:var(--signal)}
.yb-btn--ghost:hover{background:rgba(45,240,198,.1);color:var(--signal)}
.yb-btn--warm{border-color:rgba(255,122,51,.55);color:var(--warm)}
.yb-btn--warm:hover{background:rgba(255,122,51,.12);border-color:var(--warm);color:var(--warm)}
/* ---------- crumbs ---------- */
.yb-crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:13px;color:var(--line)}
.yb-crumbs li{display:flex;align-items:center;gap:8px}
.yb-crumbs li+li::before{content:"/";color:rgba(126,143,136,.5)}
.yb-crumbs a{color:var(--silver);text-decoration:none;transition:color .18s var(--ease)}
.yb-crumbs a:hover{color:var(--signal)}
/* ---------- media ---------- */
.yb-media{
  position:relative;overflow:hidden;
  border-radius:var(--r-card);
  border:1px solid rgba(126,143,136,.2);
  aspect-ratio:16/10;
  background-color:var(--ink-800);
  background-image:
    radial-gradient(120% 90% at 74% 0%, rgba(45,240,198,.18), transparent 56%),
    radial-gradient(90% 70% at 8% 100%, rgba(255,122,51,.14), transparent 62%),
    repeating-linear-gradient(90deg, rgba(126,143,136,.15) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(0deg, rgba(126,143,136,.11) 0 1px, transparent 1px 64px);
}
.yb-media--wide{aspect-ratio:21/9}
.yb-media--tall{aspect-ratio:3/4}
.yb-media--square{aspect-ratio:1/1}
.yb-media img{width:100%;height:100%;object-fit:cover}
.yb-media__label{
  position:absolute;left:12px;bottom:12px;
  padding:5px 9px;border-radius:4px;
  background:rgba(5,16,12,.78);
  border:1px solid rgba(45,240,198,.4);
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.08em;color:var(--signal);
}
/* ---------- header ---------- */
.yb-header{position:sticky;top:0;z-index:80;padding:10px 16px 0}
.yb-progress{
  position:fixed;top:0;left:0;width:100%;height:2px;z-index:100;
  transform-origin:0 50%;transform:scaleX(var(--p,0));
  background:linear-gradient(90deg,var(--signal),var(--warm));
  pointer-events:none;
}
.yb-header__inner{
  position:relative;
  max-width:var(--shell);margin-inline:auto;
  display:flex;align-items:center;gap:14px;
  min-height:64px;padding:8px 10px 8px 18px;
  border-radius:var(--r-pill);
  border:1px solid rgba(126,143,136,.26);
  background:rgba(16,41,31,.82);
  backdrop-filter:blur(14px) saturate(120%);
  -webkit-backdrop-filter:blur(14px) saturate(120%);
  box-shadow:0 12px 32px rgba(0,0,0,.35);
  transition:min-height .2s var(--ease),background-color .2s var(--ease),padding .2s var(--ease);
}
.yb-header[data-compact] .yb-header__inner{
  min-height:52px;padding-block:4px;
  background:rgba(10,29,22,.95);
}
.yb-brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--paper);flex:0 0 auto}
.yb-brand__mark{
  position:relative;flex:0 0 auto;
  width:26px;height:26px;border-radius:6px;
  background:var(--ink-900);
  border:1px solid rgba(45,240,198,.55);
}
.yb-brand__mark::before{
  content:"";position:absolute;inset:5px;background:var(--signal);
  clip-path:polygon(0 0,100% 0,100% 36%,36% 100%,0 100%);
}
.yb-brand__text{display:flex;flex-direction:column;gap:1px;line-height:1.2}
.yb-brand__name{font-size:15px;font-weight:900;letter-spacing:-.01em;color:var(--paper);white-space:nowrap}
.yb-brand__tag{
  display:block;max-height:18px;overflow:hidden;
  font-size:11px;font-weight:400;letter-spacing:.02em;color:var(--line);
  transition:max-height .2s var(--ease),opacity .2s var(--ease);
}
.yb-header[data-compact] .yb-brand__tag{max-height:0;opacity:0}
.yb-nav{flex:1 1 auto;display:flex;justify-content:center;min-width:0}
.yb-nav__list{display:flex;align-items:center;gap:2px}
.yb-nav__item{display:flex}
.yb-nav__link{
  display:inline-block;padding:8px 13px;border-radius:var(--r-pill);
  border:1px solid transparent;
  font-size:13.5px;font-weight:500;color:var(--silver);
  text-decoration:none;white-space:nowrap;
  transition:color .18s var(--ease),border-color .18s var(--ease),background-color .18s var(--ease),padding .2s var(--ease);
}
.yb-nav__link:hover{color:var(--paper);border-color:rgba(45,240,198,.5)}
.yb-nav__link[aria-current="page"]{
  background:var(--signal);border-color:var(--signal);
  color:#04120D;font-weight:700;
}
.yb-header[data-compact] .yb-nav__link{padding:6px 10px;font-size:13px}
.yb-header__actions{display:flex;align-items:center;gap:8px;flex:0 0 auto;margin-left:auto}
.yb-header__cta{
  display:inline-flex;align-items:center;justify-content:center;
  padding:9px 18px;border-radius:var(--r-pill);
  background:var(--signal);color:#04120D;
  font-size:13px;font-weight:700;text-decoration:none;white-space:nowrap;
  box-shadow:0 0 0 1px rgba(45,240,198,.4),0 6px 18px rgba(45,240,198,.16);
  transition:background-color .18s var(--ease),transform .12s var(--ease);
}
.yb-header__cta:hover{background:#5ff8d8}
.yb-header__cta:active{transform:scale(.98)}
.yb-burger{
  display:none;width:40px;height:40px;padding:0;
  flex-direction:column;align-items:center;justify-content:center;gap:4px;
  border-radius:50%;border:1px solid rgba(126,143,136,.42);
  background:transparent;cursor:pointer;
  transition:border-color .18s var(--ease);
}
.yb-burger:hover{border-color:var(--signal)}
.yb-burger__bar{display:block;width:16px;height:1.5px;background:var(--silver);transition:transform .18s var(--ease),opacity .18s var(--ease)}
.yb-burger[aria-expanded="true"] .yb-burger__bar:nth-child(1){transform:translateY(5.5px) rotate(45deg)}
.yb-burger[aria-expanded="true"] .yb-burger__bar:nth-child(2){opacity:0}
.yb-burger[aria-expanded="true"] .yb-burger__bar:nth-child(3){transform:translateY(-5.5px) rotate(-45deg)}
/* ---------- back to top ---------- */
.yb-top{
  position:fixed;right:18px;bottom:18px;z-index:90;
  width:46px;height:46px;border-radius:50%;
  display:inline-flex;align-items:center;justify-content:center;
  background:rgba(16,41,31,.92);
  border:1px solid rgba(45,240,198,.5);
  color:var(--signal);font-family:var(--font-mono);font-size:15px;line-height:1;
  cursor:pointer;
  backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);
  box-shadow:0 10px 26px rgba(0,0,0,.45);
  transition:transform .16s var(--ease),border-color .18s var(--ease);
}
.yb-top:hover{transform:translateY(-2px);border-color:var(--signal)}
.yb-top:active{transform:scale(.96)}
.yb-top[hidden]{display:none}
/* ---------- footer ---------- */
.yb-footer{
  background:var(--ink-800);
  border-top:1px solid rgba(126,143,136,.22);
  margin-top:clamp(32px,6vw,72px);
}
.yb-footer__inner{max-width:var(--shell);margin-inline:auto;padding:clamp(40px,6vw,72px) 20px 0}
.yb-footer__grid{display:grid;grid-template-columns:1.6fr 1fr 1.3fr 1fr;gap:clamp(20px,4vw,48px)}
.yb-footer__col{display:flex;flex-direction:column;gap:14px;min-width:0}
.yb-footer__col--brand{gap:16px}
.yb-footer__title{
  font-family:var(--font-mono);font-size:11px;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;color:var(--signal);
}
.yb-footer__lead{font-size:14px;line-height:1.75;color:var(--silver);max-width:34ch}
.yb-footer__list{display:flex;flex-direction:column;gap:8px}
.yb-footer__link{
  display:inline-block;font-size:14px;color:var(--silver);text-decoration:none;
  border-bottom:1px solid transparent;padding-bottom:1px;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.yb-footer__link:hover{color:var(--signal);border-bottom-color:rgba(45,240,198,.6)}
.yb-footer__meta{display:flex;flex-direction:column;gap:8px}
.yb-footer__meta-item{
  display:flex;flex-wrap:wrap;gap:8px;
  font-size:13px;line-height:1.6;color:var(--silver);
  font-family:var(--font-mono);word-break:break-word;
}
.yb-footer__meta-key{
  flex:0 0 auto;padding:2px 6px;border-radius:3px;
  border:1px solid rgba(126,143,136,.35);
  font-size:10px;letter-spacing:.08em;color:var(--line);
}
.yb-footer__note{font-size:12px;line-height:1.65;color:var(--line);max-width:32ch}
.yb-footer__breath{
  height:6px;margin-top:clamp(28px,4vw,48px);border-radius:1px;
  background-image:
    repeating-linear-gradient(90deg, rgba(45,240,198,.55) 0 2px, transparent 2px 12px),
    linear-gradient(90deg, rgba(45,240,198,0), rgba(45,240,198,.22), rgba(255,122,51,.18), rgba(45,240,198,0));
  opacity:.7;
}
.yb-footer__base{
  display:flex;align-items:flex-end;justify-content:space-between;gap:16px;
  padding:16px 0 22px;
  border-bottom:1px solid rgba(126,143,136,.16);
}
.yb-footer__copy{font-size:12px;color:var(--line);letter-spacing:.01em}
.yb-footer__wordmark{
  font-family:var(--font-sans);font-weight:900;
  font-size:clamp(26px,5.2vw,52px);line-height:1;
  letter-spacing:-.03em;white-space:nowrap;
  color:rgba(198,210,205,.1);
}
/* ---------- responsive ---------- */
@media (max-width:1100px){
  .yb-footer__grid{grid-template-columns:1.4fr 1fr 1.2fr}
  .yb-footer__col--brand{grid-column:span 3}
}
@media (max-width:900px){
  .yb-grid{grid-template-columns:repeat(6,1fr)}
  .yb-span-3,.yb-span-4{grid-column:span 3}
  .yb-span-5,.yb-span-6,.yb-span-7,.yb-span-8,.yb-span-9,.yb-span-10,.yb-span-12{grid-column:span 6}
  .yb-footer__grid{grid-template-columns:repeat(2,1fr);gap:28px}
  .yb-footer__col--brand{grid-column:span 2}
}
@media (max-width:959px){
  .yb-burger{display:flex}
  .yb-nav{
    position:absolute;left:0;right:0;top:calc(100% + 8px);
    flex-direction:column;justify-content:flex-start;
    padding:12px;
    border-radius:18px;
    border:1px solid rgba(126,143,136,.28);
    background:rgba(10,29,22,.98);
    box-shadow:0 24px 48px rgba(0,0,0,.5);
    opacity:0;visibility:hidden;transform:translateY(-10px);
    transition:opacity .18s var(--ease),transform .18s var(--ease),visibility .18s var(--ease);
  }
  .yb-nav[data-open]{opacity:1;visibility:visible;transform:translateY(0)}
  .yb-nav__list{flex-direction:column;align-items:stretch;gap:2px;width:100%}
  .yb-nav__link,.yb-header[data-compact] .yb-nav__link{
    display:block;padding:12px 14px;border-radius:12px;font-size:15px;
  }
  .yb-header__inner{padding-left:14px}
}
@media (max-width:640px){
  .yb-shell{padding-inline:16px}
  .yb-header{padding:8px 10px 0}
  .yb-header__inner{min-height:58px;gap:10px;padding:6px 8px 6px 12px;border-radius:18px}
  .yb-header[data-compact] .yb-header__inner{min-height:50px}
  .yb-header__cta{padding:8px 14px;font-size:12px}
  .yb-brand__mark{width:22px;height:22px}
  .yb-brand__name{font-size:14px}
  .yb-brand__tag{display:none}
  .yb-grid{grid-template-columns:repeat(2,1fr);gap:12px}
  .yb-span-3,.yb-span-4,.yb-span-5,.yb-span-6,.yb-span-7,.yb-span-8,.yb-span-9,.yb-span-10,.yb-span-12{grid-column:span 2}
  .yb-footer__grid{grid-template-columns:1fr}
  .yb-footer__col--brand{grid-column:span 1}
  .yb-footer__base{flex-direction:column;align-items:flex-start;gap:12px}
  .yb-footer__wordmark{font-size:clamp(24px,9vw,36px)}
  .yb-top{right:12px;bottom:12px;width:42px;height:42px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms!important;
    animation-iteration-count:1!important;
    transition-duration:.001ms!important;
  }
}