/* ============================================================
   365在线站 · 共享样式 /assets/site.css
   分区：变量 / 基础 / 版式 / 组件 / 页头 / 页脚 / 响应式
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,*::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,dd,time{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%;height:auto}
button{font:inherit;color:inherit;background:none;border:0}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:2px solid var(--amber);outline-offset:2px}

/* ---------- 2. 变量 ---------- */
:root{
  --ink:#16213E;
  --ink-2:#1F2B46;
  --amber:#E8871E;
  --amber-soft:#F6C177;
  --celadon:#2F9E8F;
  --celadon-soft:#A8DAD2;
  --paper:#F5F2EA;
  --white:#FFFFFF;
  --graphite:#12151C;
  --wine:#8C2F39;
  --gray:#6B7280;

  --line-dark:rgba(168,218,210,.32);
  --line-dark-soft:rgba(168,218,210,.16);
  --line-light:rgba(22,33,62,.16);
  --line-light-soft:rgba(22,33,62,.08);
  --text-on-ink:rgba(245,242,234,.82);
  --text-on-ink-dim:rgba(245,242,234,.52);

  --rail:96px;
  --header-h:64px;
  --header-h-slim:52px;
  --maxw:1160px;
  --maxw-wide:1320px;

  --font-display:"HarmonyOS Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-body:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;
}

/* ---------- 3. 基础 ---------- */
body{
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.9;
  color:var(--graphite);
  background:var(--paper);
  min-height:100vh;
}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:600;letter-spacing:-.02em;line-height:1.25}
h1{font-size:44px}
h2{font-size:22px}
h3{font-size:19px}
.mono{font-family:var(--font-mono);font-size:.94em;letter-spacing:.04em}
.u-amber{color:var(--amber)}
.u-celadon{color:var(--celadon)}
.u-gray{color:var(--gray)}
::selection{background:var(--amber-soft);color:var(--ink)}

/* ---------- 4. 版式与容器 ---------- */
.shell{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 24px}
.shell--wide{max-width:var(--maxw-wide)}
.band{padding:88px 0}
.band--ink{background:var(--ink);color:var(--paper)}
.band--ink h1,.band--ink h2,.band--ink h3{color:var(--paper)}
.band--paper{background:var(--paper)}
.band--white{background:var(--white)}
.band--celadon{background:var(--celadon-soft);color:var(--ink)}

.rail-layout{display:grid;grid-template-columns:var(--rail) minmax(0,1fr);gap:32px;align-items:start}
.rail{
  position:sticky;top:calc(var(--header-h) + 28px);align-self:start;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.16em;
  color:var(--celadon);padding-top:6px;
}

.section-index{
  font-family:var(--font-mono);font-size:13px;letter-spacing:.18em;
  color:var(--celadon);text-transform:uppercase;
}
.band--ink .section-index{color:var(--amber-soft)}
.section-title{font-size:36px;margin-top:10px}
.lede{font-size:19px;line-height:1.85;max-width:62ch;color:var(--gray)}
.band--ink .lede{color:var(--text-on-ink)}

.chapter{position:relative;padding-left:0}
.chapter__index{
  display:block;font-family:var(--font-mono);font-size:13px;letter-spacing:.18em;
  color:var(--amber);margin-bottom:10px;
}
.chapter__title{font-size:22px;margin-bottom:14px}

.prose{max-width:70ch;font-size:17px;line-height:1.9}
.prose--wide{max-width:84ch}
.prose p{margin:0 0 1em}
.prose h2{font-size:22px;margin:2em 0 .7em}
.prose h3{font-size:19px;margin:1.7em 0 .6em}
.prose ul,.prose ol{margin:0 0 1em;padding-left:1.4em;list-style:disc}
.prose ol{list-style:decimal}
.prose li{margin:.4em 0}
.prose a{color:var(--ink);border-bottom:1px solid var(--celadon);transition:border-color .16s ease,color .16s ease}
.prose a:hover{color:var(--celadon);border-bottom-color:var(--amber)}
.prose code{font-family:var(--font-mono);font-size:.9em;background:rgba(47,158,143,.1);padding:2px 6px;border-radius:2px}
.band--ink .prose{color:var(--text-on-ink)}

.divider{height:1px;border:0;margin:48px 0;background:var(--line-light)}
.band--ink .divider{background:var(--line-dark)}

.side-label{
  writing-mode:vertical-rl;font-family:var(--font-mono);font-size:12px;
  letter-spacing:.28em;color:var(--gray);
}

/* ---------- 5. 通用组件 ---------- */
.skip-link{
  position:absolute;left:16px;top:-56px;z-index:90;
  background:var(--amber);color:var(--ink);
  padding:10px 16px;border-radius:2px;font-size:14px;
  transition:top .16s ease;
}
.skip-link:focus{top:12px}

.btn{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-display);font-size:15px;letter-spacing:.02em;
  padding:12px 20px;border-radius:2px;border:1px solid transparent;
  cursor:pointer;transition:background-color .16s ease,color .16s ease,border-color .16s ease;
}
.btn--primary{background:var(--amber);color:var(--ink);border-color:var(--amber)}
.btn--primary:hover{background:var(--amber-soft);border-color:var(--amber-soft)}
.btn--ghost{background:transparent;color:var(--paper);border-color:var(--line-dark)}
.btn--ghost:hover{border-color:var(--amber);color:var(--amber-soft)}
.btn--ink{background:var(--ink);color:var(--paper);border-color:var(--ink)}
.btn--ink:hover{background:var(--ink-2);border-color:var(--celadon);color:var(--celadon-soft)}
.btn--line{background:transparent;color:var(--graphite);border-color:var(--line-light)}
.btn--line:hover{border-color:var(--amber);color:var(--amber)}

.frame{position:relative;border:1px solid var(--line-dark);padding:36px 32px}
.frame::before{
  content:"";position:absolute;inset:-1px;pointer-events:none;
  background:
    linear-gradient(var(--amber),var(--amber)) left top/16px 2px no-repeat,
    linear-gradient(var(--amber),var(--amber)) left top/2px 16px no-repeat,
    linear-gradient(var(--amber),var(--amber)) right top/16px 2px no-repeat,
    linear-gradient(var(--amber),var(--amber)) right top/2px 16px no-repeat,
    linear-gradient(var(--amber),var(--amber)) left bottom/16px 2px no-repeat,
    linear-gradient(var(--amber),var(--amber)) left bottom/2px 16px no-repeat,
    linear-gradient(var(--amber),var(--amber)) right bottom/16px 2px no-repeat,
    linear-gradient(var(--amber),var(--amber)) right bottom/2px 16px no-repeat;
}
.frame--light{border-color:var(--line-light)}

.card{
  display:block;background:var(--white);border:1px solid var(--line-light);
  border-radius:2px;padding:28px;
  transition:background-color .16s ease,border-color .16s ease;
}
.card:hover,.card:focus-visible{background:#FBF8F1;border-color:var(--celadon)}
.card__meta{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--gray);transition:color .16s ease}
.card:hover .card__meta{color:var(--amber)}
.card__title{font-family:var(--font-display);font-size:22px;font-weight:600;letter-spacing:-.02em;margin:10px 0 8px}
.card__text{font-size:15px;line-height:1.8;color:var(--gray)}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;
  padding:3px 8px;border:1px solid var(--celadon);color:var(--celadon);
  border-radius:2px;background:transparent;
}
.tag--amber{border-color:var(--amber);color:var(--amber)}
.tag--celadon{border-color:var(--celadon);color:var(--celadon)}
.tag--wine{border-color:var(--wine);color:var(--wine)}

.breadcrumb{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--gray)}
.breadcrumb a{border-bottom:1px solid transparent;transition:color .16s ease,border-color .16s ease}
.breadcrumb a:hover{color:var(--celadon);border-bottom-color:var(--celadon)}
.breadcrumb__sep{color:var(--celadon-soft)}
.breadcrumb [aria-current="page"]{color:var(--graphite)}

.stat{display:flex;flex-direction:column;gap:4px}
.stat__value{font-family:var(--font-mono);font-size:34px;letter-spacing:-.01em;color:var(--amber);line-height:1.1}
.stat__label{font-size:14px;color:var(--gray)}

.timeline{list-style:none;margin:0;padding:0;position:relative}
.timeline::before{content:"";position:absolute;left:7px;top:8px;bottom:8px;width:1px;background:var(--line-dark)}
.timeline__item{position:relative;padding:0 0 32px 34px}
.timeline__item::before{
  content:"";position:absolute;left:0;top:8px;width:15px;height:15px;border-radius:50%;
  border:2px solid var(--celadon);background:var(--paper);
  transition:border-color .16s ease,background-color .16s ease;
}
.timeline__item:hover::before,.timeline__item:focus-within::before{border-color:var(--amber);background:var(--amber-soft)}
.timeline__time{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--gray)}
.timeline__body{margin-top:6px;font-size:16px;line-height:1.85}

.media{
  position:relative;overflow:hidden;border-radius:2px;
  border:1px solid var(--line-dark);background:var(--ink-2);
  aspect-ratio:var(--media-ratio,16 / 10);
}
.media > img,.media > svg{width:100%;height:100%;object-fit:cover}
.media--wide{--media-ratio:21 / 9}
.media--tall{--media-ratio:3 / 4}
.media--square{--media-ratio:1 / 1}
.media__label{
  position:absolute;left:12px;bottom:12px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--celadon-soft);
}
.media__caption{margin-top:10px;font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;color:var(--gray)}

/* ---------- 6. 页头 ---------- */
.site-header{
  position:sticky;top:0;z-index:60;
  background:var(--ink);color:var(--paper);
  border-bottom:1px solid var(--line-dark);
}
.site-header::after{
  content:"";position:absolute;left:0;right:0;bottom:-5px;height:5px;pointer-events:none;
  background-image:repeating-linear-gradient(90deg,rgba(168,218,210,.42) 0 1px,transparent 1px 16px);
  opacity:.5;
}
.site-header__inner{
  position:relative;
  width:100%;max-width:var(--maxw);margin:0 auto;padding:0 24px;
  min-height:var(--header-h);
  display:flex;align-items:center;gap:28px;
  transition:min-height .16s ease;
}
.brand{display:flex;flex-direction:column;gap:2px;min-width:0}
.brand__link{display:flex;align-items:baseline;gap:8px}
.brand__name{font-family:var(--font-display);font-size:20px;font-weight:600;letter-spacing:-.02em;color:var(--paper)}
.brand__tag{font-size:12px;letter-spacing:.16em;color:var(--celadon-soft)}
.brand__stamp{display:flex;align-items:center;gap:8px;font-family:var(--font-mono);font-size:11px;letter-spacing:.06em;color:var(--text-on-ink-dim)}
.brand__stamp-label{color:var(--celadon)}
.brand__stamp-value{color:var(--text-on-ink-dim)}

.site-nav{margin-left:auto;display:flex;align-items:center;gap:24px;transition:opacity .16s ease}
.site-nav__group{display:none}
.site-nav__list{display:flex;align-items:center;gap:22px}
.site-nav__list + .site-nav__list{padding-left:22px;border-left:1px solid var(--line-dark)}
.site-nav__list a{
  position:relative;display:inline-block;padding:6px 2px;
  font-size:15px;color:var(--text-on-ink);
  transition:color .16s ease;
}
.site-nav__list a::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:2px;
  background:var(--amber);transform:scaleX(0);transform-origin:left center;
  transition:transform .16s ease;
}
.site-nav__list a:hover{color:var(--white)}
.site-nav__list a:hover::after{transform:scaleX(1)}
.site-nav__list a[aria-current="page"]{color:var(--white)}
.site-nav__list a[aria-current="page"]::after{transform:scaleX(1)}
.site-nav__list--util a{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--text-on-ink-dim)}
.site-nav__list--util a[aria-current="page"]{color:var(--amber-soft)}
.site-nav__list--util a[aria-current="page"]::after{background:var(--celadon)}

.header-shortcut{
  display:none;align-items:center;margin-left:auto;
  padding:8px 14px;border:1px solid var(--celadon);border-radius:2px;
  font-size:14px;letter-spacing:.04em;color:var(--celadon-soft);
  transition:border-color .16s ease,color .16s ease;
}
.header-shortcut:hover{border-color:var(--amber);color:var(--amber-soft)}

.nav-toggle{
  display:none;align-items:center;gap:10px;margin-left:auto;
  padding:8px 12px;border:1px solid var(--line-dark);border-radius:2px;
  color:var(--paper);font-family:var(--font-mono);font-size:13px;letter-spacing:.1em;
  cursor:pointer;transition:border-color .16s ease,color .16s ease;
}
.nav-toggle:hover{border-color:var(--amber);color:var(--amber-soft)}
.nav-toggle__bars{position:relative;width:16px;height:2px;background:currentColor;transition:background-color .16s ease}
.nav-toggle__bars::before,.nav-toggle__bars::after{
  content:"";position:absolute;left:0;width:16px;height:2px;background:currentColor;
  transition:transform .16s ease;
}
.nav-toggle__bars::before{top:-5px}
.nav-toggle__bars::after{top:5px}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-5px) rotate(-45deg)}

.scroll-rail{position:absolute;left:0;right:0;bottom:-1px;height:2px;pointer-events:none;background:transparent}
.scroll-rail__bar{display:block;height:100%;width:100%;background:var(--amber);transform:scaleX(0);transform-origin:left center}

/* ---------- 7. 页脚 ---------- */
.site-footer{background:var(--paper);color:var(--graphite);border-top:1px solid var(--line-light)}
.site-footer__inner{
  width:100%;max-width:var(--maxw);margin:0 auto;padding:64px 24px 44px;
  display:grid;grid-template-columns:1.1fr 1.5fr 1.1fr;gap:48px;align-items:start;
}
.footer-brand{font-family:var(--font-display);font-size:22px;font-weight:600;letter-spacing:-.02em}
.footer-tagline{margin:10px 0 16px;font-size:14px;color:var(--gray)}
.footer-icp{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--gray)}

.footer-heading{font-family:var(--font-mono);font-size:12px;letter-spacing:.18em;color:var(--celadon);margin-bottom:14px}
.footer-links{display:grid;grid-template-columns:1fr 1fr;gap:32px}
.footer-group + .footer-group{margin-top:0}
.footer-list{display:flex;flex-direction:column;gap:10px}
.footer-list a{font-size:15px;color:var(--graphite);border-bottom:1px solid transparent;transition:color .16s ease,border-color .16s ease}
.footer-list a:hover{color:var(--amber);border-bottom-color:var(--amber)}

.footer-contact{display:flex;flex-direction:column;gap:14px}
.footer-contact__item{display:flex;flex-direction:column;gap:2px}
.footer-contact__label{font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;color:var(--celadon)}
.footer-contact__value{font-family:var(--font-mono);font-size:14px;line-height:1.7;color:var(--graphite);word-break:break-all}
.to-top{
  margin-top:20px;align-self:flex-start;
  padding:9px 16px;border:1px solid var(--line-light);border-radius:2px;
  font-size:14px;color:var(--graphite);cursor:pointer;
  transition:border-color .16s ease,color .16s ease,background-color .16s ease;
}
.to-top:hover{border-color:var(--amber);color:var(--amber);background:rgba(232,135,30,.06)}

.site-footer__base{
  width:100%;max-width:var(--maxw);margin:0 auto;padding:20px 24px 40px;
  border-top:1px solid var(--line-light-soft);
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:14px;align-items:center;
}
.footer-fineprint{font-size:13px;color:var(--gray);max-width:62ch}
.footer-copy{font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;color:var(--gray)}

/* ---------- 8. 响应式 ---------- */
@media (max-width:1024px){
  h1{font-size:36px}
  .section-title{font-size:30px}
  .site-footer__inner{grid-template-columns:1fr 1fr;gap:40px}
  .site-footer__col--brand{grid-column:1 / -1}
}
@media (max-width:960px){
  .rail-layout{grid-template-columns:minmax(0,1fr);gap:20px}
  .rail{display:none}
  .nav-toggle{display:inline-flex}
  .header-shortcut{display:none !important}
  .site-nav{
    position:fixed;top:var(--header-h);left:0;bottom:0;
    width:min(84vw,340px);
    display:flex;flex-direction:column;align-items:stretch;gap:0;
    margin-left:0;padding:24px 24px 48px;
    background:var(--ink-2);border-right:1px solid var(--line-dark);
    transform:translateX(-101%);
    transition:transform .24s ease;
    overflow-y:auto;overscroll-behavior:contain;
    visibility:hidden;
  }
  .site-nav[data-open="true"]{transform:translateX(0);visibility:visible}
  .site-nav__group{
    display:block;font-family:var(--font-mono);font-size:12px;letter-spacing:.18em;
    color:var(--celadon-soft);margin:22px 0 6px;
  }
  .site-nav__group:first-child{margin-top:0}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .site-nav__list + .site-nav__list{padding-left:0;border-left:0}
  .site-nav__list a{
    display:block;width:100%;padding:13px 0;font-size:17px;
    border-bottom:1px solid var(--line-dark-soft);
  }
  .site-nav__list a::after{display:none}
  .site-nav__list a[aria-current="page"]{color:var(--amber-soft);padding-left:14px;border-left:2px solid var(--amber)}
  .site-nav__list--util a{font-size:15px;font-family:var(--font-body);color:var(--text-on-ink)}
}
@media (max-width:640px){
  body{font-size:16px;line-height:1.85}
  h1{font-size:30px}
  .section-title{font-size:26px}
  .lede{font-size:17px}
  .band{padding:56px 0}
  .shell,.site-header__inner,.site-footer__inner,.site-footer__base{padding-left:18px;padding-right:18px}
  .frame{padding:24px 18px}
  .brand__stamp{display:none}
  .site-footer__inner{grid-template-columns:1fr;gap:32px;padding-top:44px}
  .footer-links{grid-template-columns:1fr 1fr;gap:24px}
  .site-footer__base{flex-direction:column;align-items:flex-start}
}
@media (min-width:961px){
  .site-header[data-scrolled="true"] .site-header__inner{min-height:var(--header-h-slim)}
  .site-header[data-scrolled="true"] .brand__stamp{display:none}
  .site-header[data-scrolled="true"] .site-nav{
    position:absolute;right:24px;top:50%;transform:translateY(-50%);
    opacity:0;visibility:hidden;pointer-events:none;
  }
  .site-header[data-scrolled="true"] .header-shortcut{display:inline-flex}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.01ms !important;
    transition-delay:0ms !important;
  }
}