/* ==========================================================================
   大阳城服务 — 共享样式 /assets/site.css
   信息桌面隐喻：编号索引 + 纸张底 + 深墨蓝阅读区
   ========================================================================== */

/* ---------- 1. Reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0}
h1,h2,h3,h4,h5,h6,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,picture,svg,video,canvas{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0;cursor:pointer}
a{color:inherit;text-decoration-thickness:1px;text-underline-offset:.22em}
table{border-collapse:collapse;width:100%}

/* ---------- 2. 设计令牌 ---------- */
:root{
  --ink:#0F2233;
  --ink-2:#1B3448;
  --sand:#C9A96A;
  --sand-soft:#E4D3AE;
  --clay:#C96A3D;
  --clay-deep:#B0592F;
  --paper:#F7F3EA;
  --paper-2:#ECE7DD;
  --slate:#6B7A86;
  --sea:#5E7C74;
  --white:#FFFFFF;

  --line:rgba(15,34,51,.14);
  --line-soft:rgba(15,34,51,.07);
  --on-ink:rgba(247,243,234,.78);
  --on-ink-soft:rgba(247,243,234,.55);
  --on-ink-line:rgba(228,211,174,.18);

  --font-title:'Songti SC','Noto Serif SC','Source Han Serif SC',serif;
  --font-body:'PingFang SC','Noto Sans SC','Source Han Sans SC',sans-serif;

  --shell:min(1160px,calc(100% - clamp(2rem,7vw,5rem)));
  --gutter:clamp(1.1rem,4vw,2.5rem);
  --header-h:74px;

  --r-lg:32px;
  --r-md:22px;
  --r-sm:14px;
  --r-pill:999px;

  --ease:cubic-bezier(.22,.61,.36,1);
  --dur:.24s;

  color-scheme:light;
}

/* ---------- 3. 中文排版基线 ---------- */
body{
  font-family:var(--font-body);
  font-size:clamp(16px,.6vw + 14px,17.5px);
  line-height:1.78;
  color:var(--ink);
  background:var(--paper);
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-wrap:break-word;
}
h1,h2,h3,h4,h5,h6{
  font-family:var(--font-title);
  font-weight:400;
  line-height:1.22;
  letter-spacing:.01em;
  text-wrap:balance;
}
p{text-wrap:pretty}
strong,b{font-weight:600}
small{font-size:.8125rem}
::selection{background:var(--sand-soft);color:var(--ink)}

.type-display{
  font-family:var(--font-title);
  font-weight:300;
  font-size:clamp(2.4rem,5vw,4.8rem);
  line-height:1.08;
  letter-spacing:-.01em;
}
.type-lede{
  font-size:clamp(1rem,1.2vw + .7rem,1.22rem);
  line-height:1.85;
  color:var(--slate);
  max-width:36ch;
}
.type-label{
  font-size:.72rem;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--slate);
}

/* ---------- 4. 工具类 ---------- */
.shell{width:var(--shell);margin-inline:auto}
.visually-hidden{
  position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);clip-path:inset(50%);white-space:nowrap;border:0;
}
#main-content{scroll-margin-top:calc(var(--header-h) + 18px)}

/* ---------- 5. 分区与网格 ---------- */
.section{padding-block:clamp(3.5rem,8vw,7rem)}
.section--tint{background:var(--paper-2)}
.section--ink{background:var(--ink);color:var(--paper)}
.section--ink .type-lede{color:var(--on-ink)}

.grid{display:grid;gap:clamp(1.5rem,4vw,3.5rem)}
.grid--split{grid-template-columns:minmax(0,5fr) minmax(0,7fr)}
.grid--aside{grid-template-columns:minmax(0,3fr) minmax(0,9fr)}
.grid--halves{grid-template-columns:repeat(2,minmax(0,1fr))}

.section-num{
  display:block;
  font-family:var(--font-title);
  font-weight:700;
  font-size:clamp(1.75rem,3.2vw,2.75rem);
  line-height:1;
  letter-spacing:.02em;
  color:var(--sand);
  font-variant-numeric:tabular-nums;
}
.section--ink .section-num{color:var(--sand-soft)}

/* ---------- 6. 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  padding:.7rem 1.35rem;border-radius:var(--r-pill);
  border:1px solid transparent;
  font-size:.9rem;font-weight:600;letter-spacing:.04em;
  text-decoration:none;cursor:pointer;
  transition:background-color var(--dur) var(--ease),
             color var(--dur) var(--ease),
             border-color var(--dur) var(--ease),
             transform var(--dur) var(--ease);
}
.btn--clay{background:var(--clay);color:var(--white)}
.btn--clay:hover{background:var(--clay-deep);transform:translateY(-1px)}
.btn--ghost{background:transparent;color:inherit;border-color:var(--sand)}
.btn--ghost:hover{background:rgba(201,169,106,.16);transform:translateY(-1px)}
.btn--quiet{background:var(--sand-soft);color:var(--ink)}
.btn--quiet:hover{background:var(--sand);color:var(--ink);transform:translateY(-1px)}

/* ---------- 7. 标签 ---------- */
.tag{
  display:inline-flex;align-items:center;gap:.4rem;
  padding:.24rem .78rem;border-radius:var(--r-pill);
  font-size:.72rem;font-weight:600;letter-spacing:.12em;
  line-height:1.6;white-space:nowrap;
}
.tag--sand{background:var(--sand-soft);color:var(--ink)}
.tag--clay{background:rgba(201,106,61,.16);color:var(--clay)}
.tag--sea{background:rgba(94,124,116,.16);color:var(--sea)}
.tag--ink{background:var(--ink);color:var(--sand-soft)}

/* ---------- 8. 面包屑 ---------- */
.breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:.5rem;
  font-size:.8rem;letter-spacing:.04em;color:var(--slate);
}
.breadcrumb li{display:flex;align-items:center;gap:.5rem}
.breadcrumb li + li::before{content:"/";color:var(--sand)}
.breadcrumb a{color:var(--slate);text-decoration:none;transition:color var(--dur) var(--ease)}
.breadcrumb a:hover{color:var(--clay)}
.breadcrumb [aria-current="page"]{color:var(--ink)}

/* ---------- 9. 图片容器基础规则 ---------- */
.media-frame{
  position:relative;overflow:hidden;
  border-radius:var(--r-lg);
  background:var(--paper-2);
  isolation:isolate;
}
.media-frame > picture,
.media-frame > img,
.media-frame > svg{
  display:block;width:100%;height:100%;object-fit:cover;
}
.media-frame--wide{aspect-ratio:16/9}
.media-frame--tall{aspect-ratio:4/5}
.media-frame--square{aspect-ratio:1/1}
.media-frame--flush{border-radius:0}
.section--ink .media-frame{background:var(--ink-2)}

/* ---------- 10. 焦点可见性 ---------- */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible{
  outline:2px solid var(--clay);
  outline-offset:3px;
  border-radius:4px;
}
.site-footer a:focus-visible,
.site-footer button:focus-visible{outline-color:var(--sand-soft)}

/* ==========================================================================
   页头
   ========================================================================== */
.site-header{
  position:sticky;top:0;z-index:90;
  color:var(--ink);
  background:rgba(247,243,234,.82);
  -webkit-backdrop-filter:blur(16px) saturate(1.05);
  backdrop-filter:blur(16px) saturate(1.05);
  border-bottom:1px solid var(--line-soft);
  transition:background-color .3s var(--ease),
             color .3s var(--ease),
             border-color .3s var(--ease);
}
.site-header[data-scrolled]{
  background:var(--ink);
  color:var(--paper);
  border-bottom-color:rgba(201,169,106,.30);
}

.skip-link{
  position:absolute;left:1rem;top:.45rem;z-index:120;
  transform:translateY(-180%);
  padding:.6rem 1.1rem;border-radius:var(--r-pill);
  background:var(--ink);color:var(--paper);
  font-size:.85rem;text-decoration:none;
  transition:transform .2s var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{transform:translateY(0);outline-color:var(--sand)}

.header-inner{
  width:var(--shell);margin-inline:auto;
  min-height:var(--header-h);
  display:flex;align-items:center;
  gap:clamp(.75rem,3vw,2.5rem);
}

/* 品牌 */
.brand{
  display:inline-flex;align-items:center;gap:.7rem;
  padding:.35rem 0;text-decoration:none;color:inherit;
  flex:0 0 auto;
}
.brand__mark{
  display:grid;place-items:center;
  width:34px;height:34px;flex:0 0 34px;
  border-radius:12px;
  background:var(--ink);color:var(--sand-soft);
  font-family:var(--font-title);font-size:.95rem;font-weight:600;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.brand__text{display:flex;flex-direction:column;line-height:1.15}
.brand__name{
  font-family:var(--font-title);font-size:1.05rem;
  font-weight:500;letter-spacing:.06em;
}
.brand__tag{
  font-size:.62rem;letter-spacing:.34em;
  color:var(--slate);text-transform:uppercase;
  transition:color var(--dur) var(--ease);
}
.site-header[data-scrolled] .brand__mark{background:var(--sand);color:var(--ink)}
.site-header[data-scrolled] .brand__tag{color:rgba(247,243,234,.62)}

/* 导航 */
.site-nav{
  margin-left:auto;
  display:flex;align-items:center;
  gap:clamp(.5rem,2vw,1.25rem);
}
.nav-list{
  display:flex;align-items:center;
  gap:clamp(.15rem,1vw,.75rem);
}
.nav-link{
  position:relative;
  display:inline-flex;align-items:baseline;gap:.35rem;
  padding:.5rem .6rem;border-radius:var(--r-pill);
  font-size:.9rem;text-decoration:none;color:inherit;
  transition:background-color var(--dur) var(--ease),
             color var(--dur) var(--ease),
             transform var(--dur) var(--ease);
}
.nav-link__num{
  font-family:var(--font-title);font-size:.66rem;font-weight:700;
  letter-spacing:.08em;color:var(--sand);
  font-variant-numeric:tabular-nums;
  transition:color var(--dur) var(--ease);
}
.nav-link:hover{background:rgba(201,169,106,.20);transform:translateY(-1px)}
.nav-link:hover .nav-link__num{color:var(--clay)}
.nav-link[aria-current="page"]{background:var(--sand-soft);color:var(--ink)}
.nav-link[aria-current="page"] .nav-link__num{color:var(--clay)}

.site-header[data-scrolled] .nav-link:hover{background:rgba(228,211,174,.14)}
.site-header[data-scrolled] .nav-link__num{color:var(--sand-soft)}
.site-header[data-scrolled] .nav-link:hover .nav-link__num{color:var(--sand)}
.site-header[data-scrolled] .nav-link[aria-current="page"]{background:var(--sand-soft);color:var(--ink)}
.site-header[data-scrolled] .nav-link[aria-current="page"] .nav-link__num{color:var(--clay)}

.nav-cta{flex:0 0 auto;padding:.58rem 1.15rem;font-size:.85rem}

/* 移动菜单按钮 */
.nav-toggle{
  display:none;align-items:center;gap:.5rem;
  margin-left:auto;padding:.5rem .85rem;
  border:1px solid var(--line);border-radius:var(--r-pill);
  font-size:.8rem;letter-spacing:.16em;color:inherit;
  transition:background-color var(--dur) var(--ease),
             border-color var(--dur) var(--ease);
}
.nav-toggle:hover{background:rgba(201,169,106,.20)}
.nav-toggle__bars{display:inline-flex;flex-direction:column;gap:4px;width:16px}
.nav-toggle__bars span{
  display:block;height:1.5px;width:100%;
  background:currentColor;border-radius:2px;
  transition:transform .22s var(--ease),opacity .22s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:first-child{transform:translateY(2.75px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:last-child{transform:translateY(-2.75px) rotate(-45deg)}
.site-header[data-scrolled] .nav-toggle{border-color:rgba(228,211,174,.34)}

/* 阅读进度 */
.read-progress{
  position:absolute;left:0;right:0;bottom:0;height:2px;
  transform:scaleX(0);transform-origin:0 50%;
  background:linear-gradient(90deg,var(--sand),var(--clay));
  pointer-events:none;
  transition:transform .12s linear;
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer{
  position:relative;overflow:hidden;
  background:var(--ink);color:var(--paper);
  padding-block:clamp(3rem,6vw,5.5rem) clamp(1.5rem,3vw,2.5rem);
}
.site-footer::before{
  content:"";position:absolute;inset:0 0 auto 0;height:1px;
  background:linear-gradient(90deg,transparent,rgba(201,169,106,.6),transparent);
}
.site-footer::after{
  content:"";position:absolute;pointer-events:none;
  width:520px;height:520px;right:-190px;top:-270px;border-radius:50%;
  background:radial-gradient(circle,rgba(201,169,106,.18),transparent 68%);
}
.footer-inner{position:relative;z-index:1;width:var(--shell);margin-inline:auto}

.footer-top{
  display:grid;
  grid-template-columns:minmax(0,1.6fr) repeat(3,minmax(0,1fr));
  gap:clamp(1.75rem,4vw,3rem);
}

.footer-brand{display:flex;flex-direction:column;gap:.55rem}
.footer-mark{
  display:grid;place-items:center;
  width:38px;height:38px;border-radius:13px;
  background:var(--sand);color:var(--ink);
  font-family:var(--font-title);font-size:1rem;font-weight:600;
}
.footer-name{
  font-family:var(--font-title);font-size:1.28rem;
  letter-spacing:.08em;color:var(--paper);
}
.footer-line{
  font-size:.94rem;line-height:1.7;
  color:rgba(247,243,234,.74);max-width:24ch;
}
.footer-note{
  font-size:.8rem;line-height:1.65;
  color:var(--on-ink-soft);max-width:30ch;
}

.footer-col{min-width:0}
.footer-col__head{
  display:flex;align-items:baseline;gap:.5rem;
  padding-bottom:.8rem;margin-bottom:.95rem;
  border-bottom:1px solid var(--on-ink-line);
  font-size:.72rem;letter-spacing:.24em;
  color:var(--sand);
}
.footer-col__num{
  font-family:var(--font-title);font-weight:700;
  font-size:1rem;letter-spacing:.04em;color:var(--sand-soft);
}
.footer-links li + li{margin-top:.55rem}
.footer-links a{
  display:inline-flex;align-items:center;gap:.5rem;
  font-size:.92rem;color:rgba(247,243,234,.76);
  transition:color var(--dur) var(--ease);
}
.footer-links a::before{
  content:"";display:block;width:0;height:1px;
  background:var(--sand);
  transition:width .22s var(--ease);
}
.footer-links a:hover{color:var(--paper)}
.footer-links a:hover::before{width:14px}

.footer-contact{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(200px,1fr));
  gap:1.25rem 2rem;
  margin-top:clamp(2.25rem,5vw,3.5rem);
  padding-top:clamp(1.5rem,3vw,2rem);
  border-top:1px solid var(--on-ink-line);
}
.footer-contact__item{min-width:0}
.footer-contact__label{
  margin-bottom:.3rem;
  font-size:.7rem;letter-spacing:.22em;
  color:rgba(201,169,106,.9);
}
.footer-contact__value{
  display:flex;flex-wrap:wrap;align-items:center;gap:.45rem;
  font-size:.95rem;color:rgba(247,243,234,.86);
  overflow-wrap:anywhere;
}

.copy-btn{
  display:inline-flex;align-items:center;justify-content:center;
  min-width:3.4rem;padding:.18rem .6rem;
  border:1px solid rgba(228,211,174,.32);border-radius:var(--r-pill);
  font-size:.7rem;letter-spacing:.08em;
  color:rgba(247,243,234,.82);
  transition:background-color var(--dur) var(--ease),
             border-color var(--dur) var(--ease),
             color var(--dur) var(--ease);
}
.copy-btn:hover{background:rgba(228,211,174,.14);color:var(--paper)}
.copy-btn[data-state="done"]{
  background:var(--sea);border-color:var(--sea);color:var(--white);
}

.footer-bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:.75rem 1.5rem;
  margin-top:clamp(1.75rem,4vw,2.75rem);
  padding-top:1.25rem;
  border-top:1px solid rgba(228,211,174,.14);
  font-size:.78rem;letter-spacing:.04em;
  color:var(--on-ink-soft);
}
.footer-copy,.footer-icp{margin:0}
.footer-legal{display:flex;flex-wrap:wrap;gap:.4rem 1.1rem}
.footer-legal a{color:inherit;text-decoration:none;transition:color var(--dur) var(--ease)}
.footer-legal a:hover{color:var(--sand-soft)}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1080px){
  .nav-link{padding:.5rem .45rem;font-size:.86rem}
  .nav-link__num{font-size:.62rem}
}

@media (max-width:900px){
  :root{--header-h:64px}

  .header-inner{gap:.75rem}
  .nav-toggle{display:inline-flex}

  .site-nav{
    position:absolute;top:100%;left:0;right:0;
    margin-left:0;
    display:flex;flex-direction:column;align-items:stretch;
    gap:.35rem;
    padding:1rem var(--gutter) 1.6rem;
    background:var(--paper);
    border-bottom:1px solid var(--line);
    box-shadow:0 30px 48px -36px rgba(15,34,51,.65);
    opacity:0;visibility:hidden;transform:translateY(-10px);
    transition:opacity .22s var(--ease),
               transform .22s var(--ease),
               visibility .22s linear;
  }
  .site-nav[data-open]{opacity:1;visibility:visible;transform:translateY(0)}

  .nav-list{flex-direction:column;align-items:stretch;width:100%;gap:0}
  .nav-list li + li{border-top:1px solid var(--line-soft)}
  .nav-link{width:100%;padding:.85rem .5rem;border-radius:var(--r-sm);font-size:1rem}
  .nav-link__num{font-size:.72rem}
  .nav-cta{margin-top:.85rem;width:100%}

  .site-header[data-scrolled] .site-nav{
    background:var(--ink-2);
    border-bottom-color:rgba(201,169,106,.28);
  }
  .site-header[data-scrolled] .nav-list li + li{border-top-color:rgba(228,211,174,.14)}

  .grid--split,.grid--aside,.grid--halves{grid-template-columns:1fr}

  .footer-top{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand{grid-column:1 / -1}
}

@media (max-width:560px){
  .footer-top{grid-template-columns:1fr}
  .footer-bottom{flex-direction:column;align-items:flex-start}
  .footer-legal{gap:.35rem .9rem}
  .type-lede{max-width:100%}
}

@media (max-width:380px){
  .brand__tag{letter-spacing:.24em}
  .nav-toggle__label{display:none}
}

/* ---------- 减弱动效 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms!important;
    animation-iteration-count:1!important;
    transition-duration:.001ms!important;
  }
  .read-progress{transition:none}
}