/* ===========================================================
   凡国网址 · site.css
   共享层：reset / 变量 / 中文排版 / 刊头 / 页脚 / 通用组件
   =========================================================== */

:root{
  --ink-950:#0C1620;
  --ink-800:#172833;
  --ink-600:#33475A;
  --slate-500:#5C6F7F;
  --line-200:#DCE2E7;
  --paper-50:#F5F6F7;
  --white:#FFFFFF;
  --amber-500:#E07B1F;
  --amber-700:#A0500B;
  --amber-050:#FBEEDF;
  --celadon-600:#2A8071;
  --celadon-050:#E4F1ED;

  --text-muted:var(--slate-500);
  --hairline:1px solid var(--line-200);

  --font-head:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",Georgia,serif;
  --font-ui:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","SF Mono",ui-monospace,Menlo,Consolas,"Liberation Mono",monospace;

  --container:1180px;
  --container-wide:1340px;
  --gutter:clamp(16px,3.2vw,34px);
  --radius:4px;
  --shadow-1:0 1px 2px rgba(12,22,32,.07);
  --shadow-2:0 10px 28px rgba(12,22,32,.10);
  --ease:cubic-bezier(.22,.61,.36,1);
  --dur:260ms;
}

*,*::before,*::after{box-sizing:border-box}

html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}

body{
  margin:0;
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  color:var(--ink-950);
  background-color:var(--paper-50);
  background-image:
    linear-gradient(to right,rgba(92,111,127,.05) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(92,111,127,.05) 1px,transparent 1px);
  background-size:24px 24px;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3,h4{
  font-family:var(--font-head);
  font-weight:700;
  line-height:1.2;
  letter-spacing:-.01em;
  margin:0 0 .6em;
}

p{margin:0 0 1em}
p:last-child{margin-bottom:0}

a{color:var(--amber-700);text-decoration:none}
a:hover{text-decoration:underline}

ul,ol{margin:0 0 1em;padding-left:1.2em}

img{max-width:100%;height:auto}

button{font:inherit;color:inherit}

strong{font-weight:700}

::selection{background:var(--amber-050);color:var(--ink-950)}

:focus-visible{
  outline:2px solid var(--amber-500);
  outline-offset:3px;
}

/* ---------- 排版工具 ---------- */
.mono{font-family:var(--font-mono)}

/* ---------- 跳转链接 ---------- */
.skip-link{
  position:absolute;
  left:16px;
  top:-80px;
  z-index:400;
  display:inline-block;
  padding:12px 20px;
  background:var(--amber-500);
  color:#fff;
  font-family:var(--font-ui);
  font-size:13px;
  font-weight:600;
  letter-spacing:.06em;
  border-radius:0 0 var(--radius) var(--radius);
  text-decoration:none;
  transition:top .2s var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{top:0;text-decoration:none}

/* ===========================================================
   刊头
   =========================================================== */
.site-header{
  position:sticky;
  top:0;
  z-index:120;
  background:var(--ink-950);
  color:var(--paper-50);
  border-bottom:1px solid var(--ink-600);
}

.scroll-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-1px;
  height:2px;
  pointer-events:none;
  background:rgba(255,255,255,.07);
}
.scroll-progress__bar{
  display:block;
  width:0;
  height:100%;
  background:var(--amber-500);
  transform-origin:left center;
}

.masthead{position:relative}

.masthead__inner{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);
  align-items:center;
  gap:16px;
  max-width:var(--container-wide);
  margin:0 auto;
  padding:14px var(--gutter);
  transition:padding var(--dur) var(--ease);
}

.site-header[data-condensed] .masthead__inner{padding-top:7px;padding-bottom:7px}

/* 左侧等宽坐标 */
.masthead__coord{
  display:flex;
  align-items:center;
  gap:16px;
  margin:0;
  justify-self:start;
  font-family:var(--font-mono);
  font-size:11px;
  line-height:1.4;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:rgba(255,255,255,.62);
}
.coord-item{display:inline-flex;align-items:center;gap:6px}
.coord-item__key{color:var(--amber-500);letter-spacing:.16em}
.coord-item__val{color:rgba(255,255,255,.72)}

/* 品牌 */
.brand{
  display:inline-flex;
  flex-direction:column;
  align-items:center;
  gap:2px;
  justify-self:center;
  text-decoration:none;
  color:var(--paper-50);
  padding:2px 6px;
}
.brand:hover{text-decoration:none}
.brand__name{
  font-family:var(--font-head);
  font-weight:700;
  font-size:clamp(19px,2.2vw,26px);
  line-height:1.15;
  letter-spacing:.2em;
  text-indent:.2em;
  color:#fff;
}
.brand__meta{
  font-family:var(--font-mono);
  font-size:9.5px;
  letter-spacing:.28em;
  text-transform:uppercase;
  color:var(--amber-500);
}

/* 右侧工具 */
.header-actions{
  display:flex;
  align-items:center;
  gap:14px;
  justify-self:end;
}
.header-link{
  font-family:var(--font-ui);
  font-size:13px;
  letter-spacing:.06em;
  color:rgba(255,255,255,.76);
  text-decoration:none;
  padding-bottom:2px;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
  white-space:nowrap;
}
.header-link:hover,
.header-link:focus-visible{color:#fff;border-bottom-color:var(--amber-500);text-decoration:none}

/* 移动导航按钮 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:9px 14px;
  background:transparent;
  border:1px solid var(--ink-600);
  border-radius:999px;
  color:var(--paper-50);
  font-family:var(--font-ui);
  font-size:12px;
  letter-spacing:.14em;
  cursor:pointer;
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--amber-500);color:#fff}
.nav-toggle__bars{position:relative;display:block;width:16px;height:11px}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;right:0;
  height:1.5px;
  background:currentColor;
  transition:transform .22s var(--ease);
}
.nav-toggle__bars::before{top:1px}
.nav-toggle__bars::after{bottom:1px}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(3.75px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-3.75px) rotate(-45deg)}
.nav-toggle__label{line-height:1}

/* ===========================================================
   导航（桌面：居中横向索引带）
   =========================================================== */
.site-nav{
  background:var(--ink-950);
  border-top:1px solid var(--ink-800);
}

.site-nav__inner{
  display:flex;
  align-items:center;
  justify-content:flex-start;
  max-width:var(--container-wide);
  margin:0 auto;
  padding:0 var(--gutter);
  overflow-x:auto;
  scrollbar-width:none;
  -ms-overflow-style:none;
}
.site-nav__inner::-webkit-scrollbar{display:none}

.site-nav__list{
  display:flex;
  align-items:center;
  gap:clamp(2px,1.5vw,24px);
  margin:0 auto;
  padding:0;
  list-style:none;
}
.site-nav__item{flex:0 0 auto;display:flex;align-items:center}

.site-nav__link{
  position:relative;
  display:inline-block;
  padding:13px 6px;
  font-family:var(--font-ui);
  font-size:14px;
  letter-spacing:.05em;
  color:rgba(255,255,255,.74);
  white-space:nowrap;
  text-decoration:none;
  transition:color .2s var(--ease);
}
.site-nav__link::after{
  content:"";
  position:absolute;
  left:6px;right:6px;bottom:7px;
  height:2px;
  background:var(--amber-500);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .24s var(--ease);
}
.site-nav__link:hover{color:#fff;text-decoration:none}
.site-nav__link:hover::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:#fff}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1)}

/* 平板资料库胶囊 */
.site-nav__pill{
  display:inline-flex;
  align-items:center;
  gap:7px;
  padding:7px 14px;
  margin-right:6px;
  border:1px solid var(--celadon-600);
  border-radius:999px;
  background:rgba(42,128,113,.16);
  color:var(--celadon-050);
  font-family:var(--font-ui);
  font-size:12.5px;
  font-weight:600;
  letter-spacing:.08em;
  white-space:nowrap;
  text-decoration:none;
  transition:background-color .2s var(--ease),border-color .2s var(--ease),color .2s var(--ease);
}
.site-nav__pill:hover,
.site-nav__pill:focus-visible{
  background:rgba(42,128,113,.34);
  border-color:var(--celadon-050);
  color:#fff;
  text-decoration:none;
}
.site-nav__pill-dot{
  width:6px;height:6px;
  border-radius:50%;
  background:var(--celadon-050);
  flex:0 0 auto;
}

/* 抽屉底部动作区（默认桌面隐藏） */
.site-nav__foot{display:none}
.site-nav__foot-link{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.12em;
  color:rgba(255,255,255,.72);
  text-decoration:none;
  padding:6px 0;
}
.site-nav__foot-link:hover{color:#fff;text-decoration:none}

/* ===========================================================
   按钮
   =========================================================== */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5em;
  padding:12px 20px;
  border:1px solid transparent;
  border-radius:var(--radius);
  font-family:var(--font-ui);
  font-size:14px;
  font-weight:600;
  line-height:1;
  letter-spacing:.04em;
  text-align:center;
  text-decoration:none;
  cursor:pointer;
  transition:background-color .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease),transform .2s var(--ease);
}
.btn:hover{text-decoration:none}
.btn:active{transform:translateY(1px)}

.btn--sm{padding:9px 15px;font-size:13px}
.btn--block{display:flex;width:100%}

.btn--accent{background:var(--amber-500);border-color:var(--amber-500);color:#fff}
.btn--accent:hover{background:var(--amber-700);border-color:var(--amber-700);color:#fff}

.btn--ghost{background:transparent;border-color:var(--line-200);color:var(--ink-950)}
.btn--ghost:hover{border-color:var(--ink-950);color:var(--ink-950)}

.btn--dark{background:var(--ink-950);border-color:var(--ink-950);color:#fff}
.btn--dark:hover{background:var(--ink-800);border-color:var(--ink-800);color:#fff}

/* ===========================================================
   页脚
   =========================================================== */
.site-footer{
  background:var(--ink-950);
  color:rgba(255,255,255,.74);
  font-family:var(--font-ui);
  font-size:13.5px;
  line-height:1.75;
  border-top:1px solid var(--ink-600);
  margin-top:56px;
}

.footer__inner{
  display:grid;
  grid-template-columns:1.7fr repeat(4,minmax(0,1fr));
  gap:34px 30px;
  max-width:var(--container-wide);
  margin:0 auto;
  padding:clamp(32px,4vw,52px) var(--gutter) 36px;
}

.footer__brand{min-width:0}
.footer__brand-link{
  display:inline-block;
  font-family:var(--font-head);
  font-weight:700;
  font-size:22px;
  letter-spacing:.2em;
  color:#fff;
  text-decoration:none;
  padding-bottom:4px;
  border-bottom:2px solid var(--amber-500);
}
.footer__brand-link:hover{text-decoration:none;color:#fff}
.footer__brand-meta{
  margin:12px 0 10px;
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--amber-500);
}
.footer__note{
  margin:0 0 16px;
  max-width:26em;
  color:rgba(255,255,255,.6);
  font-size:13px;
}
.footer__cta{
  color:var(--paper-50);
  border-color:var(--ink-600);
  background:transparent;
}
.footer__cta:hover{
  color:#fff;
  border-color:var(--amber-500);
  background:rgba(224,123,31,.12);
}

.footer__col{min-width:0}
.footer__col--contact{grid-column:auto}

.footer__title{
  margin:0 0 14px;
  padding-bottom:9px;
  border-bottom:1px solid var(--ink-600);
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:rgba(255,255,255,.55);
}

.footer__list{
  margin:0;
  padding:0;
  list-style:none;
}
.footer__list li{
  padding:5px 0;
  word-break:break-word;
}
.footer__list a{
  color:rgba(255,255,255,.82);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.footer__list a:hover,
.footer__list a:focus-visible{
  color:#fff;
  border-bottom-color:var(--amber-500);
  text-decoration:none;
}

.footer__mono{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.04em;
  color:rgba(255,255,255,.66);
}

.footer__legal{
  border-top:1px solid var(--ink-800);
  background:rgba(23,40,51,.55);
}
.footer__legal-inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  max-width:var(--container-wide);
  margin:0 auto;
  padding:16px var(--gutter) 20px;
}
.footer__copy{
  margin:0;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:rgba(255,255,255,.55);
}
.footer__legal-links{
  display:flex;
  flex-wrap:wrap;
  gap:6px 20px;
  margin:0;
  padding:0;
  list-style:none;
  font-size:12.5px;
}
.footer__legal-links a{
  color:rgba(255,255,255,.7);
  text-decoration:none;
  letter-spacing:.04em;
}
.footer__legal-links a:hover,
.footer__legal-links a:focus-visible{color:var(--amber-500);text-decoration:none}

/* ===========================================================
   通用内容组件
   =========================================================== */
.container{
  width:100%;
  max-width:var(--container);
  margin:0 auto;
  padding-left:var(--gutter);
  padding-right:var(--gutter);
}
.container--wide{max-width:var(--container-wide)}

/* 面包屑 */
.breadcrumbs{
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.1em;
  color:var(--text-muted);
  padding:18px 0 0;
}
.breadcrumbs ol{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin:0;
  padding:0;
  list-style:none;
}
.breadcrumbs li{display:inline-flex;align-items:center;gap:8px}
.breadcrumbs li + li::before{
  content:"/";
  color:var(--line-200);
  font-family:var(--font-mono);
}
.breadcrumbs a{color:var(--text-muted);text-decoration:none}
.breadcrumbs a:hover{color:var(--amber-700);text-decoration:none}
.breadcrumbs [aria-current="page"]{color:var(--ink-950)}

/* 章节头 */
.section-head{
  display:flex;
  align-items:baseline;
  flex-wrap:wrap;
  gap:10px 14px;
  padding-bottom:12px;
  margin-bottom:22px;
  border-bottom:var(--hairline);
}
.section-head__index{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.16em;
  color:var(--amber-700);
}
.section-head__title{
  margin:0;
  font-family:var(--font-head);
  font-weight:700;
  font-size:clamp(20px,2.4vw,26px);
  letter-spacing:-.01em;
}
.section-head__note{
  margin-left:auto;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--text-muted);
}

/* 标签 */
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border:1px solid var(--line-200);
  border-radius:999px;
  background:var(--white);
  color:var(--ink-600);
  font-family:var(--font-mono);
  font-size:11px;
  line-height:1.5;
  letter-spacing:.1em;
  text-transform:uppercase;
  white-space:nowrap;
}
.tag--new{
  background:var(--celadon-050);
  border-color:var(--celadon-600);
  color:var(--celadon-600);
}
.tag--diff{
  background:var(--amber-050);
  border-color:var(--amber-500);
  color:var(--amber-700);
}
.tag--solid{
  background:var(--amber-500);
  border-color:var(--amber-500);
  color:#fff;
}

/* 卡片 */
.card{
  background:var(--white);
  border:var(--hairline);
  border-radius:var(--radius);
  box-shadow:var(--shadow-1);
  padding:20px;
}
.card--pad-lg{padding:28px}
.card--ink{
  background:var(--ink-800);
  border-color:var(--ink-600);
  color:var(--paper-50);
  box-shadow:none;
}
.card__title{
  margin:0 0 8px;
  font-family:var(--font-head);
  font-weight:700;
  font-size:18px;
  letter-spacing:-.01em;
}
.card__meta{
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.1em;
  color:var(--text-muted);
}
.card--ink .card__meta{color:rgba(255,255,255,.6)}

/* Bento 容器：1px 细线缝 */
.bento{
  display:grid;
  gap:1px;
  background:var(--line-200);
  border:var(--hairline);
  border-radius:var(--radius);
  overflow:hidden;
}
.bento > *{
  background:var(--white);
  padding:22px;
  min-width:0;
}
.bento > .card--ink{background:var(--ink-800)}

/* 索引列表 */
.index-list{
  margin:0;
  padding:0;
  list-style:none;
  border-top:var(--hairline);
}
.index-list li{
  display:flex;
  align-items:baseline;
  gap:14px;
  padding:12px 8px;
  border-bottom:var(--hairline);
  transition:background-color .18s var(--ease);
}
.index-list li:hover{background:var(--amber-050)}
.index-list__num{
  flex:0 0 auto;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--slate-500);
}

/* 图片容器基础规则（页面阶段放入图片即可） */
.image-frame{
  position:relative;
  display:block;
  overflow:hidden;
  border:var(--hairline);
  border-radius:var(--radius);
  background-color:var(--paper-50);
  background-image:
    linear-gradient(to right,rgba(92,111,127,.13) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(92,111,127,.13) 1px,transparent 1px);
  background-size:24px 24px;
}
.image-frame::before{
  content:"";
  display:block;
  padding-top:var(--frame-ratio,62.5%);
}
.image-frame > img,
.image-frame > picture > img{
  position:absolute;
  inset:0;
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}
.image-frame--wide{--frame-ratio:42%}
.image-frame--square{--frame-ratio:100%}
.image-frame--tall{--frame-ratio:128%}
.image-frame__tag{
  position:absolute;
  left:12px;
  top:12px;
  z-index:2;
}
.image-frame__caption{
  position:absolute;
  left:0;right:0;bottom:0;
  z-index:2;
  padding:26px 12px 10px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:#fff;
  background:linear-gradient(to top,rgba(12,22,32,.82),rgba(12,22,32,0));
}

/* 滚动浮现协议 */
.js-ready [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity .32s var(--ease),transform .32s var(--ease);
  transition-delay:var(--reveal-delay,0s);
  will-change:opacity,transform;
}
.js-ready [data-reveal].is-revealed{
  opacity:1;
  transform:none;
}

/* ===========================================================
   断点：桌面 / 平板 / 手机
   =========================================================== */
@media (max-width:1180px){
  .site-nav__list{gap:clamp(0px,1.2vw,16px)}
  .footer__inner{grid-template-columns:1.6fr repeat(4,minmax(0,1fr));gap:30px 22px}
}

@media (max-width:1099px){
  .footer__inner{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__brand{grid-column:1 / -1}
  .footer__col--contact{grid-column:1 / -1}
}

@media (max-width:899px){
  .site-header{position:sticky}
  .masthead__inner{
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:12px;
    padding:12px var(--gutter);
  }
  .masthead__coord{display:none}
  .brand{align-items:flex-start;justify-self:start;padding:0}
  .brand__name{font-size:19px;letter-spacing:.16em;text-indent:.16em}
  .brand__meta{font-size:9px}
  .header-actions{gap:10px;justify-self:end}
  .header-actions .header-link,
  .header-actions .btn{display:none}
  .nav-toggle{display:inline-flex}

  .site-nav{
    position:absolute;
    left:0;
    right:0;
    top:100%;
    border-top:1px solid var(--ink-600);
    border-bottom:1px solid var(--ink-600);
    box-shadow:0 20px 42px rgba(12,22,32,.5);
    max-height:calc(100vh - 68px);
    overflow-y:auto;
    visibility:hidden;
    opacity:0;
    transform:translateY(-10px);
    transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease),visibility var(--dur) var(--ease);
  }
  .site-nav[data-open]{
    visibility:visible;
    opacity:1;
    transform:none;
  }

  .site-nav__inner{
    flex-direction:column;
    align-items:stretch;
    padding:16px var(--gutter) 24px;
    overflow:visible;
  }
  .site-nav__list{
    flex-direction:column;
    align-items:stretch;
    gap:0;
    margin:0;
    width:100%;
  }
  .site-nav__item{
    border-bottom:1px solid var(--ink-800);
    padding:0;
  }
  .site-nav__item:first-child{
    border-bottom:0;
    padding:0 0 14px;
  }
  .site-nav__link{
    display:block;
    padding:14px 2px;
    font-size:15px;
    letter-spacing:.06em;
  }
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{
    color:#fff;
    padding-left:12px;
    border-left:2px solid var(--amber-500);
  }
  .site-nav__pill{margin-right:0}

  .site-nav__foot{
    display:flex;
    flex-direction:column;
    align-items:stretch;
    gap:12px;
    margin-top:20px;
    padding-top:18px;
    border-top:1px solid var(--ink-800);
  }
  .site-nav__foot-link{align-self:flex-start}
}

@media (max-width:600px){
  body{font-size:15px}
  .footer__inner{grid-template-columns:1fr;gap:26px}
  .footer__col--contact{grid-column:auto}
  .footer__legal-inner{flex-direction:column;align-items:flex-start;gap:10px}
  .section-head__note{margin-left:0;flex-basis:100%}
  .card{padding:16px}
  .bento > *{padding:16px}
}

/* ===========================================================
   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;
  }
  .js-ready [data-reveal]{opacity:1;transform:none}
}