/* ============================================================
   新2登录旧网 · 中国站  共享样式  /assets/site.css
   色彩：湘江夜蓝基底 + 暖橙金入口 + 青瓷绿帮助中心
   ============================================================ */

/* ---------- 1 重置 ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dt,dd{margin:0}
ul,ol{list-style:none;padding:0}
img,svg,video,canvas{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0;cursor:pointer}
i,em{font-style:normal}
[hidden]{display:none!important}

/* ---------- 2 变量 ---------- */
:root{
  --ink-900:#0B1826;
  --ink-700:#14293E;
  --ink-600:#2B3742;
  --paper:#F5F1E8;
  --amber:#E4913A;
  --amber-soft:#F3B96B;
  --celadon:#5C8F7B;
  --celadon-soft:#A9C9B9;
  --moss:#6E7A4E;
  --clay:#B4604A;
  --cloud:#C6CDD4;
  --white:#FFFFFF;

  --font-display:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:system-ui,-apple-system,"Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --line-soft:rgba(198,205,212,.14);
  --line-mid:rgba(198,205,212,.28);
  --line-celadon:rgba(169,201,185,.30);
  --line-amber:rgba(228,145,58,.55);
  --glass-bg:rgba(20,41,62,.72);

  --dock-w:19rem;
  --shell-max:1280px;
  --gutter:clamp(1.25rem,4vw,2.5rem);
  --radius:0.9rem;
  --ease:cubic-bezier(.22,.61,.36,1);
}

/* ---------- 3 基础排版 ---------- */
body{
  background:var(--ink-900);
  color:var(--cloud);
  font-family:var(--font-body);
  font-size:1.05rem;
  line-height:1.85;
  letter-spacing:.01em;
  min-height:100vh;
}
h1,h2,h3,h4{color:var(--white);font-family:var(--font-display);font-weight:700;line-height:1.25;letter-spacing:-.01em}
h1{font-size:clamp(2rem,4.6vw,3.2rem)}
h2{font-size:clamp(1.6rem,3vw,2.6rem)}
h3{font-size:clamp(1.15rem,1.6vw,1.45rem)}
p{max-width:38ch}
strong{color:var(--paper);font-weight:700}
::selection{background:var(--amber);color:var(--ink-900)}

:focus-visible{outline:2px solid var(--amber-soft);outline-offset:3px;border-radius:3px}

.display{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(3.2rem,8vw,7rem);
  line-height:1.02;
  letter-spacing:-.02em;
  color:var(--white);
}

/* ---------- 4 跳转链接 ---------- */
.skip-link{
  position:absolute;left:1rem;top:-5rem;z-index:200;
  padding:.7rem 1.15rem;border-radius:0 0 .55rem .55rem;
  background:var(--amber);color:var(--ink-900);
  font-weight:700;font-size:.9rem;letter-spacing:.08em;
  transition:top .18s var(--ease);
}
.skip-link:focus{top:0}

/* ---------- 5 页头 ---------- */
.site-header{
  position:sticky;top:0;z-index:60;
  background:rgba(11,24,38,.94);
  -webkit-backdrop-filter:blur(16px) saturate(150%);
  backdrop-filter:blur(16px) saturate(150%);
  border-bottom:1px solid var(--line-soft);
}
.header-inner{
  width:100%;max-width:var(--shell-max);margin-inline:auto;
  padding-inline:var(--gutter);
}

/* 上层：品牌说明 + 快速入口 */
.header-top{
  overflow:hidden;
  max-height:6rem;
  border-bottom:1px solid rgba(198,205,212,.10);
  transition:max-height .26s var(--ease),opacity .2s var(--ease),border-color .2s var(--ease);
}
.site-header[data-scrolled="true"] .header-top{max-height:0;opacity:0;border-color:transparent}
.header-top__inner{display:flex;align-items:center;gap:1.25rem;padding-block:.8rem}

.brand{display:flex;align-items:center;gap:.7rem;flex:0 0 auto}
.brand-mark{
  display:grid;place-items:center;width:2.4rem;height:2.4rem;
  border-radius:.55rem;background:var(--amber);color:var(--ink-900);
  font-family:var(--font-display);font-weight:900;font-size:1.3rem;line-height:1;
}
.brand-text{display:flex;flex-direction:column;line-height:1.3}
.brand-name{color:var(--white);font-weight:700;font-size:1.05rem;letter-spacing:.04em}
.brand-sub{color:var(--celadon-soft);font-size:.7rem;letter-spacing:.22em}
.brand-tag{
  max-width:none;padding-left:1.1rem;border-left:1px solid var(--line-mid);
  color:var(--cloud);font-size:.8rem;letter-spacing:.18em;
}

.quick-actions{display:flex;align-items:center;gap:.6rem;margin-left:auto;flex:0 0 auto}
.quick-link{
  display:inline-flex;align-items:center;
  padding:.42rem .95rem;border-radius:999px;
  border:1px solid var(--line-amber);color:var(--amber-soft);
  font-size:.86rem;letter-spacing:.08em;white-space:nowrap;
  transition:background .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease);
}
.quick-link:hover,.quick-link:focus-visible{background:rgba(228,145,58,.16);border-color:var(--amber-soft);color:var(--white)}
.quick-link--primary{background:var(--amber);border-color:var(--amber);color:var(--ink-900);font-weight:700}
.quick-link--primary:hover,.quick-link--primary:focus-visible{background:var(--amber-soft);border-color:var(--amber-soft);color:var(--ink-900)}

/* 下层：栏目条 */
.header-main{background:linear-gradient(90deg,rgba(92,143,123,.16),rgba(11,24,38,0) 62%)}
.header-main__inner{display:flex;align-items:center;gap:.9rem;padding-block:.35rem}
.nav-brand{display:none}
.nav-caption{
  flex:0 0 auto;display:none;
  writing-mode:vertical-rl;text-orientation:upright;
  font-size:.68rem;letter-spacing:.32em;color:var(--moss);
}
.site-nav{flex:1 1 auto;min-width:0}
.nav-list{display:flex;flex:1 1 auto;flex-wrap:wrap}
.nav-item{flex:1 1 0;min-width:0}
.nav-link{
  position:relative;display:flex;align-items:baseline;gap:.5rem;
  padding:.85rem .75rem;color:var(--cloud);
  font-size:.98rem;letter-spacing:.08em;
  transition:color .18s var(--ease),background .18s var(--ease);
}
.nav-link::after{
  content:"";position:absolute;left:.75rem;right:.75rem;bottom:.3rem;height:2px;
  background:var(--amber);transform:scaleX(0);transform-origin:left;
  transition:transform .18s var(--ease);
}
.nav-link:hover,.nav-link:focus-visible{color:var(--white);background:rgba(228,145,58,.08)}
.nav-link:hover::after,.nav-link:focus-visible::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--white)}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}
.nav-link[aria-current="page"] .nav-index{color:var(--amber)}
.nav-index{
  font-family:var(--font-mono);font-size:.66rem;letter-spacing:.1em;
  color:var(--moss);font-variant-numeric:tabular-nums;
}

.nav-toggle{
  display:none;align-items:center;gap:.55rem;margin-left:auto;
  padding:.5rem .8rem;border:1px solid var(--line-mid);border-radius:.5rem;
  color:var(--paper);font-size:.82rem;letter-spacing:.12em;
  transition:border-color .2s var(--ease),color .2s var(--ease),background .2s var(--ease);
}
.nav-toggle[aria-expanded="true"]{border-color:var(--amber);color:var(--amber-soft);background:rgba(228,145,58,.12)}
.nav-toggle__bars{display:grid;gap:3px;width:14px}
.nav-toggle__bars i{display:block;height:1.5px;background:currentColor;border-radius:1px}
.nav-toggle__bars i:nth-child(2){width:10px}

/* ---------- 6 帮助中心停靠栏（桌面固定右栏 / 移动底部抽屉） ---------- */
.help-handle{
  position:fixed;right:1rem;bottom:1rem;z-index:90;
  display:inline-flex;align-items:center;
  padding:.6rem 1.05rem;border-radius:999px;
  background:var(--celadon);color:#08130F;
  font-weight:700;font-size:.85rem;letter-spacing:.12em;
  box-shadow:0 12px 32px -14px rgba(0,0,0,.9);
  transition:background .18s var(--ease),color .18s var(--ease);
}
.help-handle:hover,.help-handle:focus-visible{background:var(--celadon-soft)}
.help-handle[aria-expanded="true"]{background:var(--amber);color:var(--ink-900)}

.help-dock{
  position:fixed;left:0;right:0;bottom:0;z-index:89;
  max-height:78vh;overflow:auto;
  padding:1.35rem 1.35rem 5rem;
  background:var(--ink-700);
  border-top:2px solid var(--celadon);
  border-radius:1.1rem 1.1rem 0 0;
  box-shadow:0 -18px 50px -24px rgba(0,0,0,.95);
  transform:translateY(105%);visibility:hidden;
  transition:transform .22s var(--ease),visibility .22s var(--ease);
}
.help-dock[data-open]{transform:none;visibility:visible}
.help-dock__eyebrow{
  max-width:none;font-size:.68rem;letter-spacing:.32em;color:var(--celadon-soft);
}
.help-dock__title{font-size:1.05rem;margin:.4rem 0 1.1rem;line-height:1.5;color:var(--white)}
.help-groups{display:grid;gap:.15rem}
.help-group{border-top:1px solid var(--line-soft)}
.help-group:last-child{border-bottom:1px solid var(--line-soft)}
.help-group__btn{
  width:100%;display:flex;align-items:center;justify-content:space-between;gap:.6rem;
  padding:.75rem .1rem;text-align:left;
  color:var(--paper);font-size:.92rem;letter-spacing:.06em;
  transition:color .18s var(--ease);
}
.help-group__btn:hover,.help-group__btn:focus-visible{color:var(--celadon-soft)}
.help-group__dot{
  flex:0 0 auto;width:.45rem;height:.45rem;border-radius:50%;
  background:var(--celadon);
  transition:background .18s var(--ease),transform .18s var(--ease);
}
.help-group__btn[aria-expanded="true"] .help-group__dot{background:var(--amber);transform:scale(1.4)}
.help-group__panel{
  max-height:0;opacity:0;visibility:hidden;overflow:hidden;
  transition:max-height .22s var(--ease),opacity .18s var(--ease),visibility .22s var(--ease);
}
.help-group__panel[data-open]{max-height:22rem;opacity:1;visibility:visible}
.help-link{
  display:block;margin:0 0 .3rem;padding:.5rem .1rem .5rem .85rem;
  border-left:2px solid var(--line-celadon);
  color:var(--cloud);font-size:.86rem;letter-spacing:.04em;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.help-link:hover,.help-link:focus-visible{color:var(--white);border-left-color:var(--amber)}
.help-link[aria-current="page"]{color:var(--amber-soft);border-left-color:var(--amber)}
.help-dock__foot{
  max-width:none;margin-top:1.1rem;padding-top:1rem;border-top:1px solid var(--line-soft);
}
.help-dock__cta{
  display:inline-flex;align-items:center;gap:.4rem;
  padding-bottom:.15rem;border-bottom:1px solid currentColor;
  color:var(--celadon-soft);font-size:.88rem;letter-spacing:.1em;
  transition:color .18s var(--ease);
}
.help-dock__cta:hover,.help-dock__cta:focus-visible{color:var(--amber-soft)}

/* ---------- 7 页脚 ---------- */
.site-footer{
  position:relative;
  background:linear-gradient(180deg,var(--ink-900),#080F19);
  border-top:1px solid var(--line-soft);
  color:var(--cloud);
}
.footer-inner{
  width:100%;max-width:var(--shell-max);margin-inline:auto;
  padding:clamp(2.5rem,5vw,4rem) var(--gutter) 2rem;
}
.footer-top{display:grid;grid-template-columns:minmax(0,1fr);gap:2.5rem}
.footer-brand__mark{
  max-width:none;font-family:var(--font-display);font-weight:900;
  font-size:3.4rem;line-height:1;color:rgba(228,145,58,.85);letter-spacing:-.04em;
}
.footer-brand__name{max-width:none;color:var(--white);font-weight:700;font-size:1.35rem;letter-spacing:.06em;margin-top:.4rem}
.footer-brand__sub{max-width:none;color:var(--celadon-soft);font-size:.76rem;letter-spacing:.26em;margin-top:.35rem}
.footer-brand__note{
  max-width:none;margin-top:1rem;
  writing-mode:vertical-rl;text-orientation:upright;
  font-size:.72rem;letter-spacing:.32em;color:var(--moss);
}
.footer-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1.75rem}
.footer-col__title{
  position:relative;padding-bottom:.65rem;margin-bottom:.9rem;
  border-bottom:1px solid var(--line-soft);
  color:var(--paper);font-size:.76rem;letter-spacing:.28em;font-weight:700;
}
.footer-col__title::before{
  content:"";display:inline-block;width:.4rem;height:.4rem;margin-right:.5rem;
  background:var(--moss);vertical-align:middle;
}
.footer-list li + li{margin-top:.55rem}
.footer-list a{
  position:relative;color:var(--cloud);font-size:.92rem;letter-spacing:.06em;
  transition:color .18s var(--ease);
}
.footer-list a::after{
  content:"";position:absolute;left:0;right:0;bottom:-2px;height:1px;
  background:var(--amber-soft);transform:scaleX(0);transform-origin:left;
  transition:transform .18s var(--ease);
}
.footer-list a:hover,.footer-list a:focus-visible{color:var(--white)}
.footer-list a:hover::after,.footer-list a:focus-visible::after{transform:scaleX(1)}
.footer-list a[aria-current="page"]{color:var(--amber-soft)}
.footer-list a[aria-current="page"]::after{transform:scaleX(1)}

.footer-contact{
  display:grid;gap:.85rem;margin-top:2.5rem;padding-top:1.75rem;
  border-top:1px solid var(--line-soft);
}
.footer-contact__row{display:flex;gap:.85rem;align-items:baseline;max-width:none;font-size:.92rem}
.footer-contact__key{flex:0 0 5.5rem;color:var(--celadon-soft);font-size:.76rem;letter-spacing:.16em}
.footer-contact__val{color:var(--paper);word-break:break-word}
.footer-note{
  max-width:none;margin-top:1.1rem;color:var(--moss);font-size:.84rem;letter-spacing:.06em;
}
.footer-legal{
  display:flex;flex-wrap:wrap;gap:.75rem 1.5rem;align-items:center;justify-content:space-between;
  margin-top:2rem;padding-top:1.25rem;border-top:1px solid var(--line-soft);
  font-size:.82rem;
}
.footer-legal__nav{display:flex;flex-wrap:wrap;gap:.6rem 1.25rem}
.footer-legal__nav a{color:var(--celadon-soft);transition:color .18s var(--ease)}
.footer-legal__nav a:hover,.footer-legal__nav a:focus-visible{color:var(--amber-soft)}
.footer-meta{max-width:none;color:var(--cloud);letter-spacing:.06em}

/* 回到顶部 */
.to-top{
  position:fixed;right:1.25rem;bottom:4.7rem;z-index:88;
  display:grid;place-items:center;width:3.1rem;height:3.1rem;
  border-radius:50%;border:1px solid var(--line-mid);
  background:rgba(20,41,62,.92);color:var(--paper);
  font-size:.68rem;letter-spacing:.06em;
  opacity:0;visibility:hidden;
  transition:opacity .2s var(--ease),visibility .2s var(--ease),border-color .2s var(--ease),color .2s var(--ease);
}
.to-top[data-visible]{opacity:1;visibility:visible}
.to-top:hover,.to-top:focus-visible{border-color:var(--amber);color:var(--amber-soft)}

/* ---------- 8 主内容与栅格 ---------- */
#main-content{
  width:100%;max-width:var(--shell-max);margin-inline:auto;
  padding:clamp(1.75rem,4vw,3.25rem) var(--gutter) 5rem;
  display:block;
}
.container{width:100%;max-width:var(--shell-max);margin-inline:auto;padding-inline:var(--gutter)}
.grid{display:grid;gap:1.25rem}
.grid--2,.grid--3,.grid--steps,.grid--split{grid-template-columns:minmax(0,1fr)}
.grid--split{align-items:start;gap:2rem}
.prose{max-width:720px}
.prose p + p{margin-top:1.05rem}
.prose p{max-width:38ch}
.lede{max-width:36ch;font-size:1.05rem;color:var(--cloud)}
.note{max-width:none;font-size:.8rem;letter-spacing:.14em;color:var(--moss)}

/* ---------- 9 章节与色带 ---------- */
.band{padding-block:clamp(2.5rem,6vw,5rem)}
.band--deep{background:var(--ink-900)}
.band--mid{background:var(--ink-700)}
.band--paper{background:var(--paper);color:var(--ink-600)}
.band--paper h1,.band--paper h2,.band--paper h3{color:var(--ink-900)}
.band--paper .lede,.band--paper .prose{color:var(--ink-600)}
.band--paper .section__label{color:var(--moss)}
.band--moss{background:linear-gradient(180deg,rgba(110,122,78,.22),rgba(11,24,38,0) 70%)}
.section{display:block}
.section__head{margin-bottom:clamp(1.5rem,3vw,2.5rem)}
.section__label{
  display:block;max-width:none;margin-bottom:.6rem;
  font-size:.72rem;letter-spacing:.35em;color:var(--celadon-soft);
}
.section__title{font-size:clamp(1.6rem,3vw,2.6rem)}

/* ---------- 10 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:.5rem;
  padding:.75rem 1.4rem;border-radius:.6rem;border:1px solid transparent;
  font-size:.95rem;font-weight:700;letter-spacing:.08em;
  transition:background .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease);
}
.btn--entry{background:var(--amber);color:var(--ink-900)}
.btn--entry:hover,.btn--entry:focus-visible{background:var(--amber-soft)}
.btn--help{background:var(--celadon);color:#08130F}
.btn--help:hover,.btn--help:focus-visible{background:var(--celadon-soft)}
.btn--ghost{border-color:var(--line-mid);color:var(--paper)}
.btn--ghost:hover,.btn--ghost:focus-visible{border-color:var(--amber);color:var(--amber-soft)}

/* ---------- 11 卡片 / 玻璃层 ---------- */
.card{
  background:var(--ink-700);border:1px solid var(--line-soft);border-radius:var(--radius);
  padding:1.5rem;
  transition:border-color .2s var(--ease);
}
.card:hover,.card:focus-within{border-color:var(--amber)}
.card--help:hover,.card--help:focus-within{border-color:var(--celadon)}
.card__title{color:var(--white);font-size:1.15rem;margin-bottom:.5rem}
.card__meta{max-width:none;font-size:.76rem;letter-spacing:.22em;color:var(--moss)}
.glass{
  background:var(--glass-bg);
  -webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);
  border:1px solid var(--line-celadon);border-radius:var(--radius);
}

/* ---------- 12 步骤与数据 ---------- */
.step{position:relative;padding-top:.5rem}
.step__num{
  display:block;font-family:var(--font-display);font-weight:900;
  font-size:clamp(2.6rem,6vw,3.4rem);line-height:1;
  color:var(--amber);font-variant-numeric:tabular-nums;
  margin-bottom:.6rem;
}
.step__title{color:var(--white);font-size:1.15rem;margin-bottom:.4rem}
.step__text{max-width:34ch;font-size:.95rem}
.stat{display:grid;gap:.2rem}
.stat__num{
  font-family:var(--font-display);font-weight:900;line-height:1;
  font-size:clamp(1.9rem,4vw,2.6rem);color:var(--white);
  font-variant-numeric:tabular-nums;
}
.stat__label{max-width:none;font-size:.76rem;letter-spacing:.2em;color:var(--moss)}

/* ---------- 13 图片容器（供页面阶段放置图片） ---------- */
.media-frame{
  position:relative;width:100%;aspect-ratio:16/9;
  background:linear-gradient(120deg,var(--ink-700),var(--ink-600));
  border:1px solid var(--line-soft);border-radius:var(--radius);
  overflow:hidden;
}
.media-frame::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:repeating-linear-gradient(115deg,rgba(169,201,185,.08) 0 2px,transparent 2px 14px);
}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--thumb{aspect-ratio:4/3}
.media-frame__img{position:relative;width:100%;height:100%;object-fit:cover}
.media-frame__cap{
  position:absolute;left:0;right:0;bottom:0;
  padding:1.1rem 1.25rem .9rem;
  background:linear-gradient(180deg,rgba(11,24,38,0),rgba(11,24,38,.88));
  color:var(--paper);font-size:.82rem;letter-spacing:.08em;max-width:none;
}

/* ---------- 14 面包屑 / 标签 ---------- */
.crumbs{margin-bottom:1.25rem;font-size:.8rem;letter-spacing:.1em}
.crumbs__list{display:flex;flex-wrap:wrap;align-items:center;gap:.35rem .4rem}
.crumbs__item + .crumbs__item::before{content:"/";margin-right:.5rem;color:var(--moss)}
.crumbs__item{display:flex;align-items:center}
.crumbs__link{color:var(--cloud);transition:color .18s var(--ease)}
.crumbs__link:hover,.crumbs__link:focus-visible{color:var(--amber-soft)}
.crumbs__item[aria-current="page"]{color:var(--paper)}
.tag{
  display:inline-flex;align-items:center;gap:.4rem;
  padding:.25rem .7rem;border-radius:999px;
  border:1px solid var(--line-celadon);color:var(--celadon-soft);
  font-size:.74rem;letter-spacing:.14em;white-space:nowrap;
}
.tag--moss{border-color:rgba(110,122,78,.55);color:#B9C39A}
.tag--clay{border-color:rgba(180,96,74,.6);color:#E3A392}

/* ---------- 15 响应式 ---------- */
@media (min-width:640px){
  .footer-grid{grid-template-columns:repeat(4,minmax(0,1fr))}
  .footer-contact{grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem 2rem}
  .grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (min-width:760px){
  .grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
  .grid--steps{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media (min-width:900px){
  .nav-caption{display:block}
  .footer-top{grid-template-columns:minmax(13rem,.85fr) minmax(0,2fr);gap:3rem}
  .grid--split{grid-template-columns:repeat(12,minmax(0,1fr))}
  .grid--split > .grid__main{grid-column:span 8}
  .grid--split > .grid__aside{grid-column:span 4}
}
@media (max-width:899px){
  .brand-tag{display:none}
  .header-top__inner{
    flex-wrap:nowrap;overflow-x:auto;gap:1rem;
    scrollbar-width:none;
  }
  .header-top__inner::-webkit-scrollbar{display:none}
  .quick-actions{margin-left:auto}
  .nav-brand{
    display:inline-block;color:var(--paper);
    font-weight:700;font-size:.95rem;letter-spacing:.06em;
  }
  .nav-toggle{display:inline-flex}
  .header-main{position:relative}
  .site-nav{
    position:absolute;left:0;right:0;top:100%;
    background:var(--ink-700);
    border-bottom:1px solid var(--line-soft);
    box-shadow:0 24px 44px -26px rgba(0,0,0,.95);
    opacity:0;visibility:hidden;transform:translateY(-.5rem);
    transition:transform .22s var(--ease),opacity .22s var(--ease),visibility .22s var(--ease);
  }
  .site-nav[data-open]{opacity:1;visibility:visible;transform:none}
  .nav-list{display:block;padding:.35rem var(--gutter) .9rem}
  .nav-item{flex:none;border-bottom:1px solid var(--line-soft)}
  .nav-item:last-child{border-bottom:0}
  .nav-link{padding:.85rem .25rem .85rem .85rem;border-left:2px solid transparent;font-size:1rem}
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{border-left-color:var(--amber);background:rgba(228,145,58,.08)}
}

@media (min-width:1180px){
  .help-handle{display:none}
  .help-dock{
    left:auto;bottom:auto;
    top:8.6rem;
    right:max(1.25rem,calc((100vw - 1280px) / 2));
    width:var(--dock-w);
    max-height:calc(100vh - 10.6rem);
    padding:1.25rem 1.15rem;
    border-top:1px solid var(--line-celadon);
    border-radius:1rem;
    transform:none;visibility:visible;
    box-shadow:0 26px 64px -34px rgba(0,0,0,.9);
  }
  .site-header[data-scrolled="true"] ~ * .help-dock,
  .site-header[data-scrolled="true"] + * .help-dock{top:4.9rem}
  .help-dock[data-open]{transform:none}
  #main-content{padding-right:calc(var(--dock-w) + 3.5rem)}
  .footer-inner{padding-right:calc(var(--dock-w) + 3.5rem)}
  .to-top{bottom:1.5rem;right:1.5rem}
}

/* 页头收起时帮助栏上移（帮助栏位于页脚，用 :has 兜底 + 属性选择器） */
@media (min-width:1180px){
  body:has(.site-header[data-scrolled="true"]) .help-dock{top:4.9rem}
}

/* ---------- 16 无障碍与动效偏好 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    transition-duration:.01ms!important;
    animation-duration:.01ms!important;
    animation-iteration-count:1!important;
  }
  .site-header[data-scrolled="true"] .header-top{max-height:0;opacity:0}
}