/* ============================================================
   9博主页 · 共享 Site Kit  /assets/site.css
   ============================================================ */

/* ---------- 1. 设计变量 ---------- */
:root{
  --abyss:#04121F;
  --midnight:#0A2540;
  --harbor:#0F3B4C;
  --signal:#35F2D0;
  --mist:#B8FFF2;
  --amber:#FF8A3D;
  --magenta:#E94FA1;
  --fog:#EAF4F7;
  --steel:#7C93A6;
  --ink:#0B2E38;
  --lime:#9CFF57;

  --grad-deep:linear-gradient(152deg,#123A5A 0%,#0A2540 68%,#08203A 100%);
  --grad-signal:linear-gradient(135deg,#35F2D0 0%,#48D6E8 100%);
  --line:rgba(124,147,166,.24);
  --line-strong:rgba(184,255,242,.34);

  --font-display:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-condensed:"Barlow Condensed","Oswald","Roboto Condensed","Arial Narrow",system-ui,sans-serif;
  --font-serif:"Noto Serif SC","Source Han Serif SC","Songti SC","STSong",serif;

  --header-h:68px;
  --shell-max:1280px;
  --gutter:48px;

  --radius-lg:26px;
  --radius-md:18px;
  --radius-sm:12px;
  --radius-pill:999px;

  --ease:cubic-bezier(.22,.68,.26,1);
  --dur-fast:150ms;
  --dur:220ms;
}

/* ---------- 2. Reset ---------- */
*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
body{
  margin:0;
  background-color:var(--abyss);
  background-image:radial-gradient(900px 480px at 88% -8%,rgba(18,58,90,.6),transparent 68%);
  background-repeat:no-repeat;
  color:var(--fog);
  font-family:var(--font-body);
  font-size:17px;
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5,h6{margin:0;font-family:var(--font-display);font-weight:900;line-height:1.15;letter-spacing:-.01em;color:var(--fog);}
p{margin:0;}
ul,ol{margin:0;padding:0;list-style:none;}
dl,dd{margin:0;}
img,svg,video{display:block;max-width:100%;}
a{color:var(--signal);text-decoration:none;}
button,input,select,textarea{font:inherit;color:inherit;}
button{background:none;border:0;padding:0;}
[hidden]{display:none !important;}
::selection{background:rgba(53,242,208,.32);color:#FFFFFF;}
:focus-visible{outline:2px solid var(--signal);outline-offset:3px;border-radius:6px;}

/* ---------- 3. 布局外壳 ---------- */
.shell{
  width:100%;
  max-width:calc(var(--shell-max) + var(--gutter) * 2);
  margin-inline:auto;
  padding-inline:var(--gutter);
}

.skip-link{
  position:absolute;
  left:16px;
  top:-120px;
  z-index:200;
  display:inline-flex;
  align-items:center;
  padding:12px 22px;
  border-radius:var(--radius-pill);
  background:var(--signal);
  color:#03151A;
  font-family:var(--font-display);
  font-weight:700;
  font-size:14px;
  transition:top var(--dur) var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{top:16px;outline-offset:2px;}

/* ---------- 4. 页头 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:transparent;
  border-bottom:1px solid transparent;
  transition:background var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.site-header.is-scrolled{
  background:rgba(10,37,64,.94);
  border-bottom-color:var(--line);
  box-shadow:0 20px 44px -34px rgba(0,0,0,.95);
  -webkit-backdrop-filter:blur(14px) saturate(150%);
  backdrop-filter:blur(14px) saturate(150%);
}
.header-shell{
  position:relative;
  display:flex;
  align-items:center;
  gap:20px;
  min-height:var(--header-h);
  padding-block:8px;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:11px;
  flex:0 0 auto;
  color:var(--fog);
  text-decoration:none;
}
.brand-mark{
  display:grid;
  place-items:center;
  width:38px;
  height:38px;
  border-radius:12px;
  background:var(--grad-signal);
  color:#03151A;
  font-family:var(--font-condensed);
  font-weight:600;
  font-size:23px;
  line-height:1;
  box-shadow:0 0 0 1px rgba(53,242,208,.45),0 10px 24px -14px rgba(53,242,208,.95);
  transition:transform var(--dur) var(--ease);
}
.brand:hover .brand-mark{transform:rotate(-6deg) scale(1.04);}
.brand-text{display:flex;flex-direction:column;gap:2px;line-height:1.1;}
.brand-label{font-family:var(--font-display);font-weight:900;font-size:17px;letter-spacing:.02em;color:var(--fog);}
.brand-sub{font-family:var(--font-serif);font-weight:600;font-size:10.5px;letter-spacing:.16em;color:var(--steel);}

.site-nav{display:flex;align-items:center;gap:16px;margin-left:auto;}
.nav-list{display:flex;align-items:center;gap:2px;}
.nav-link{
  display:inline-flex;
  align-items:baseline;
  gap:6px;
  padding:9px 12px;
  border-radius:var(--radius-pill);
  color:rgba(234,244,247,.76);
  font-size:14.5px;
  font-weight:500;
  white-space:nowrap;
  transition:color var(--dur-fast) var(--ease),background var(--dur-fast) var(--ease),box-shadow var(--dur-fast) var(--ease);
}
.nav-index{
  font-family:var(--font-serif);
  font-size:10.5px;
  font-weight:600;
  letter-spacing:.04em;
  color:rgba(124,147,166,.85);
  transition:color var(--dur-fast) var(--ease);
}
.nav-link:hover{color:var(--mist);background:rgba(53,242,208,.09);}
.nav-link:hover .nav-index{color:var(--signal);}
.nav-link[aria-current="page"]{
  color:var(--mist);
  background:rgba(53,242,208,.13);
  box-shadow:inset 0 0 0 1px rgba(53,242,208,.42);
}
.nav-link[aria-current="page"] .nav-index{color:var(--signal);}
.nav-cta{flex:0 0 auto;}

.nav-toggle{
  display:none;
  align-items:center;
  gap:9px;
  margin-left:auto;
  padding:9px 15px 9px 13px;
  border-radius:var(--radius-pill);
  border:1px solid var(--line-strong);
  background:rgba(53,242,208,.08);
  color:var(--mist);
  cursor:pointer;
  transition:background var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease);
}
.nav-toggle:hover{background:rgba(53,242,208,.16);border-color:var(--signal);}
.nav-toggle-icon{display:flex;flex-direction:column;justify-content:center;gap:4px;width:16px;}
.nav-toggle-bar{
  display:block;
  width:16px;
  height:2px;
  border-radius:2px;
  background:var(--signal);
  transition:transform var(--dur) var(--ease),opacity var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(3px) rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){transform:translateY(-3px) rotate(-45deg);}
.nav-toggle-label{font-family:var(--font-display);font-weight:700;font-size:13px;letter-spacing:.08em;}

.scroll-meter{position:absolute;left:0;right:0;bottom:0;height:2px;overflow:hidden;pointer-events:none;}
.scroll-meter-fill{
  display:block;
  width:100%;
  height:100%;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--signal) 0%,var(--lime) 100%);
  transition:transform 120ms linear;
}

/* ---------- 5. 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:12px 22px;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  font-family:var(--font-display);
  font-weight:700;
  font-size:14.5px;
  letter-spacing:.02em;
  line-height:1.2;
  text-decoration:none;
  cursor:pointer;
  transition:transform var(--dur-fast) var(--ease),background var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease),box-shadow var(--dur-fast) var(--ease),color var(--dur-fast) var(--ease);
}
.btn:hover{transform:translateY(-2px);}
.btn:active{transform:translateY(0);}
.btn--signal{background:var(--signal);color:#03151A;box-shadow:0 12px 28px -16px rgba(53,242,208,.95);}
.btn--signal:hover{background:var(--mist);box-shadow:0 18px 34px -16px rgba(53,242,208,.8);}
.btn--ghost{background:rgba(53,242,208,.07);border-color:var(--line-strong);color:var(--mist);}
.btn--ghost:hover{background:rgba(53,242,208,.15);border-color:var(--signal);}
.btn--amber{background:var(--amber);color:#22100A;box-shadow:0 12px 28px -18px rgba(255,138,61,.95);}
.btn--amber:hover{background:#FFA063;}
.btn--wide{width:100%;}

/* ---------- 6. 页脚 ---------- */
.site-footer{
  position:relative;
  margin-top:88px;
  padding-top:64px;
  background:var(--ink);
  border-top:1px solid var(--line);
  overflow:hidden;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:-1px 0 auto 0;
  height:300px;
  pointer-events:none;
  background:
    radial-gradient(680px 260px at 12% 0%,rgba(53,242,208,.13),transparent 72%),
    radial-gradient(520px 220px at 88% 0%,rgba(233,79,161,.10),transparent 70%);
}
.footer-grid{
  position:relative;
  display:grid;
  grid-template-columns:minmax(0,1.5fr) minmax(0,.9fr) minmax(0,.9fr) minmax(0,1.4fr);
  gap:48px 40px;
  padding-bottom:56px;
}
.footer-summary{
  margin-top:18px;
  max-width:34ch;
  font-size:14.5px;
  line-height:1.8;
  color:rgba(234,244,247,.72);
}
.footer-chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:20px;}
.chip{
  display:inline-flex;
  align-items:center;
  padding:5px 12px;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  font-family:var(--font-condensed);
  font-size:12.5px;
  font-weight:600;
  letter-spacing:.06em;
}
.chip--signal{background:rgba(53,242,208,.14);color:var(--mist);border-color:rgba(53,242,208,.36);}
.chip--amber{background:rgba(255,138,61,.15);color:#FFC49A;border-color:rgba(255,138,61,.36);}
.chip--magenta{background:rgba(233,79,161,.15);color:#FFA8D4;border-color:rgba(233,79,161,.36);}

.footer-title{
  margin-bottom:16px;
  font-family:var(--font-display);
  font-size:12.5px;
  font-weight:700;
  letter-spacing:.16em;
  color:var(--steel);
}
.footer-links{display:flex;flex-direction:column;gap:10px;}
.footer-links a{
  position:relative;
  display:inline-block;
  color:rgba(234,244,247,.78);
  font-size:14.5px;
  transition:color var(--dur-fast) var(--ease),transform var(--dur-fast) var(--ease);
}
.footer-links a::before{
  content:"";
  position:absolute;
  left:-14px;
  top:50%;
  width:6px;
  height:1px;
  background:var(--signal);
  opacity:0;
  transform:translateX(-4px);
  transition:opacity var(--dur-fast) var(--ease),transform var(--dur-fast) var(--ease);
}
.footer-links a:hover{color:var(--signal);transform:translateX(4px);}
.footer-links a:hover::before{opacity:1;transform:translateX(0);}

.footer-contact{display:flex;flex-direction:column;gap:12px;}
.contact-row{display:grid;grid-template-columns:42px minmax(0,1fr);gap:10px;align-items:baseline;}
.contact-key{font-family:var(--font-serif);font-size:11.5px;font-weight:600;letter-spacing:.12em;color:var(--steel);}
.contact-val{
  font-family:var(--font-body);
  font-size:14.5px;
  line-height:1.6;
  color:rgba(234,244,247,.9);
  word-break:break-word;
}
.footer-note{margin-top:16px;font-size:13px;line-height:1.7;color:rgba(124,147,166,.95);}
.copy-btn{
  margin-top:14px;
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:8px 16px;
  border-radius:var(--radius-pill);
  border:1px solid var(--line-strong);
  background:rgba(53,242,208,.07);
  color:var(--mist);
  font-family:var(--font-display);
  font-weight:700;
  font-size:13px;
  cursor:pointer;
  transition:background var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease),color var(--dur-fast) var(--ease);
}
.copy-btn:hover{background:rgba(53,242,208,.16);border-color:var(--signal);}
.copy-btn.is-copied{background:var(--signal);border-color:var(--signal);color:#03151A;}

.footer-base{
  position:relative;
  display:flex;
  align-items:center;
  justify-content:space-between;
  flex-wrap:wrap;
  gap:16px;
  padding-block:20px 26px;
  border-top:1px solid rgba(124,147,166,.18);
  font-size:12.5px;
  color:rgba(124,147,166,.9);
}
.footer-copy{font-family:var(--font-body);}
.footer-icp{font-family:var(--font-condensed);letter-spacing:.06em;}

.to-top{
  position:fixed;
  right:22px;
  bottom:22px;
  z-index:70;
  display:grid;
  place-items:center;
  width:46px;
  height:46px;
  border-radius:50%;
  border:1px solid rgba(53,242,208,.4);
  background:rgba(10,37,64,.92);
  color:var(--signal);
  font-size:17px;
  line-height:1;
  cursor:pointer;
  opacity:0;
  visibility:hidden;
  transform:translateY(12px);
  box-shadow:0 18px 34px -22px rgba(0,0,0,.95);
  transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease),visibility var(--dur) var(--ease),background var(--dur-fast) var(--ease);
}
.to-top[data-visible]{opacity:1;visibility:visible;transform:none;}
.to-top:hover{background:rgba(53,242,208,.18);}

/* ---------- 7. 版式区块 ---------- */
.section{padding-block:72px;}
.section--tight{padding-block:44px;}
.section-head{
  display:flex;
  align-items:flex-end;
  justify-content:space-between;
  flex-wrap:wrap;
  gap:24px;
  margin-bottom:30px;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-serif);
  font-weight:600;
  font-size:12.5px;
  letter-spacing:.2em;
  color:var(--signal);
}
.eyebrow::before{content:"";width:24px;height:1px;background:currentColor;opacity:.7;}
.section-title{font-size:clamp(26px,3.2vw,38px);margin-top:8px;}
.section-sub{max-width:52ch;margin-top:10px;font-size:15.5px;line-height:1.8;color:rgba(234,244,247,.7);}
.lede{max-width:62ch;font-size:clamp(17px,1.6vw,20px);line-height:1.8;color:rgba(234,244,247,.82);}

.page-head{padding-block:8px 36px;}
.page-title{font-size:clamp(32px,4.4vw,54px);line-height:1.08;margin-top:14px;letter-spacing:-.02em;}
.page-desc{max-width:60ch;margin-top:16px;font-size:16px;line-height:1.8;color:rgba(234,244,247,.72);}

.prose{max-width:72ch;font-size:16.5px;line-height:1.85;color:rgba(234,244,247,.84);}
.prose > * + *{margin-top:18px;}
.prose h2{margin-top:40px;font-size:clamp(22px,2.4vw,28px);}
.prose h3{margin-top:28px;font-size:19px;}
.prose ul,.prose ol{padding-left:1.3em;list-style:disc;}
.prose ol{list-style:decimal;}
.prose li + li{margin-top:8px;}
.prose a{color:var(--signal);text-decoration:underline;text-underline-offset:3px;text-decoration-thickness:1px;}
.prose blockquote{
  margin:28px 0;
  padding:16px 22px;
  border-left:2px solid var(--signal);
  border-radius:0 var(--radius-sm) var(--radius-sm) 0;
  background:rgba(53,242,208,.06);
  font-family:var(--font-serif);
  color:var(--mist);
}
.prose code{
  font-family:var(--font-condensed);
  font-size:.96em;
  padding:2px 6px;
  border-radius:6px;
  background:rgba(53,242,208,.1);
  color:var(--mist);
}

/* ---------- 8. 面包屑 ---------- */
.breadcrumbs{padding-block:18px 0;}
.breadcrumbs ol{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:12.5px;color:var(--steel);}
.crumb{display:inline-flex;align-items:center;}
.crumb a{color:rgba(234,244,247,.7);transition:color var(--dur-fast) var(--ease);}
.crumb a:hover{color:var(--signal);}
.crumb[aria-current="page"]{color:var(--fog);}
.crumb-sep{color:rgba(124,147,166,.45);}

/* ---------- 9. 网格 ---------- */
.grid{display:grid;gap:24px;}
.grid--12{grid-template-columns:repeat(12,minmax(0,1fr));}
.grid--split{grid-template-columns:minmax(0,7fr) minmax(0,5fr);}
.grid--catalog{grid-template-columns:minmax(0,3fr) minmax(0,9fr);align-items:start;}
.grid--cards{grid-template-columns:repeat(auto-fit,minmax(250px,1fr));}

/* ---------- 10. 卡片 ---------- */
.card{
  position:relative;
  display:flex;
  flex-direction:column;
  gap:10px;
  padding:24px 26px;
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  background:linear-gradient(158deg,rgba(15,59,76,.72) 0%,rgba(10,37,64,.86) 62%,rgba(8,32,58,.9) 100%);
  transition:transform var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.card:hover{transform:translateY(-3px);border-color:rgba(53,242,208,.38);box-shadow:0 26px 50px -34px rgba(0,0,0,.95);}
.card--flush{padding:0;overflow:hidden;}
.card--accent{border-left:2px solid var(--signal);}
.card-eyebrow{font-family:var(--font-serif);font-weight:600;font-size:11.5px;letter-spacing:.18em;color:var(--signal);}
.card-title{font-family:var(--font-display);font-weight:900;font-size:20px;line-height:1.3;}
.card-title a{color:inherit;}
.card-title a:hover{color:var(--mist);}
.card-text{font-size:14.5px;line-height:1.8;color:rgba(234,244,247,.72);}
.card-meta{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px;
  margin-top:auto;
  padding-top:8px;
  font-family:var(--font-condensed);
  font-size:12.5px;
  letter-spacing:.06em;
  color:var(--steel);
}
.meta-dot{width:4px;height:4px;border-radius:50%;background:rgba(124,147,166,.7);}

/* ---------- 11. 标签与筛选 ---------- */
.tag-cloud{display:flex;flex-wrap:wrap;gap:8px;}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:7px 14px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(53,242,208,.24);
  background:rgba(53,242,208,.08);
  color:var(--mist);
  font-size:12.5px;
  font-weight:500;
  letter-spacing:.02em;
  cursor:pointer;
  transition:background var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease),color var(--dur-fast) var(--ease),transform var(--dur-fast) var(--ease);
}
.tag:hover{background:rgba(53,242,208,.18);border-color:var(--signal);transform:translateY(-1px);}
.tag--amber{border-color:rgba(255,138,61,.3);background:rgba(255,138,61,.1);color:#FFC49A;}
.tag--amber:hover{background:rgba(255,138,61,.2);border-color:var(--amber);}
.tag--magenta{border-color:rgba(233,79,161,.3);background:rgba(233,79,161,.1);color:#FFA8D4;}
.tag--magenta:hover{background:rgba(233,79,161,.2);border-color:var(--magenta);}
.tag--plain{border-color:var(--line);background:rgba(124,147,166,.08);color:rgba(234,244,247,.8);}
.tag.is-active,.tag[aria-pressed="true"]{background:var(--signal);border-color:var(--signal);color:#03151A;}

.filter-bar{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding:12px;
  border:1px solid var(--line);
  border-radius:var(--radius-pill);
  background:rgba(10,37,64,.66);
}
.filter-btn{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:8px 16px;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  background:transparent;
  color:rgba(234,244,247,.76);
  font-family:var(--font-display);
  font-weight:500;
  font-size:13px;
  white-space:nowrap;
  cursor:pointer;
  transition:background var(--dur-fast) var(--ease),color var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease);
}
.filter-btn:hover{color:var(--mist);background:rgba(53,242,208,.1);}
.filter-btn[aria-pressed="true"]{background:var(--signal);border-color:var(--signal);color:#03151A;font-weight:700;}
.filter-empty{
  padding:22px;
  border:1px dashed var(--line-strong);
  border-radius:var(--radius-md);
  color:var(--steel);
  font-size:14px;
  text-align:center;
}

/* ---------- 12. 可展开内容组 ---------- */
.disclosure{
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  background:rgba(10,37,64,.58);
  overflow:hidden;
  transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease);
}
.disclosure + .disclosure{margin-top:12px;}
.disclosure[data-open]{border-color:rgba(53,242,208,.4);background:rgba(15,59,76,.6);}
.disclosure-btn{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:18px;
  width:100%;
  padding:18px 22px;
  color:var(--fog);
  font-family:var(--font-display);
  font-weight:700;
  font-size:16.5px;
  line-height:1.4;
  text-align:left;
  cursor:pointer;
}
.disclosure-icon{
  flex:0 0 auto;
  display:grid;
  place-items:center;
  width:26px;
  height:26px;
  border-radius:50%;
  border:1px solid rgba(53,242,208,.35);
  color:var(--signal);
  font-size:15px;
  line-height:1;
  transition:transform var(--dur) var(--ease),background var(--dur) var(--ease),color var(--dur) var(--ease);
}
.disclosure[data-open] .disclosure-icon{transform:rotate(45deg);background:var(--signal);color:#03151A;}
.disclosure-panel{display:grid;grid-template-rows:0fr;transition:grid-template-rows var(--dur) var(--ease);}
.disclosure-panel > .disclosure-body{overflow:hidden;min-height:0;}
.disclosure[data-open] .disclosure-panel{grid-template-rows:1fr;}
.disclosure-body-inner{padding:0 22px 20px;font-size:14.5px;line-height:1.8;color:rgba(234,244,247,.76);}

/* ---------- 13. 时间轴 / 更新日志 ---------- */
.timeline{
  display:flex;
  flex-direction:column;
  gap:20px;
  padding-left:24px;
  border-left:1px solid rgba(124,147,166,.3);
}
.timeline-item{position:relative;}
.timeline-item::before{
  content:"";
  position:absolute;
  left:-28px;
  top:7px;
  width:9px;
  height:9px;
  border-radius:50%;
  background:var(--signal);
  box-shadow:0 0 0 4px rgba(53,242,208,.14);
}
.timeline-label{font-family:var(--font-condensed);font-size:12.5px;letter-spacing:.12em;color:var(--signal);}
.timeline-title{margin-top:4px;font-family:var(--font-display);font-weight:700;font-size:16px;}
.timeline-text{margin-top:4px;font-size:14px;line-height:1.75;color:rgba(234,244,247,.72);}

/* ---------- 14. 图片容器（供页面阶段放置占位） ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:16 / 9;
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  background:var(--grad-deep);
}
.media-frame > picture{display:block;width:100%;height:100%;}
.media-frame > img,
.media-frame > picture > img{width:100%;height:100%;object-fit:cover;}
.media-frame--wide{aspect-ratio:21 / 9;}
.media-frame--square{aspect-ratio:1 / 1;}
.media-frame--tall{aspect-ratio:4 / 5;}
.media-frame[data-placeholder]::after{
  content:attr(data-placeholder);
  position:absolute;
  inset:auto 0 0 0;
  padding:14px 18px;
  font-family:var(--font-condensed);
  font-size:12px;
  letter-spacing:.1em;
  color:rgba(184,255,242,.65);
  background:linear-gradient(0deg,rgba(4,18,31,.75),transparent);
}
.media-caption{margin-top:10px;font-size:12.5px;line-height:1.65;color:var(--steel);}

/* ---------- 15. 工具类 ---------- */
.num{font-family:var(--font-condensed);font-weight:600;font-variant-numeric:tabular-nums;letter-spacing:.02em;}
.sr-only{
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip:rect(0 0 0 0);
  white-space:nowrap;
  border:0;
}

/* ---------- 16. 响应式 ---------- */
@media (max-width:1100px){
  :root{--gutter:32px;}
  .grid--split,
  .grid--catalog{grid-template-columns:minmax(0,1fr);}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:40px 32px;}
}

@media (max-width:1024px){
  .nav-toggle{display:inline-flex;}
  .site-nav{
    position:absolute;
    top:100%;
    left:0;
    right:0;
    display:flex;
    flex-direction:column;
    align-items:stretch;
    gap:10px;
    margin-left:0;
    padding:18px var(--gutter) 26px;
    background:rgba(7,26,44,.985);
    border-bottom:1px solid var(--line);
    box-shadow:0 34px 60px -34px rgba(0,0,0,.98);
    opacity:0;
    visibility:hidden;
    transform:translateY(-10px);
    transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease),visibility var(--dur) var(--ease);
  }
  .site-nav[data-open]{opacity:1;visibility:visible;transform:none;}
  .nav-list{flex-direction:column;align-items:stretch;gap:2px;}
  .nav-link{
    justify-content:flex-start;
    padding:13px 14px;
    border-radius:14px;
    font-size:16px;
  }
  .nav-index{font-size:11px;}
  .nav-cta{width:100%;padding-block:14px;margin-top:6px;}
}

@media (max-width:720px){
  :root{--gutter:20px;--header-h:60px;}
  body{font-size:16px;}
  .brand-sub{display:none;}
  .section{padding-block:52px;}
  .section--tight{padding-block:32px;}
  .grid{gap:18px;}
  .card{padding:20px 20px;}
  .site-footer{padding-top:52px;margin-top:64px;}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:34px;}
  .footer-base{flex-direction:column;align-items:flex-start;gap:6px;}
  .to-top{right:16px;bottom:16px;width:42px;height:42px;}
  .filter-bar{border-radius:var(--radius-md);padding:10px;}
}

/* ---------- 17. 动效降级 ---------- */
@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;
  }
  .card:hover,
  .btn:hover,
  .tag:hover{transform:none;}
}