/* ===========================================================
   开元棋盘会馆 · site.css
   数字会馆：门厅灯箱 / 悬挂指示牌 / 回廊纵深 / 蓝图细线
   =========================================================== */

:root{
  --hall:#0E2A22;
  --hall-2:#143B30;
  --hall-3:#081C16;
  --brass:#C08A3E;
  --lamp:#E3B566;
  --cinnabar:#B54836;
  --paper:#F5EFE3;
  --card:#FCF8F0;
  --guide:#D8D0C0;
  --moss:#6F8F7C;
  --ink:#1B1B18;

  --on-dark:#F1EADD;
  --on-dark-muted:#AEC2B6;
  --link:#12493A;

  --line-dark:rgba(216,208,192,.16);
  --line-strong:rgba(227,181,102,.35);
  --line-light:rgba(27,27,24,.16);

  --font-display:"Noto Serif SC","Source Han Serif SC","Songti SC","STSong",serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-index:"JetBrains Mono","IBM Plex Mono","SFMono-Regular",Menlo,Consolas,monospace;

  --shell:1200px;
  --header-h:118px;
  --shadow-brut:7px 7px 0 rgba(14,42,34,.16);
  --shadow-brass:5px 5px 0 rgba(192,138,62,.9);
}

/* ---------- reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(var(--header-h) + 20px)}
body{
  margin:0;
  padding-top:var(--header-h);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  color:var(--ink);
  background:var(--paper);
  -webkit-font-smoothing:antialiased;
}
img,svg,video{max-width:100%;height:auto;display:block}
h1,h2,h3,h4,p,figure,ul,ol,dl{margin:0}
ul,ol{padding:0}
button{font:inherit;color:inherit}
a{color:var(--link);text-decoration-thickness:1px;text-underline-offset:3px}
a:hover{color:var(--cinnabar)}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{
  outline:3px solid var(--brass);
  outline-offset:3px;
  border-radius:2px;
}
::selection{background:var(--lamp);color:var(--hall-3)}

/* ---------- 中文排版 ---------- */
h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:600;
  line-height:1.25;
  letter-spacing:-.008em;
  margin-bottom:.62em;
}
h1{font-size:clamp(34px,4.6vw,58px)}
h2{font-size:clamp(26px,3vw,36px)}
h3{font-size:clamp(20px,1.9vw,24px)}
h4{font-size:18px}
p{margin-bottom:1.05em}
p:last-child{margin-bottom:0}
.ky-lead{font-size:clamp(18px,1.6vw,20px);line-height:1.8;color:#2B332E;max-width:68ch}
.ky-prose{max-width:68ch}
.ky-prose ul,.ky-prose ol{padding-left:1.25em;margin-bottom:1.05em}
.ky-prose li{margin-bottom:.4em}

/* ---------- 容器 / 网格 ---------- */
.ky-shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:clamp(16px,4vw,40px);
}
.ky-main{display:block}
.ky-section{padding-block:clamp(40px,5vw,72px)}
.ky-section__head{max-width:70ch;margin-bottom:clamp(24px,3vw,40px)}
.ky-grid{display:grid;gap:clamp(16px,2.2vw,28px)}
.ky-grid--2{grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}
.ky-grid--3{grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}
.ky-rule{
  height:1px;
  border:0;
  background:linear-gradient(90deg,var(--brass) 0 56px,var(--line-light) 56px 100%);
  margin-block:clamp(24px,3vw,40px);
}

/* ---------- 索引铭牌 / 眉标 ---------- */
.ky-eyebrow{
  display:inline-block;
  font-family:var(--font-index);
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--brass);
  margin-bottom:14px;
}
.ky-index{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-index);
  font-size:12px;
  letter-spacing:.14em;
  color:var(--brass);
  border:1px solid var(--line-strong);
  padding:4px 10px;
  border-radius:2px;
  background:rgba(192,138,62,.08);
}
.ky-index::before{
  content:"";
  width:6px;height:6px;
  background:var(--cinnabar);
  display:block;
}

/* ---------- 按钮 ---------- */
.ky-btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:13px 24px;
  font-family:var(--font-body);
  font-size:15px;
  font-weight:600;
  line-height:1.2;
  text-decoration:none;
  border-radius:2px;
  border:2px solid var(--ink);
  background:var(--ink);
  color:var(--paper);
  box-shadow:var(--shadow-brass);
  transition:transform .18s ease,box-shadow .18s ease,background .18s ease,color .18s ease;
}
.ky-btn:hover,.ky-btn:focus-visible{
  color:var(--paper);
  background:#2A2A26;
  transform:translate(-2px,-2px);
  box-shadow:7px 7px 0 rgba(192,138,62,.95);
}
.ky-btn--gold{
  background:var(--brass);
  color:#1A1108;
  border-color:var(--ink);
  box-shadow:5px 5px 0 rgba(27,27,24,.85);
}
.ky-btn--gold:hover,.ky-btn--gold:focus-visible{background:var(--lamp);color:#1A1108}
.ky-btn--ghost{
  background:transparent;
  color:var(--lamp);
  border-color:var(--line-strong);
  box-shadow:none;
}
.ky-btn--ghost:hover,.ky-btn--ghost:focus-visible{
  background:rgba(227,181,102,.14);
  color:#FFF6E4;
  transform:translate(-1px,-1px);
  box-shadow:4px 4px 0 rgba(192,138,62,.45);
}

/* ---------- 面包屑 ---------- */
.ky-breadcrumb{margin-bottom:clamp(20px,2.4vw,32px)}
.ky-breadcrumb ol{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  list-style:none;
  font-family:var(--font-index);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--moss);
}
.ky-breadcrumb li{display:flex;align-items:center;gap:8px}
.ky-breadcrumb li:not(:first-child)::before{content:"›";color:var(--brass)}
.ky-breadcrumb a{color:var(--hall-2);text-decoration:none}
.ky-breadcrumb a:hover{color:var(--cinnabar);text-decoration:underline}
.ky-breadcrumb [aria-current="page"]{color:var(--ink)}

/* ---------- 面板 ---------- */
.ky-panel{
  background:var(--card);
  border:2px solid var(--ink);
  border-radius:2px;
  box-shadow:var(--shadow-brut);
  padding:clamp(20px,2.4vw,30px);
}
.ky-panel--dark{
  background:linear-gradient(160deg,var(--hall-2),var(--hall) 72%);
  border-color:rgba(192,138,62,.55);
  color:var(--on-dark);
  box-shadow:7px 7px 0 rgba(8,28,22,.4);
}
.ky-panel--dark h2,.ky-panel--dark h3{color:var(--paper)}
.ky-panel--dark a{color:var(--lamp)}

/* ---------- 影像容器 ---------- */
.ky-media{
  position:relative;
  overflow:hidden;
  border:2px solid var(--ink);
  border-radius:2px;
  background:
    repeating-conic-gradient(from 0deg, rgba(227,181,102,.10) 0% 25%, transparent 0% 50%) 0 0/26px 26px,
    var(--hall);
  aspect-ratio:16/10;
}
.ky-media img,.ky-media video{
  position:relative;
  z-index:1;
  width:100%;
  height:100%;
  object-fit:cover;
}
.ky-media--wide{aspect-ratio:21/9}
.ky-media--portrait{aspect-ratio:4/5}
.ky-media--blueprint::after{
  content:"";
  position:absolute;
  inset:0;
  z-index:2;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(227,181,102,.18) 1px,transparent 1px),
    linear-gradient(90deg,rgba(227,181,102,.18) 1px,transparent 1px);
  background-size:48px 48px;
  opacity:.55;
}
.ky-media__caption{
  position:absolute;
  left:0;right:0;bottom:0;
  z-index:3;
  padding:26px 16px 12px;
  font-family:var(--font-index);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--paper);
  background:linear-gradient(transparent,rgba(8,28,22,.86));
}

/* ---------- 标签页 ---------- */
.ky-tabs__list{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  list-style:none;
  border-bottom:2px solid var(--line-light);
  margin:0;
  padding:0;
}
.ky-tabs__tab{
  appearance:none;
  background:transparent;
  border:2px solid transparent;
  border-bottom:0;
  border-radius:2px 2px 0 0;
  padding:10px 16px;
  font-family:var(--font-index);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--hall-2);
  cursor:pointer;
  transition:background .2s ease,color .2s ease,border-color .2s ease;
}
.ky-tabs__tab:hover{background:rgba(192,138,62,.16)}
.ky-tabs__tab[aria-selected="true"]{
  background:var(--hall);
  border-color:var(--hall);
  color:var(--lamp);
  box-shadow:inset 0 4px 0 var(--brass);
}
.ky-tabs__panel{padding-top:clamp(18px,2.2vw,28px)}
.ky-tabs__panel[hidden]{display:none}

/* ---------- 手风琴 ---------- */
.ky-accordion{display:grid;gap:10px}
.ky-accordion__item{
  background:var(--card);
  border:2px solid var(--line-light);
  border-left:5px solid var(--brass);
  border-radius:2px;
}
.ky-accordion__trigger{
  width:100%;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  padding:16px 18px;
  background:transparent;
  border:0;
  text-align:left;
  font-size:16px;
  font-weight:600;
  color:var(--ink);
  cursor:pointer;
}
.ky-accordion__trigger::after{
  content:"+";
  font-family:var(--font-index);
  font-size:20px;
  line-height:1;
  color:var(--brass);
}
.ky-accordion__trigger[aria-expanded="true"]::after{content:"–"}
.ky-accordion__panel{
  padding:0 18px 18px;
  border-top:1px dashed var(--line-light);
  margin-top:0;
  padding-top:14px;
}
.ky-accordion__panel[hidden]{display:none}

/* ===========================================================
   头部
   =========================================================== */
.ky-skip{
  position:fixed;
  top:10px;
  left:10px;
  z-index:200;
  transform:translateY(-220%);
  padding:11px 18px;
  background:var(--lamp);
  color:#1A1108;
  border:2px solid var(--ink);
  border-radius:2px;
  font-family:var(--font-index);
  font-size:13px;
  letter-spacing:.06em;
  text-decoration:none;
  transition:transform .18s ease;
}
.ky-skip:focus{transform:translateY(0);color:#1A1108}

.ky-header{
  position:fixed;
  inset:0 0 auto 0;
  z-index:90;
  color:var(--on-dark);
  background:linear-gradient(180deg,rgba(8,28,22,.94) 0%,rgba(8,28,22,.72) 58%,rgba(8,28,22,0) 100%);
  transition:background .3s ease,box-shadow .3s ease;
}
.ky-header[data-stuck]{
  background:var(--hall);
  box-shadow:0 1px 0 rgba(192,138,62,.5),0 20px 40px -30px rgba(0,0,0,.9);
}

/* 活动指示牌 */
.ky-topbar{
  background:rgba(20,59,48,.72);
  border-bottom:1px solid rgba(192,138,62,.3);
}
.ky-topbar__inner{
  display:flex;
  align-items:center;
  gap:14px;
  min-height:44px;
}
.ky-topbar__plate{
  flex:none;
  font-family:var(--font-index);
  font-size:11px;
  font-weight:700;
  letter-spacing:.16em;
  color:#12210F;
  background:linear-gradient(180deg,var(--lamp),var(--brass));
  padding:4px 9px;
  border-radius:2px;
}
.ky-topbar__note{
  margin:0;
  font-size:13px;
  color:var(--on-dark-muted);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.ky-quick{
  display:flex;
  gap:6px;
  list-style:none;
  margin:0 0 0 auto;
  padding:0;
}
.ky-quick__link{
  display:inline-block;
  padding:4px 11px;
  font-family:var(--font-index);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--lamp);
  text-decoration:none;
  border:1px solid rgba(227,181,102,.36);
  border-radius:2px;
  transition:background .2s ease,color .2s ease;
}
.ky-quick__link:hover,.ky-quick__link:focus-visible{
  background:rgba(227,181,102,.18);
  color:#FFF6E4;
}

/* 门厅主条 */
.ky-bar{background:transparent}
.ky-bar__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:24px;
  min-height:74px;
}
.ky-brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  color:inherit;
  text-decoration:none;
  flex:none;
}
.ky-brand:hover{color:inherit}
.ky-brand__mark{
  width:34px;
  height:34px;
  flex:none;
  display:grid;
  grid-template-columns:1fr 1fr;
  grid-template-rows:1fr 1fr;
  border:1px solid var(--brass);
  background:var(--hall-3);
  overflow:hidden;
}
.ky-brand__mark i{display:block;background:transparent}
.ky-brand__mark i:nth-child(1),
.ky-brand__mark i:nth-child(4){
  background:linear-gradient(160deg,var(--lamp),var(--brass));
}
.ky-brand__text{display:flex;flex-direction:column;line-height:1.15}
.ky-brand__name{
  font-family:var(--font-display);
  font-weight:700;
  font-size:21px;
  letter-spacing:.04em;
  color:var(--paper);
}
.ky-brand__tag{
  margin-top:3px;
  font-family:var(--font-index);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--lamp);
  opacity:.88;
}

/* 主导航 */
.ky-nav__list{
  display:flex;
  align-items:center;
  gap:2px;
  list-style:none;
  margin:0;
  padding:0;
}
.ky-nav__link{
  position:relative;
  display:block;
  padding:10px 12px;
  font-size:15px;
  color:var(--on-dark);
  text-decoration:none;
  border:1px solid transparent;
  border-radius:2px;
  transition:color .2s ease,background .2s ease,border-color .2s ease;
}
.ky-nav__link::after{
  content:"";
  position:absolute;
  left:12px;right:12px;bottom:5px;
  height:1px;
  background:var(--brass);
  transform:scaleX(0);
  transform-origin:left;
  transition:transform .24s ease;
}
.ky-nav__link:hover,.ky-nav__link:focus-visible{color:var(--lamp)}
.ky-nav__link:hover::after,.ky-nav__link:focus-visible::after{transform:scaleX(1)}
.ky-nav__link[aria-current="page"]{
  color:var(--lamp);
  border-color:rgba(192,138,62,.45);
  background:rgba(192,138,62,.13);
}
.ky-nav__link[aria-current="page"]::after{
  transform:scaleX(1);
  background:var(--cinnabar);
}

/* 移动导航按钮 */
.ky-nav-toggle{
  display:none;
  align-items:center;
  gap:9px;
  padding:9px 13px;
  background:transparent;
  border:1px solid rgba(192,138,62,.55);
  border-radius:2px;
  color:var(--lamp);
  font-family:var(--font-index);
  font-size:11px;
  letter-spacing:.18em;
  cursor:pointer;
  transition:background .2s ease;
}
.ky-nav-toggle:hover{background:rgba(192,138,62,.16)}
.ky-nav-toggle__bars{display:grid;gap:4px;width:16px}
.ky-nav-toggle__bars i{
  display:block;
  height:1.5px;
  background:currentColor;
  transition:transform .24s ease,opacity .2s ease;
}
.ky-nav-toggle__label{line-height:1}
.ky-nav-toggle[aria-expanded="true"] .ky-nav-toggle__bars i:nth-child(1){transform:translateY(5.5px) rotate(45deg)}
.ky-nav-toggle[aria-expanded="true"] .ky-nav-toggle__bars i:nth-child(2){opacity:0}
.ky-nav-toggle[aria-expanded="true"] .ky-nav-toggle__bars i:nth-child(3){transform:translateY(-5.5px) rotate(-45deg)}

/* ===========================================================
   页脚
   =========================================================== */
.ky-footer{
  position:relative;
  margin-top:clamp(48px,6vw,96px);
  padding:clamp(44px,5vw,72px) 0 26px;
  background:linear-gradient(180deg,var(--hall) 0%,var(--hall-3) 100%);
  color:var(--on-dark);
  border-top:3px solid var(--brass);
  overflow:hidden;
}
.ky-footer::before{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(216,208,192,.07) 1px,transparent 1px),
    linear-gradient(90deg,rgba(216,208,192,.07) 1px,transparent 1px);
  background-size:64px 64px;
  mask-image:linear-gradient(180deg,rgba(0,0,0,.9),transparent 88%);
  -webkit-mask-image:linear-gradient(180deg,rgba(0,0,0,.9),transparent 88%);
}
.ky-footer > .ky-shell{position:relative;z-index:1}
.ky-footer__grid{
  display:grid;
  grid-template-columns:1.5fr 1fr 1fr 1.35fr;
  gap:clamp(24px,3vw,40px);
}
.ky-footer__col{min-width:0}
.ky-footer__brandline{
  font-family:var(--font-display);
  font-size:clamp(21px,2.3vw,28px);
  line-height:1.42;
  letter-spacing:.01em;
  color:var(--paper);
  margin:0 0 14px;
}
.ky-footer__title{
  font-family:var(--font-index);
  font-size:11px;
  font-weight:700;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--brass);
  margin:0 0 14px;
}
.ky-footer__links{
  list-style:none;
  margin:0 0 0;
  padding:0;
  display:grid;
  gap:9px;
}
.ky-footer__links a{
  color:var(--on-dark);
  font-size:15px;
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s ease,border-color .2s ease;
}
.ky-footer__links a:hover,.ky-footer__links a:focus-visible{
  color:var(--lamp);
  border-bottom-color:rgba(227,181,102,.6);
}
.ky-footer__links a[aria-current="page"]{color:var(--lamp)}
.ky-footer__note{
  margin:14px 0 0;
  font-size:13px;
  line-height:1.9;
  color:var(--on-dark-muted);
}
.ky-footer__base{
  margin-top:clamp(28px,3.4vw,46px);
  padding-top:18px;
  border-top:1px solid rgba(216,208,192,.2);
  display:flex;
  flex-wrap:wrap;
  justify-content:space-between;
  gap:8px 28px;
  font-family:var(--font-index);
  font-size:12px;
  letter-spacing:.04em;
  color:var(--on-dark-muted);
}
.ky-footer__legal{margin:0}

/* ===========================================================
   响应式
   =========================================================== */
@media (max-width:1023px){
  :root{--header-h:100px}

  .ky-topbar__inner{min-height:38px}
  .ky-bar__inner{min-height:62px}
  .ky-brand__name{font-size:19px}

  .ky-nav-toggle{display:inline-flex}

  .ky-nav{
    position:fixed;
    left:0;right:0;
    top:var(--header-h);
    max-height:calc(100vh - var(--header-h));
    overflow-y:auto;
    background:var(--hall-3);
    border-top:1px solid rgba(192,138,62,.32);
    box-shadow:0 30px 50px -30px rgba(0,0,0,.9);
    padding:6px 0 22px;
    opacity:0;
    visibility:hidden;
    transform:translateY(-10px);
    transition:opacity .22s ease,transform .22s ease,visibility .22s ease;
  }
  .ky-header[data-open] .ky-nav{
    opacity:1;
    visibility:visible;
    transform:translateY(0);
  }
  .ky-nav__list{
    flex-direction:column;
    align-items:stretch;
    gap:0;
    padding:6px clamp(16px,4vw,32px);
  }
  .ky-nav__link{
    padding:15px 4px;
    font-size:17px;
    border-bottom:1px solid var(--line-dark);
    border-radius:0;
  }
  .ky-nav__link::after{display:none}
  .ky-nav__link[aria-current="page"]{
    background:rgba(192,138,62,.16);
    border-left:3px solid var(--cinnabar);
    padding-left:12px;
  }
}

@media (max-width:860px){
  .ky-topbar__note{display:none}
  .ky-footer__grid{grid-template-columns:1fr 1fr}
  .ky-footer__col--brand{grid-column:1 / -1}
}

@media (max-width:640px){
  :root{--header-h:90px}
  body{font-size:16px}
  .ky-topbar__inner{min-height:34px;gap:8px}
  .ky-topbar__plate{font-size:10px;padding:3px 7px;letter-spacing:.12em}
  .ky-quick__link{font-size:11px;padding:3px 8px}
  .ky-bar__inner{min-height:56px;gap:12px}
  .ky-brand__mark{width:28px;height:28px}
  .ky-brand__name{font-size:17px}
  .ky-brand__tag{font-size:10px;letter-spacing:.1em}
  .ky-footer__grid{grid-template-columns:1fr}
  .ky-footer__base{flex-direction:column}
  .ky-btn{width:100%;justify-content:center}
}

/* ===========================================================
   可访问性
   =========================================================== */
@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;
  }
}