:root{
  --by-ink:#04100d;
  --by-ink-2:#071a16;
  --by-jade:#0d2b25;
  --by-jade-2:#123a30;
  --by-cyan:#26efd0;
  --by-orange:#ff7a33;
  --by-silver:#c6d2d3;
  --by-mist:#7f9490;
  --by-text:#e6f0ee;
  --by-line:rgba(198,226,220,.13);
  --by-line-strong:rgba(38,239,208,.40);
  --by-wrap:1240px;
  --by-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Courier New",monospace;
  --by-sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
}
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  scroll-padding-top:132px;
}
body{
  margin:0;
  background-color:var(--by-ink);
  background-image:
    radial-gradient(1100px 520px at 10% -12%,rgba(38,239,208,.10),transparent 62%),
    radial-gradient(900px 480px at 100% 0%,rgba(255,122,51,.07),transparent 64%);
  background-repeat:no-repeat;
  color:var(--by-text);
  font-family:var(--by-sans);
  font-size:16px;
  line-height:1.78;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
img{max-width:100%;display:block;height:auto}
h1,h2,h3,h4,h5,h6{margin:0 0 .6em;line-height:1.22;font-weight:750;color:#fff;letter-spacing:-.01em}
p{margin:0 0 1.05em}
p:last-child{margin-bottom:0}
ul,ol{margin:0 0 1.05em;padding-left:1.25em}
a{color:var(--by-cyan)}
b,strong{font-weight:750}
::selection{background:rgba(38,239,208,.28);color:#fff}
:focus-visible{outline:2px solid var(--by-cyan);outline-offset:3px}
@media (prefers-reduced-motion:no-preference){
  html{scroll-behavior:smooth}
  .js [data-reveal]{
    opacity:0;
    transform:translateY(18px);
    transition:opacity .55s ease,transform .55s cubic-bezier(.22,.7,.28,1);
    will-change:opacity,transform;
  }
  .js [data-reveal].is-visible{opacity:1;transform:none}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
}

/* ===== 跳至主要内容 ===== */
.by-skip{
  position:absolute;
  left:50%;
  top:8px;
  transform:translate(-50%,-220%);
  z-index:200;
  padding:10px 20px;
  background:var(--by-cyan);
  color:#04100d;
  font-size:14px;
  font-weight:750;
  text-decoration:none;
  transition:transform .2s ease;
}
.by-skip:focus{transform:translate(-50%,0)}

/* ===== 头部 ===== */
.by-header{
  position:sticky;
  top:0;
  z-index:90;
  background:rgba(4,16,13,.95);
  -webkit-backdrop-filter:blur(12px);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--by-line);
}
.by-header__top{
  background:linear-gradient(90deg,var(--by-jade) 0%,rgba(13,43,37,.42) 52%,rgba(13,43,37,0) 100%);
  border-bottom:1px solid var(--by-line);
}
.by-header__topin{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:4px 20px;
  min-height:38px;
  padding-block:6px;
  font-size:12.5px;
  color:var(--by-mist);
}
.by-header__note{margin:0;color:var(--by-silver);letter-spacing:.05em}
.by-header__status{
  display:inline-flex;
  align-items:center;
  gap:8px;
  margin:0;
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--by-mist);
}
.by-header__bar{position:relative}
.by-header__barin{
  display:flex;
  align-items:center;
  gap:clamp(14px,2.2vw,30px);
  min-height:72px;
}
.by-dot{
  display:inline-block;
  width:7px;
  height:7px;
  border-radius:50%;
  background:var(--by-cyan);
  box-shadow:0 0 0 4px rgba(38,239,208,.14);
}
.by-brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  flex:0 0 auto;
  color:inherit;
  text-decoration:none;
}
.by-brand__mark{
  display:grid;
  place-items:center;
  width:42px;
  height:42px;
  border:1px solid var(--by-line-strong);
  background:linear-gradient(150deg,rgba(38,239,208,.20),transparent 72%);
  font-family:var(--by-mono);
  font-size:15px;
  font-weight:700;
  color:var(--by-cyan);
  letter-spacing:.02em;
}
.by-brand__text{display:flex;flex-direction:column;line-height:1.16}
.by-brand__name{font-size:19px;font-weight:800;color:#fff;letter-spacing:.01em}
.by-brand__name b{color:var(--by-cyan);font-weight:800}
.by-brand__sub{
  font-family:var(--by-mono);
  font-size:10.5px;
  letter-spacing:.24em;
  color:var(--by-mist);
  text-transform:uppercase;
}
.by-brand--footer .by-brand__mark{width:38px;height:38px;font-size:14px}

/* ===== 导航 ===== */
.by-nav{margin-left:auto}
.by-nav__list{
  display:flex;
  align-items:center;
  gap:2px;
  margin:0;
  padding:0;
  list-style:none;
}
.by-nav__link{
  position:relative;
  display:block;
  padding:12px 13px;
  font-size:14.5px;
  font-weight:500;
  color:var(--by-silver);
  text-decoration:none;
  white-space:nowrap;
  transition:color .18s ease;
}
.by-nav__link::after{
  content:"";
  position:absolute;
  left:13px;
  right:13px;
  bottom:6px;
  height:2px;
  background:var(--by-orange);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .22s ease,background .22s ease;
}
.by-nav__link:hover{color:#fff}
.by-nav__link:hover::after{transform:scaleX(1);background:var(--by-cyan)}
.by-nav__link[aria-current="page"]{color:var(--by-cyan)}
.by-nav__link[aria-current="page"]::after{transform:scaleX(1)}
.by-burger{
  display:none;
  align-items:center;
  gap:10px;
  margin-left:auto;
  min-height:42px;
  padding:0 14px;
  border:1px solid var(--by-line);
  background:transparent;
  color:var(--by-silver);
  font:inherit;
  font-size:13.5px;
  cursor:pointer;
  transition:color .18s ease,border-color .18s ease;
}
.by-burger:hover{color:#fff;border-color:var(--by-line-strong)}
.by-burger__bars{position:relative;display:block;width:18px;height:2px;background:currentColor}
.by-burger__bars::before,
.by-burger__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:18px;
  height:2px;
  background:currentColor;
  transition:transform .2s ease,top .2s ease;
}
.by-burger__bars::before{top:-6px}
.by-burger__bars::after{top:6px}
.by-header[data-open] .by-burger{color:var(--by-cyan);border-color:var(--by-line-strong)}
.by-header[data-open] .by-burger__bars{background:transparent}
.by-header[data-open] .by-burger__bars::before{top:0;transform:rotate(45deg)}
.by-header[data-open] .by-burger__bars::after{top:0;transform:rotate(-45deg)}

/* ===== 阅读进度 ===== */
.by-progress{
  position:absolute;
  left:0;
  bottom:0;
  width:100%;
  height:2px;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--by-cyan),var(--by-orange));
  pointer-events:none;
}

/* ===== 容器与区块 ===== */
.by-wrap{
  width:100%;
  max-width:var(--by-wrap);
  margin-inline:auto;
  padding-inline:clamp(18px,4vw,40px);
}
.by-section{padding-block:clamp(32px,5vw,64px)}
.by-section--tight{padding-block:clamp(18px,3vw,32px)}
.by-pagehead{
  padding-block:clamp(34px,5.5vw,76px) clamp(18px,3vw,34px);
  border-bottom:1px solid var(--by-line);
  margin-bottom:clamp(24px,4vw,52px);
}

/* ===== 文本 ===== */
.by-eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin:0 0 14px;
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--by-cyan);
}
.by-eyebrow::before{content:"";width:26px;height:1px;background:var(--by-orange)}
.by-display{
  font-size:clamp(34px,6.4vw,74px);
  line-height:1.04;
  font-weight:800;
  letter-spacing:-.025em;
  margin:0 0 .45em;
  color:#fff;
}
.by-title{
  font-size:clamp(22px,3vw,34px);
  line-height:1.18;
  font-weight:780;
  letter-spacing:-.018em;
  margin:0 0 .55em;
}
.by-subtitle{font-size:clamp(16px,1.6vw,19px);font-weight:700;margin:0 0 .45em;color:#fff}
.by-lede{
  max-width:64ch;
  margin:0 0 1.05em;
  font-size:clamp(15.5px,1.5vw,18px);
  line-height:1.82;
  color:var(--by-silver);
}
.by-mono{font-family:var(--by-mono);font-variant-numeric:tabular-nums;letter-spacing:.02em}
.by-link{
  color:var(--by-cyan);
  text-decoration:none;
  border-bottom:1px solid rgba(38,239,208,.35);
  transition:border-color .18s ease;
}
.by-link:hover{border-bottom-color:var(--by-cyan)}

/* ===== 按钮 ===== */
.by-btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  min-height:44px;
  padding:0 20px;
  border:1px solid var(--by-line-strong);
  background:transparent;
  color:var(--by-text);
  font:inherit;
  font-size:14.5px;
  font-weight:650;
  text-decoration:none;
  cursor:pointer;
  transition:background .2s ease,color .2s ease,border-color .2s ease,transform .2s ease;
}
.by-btn:hover{background:rgba(38,239,208,.10);border-color:var(--by-cyan)}
.by-btn:active{transform:translateY(1px)}
.by-btn--accent{
  background:var(--by-orange);
  border-color:var(--by-orange);
  color:#1c0d03;
  font-weight:780;
}
.by-btn--accent:hover{background:#ff9155;border-color:#ff9155;color:#1c0d03}
.by-btn--ghost{border-color:var(--by-line);color:var(--by-silver)}
.by-btn--ghost:hover{color:#fff;border-color:var(--by-line-strong);background:rgba(38,239,208,.07)}

/* ===== 面板 ===== */
.by-panel{
  position:relative;
  padding:clamp(18px,2.4vw,28px);
  border:1px solid var(--by-line);
  background:linear-gradient(158deg,rgba(18,58,48,.55),rgba(7,26,22,.92));
  box-shadow:0 18px 42px -36px rgba(0,0,0,.95);
}
.by-panel--accent{border-color:var(--by-line-strong)}
.by-panel--accent::before{
  content:"";
  position:absolute;
  left:-1px;
  top:-1px;
  width:44px;
  height:2px;
  background:var(--by-orange);
}
.by-panel__head{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:14px;
  margin-bottom:14px;
  padding-bottom:12px;
  border-bottom:1px solid var(--by-line);
}

/* ===== 网格 ===== */
.by-grid{display:grid;gap:clamp(14px,2vw,24px)}
.by-grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.by-grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.by-grid--split{grid-template-columns:minmax(0,1.35fr) minmax(0,1fr)}
@media (max-width:960px){
  .by-grid--3,.by-grid--split{grid-template-columns:1fr}
}
@media (max-width:620px){
  .by-grid--2{grid-template-columns:1fr}
}

/* ===== 横向主题带 ===== */
.by-band{
  display:flex;
  align-items:center;
  gap:clamp(14px,2vw,30px);
  padding:14px 0;
  border-top:1px solid var(--by-line);
  border-bottom:1px solid var(--by-line);
  overflow-x:auto;
  scrollbar-width:thin;
}
.by-band__item{
  flex:0 0 auto;
  font-family:var(--by-mono);
  font-size:12px;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--by-mist);
}
.by-band__item--hot{color:var(--by-orange)}
.by-band__item--key{color:var(--by-cyan)}

/* ===== 图片容器（页面阶段填充） ===== */
.by-figure{
  position:relative;
  margin:0;
  aspect-ratio:16/9;
  overflow:hidden;
  border:1px solid var(--by-line);
  background-color:var(--by-jade);
  background-image:
    linear-gradient(140deg,rgba(38,239,208,.13),rgba(255,122,51,.07) 58%,transparent),
    repeating-linear-gradient(90deg,rgba(198,226,220,.07) 0 1px,transparent 1px 46px),
    repeating-linear-gradient(0deg,rgba(198,226,220,.07) 0 1px,transparent 1px 46px);
}
.by-figure--wide{aspect-ratio:21/9}
.by-figure--tall{aspect-ratio:4/5}
.by-figure--square{aspect-ratio:1/1}
.by-figure__media{
  position:absolute;
  inset:0;
  width:100%;
  height:100%;
  object-fit:cover;
}
.by-figure__caption{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  padding:26px 16px 12px;
  background:linear-gradient(180deg,transparent,rgba(4,16,13,.92));
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--by-silver);
}

/* ===== 数据指标 ===== */
.by-stat{
  display:flex;
  flex-direction:column;
  gap:5px;
  padding-left:14px;
  border-left:1px solid var(--by-line-strong);
}
.by-stat__value{
  font-family:var(--by-mono);
  font-size:clamp(21px,2.8vw,30px);
  font-weight:700;
  color:#fff;
  line-height:1.1;
}
.by-stat__label{font-size:12.5px;letter-spacing:.06em;color:var(--by-mist)}

/* ===== 徽标 ===== */
.by-badge{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 9px;
  border:1px solid var(--by-line);
  background:rgba(255,255,255,.02);
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--by-silver);
}
.by-badge--live{color:var(--by-orange);border-color:rgba(255,122,51,.45)}
.by-badge--key{color:var(--by-cyan);border-color:var(--by-line-strong)}

/* ===== 面包屑 ===== */
.by-breadcrumb{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  margin:0 0 clamp(16px,2.6vw,26px);
  padding:0;
  list-style:none;
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.1em;
  color:var(--by-mist);
}
.by-breadcrumb a{color:var(--by-silver);text-decoration:none}
.by-breadcrumb a:hover{color:var(--by-cyan)}
.by-breadcrumb li+li::before{content:"/";margin-right:8px;color:rgba(38,239,208,.45)}

/* ===== 标签页 ===== */
.by-tabs{margin-block:clamp(20px,3vw,34px)}
.by-tablist{
  display:flex;
  flex-wrap:wrap;
  gap:4px;
  margin:0 0 20px;
  padding:0 0 10px;
  border-bottom:1px solid var(--by-line);
}
.by-tab{
  appearance:none;
  -webkit-appearance:none;
  padding:9px 15px;
  border:1px solid transparent;
  background:transparent;
  color:var(--by-mist);
  font:inherit;
  font-size:14px;
  font-weight:650;
  letter-spacing:.02em;
  cursor:pointer;
  transition:color .18s ease,background .18s ease,border-color .18s ease;
}
.by-tab:hover{color:var(--by-text);border-color:var(--by-line)}
.by-tab[aria-selected="true"]{
  color:var(--by-cyan);
  border-color:var(--by-line-strong);
  background:linear-gradient(180deg,rgba(38,239,208,.12),transparent);
}
.by-tabs__panels{position:relative}
.by-tabpanel:focus{outline:none}
.by-tabpanel[hidden]{display:none}

/* ===== 时间轴 / 更新日志 ===== */
.by-timeline{
  display:flex;
  flex-direction:column;
  gap:clamp(18px,2.6vw,30px);
  margin:0;
  padding:0 0 0 26px;
  list-style:none;
  border-left:1px solid var(--by-line);
}
.by-timeline__item{position:relative}
.by-timeline__item::before{
  content:"";
  position:absolute;
  left:-30px;
  top:8px;
  width:9px;
  height:9px;
  background:var(--by-cyan);
  box-shadow:0 0 0 4px rgba(38,239,208,.12);
}
.by-timeline__meta{
  margin:0 0 6px;
  font-family:var(--by-mono);
  font-size:11.5px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--by-orange);
}
.by-timeline__title{margin:0 0 6px;font-size:17px;font-weight:740;color:#fff}
.by-timeline__text{margin:0;font-size:15px;line-height:1.82;color:var(--by-silver)}

/* ===== 对照表 ===== */
.by-table__wrap{
  overflow-x:auto;
  border:1px solid var(--by-line);
  background:rgba(255,255,255,.015);
}
.by-table{
  width:100%;
  min-width:520px;
  border-collapse:collapse;
  font-size:14.5px;
}
.by-table th,
.by-table td{
  padding:13px 16px;
  text-align:left;
  vertical-align:top;
  border-bottom:1px solid var(--by-line);
}
.by-table thead th{
  font-family:var(--by-mono);
  font-size:11.5px;
  font-weight:650;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--by-cyan);
  background:rgba(38,239,208,.05);
}
.by-table tbody tr:hover{background:rgba(38,239,208,.045)}
.by-table tbody tr:last-child td{border-bottom:0}

/* ===== 页脚 ===== */
.by-footer{
  position:relative;
  margin-top:clamp(56px,9vw,120px);
  background:linear-gradient(180deg,var(--by-ink-2),#030b09);
  border-top:1px solid var(--by-line);
}
.by-footer::before{
  content:"";
  position:absolute;
  inset:0 0 auto;
  height:2px;
  background:linear-gradient(90deg,var(--by-cyan),var(--by-orange) 52%,transparent);
}
.by-footer__top{
  display:grid;
  grid-template-columns:minmax(0,1.5fr) repeat(2,minmax(0,.85fr)) minmax(0,1.15fr);
  gap:clamp(22px,3vw,48px);
  padding-block:clamp(38px,5vw,68px);
}
.by-footer__desc{
  max-width:38ch;
  margin:14px 0 0;
  font-size:14px;
  line-height:1.8;
  color:var(--by-mist);
}
.by-footer__title{
  margin:0 0 14px;
  font-family:var(--by-mono);
  font-size:11.5px;
  font-weight:650;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--by-cyan);
}
.by-footer__list{
  display:flex;
  flex-direction:column;
  gap:9px;
  margin:0;
  padding:0;
  list-style:none;
  font-size:14px;
}
.by-footer__link{
  color:var(--by-silver);
  text-decoration:none;
  transition:color .18s ease;
}
.by-footer__link:hover{color:var(--by-cyan)}
.by-footer__list--contact li{
  font-family:var(--by-mono);
  font-size:13px;
  line-height:1.7;
  color:var(--by-text);
  word-break:break-word;
}
.by-footer__label{
  display:block;
  margin-bottom:2px;
  font-family:var(--by-sans);
  font-size:11px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--by-mist);
}
.by-footer__note{margin:14px 0 0;font-size:12.5px;line-height:1.7;color:var(--by-mist)}
.by-footer__bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  padding-block:20px 30px;
  border-top:1px solid var(--by-line);
  font-family:var(--by-mono);
  font-size:12.5px;
  color:var(--by-mist);
}
.by-footer__copy{margin:0}
.by-footer__meta{display:flex;flex-wrap:wrap;align-items:center;gap:8px 18px;margin:0}
.by-footer__meta a{color:var(--by-silver);text-decoration:none}
.by-footer__meta a:hover{color:var(--by-cyan)}

/* ===== 头部与页脚响应式 ===== */
@media (max-width:1000px){
  .by-nav{
    position:absolute;
    left:0;
    right:0;
    top:100%;
    display:none;
    margin:0;
    padding:10px clamp(18px,4vw,40px) 22px;
    max-height:calc(100vh - 120px);
    overflow-y:auto;
    background:var(--by-jade);
    border-top:1px solid var(--by-line);
    border-bottom:1px solid var(--by-line);
    box-shadow:0 34px 60px -42px #000;
  }
  .by-header[data-open] .by-nav{display:block}
  .by-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .by-nav__link{padding:14px 2px;font-size:16px;border-bottom:1px solid var(--by-line)}
  .by-nav__link::after{display:none}
  .by-nav__link[aria-current="page"]{color:var(--by-cyan)}
  .by-nav__link[aria-current="page"]::before{
    content:"";
    position:absolute;
    left:0;
    top:50%;
    width:4px;
    height:18px;
    margin-top:-9px;
    background:var(--by-orange);
  }
  .by-burger{display:inline-flex}
}
@media (max-width:1040px){
  .by-footer__top{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:760px){
  .by-header__topin{font-size:12px}
  .by-header__barin{min-height:64px}
}
@media (max-width:640px){
  .by-header__cta{display:none}
  .by-header__note{max-width:24ch;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
  .by-footer__top{grid-template-columns:1fr;gap:28px}
  .by-footer__bottom{flex-direction:column;align-items:flex-start}
}