/* ============================================================
   乐鱼看台 · 共享 Site Kit
   swim-leyu-cn.com.cn
   技术蓝图网格 + 泳池看台意象
   ============================================================ */

:root{
  /* 品牌色 */
  --ly-blue:#0B63C5;
  --ly-blue-deep:#063A73;
  --ly-orange:#FF6A2B;
  --ly-orange-soft:#FFD9C7;
  --ly-green:#123B33;
  --ly-sand:#F3EEE4;
  --ly-paper:#FCFBF7;
  --ly-mist:#DCE8F5;
  --ly-ink:#101820;
  --ly-data:#2E8B6F;
  --ly-line:#A9B4C0;

  --ly-line-soft:rgba(169,180,192,.45);
  --ly-line-strong:rgba(169,180,192,.72);

  /* 字体 */
  --font-sans:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;

  /* 尺度 */
  --shell:1360px;
  --gutter:clamp(16px,4vw,48px);
  --radius:2px;
  --header-h:64px;
  --shadow-float:0 1px 0 rgba(16,24,32,.04),0 18px 40px -26px rgba(6,58,115,.5);
  --ease:cubic-bezier(.22,.61,.36,1);
}

@media (min-width:860px){
  :root{--header-h:76px}
}

/* ---------- Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--header-h) + 16px);
}
body{
  margin:0;
  padding-top:var(--header-h);
  background:var(--ly-paper);
  color:var(--ly-ink);
  font-family:var(--font-sans);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5,h6,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
a{color:var(--ly-blue);text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0}
table{border-collapse:collapse;width:100%}
::selection{background:var(--ly-orange-soft);color:var(--ly-blue-deep)}

/* ---------- 基础排版 ---------- */
h1,h2,h3,h4{font-weight:400;line-height:1.16;letter-spacing:-.015em;color:var(--ly-blue-deep)}
h1{font-size:clamp(2.25rem,5.6vw,4.25rem);font-weight:300}
h2{font-size:clamp(1.6rem,3vw,2.4rem);font-weight:300}
h3{font-size:clamp(1.15rem,1.8vw,1.5rem);font-weight:700;letter-spacing:-.005em;line-height:1.35}
h4{font-size:1.0625rem;font-weight:700;line-height:1.45}
p{max-width:34em}
strong{font-weight:700}
.mono{font-family:var(--font-mono);font-weight:500;font-variant-numeric:tabular-nums;letter-spacing:0}
.lede{max-width:32em;font-size:clamp(1rem,1.5vw,1.1875rem);line-height:1.8;color:#2b3540}

/* ---------- 跳转链接 ---------- */
.skip-link{
  position:fixed;
  top:8px;
  left:8px;
  z-index:400;
  transform:translateY(-180%);
  padding:10px 18px;
  background:var(--ly-ink);
  color:var(--ly-paper);
  font-size:14px;
  font-weight:500;
  border-radius:var(--radius);
  transition:transform .18s var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{transform:translateY(0);color:var(--ly-paper)}

/* ---------- 头部 ---------- */
.site-header{
  position:fixed;
  inset:0 0 auto 0;
  z-index:120;
  background:rgba(252,251,247,.96);
  border-bottom:1px solid transparent;
  transition:background .24s var(--ease),border-color .24s var(--ease),box-shadow .24s var(--ease);
}
@media (min-width:860px){
  .site-header{
    background:rgba(252,251,247,.8);
    -webkit-backdrop-filter:blur(14px) saturate(140%);
    backdrop-filter:blur(14px) saturate(140%);
    border-bottom-color:var(--ly-line-soft);
  }
}
.site-header[data-scrolled="true"]{
  background:rgba(252,251,247,.97);
  border-bottom-color:var(--ly-line-soft);
  box-shadow:0 14px 30px -28px rgba(6,58,115,.7);
}

.header-shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.header-bar{
  display:flex;
  align-items:center;
  gap:clamp(10px,2vw,28px);
  height:var(--header-h);
}

/* 品牌 */
.brand{
  display:flex;
  align-items:center;
  gap:10px;
  flex:0 0 auto;
  color:var(--ly-blue-deep);
}
.brand-mark{
  position:relative;
  flex:0 0 auto;
  width:30px;
  height:30px;
  border:1px solid var(--ly-blue-deep);
  background-image:repeating-linear-gradient(180deg,var(--ly-blue) 0 2px,transparent 2px 8px);
  background-color:var(--ly-paper);
}
.brand-mark::after{
  content:"";
  position:absolute;
  right:-3px;
  bottom:-3px;
  width:8px;
  height:8px;
  background:var(--ly-orange);
}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-name{font-size:1.0625rem;font-weight:700;letter-spacing:.02em;color:var(--ly-blue-deep)}
.brand-sub{
  margin-top:3px;
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:.22em;
  color:var(--ly-blue);
}

/* 速览数据条 */
.quick-strip{display:none}
@media (min-width:1180px){
  .quick-strip{display:flex;align-items:center;min-width:0;margin-right:auto}
  .quick-item{
    display:flex;
    align-items:baseline;
    gap:.45em;
    padding-left:16px;
    margin-left:16px;
    border-left:1px solid var(--ly-line-soft);
    white-space:nowrap;
  }
  .quick-item:first-child{border-left:0;padding-left:0;margin-left:0}
}
.quick-k{
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:.16em;
  color:var(--ly-blue);
}
.quick-v{font-size:12px;font-weight:500;color:var(--ly-blue-deep)}
.quick-v--accent{color:var(--ly-orange)}

/* 移动端导航按钮 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:9px;
  margin-left:auto;
  padding:9px 15px;
  border:1px solid var(--ly-line-strong);
  border-radius:999px;
  background:var(--ly-paper);
  color:var(--ly-blue-deep);
  font-size:13px;
  font-weight:500;
  letter-spacing:.04em;
  cursor:pointer;
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--ly-blue);color:var(--ly-blue)}
.nav-toggle-label{line-height:1}
.nav-toggle-bars{
  display:inline-flex;
  flex-direction:column;
  justify-content:center;
  gap:5px;
  width:16px;
  height:11px;
}
.nav-toggle-bars i{
  display:block;
  height:1.5px;
  background:currentColor;
  transition:transform .22s var(--ease),opacity .22s var(--ease);
}
.site-header[data-open="true"] .nav-toggle-bars i:first-child{transform:translateY(3.25px) rotate(45deg)}
.site-header[data-open="true"] .nav-toggle-bars i:last-child{transform:translateY(-3.25px) rotate(-45deg)}

/* 胶囊导航 */
.site-nav{
  display:flex;
  align-items:center;
  gap:6px;
  margin-left:auto;
  padding:5px;
  border:1px solid var(--ly-line-soft);
  border-radius:999px;
  background:rgba(252,251,247,.92);
  box-shadow:var(--shadow-float);
}
.nav-list{display:flex;align-items:center;gap:2px}
.nav-link{
  display:block;
  padding:8px 14px;
  border-radius:999px;
  font-size:14px;
  font-weight:500;
  line-height:1.3;
  color:var(--ly-blue-deep);
  white-space:nowrap;
  transition:background .18s var(--ease),color .18s var(--ease);
}
.nav-link:hover{background:var(--ly-mist);color:var(--ly-blue)}
.nav-link[aria-current="page"]{
  background:var(--ly-orange-soft);
  color:var(--ly-blue-deep);
  font-weight:700;
}
.nav-link[aria-current="page"]::before{
  content:"";
  display:inline-block;
  width:6px;
  height:6px;
  margin-right:7px;
  border-radius:50%;
  background:var(--ly-orange);
  vertical-align:middle;
  transform:translateY(-1px);
}
.nav-cta{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:9px 18px;
  border-radius:999px;
  background:var(--ly-blue);
  color:#fff;
  font-size:14px;
  font-weight:500;
  line-height:1.3;
  white-space:nowrap;
  transition:background .2s var(--ease),color .2s var(--ease);
}
.nav-cta::before{
  content:"";
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--ly-orange);
  box-shadow:0 0 0 3px rgba(255,106,43,.24);
}
.nav-cta:hover{background:var(--ly-blue-deep);color:#fff}

/* 阅读进度 */
.scroll-meter{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  height:2px;
  overflow:hidden;
  pointer-events:none;
}
.scroll-bar{
  display:block;
  width:100%;
  height:100%;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--ly-blue) 0%,var(--ly-blue) 55%,var(--ly-orange) 100%);
  transition:transform .15s linear;
}

/* 移动端：导航收为底部浮岛 */
@media (max-width:859.98px){
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:fixed;
    left:12px;
    right:12px;
    bottom:12px;
    z-index:130;
    flex-direction:column;
    align-items:stretch;
    gap:10px;
    margin-left:0;
    padding:12px;
    border-radius:18px;
    border-color:var(--ly-line-soft);
    background:rgba(252,251,247,.98);
    box-shadow:0 26px 60px -26px rgba(6,58,115,.6);
    transform:translateY(calc(100% + 32px));
    opacity:0;
    visibility:hidden;
    pointer-events:none;
    transition:transform .28s var(--ease),opacity .2s var(--ease),visibility .28s;
  }
  .site-header[data-open="true"] .site-nav{
    transform:translateY(0);
    opacity:1;
    visibility:visible;
    pointer-events:auto;
  }
  .nav-list{display:grid;grid-template-columns:1fr 1fr;gap:4px}
  .nav-link{padding:11px 12px;border-radius:10px;font-size:14px}
  .nav-link[aria-current="page"]{border-radius:10px}
  .nav-cta{justify-content:center;border-radius:10px;padding:12px 16px}
}

/* ---------- 页脚 ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(48px,8vw,120px);
  background:var(--ly-green);
  color:var(--ly-sand);
  overflow:hidden;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    repeating-linear-gradient(180deg,rgba(243,238,228,.07) 0 1px,transparent 1px 56px),
    repeating-linear-gradient(90deg,rgba(243,238,228,.05) 0 1px,transparent 1px 56px);
  -webkit-mask-image:linear-gradient(180deg,rgba(0,0,0,.95),transparent 78%);
  mask-image:linear-gradient(180deg,rgba(0,0,0,.95),transparent 78%);
}
.footer-inner{
  position:relative;
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding:clamp(40px,6vw,80px) var(--gutter) clamp(20px,3vw,32px);
}
.footer-top{
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:clamp(28px,4vw,56px);
  padding-bottom:clamp(26px,4vw,48px);
  border-bottom:1px solid rgba(243,238,228,.18);
}
@media (min-width:1000px){
  .footer-top{grid-template-columns:minmax(0,1.1fr) minmax(0,1.9fr);gap:clamp(32px,5vw,88px)}
}
.footer-brand{min-width:0}
.footer-wordmark{
  font-size:clamp(30px,4.4vw,54px);
  font-weight:300;
  line-height:1.06;
  letter-spacing:-.02em;
  color:var(--ly-paper);
  max-width:none;
}
.footer-wordmark span{
  display:inline-block;
  margin:0 .12em;
  color:var(--ly-orange);
  font-weight:300;
}
.footer-summary{
  max-width:34ch;
  margin-top:16px;
  font-size:15px;
  line-height:1.85;
  color:rgba(243,238,228,.78);
}
.footer-contact{
  display:grid;
  gap:9px;
  margin-top:clamp(22px,3vw,34px);
  padding-top:clamp(18px,2.4vw,26px);
  border-top:1px solid rgba(243,238,228,.16);
}
.contact-row{
  display:grid;
  grid-template-columns:44px minmax(0,1fr);
  gap:12px;
  align-items:baseline;
  font-size:14px;
}
.contact-k{
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:.16em;
  color:rgba(243,238,228,.5);
}
.contact-v{
  min-width:0;
  color:rgba(243,238,228,.9);
  font-size:13.5px;
  line-height:1.6;
  word-break:break-word;
}
.contact-v.mono{letter-spacing:.01em}

.footer-cols{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:clamp(18px,3vw,40px);
}
@media (max-width:559.98px){
  .footer-cols{grid-template-columns:repeat(2,minmax(0,1fr))}
}
.footer-col{min-width:0}
.footer-col-title{
  padding-bottom:10px;
  margin-bottom:14px;
  border-bottom:1px solid rgba(243,238,228,.2);
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:.26em;
  color:rgba(243,238,228,.55);
  line-height:1.4;
}
.footer-links li + li{margin-top:9px}
.footer-link{
  display:inline-block;
  font-size:14px;
  line-height:1.6;
  color:var(--ly-sand);
  transition:color .18s var(--ease),transform .18s var(--ease);
}
.footer-link:hover,
.footer-link:focus-visible{color:var(--ly-orange-soft);transform:translateX(2px)}

.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:12px 24px;
  padding-top:clamp(18px,2.4vw,26px);
}
.footer-legal{
  max-width:none;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:rgba(243,238,228,.62);
}
.footer-note{
  flex:1 1 260px;
  max-width:56ch;
  font-size:12.5px;
  line-height:1.7;
  color:rgba(243,238,228,.55);
}
.to-top{
  margin-left:auto;
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:10px 16px;
  border:1px solid rgba(243,238,228,.26);
  border-radius:999px;
  background:transparent;
  color:var(--ly-sand);
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.12em;
  cursor:pointer;
  transition:background .2s var(--ease),border-color .2s var(--ease),color .2s var(--ease);
}
.to-top:hover{background:var(--ly-orange);border-color:var(--ly-orange);color:var(--ly-ink)}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:13px 22px;
  border:1px solid transparent;
  border-radius:var(--radius);
  font-family:var(--font-sans);
  font-size:15px;
  font-weight:500;
  line-height:1.2;
  text-align:center;
  cursor:pointer;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease),transform .2s var(--ease);
}
.btn--primary{background:var(--ly-blue);color:#fff}
.btn--primary:hover{background:var(--ly-blue-deep);color:#fff}
.btn--accent{background:var(--ly-orange);color:var(--ly-ink)}
.btn--accent:hover{background:var(--ly-orange-soft);color:var(--ly-blue-deep)}
.btn--ghost{background:transparent;border-color:var(--ly-line-strong);color:var(--ly-blue-deep)}
.btn--ghost:hover{background:var(--ly-mist);border-color:var(--ly-blue);color:var(--ly-blue)}
.btn--on-dark{background:transparent;border-color:rgba(243,238,228,.42);color:var(--ly-sand)}
.btn--on-dark:hover{background:rgba(243,238,228,.12);color:var(--ly-paper)}

/* ---------- 面包屑 ---------- */
.breadcrumb{
  padding-top:clamp(18px,3vw,34px);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--ly-blue);
}
.breadcrumb-list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
}
.breadcrumb-item{display:flex;align-items:center;gap:8px;min-width:0}
.breadcrumb-item + .breadcrumb-item::before{
  content:"/";
  color:var(--ly-line);
  font-weight:400;
}
.breadcrumb-link{color:var(--ly-blue)}
.breadcrumb-link:hover{color:var(--ly-orange)}
.breadcrumb-current{color:var(--ly-blue-deep);font-weight:500}

/* ---------- 布局骨架 ---------- */
.container{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{padding-block:clamp(40px,6vw,88px)}
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--grid-gap,24px);
}
@media (max-width:899.98px){
  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr));gap:var(--grid-gap,16px)}
}
@media (max-width:599.98px){
  .grid-12{grid-template-columns:repeat(2,minmax(0,1fr))}
}

/* ---------- 内容组件 ---------- */
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.2em;
  color:var(--ly-blue);
  text-transform:uppercase;
}
.eyebrow::before{
  content:"";
  flex:0 0 auto;
  width:18px;
  height:1px;
  background:var(--ly-orange);
}
.index-tag{
  display:inline-block;
  padding:3px 8px;
  border:1px solid var(--ly-line-soft);
  background:var(--ly-mist);
  color:var(--ly-blue-deep);
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.14em;
  line-height:1.5;
}
.card{
  padding:clamp(18px,2.4vw,28px);
  border:1px solid var(--ly-line-soft);
  border-radius:var(--radius);
  background:var(--ly-paper);
}
.card--sand{background:var(--ly-sand)}
.card--mist{background:var(--ly-mist)}
.card--ink{
  background:var(--ly-blue-deep);
  border-color:transparent;
  color:var(--ly-paper);
}
.card--ink h2,.card--ink h3,.card--ink h4{color:var(--ly-paper)}
.panel{
  padding:clamp(20px,3vw,36px);
  border:1px solid var(--ly-line-soft);
  border-radius:var(--radius);
  background:var(--ly-sand);
}
.stat{display:grid;gap:6px;align-content:start}
.stat-value{
  font-family:var(--font-mono);
  font-size:clamp(26px,3.4vw,40px);
  font-weight:500;
  line-height:1;
  letter-spacing:-.01em;
  font-variant-numeric:tabular-nums;
  color:var(--ly-blue-deep);
}
.stat-label{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.16em;
  color:var(--ly-blue);
}
.divider{
  height:1px;
  margin-block:clamp(24px,4vw,48px);
  border:0;
  background:var(--ly-line-soft);
}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border:1px solid var(--ly-line-soft);
  border-radius:999px;
  background:var(--ly-paper);
  color:var(--ly-blue-deep);
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.08em;
  line-height:1.6;
}
.tag--accent{background:var(--ly-orange-soft);border-color:var(--ly-orange-soft)}
.tag--data{background:rgba(46,139,111,.12);border-color:rgba(46,139,111,.42);color:#1f6b52}

/* 图片容器（页面阶段放入 <img>） */
.media-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:16 / 10;
  border:1px solid var(--ly-line-soft);
  border-radius:var(--radius);
  background:var(--ly-mist);
}
.media-frame img,
.media-frame video{
  width:100%;
  height:100%;
  object-fit:cover;
}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:4 / 5}
.media-frame--square{aspect-ratio:1 / 1}

/* ---------- 工具 ---------- */
.sr-only{
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip:rect(0 0 0 0);
  clip-path:inset(50%);
  white-space:nowrap;
  border:0;
}
#main-content:focus{outline:none}

/* ---------- 焦点 ---------- */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible{
  outline:2px solid var(--ly-orange);
  outline-offset:3px;
  border-radius:2px;
}
.site-footer a:focus-visible,
.site-footer button:focus-visible{outline-color:var(--ly-orange-soft)}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .scroll-bar{transition:none}
  .footer-link:hover,.footer-link:focus-visible{transform:none}
}