/* =========================================================
   优乐玩官方中文站 · 共享外壳样式 /assets/site.css
   设计语言：导航甲板 · 纸张叠层 · 印刷边框 · 清透渐变
   ========================================================= */

/* ---------- 1. 变量 ---------- */
:root{
  --navy:#0B2A4A;
  --navy-night:#061A2E;
  --cyan:#00D4C8;
  --coral:#FF6B4A;
  --paper:#F7F5F0;
  --ink:#101820;
  --mist:#D9DEE3;
  --pale-cyan:#E6FFFC;
  --teal-deep:#065E5A;
  --soft-coral:#FFE2DA;

  --font-head:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC","Noto Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-body:"Songti SC","Source Han Serif SC","Noto Serif SC","SimSun","STSong",Georgia,serif;
  --font-mono:ui-monospace,"SFMono-Regular",Menlo,Consolas,"Liberation Mono","Courier New",monospace;

  --radius-sm:6px;
  --radius:12px;
  --radius-lg:20px;
  --radius-xl:28px;
  --pill:999px;

  --shadow-paper:0 1px 0 rgba(16,24,32,.04),0 14px 30px -20px rgba(11,42,74,.35);
  --shadow-panel:0 26px 60px -34px rgba(6,26,46,.55);
  --shadow-cyan:0 14px 30px -18px rgba(0,212,200,.85);
  --shadow-coral:0 14px 30px -18px rgba(255,107,74,.8);

  --gutter:clamp(18px,4vw,44px);
  --maxw:1240px;
  --header-h:76px;
}

/* ---------- 2. Reset 与基础排版 ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background-color:var(--paper);
  background-image:
    radial-gradient(880px 420px at 92% -6%,rgba(0,212,200,.16),transparent 62%),
    radial-gradient(720px 400px at 2% 4%,rgba(255,107,74,.12),transparent 64%);
  background-repeat:no-repeat;
  color:var(--ink);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.85;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
body[data-nav-open]{overflow:hidden}
h1,h2,h3,h4,h5{font-family:var(--font-head);font-weight:800;line-height:1.25;letter-spacing:-.01em;margin:0 0 .6em}
h1{font-size:clamp(32px,4.6vw,56px)}
h2{font-size:clamp(26px,3.2vw,36px)}
h3{font-size:clamp(19px,2vw,24px)}
h4{font-size:17px}
p{margin:0 0 1.1em}
ul,ol{padding-left:1.2em}
li{margin:.25em 0}
a{color:var(--teal-deep);text-decoration-thickness:1px;text-underline-offset:3px}
a:hover{color:var(--coral)}
button{font:inherit;color:inherit}
img,svg,video{max-width:100%;height:auto;display:block}
hr{border:0;border-top:1px solid var(--mist);margin:2.4rem 0}
code,kbd,samp{font-family:var(--font-mono);font-size:.92em}
:focus-visible{outline:3px solid var(--cyan);outline-offset:3px;border-radius:4px}
.site-header :focus-visible,
.site-footer :focus-visible{outline:2px solid var(--coral);outline-offset:3px}
.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}

#main-content{display:block;scroll-margin-top:calc(var(--header-h) + 12px)}
[data-section]{scroll-margin-top:calc(var(--header-h) + 24px)}

/* ---------- 3. 跳至正文 ---------- */
.skip-link{
  position:absolute;left:16px;top:-70px;z-index:200;
  padding:11px 18px;
  background:var(--cyan);color:var(--navy-night);
  font-family:var(--font-head);font-weight:800;font-size:14px;
  text-decoration:none;
  border-radius:0 0 var(--radius) var(--radius);
  transition:top .22s ease;
}
.skip-link:focus{top:0;color:var(--navy-night)}

/* ---------- 4. 页头：导航甲板 ---------- */
.site-header{
  position:sticky;top:0;z-index:80;
  background-image:
    repeating-linear-gradient(90deg,rgba(0,212,200,.06) 0 1px,transparent 1px 72px),
    linear-gradient(180deg,#0B2A4A 0%,#061A2E 100%);
  color:var(--paper);
  border-bottom:1px solid rgba(0,212,200,.3);
  box-shadow:0 18px 36px -30px rgba(6,26,46,.95);
  transition:box-shadow .25s ease;
}
.site-header.is-scrolled{box-shadow:0 24px 44px -28px rgba(6,26,46,1)}
.header-inner{
  position:relative;z-index:2;
  max-width:var(--maxw);margin:0 auto;
  padding:13px var(--gutter);
  display:flex;align-items:center;justify-content:space-between;gap:18px;
}
.header-left{display:flex;align-items:center;gap:clamp(10px,1.6vw,20px);min-width:0}

/* 品牌 */
.brand{display:inline-flex;align-items:center;gap:11px;text-decoration:none;color:var(--paper);min-width:0}
.brand:hover{color:var(--paper)}
.brand-mark{
  flex:none;width:40px;height:40px;
  display:grid;place-items:center;
  border-radius:12px;
  background:linear-gradient(140deg,var(--cyan),#7CF3EA);
  color:var(--navy-night);
  font-family:var(--font-mono);font-size:15px;font-weight:700;letter-spacing:.04em;
  box-shadow:0 0 0 1px rgba(0,212,200,.55),0 12px 22px -14px rgba(0,212,200,.9);
}
.brand-text{display:flex;flex-direction:column;line-height:1.25;min-width:0}
.brand-name{font-family:var(--font-head);font-weight:800;font-size:17px;letter-spacing:.01em;white-space:nowrap}
.brand-tag{font-family:var(--font-mono);font-size:11px;letter-spacing:.18em;color:var(--cyan)}

/* 悬浮回访胶囊 */
.return-capsule{
  display:inline-flex;align-items:center;gap:8px;
  padding:8px 15px;
  border-radius:var(--pill);
  border:1px solid rgba(0,212,200,.45);
  background:rgba(0,212,200,.1);
  color:var(--paper);text-decoration:none;
  font-size:13px;line-height:1.2;white-space:nowrap;
  box-shadow:0 16px 30px -22px rgba(0,212,200,.95);
  transition:transform .2s ease,background .2s ease,border-color .2s ease;
}
.return-capsule:hover{transform:translateY(-3px);background:rgba(0,212,200,.2);border-color:rgba(0,212,200,.8);color:var(--paper)}
.capsule-dot{
  width:8px;height:8px;border-radius:50%;background:var(--cyan);flex:none;
  box-shadow:0 0 0 0 rgba(0,212,200,.6);
  animation:capsule-pulse 2.6s ease-out infinite;
}
@keyframes capsule-pulse{
  0%{box-shadow:0 0 0 0 rgba(0,212,200,.55)}
  70%{box-shadow:0 0 0 9px rgba(0,212,200,0)}
  100%{box-shadow:0 0 0 0 rgba(0,212,200,0)}
}
.capsule-label{color:rgba(247,245,240,.68);font-family:var(--font-mono);font-size:11px;letter-spacing:.12em}
.capsule-strong{font-family:var(--font-head);font-weight:700}

/* 移动导航按钮 */
.nav-toggle{
  display:none;align-items:center;gap:9px;
  padding:9px 15px;
  background:rgba(247,245,240,.06);
  border:1px solid rgba(217,222,227,.3);
  border-radius:var(--pill);
  color:var(--paper);cursor:pointer;
  font-family:var(--font-head);font-weight:700;font-size:13px;letter-spacing:.06em;
  transition:background .2s ease,border-color .2s ease;
}
.nav-toggle:hover{background:rgba(0,212,200,.16);border-color:rgba(0,212,200,.55)}
.nav-toggle-bars{display:grid;gap:4px;width:18px}
.nav-toggle-bar{display:block;height:2px;width:100%;background:var(--cyan);border-radius:2px;transition:transform .25s ease,opacity .2s ease}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

/* 栏目索引 */
.site-nav{display:flex;align-items:center}
.nav-list{display:flex;align-items:center;gap:4px;list-style:none;margin:0;padding:0}
.nav-item{margin:0}
.nav-link{
  display:inline-flex;align-items:baseline;gap:6px;
  padding:8px 13px;
  border:1px solid transparent;border-radius:var(--pill);
  color:rgba(247,245,240,.84);text-decoration:none;
  font-family:var(--font-head);font-weight:600;font-size:14px;line-height:1.4;
  transition:background .2s ease,color .2s ease,border-color .2s ease,font-size .2s ease,padding .2s ease;
}
.nav-link::before{
  content:attr(data-idx);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.04em;
  color:var(--cyan);opacity:.8;transform:translateY(-4px);
}
.nav-link:hover{color:#fff;background:rgba(247,245,240,.08);border-color:rgba(0,212,200,.35)}
.nav-link[aria-current="page"]{
  background:linear-gradient(135deg,var(--cyan),#57E9DF);
  color:var(--navy-night);border-color:transparent;
  box-shadow:var(--shadow-cyan);
}
.nav-link[aria-current="page"]::before{color:var(--navy-night);opacity:.75}
.site-header.is-scrolled .nav-link{padding:6px 11px;font-size:13px}
.site-header.is-scrolled .nav-link::before{opacity:.45}

/* 滚动进度线 */
.scroll-progress{
  position:absolute;left:0;right:0;bottom:-1px;height:3px;z-index:3;
  background:rgba(217,222,227,.14);overflow:hidden;
}
.scroll-progress-bar{
  display:block;height:100%;width:100%;
  transform:scaleX(0);transform-origin:0 50%;
  background:linear-gradient(90deg,var(--cyan),var(--coral));
  transition:transform .12s linear;
}

/* ---------- 5. 页脚：堆叠面板 ---------- */
.site-footer{
  position:relative;margin-top:clamp(48px,7vw,110px);
  padding:0 0 30px;
  background-image:
    repeating-linear-gradient(90deg,rgba(0,212,200,.05) 0 1px,transparent 1px 72px),
    linear-gradient(180deg,#0B2A4A 0%,#061A2E 62%,#03121F 100%);
  color:var(--paper);
  border-top:1px solid rgba(0,212,200,.3);
}
.footer-inner{max-width:var(--maxw);margin:0 auto;padding:0 var(--gutter)}
.footer-top{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 26px;
  padding:24px 0 26px;
  border-bottom:1px dashed rgba(217,222,227,.24);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.13em;
  color:rgba(247,245,240,.62);
}
.footer-top-strong{color:var(--cyan)}
.stamp{
  display:inline-flex;align-items:center;gap:8px;
  padding:6px 13px;border-radius:var(--radius-sm);
  border:1px dashed rgba(0,212,200,.6);
  color:var(--cyan);font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;
  transform:rotate(-1.6deg);
}
.footer-stack{
  display:grid;
  grid-template-columns:1.5fr 1fr 1fr 1.25fr;
  gap:clamp(14px,2vw,26px);
  padding:36px 0 6px;
  align-items:start;
}
.footer-panel{
  background:rgba(247,245,240,.05);
  border:1px solid rgba(217,222,227,.16);
  border-radius:var(--radius-lg);
  padding:22px 20px 24px;
  box-shadow:var(--shadow-panel);
}
.footer-panel:nth-child(2){transform:translateY(16px)}
.footer-panel:nth-child(3){transform:translateY(32px)}
.footer-panel:nth-child(4){transform:translateY(8px)}
.footer-panel--brand{background:rgba(0,212,200,.08);border-color:rgba(0,212,200,.28)}
.footer-panel-title{
  display:flex;align-items:center;gap:12px;
  margin:0 0 16px;
  font-family:var(--font-head);font-size:14px;font-weight:800;letter-spacing:.08em;
  color:var(--cyan);
}
.footer-panel-title::after{content:"";flex:1;height:1px;background:rgba(217,222,227,.2)}
.footer-brand-name{
  margin:0 0 8px;font-family:var(--font-head);font-weight:800;font-size:20px;color:var(--paper);
}
.footer-brand-line{margin:0;font-size:14px;line-height:1.85;color:rgba(247,245,240,.72)}
.footer-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.footer-list{list-style:none;margin:0;padding:0;display:grid;gap:9px}
.footer-list li{margin:0}
.footer-link{
  display:inline-flex;align-items:center;gap:8px;
  color:rgba(247,245,240,.82);text-decoration:none;font-size:14px;
  border-bottom:1px solid transparent;
  transition:color .18s ease,transform .18s ease,border-color .18s ease;
}
.footer-link::before{content:"›";font-family:var(--font-mono);color:var(--coral)}
.footer-link:hover{color:var(--cyan);border-bottom-color:rgba(0,212,200,.5);transform:translateX(3px)}
.footer-contact{display:grid;gap:14px}
.footer-contact-row{display:grid;gap:4px}
.footer-contact-label{font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;color:rgba(247,245,240,.5)}
.footer-contact-value{font-size:14px;line-height:1.7;color:rgba(247,245,240,.9);word-break:break-word}
.copy-btn{
  justify-self:start;
  padding:4px 11px;
  background:transparent;
  border:1px dashed rgba(0,212,200,.55);
  border-radius:var(--pill);
  color:var(--cyan);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  cursor:pointer;
  transition:background .18s ease,color .18s ease,border-color .18s ease;
}
.copy-btn:hover{background:rgba(0,212,200,.16)}
.copy-btn.is-copied{background:var(--cyan);border-color:var(--cyan);color:var(--navy-night)}
.footer-contact-note{margin:2px 0 0;font-size:12.5px;line-height:1.75;color:rgba(247,245,240,.56)}
.footer-bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 24px;
  margin-top:42px;padding-top:22px;
  border-top:1px solid rgba(217,222,227,.16);
}
.footer-meta{
  margin:0;font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:rgba(247,245,240,.6);
}

/* ---------- 6. 通用布局 ---------- */
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 var(--gutter)}
.content-narrow{max-width:820px}
.section{padding:clamp(46px,7vw,96px) 0}
.section--tight{padding:clamp(28px,4vw,52px) 0}
.grid{display:grid;gap:clamp(16px,2.4vw,28px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}

/* ---------- 7. 面板与堆叠 ---------- */
.panel{
  position:relative;
  padding:clamp(20px,3vw,36px);
  background:#fff;
  border:1px solid var(--mist);
  border-radius:var(--radius-lg);
  box-shadow:var(--shadow-paper);
}
.panel--paper{background:var(--paper)}
.panel--deep{
  background-image:linear-gradient(150deg,var(--navy),var(--navy-night));
  border-color:rgba(0,212,200,.3);
  color:var(--paper);
}
.panel--deep h1,.panel--deep h2,.panel--deep h3{color:var(--paper)}
.panel--deep a{color:var(--cyan)}
.stacked{position:relative;isolation:isolate}
.stacked::before{
  content:"";position:absolute;inset:0;z-index:-1;
  transform:translate(10px,10px);
  border-radius:inherit;
  background:var(--pale-cyan);
  border:1px solid var(--mist);
}

/* ---------- 8. 标题与索引元素 ---------- */
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.24em;text-transform:uppercase;
  color:var(--teal-deep);
}
.panel--deep .eyebrow{color:var(--cyan)}
.section-title{margin:.4em 0 .5em;font-family:var(--font-head);font-size:clamp(26px,3.4vw,40px);font-weight:800}
.lead{font-size:clamp(16px,1.5vw,19px);line-height:1.95;color:#2C3A47;max-width:64ch}
.panel--deep .lead{color:rgba(247,245,240,.85)}
.big-index{
  display:block;
  font-family:var(--font-mono);font-weight:700;
  font-size:clamp(44px,7vw,90px);line-height:.9;letter-spacing:-.05em;
  color:rgba(11,42,74,.16);
  -webkit-text-stroke:1.5px rgba(11,42,74,.3);
}
.panel--deep .big-index{color:rgba(230,255,252,.08);-webkit-text-stroke-color:rgba(0,212,200,.5)}

/* ---------- 9. 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  padding:13px 24px;
  border:1px solid transparent;border-radius:var(--pill);
  font-family:var(--font-head);font-weight:700;font-size:15px;line-height:1.4;
  text-decoration:none;cursor:pointer;
  transition:transform .18s ease,box-shadow .18s ease,background .18s ease,color .18s ease,border-color .18s ease;
}
.btn:hover{transform:translateY(-2px)}
.btn--primary{background:linear-gradient(135deg,var(--cyan),#59E9DF);color:var(--navy-night);box-shadow:var(--shadow-cyan)}
.btn--primary:hover{color:var(--navy-night)}
.btn--coral{background:linear-gradient(135deg,var(--coral),#FF8F72);color:#3A1006;box-shadow:var(--shadow-coral)}
.btn--coral:hover{color:#3A1006}
.btn--ghost{background:transparent;border-color:var(--navy);color:var(--navy)}
.btn--ghost:hover{background:var(--navy);color:var(--paper)}
.btn--ghost-light{background:transparent;border-color:rgba(217,222,227,.45);color:var(--paper)}
.btn--ghost-light:hover{background:rgba(247,245,240,.12);color:var(--paper);border-color:var(--cyan)}

/* ---------- 10. 面包屑 ---------- */
.breadcrumb{padding:20px 0 0;font-family:var(--font-mono);font-size:12px;letter-spacing:.08em}
.breadcrumb-list{list-style:none;display:flex;flex-wrap:wrap;gap:6px;margin:0;padding:0}
.breadcrumb-item{display:inline-flex;align-items:center;gap:6px;color:var(--teal-deep)}
.breadcrumb-item:not(:last-child)::after{content:"/";color:var(--mist);margin-left:2px}
.breadcrumb-item[aria-current="page"]{color:#54606B}
.breadcrumb-link{color:inherit;text-decoration:none;border-bottom:1px solid rgba(6,94,90,.35)}
.breadcrumb-link:hover{color:var(--coral);border-bottom-color:rgba(255,107,74,.6)}

/* ---------- 11. 粘性侧边索引 ---------- */
.sticky-index{position:sticky;top:calc(var(--header-h) + 20px);align-self:start}
.index-list{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.index-link{
  display:flex;align-items:baseline;gap:10px;
  padding:8px 12px;
  border-left:2px solid var(--mist);
  color:#54606B;text-decoration:none;font-size:14px;
  transition:color .2s ease,border-color .2s ease,background .2s ease;
}
.index-link:hover{color:var(--navy);border-left-color:var(--cyan);background:var(--pale-cyan)}
.index-link[aria-current="true"]{color:var(--navy);border-left-color:var(--coral);background:var(--soft-coral);font-weight:700}

/* ---------- 12. 标签、筛选 ---------- */
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 11px;border-radius:var(--pill);
  border:1px solid rgba(217,222,227,.32);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;
  color:rgba(247,245,240,.82);
}
.tag--cyan{border-color:rgba(0,212,200,.55);background:rgba(0,212,200,.12);color:var(--cyan)}
.tag--coral{border-color:rgba(255,107,74,.55);background:rgba(255,107,74,.14);color:#FFB4A0}
.tag--light{border-color:var(--teal-deep);background:var(--pale-cyan);color:var(--teal-deep)}
.chip-bar{display:flex;flex-wrap:wrap;gap:8px}
.chip{
  padding:8px 16px;
  background:#fff;border:1px solid var(--mist);border-radius:var(--pill);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;
  color:#54606B;cursor:pointer;
  transition:background .18s ease,color .18s ease,border-color .18s ease,transform .18s ease;
}
.chip:hover{border-color:var(--teal-deep);color:var(--teal-deep);transform:translateY(-1px)}
.chip[aria-pressed="true"]{background:var(--navy);border-color:var(--navy);color:var(--paper)}

/* ---------- 13. 表格 ---------- */
.data-table{width:100%;border-collapse:collapse;font-size:15px;background:#fff;border-radius:var(--radius);overflow:hidden}
.data-table caption{caption-side:top;text-align:left;font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:#54606B;padding:0 0 10px}
.data-table th{
  font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;
  color:var(--teal-deep);text-align:left;padding:13px 16px;border-bottom:2px solid var(--navy);white-space:nowrap;
}
.data-table td{padding:15px 16px;border-bottom:1px solid var(--mist);vertical-align:top}
.data-table tbody tr:hover{background:var(--pale-cyan)}
.data-table tr[data-selected]{background:var(--soft-coral)}

/* ---------- 14. 图像容器 ---------- */
.media-frame{
  position:relative;isolation:isolate;overflow:hidden;
  aspect-ratio:16 / 10;
  border-radius:var(--radius);
  border:1px solid rgba(11,42,74,.22);
  background-image:linear-gradient(140deg,var(--navy),var(--navy-night));
}
.media-frame img{width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;opacity:.45;mix-blend-mode:screen;
  background-image:
    linear-gradient(rgba(0,212,200,.14) 1px,transparent 1px),
    linear-gradient(90deg,rgba(0,212,200,.14) 1px,transparent 1px);
  background-size:36px 36px;
}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:3 / 4}
.media-frame--square{aspect-ratio:1 / 1}
.media-frame[data-label]::before{
  content:attr(data-label);
  position:absolute;inset:0;z-index:1;
  display:grid;place-items:center;padding:18px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.2em;line-height:1.9;
  text-align:center;color:rgba(230,255,252,.78);
}
.media-caption{margin:10px 0 0;font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:#54606B}

/* ---------- 15. 可展开内容组 ---------- */
.accordion{
  border:1px solid var(--mist);border-radius:var(--radius);
  background:#fff;overflow:hidden;
}
.accordion + .accordion{margin-top:12px}
.accordion-trigger{
  width:100%;display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:18px 20px;background:transparent;border:0;text-align:left;cursor:pointer;
  font-family:var(--font-head);font-weight:700;font-size:16px;color:var(--ink);
  transition:background .2s ease,color .2s ease;
}
.accordion-trigger:hover{background:var(--pale-cyan)}
.accordion-trigger[aria-expanded="true"]{background:var(--pale-cyan);color:var(--teal-deep)}
.accordion-icon{
  flex:none;width:22px;height:22px;display:grid;place-items:center;
  border-radius:50%;border:1px solid var(--mist);
  font-family:var(--font-mono);font-size:13px;color:var(--teal-deep);
  transition:transform .25s ease,background .2s ease,color .2s ease;
}
.accordion-trigger[aria-expanded="true"] .accordion-icon{transform:rotate(45deg);background:var(--cyan);color:var(--navy-night);border-color:var(--cyan)}
.accordion-panel{display:grid;grid-template-rows:0fr;transition:grid-template-rows .32s ease;background:#fff}
.accordion-panel[data-open]{grid-template-rows:1fr}
.accordion-body{overflow:hidden;min-height:0;padding:0 20px;font-size:16px;color:#2C3A47}
.accordion-panel[data-open] > .accordion-body{padding:0 20px 20px}

/* ---------- 16. 进入显现 ---------- */
.reveal{opacity:0;transform:translateY(18px);transition:opacity .6s ease,transform .6s cubic-bezier(.2,.7,.3,1)}
.reveal.is-visible{opacity:1;transform:none}

/* ---------- 17. 响应式 ---------- */
@media (max-width:1180px){
  .capsule-label{display:none}
}
@media (max-width:1080px){
  .grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-stack{grid-template-columns:1.4fr 1fr 1fr}
  .footer-panel:nth-child(4){grid-column:1 / -1;transform:none}
}
@media (max-width:980px){
  :root{--header-h:66px}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:absolute;top:100%;left:0;right:0;
    display:grid;grid-template-rows:0fr;
    background-image:linear-gradient(180deg,rgba(6,26,46,.99),rgba(11,42,74,.99));
    border-bottom:1px solid rgba(0,212,200,.32);
    box-shadow:0 30px 50px -30px rgba(6,26,46,1);
    overflow:hidden;visibility:hidden;
    transition:grid-template-rows .34s ease,visibility .34s ease;
  }
  .site-nav[data-open]{grid-template-rows:1fr;visibility:visible}
  .nav-list{
    flex-direction:column;align-items:stretch;gap:2px;
    padding:12px var(--gutter) 20px;min-height:0;overflow:hidden;
  }
  .nav-link{
    width:100%;justify-content:flex-start;gap:10px;
    padding:13px 14px;border-radius:10px;font-size:16px;
    border-color:rgba(217,222,227,.14);
  }
  .nav-link::before{transform:none;font-size:11px}
  .site-header.is-scrolled .nav-link{padding:13px 14px;font-size:16px}
  .footer-stack{grid-template-columns:repeat(2,minmax(0,1fr));padding-top:30px}
  .footer-panel:nth-child(2),
  .footer-panel:nth-child(3),
  .footer-panel:nth-child(4){transform:none}
  .sticky-index{position:static;top:auto}
}
@media (max-width:820px){
  .brand-tag{display:none}
  .grid--2,.grid--3,.grid--4{grid-template-columns:minmax(0,1fr)}
  .footer-top{justify-content:flex-start}
}
@media (max-width:640px){
  body{font-size:16px}
  .return-capsule{display:none}
  .brand-name{font-size:15px}
  .brand-mark{width:34px;height:34px;border-radius:10px;font-size:13px}
  .footer-stack{grid-template-columns:minmax(0,1fr)}
  .footer-bottom{flex-direction:column;align-items:flex-start}
}

/* ---------- 18. 动效与无障碍偏好 ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important}
  .reveal{opacity:1;transform:none}
  .scroll-progress-bar{transition:none}
}