:root{
    --paper:#E7E7E5; --surface:#F0F0EE; --ink:#111111;
    --sub:#8C8C88; --mustard:#D8AA48; --hair:#CFCFCB;
    --mono:"Helvetica Neue",Helvetica,Inter,Arial,sans-serif;
    --play:Archivo,"Helvetica Neue",Helvetica,Arial,sans-serif;
    --jp:"Zen Kaku Gothic New","Hiragino Sans","Yu Gothic","Noto Sans JP",sans-serif;
  }
  *{margin:0;padding:0;box-sizing:border-box}
  html{scroll-behavior:smooth}
  body{font-family:var(--jp);font-weight:400;background:var(--paper);color:var(--ink);line-height:1.9;-webkit-font-smoothing:antialiased;overflow-x:hidden}
  a{color:inherit;text-decoration:none}
  img{display:block;max-width:100%}
  ::selection{background:var(--mustard);color:var(--ink)}
  :focus-visible{outline:3px solid var(--mustard);outline-offset:2px}
  html[data-lang="ja"] [lang="en"]{display:none}
  html[data-lang="en"] [lang="ja"]{display:none}

  header{position:sticky;top:0;z-index:100;background:var(--paper);display:flex;align-items:center;justify-content:space-between;gap:16px;padding:13px max(30px,calc((100% - 1160px)/2));border-bottom:2px solid var(--ink)}
  .lockup{display:flex;align-items:center;gap:12px;flex-shrink:0}
  .lockup .sym{width:34px}
  .lockup .wm{height:17px}
  nav.main{display:flex;gap:22px}
  nav.main a{font-family:var(--mono);font-size:11.5px;font-weight:600;letter-spacing:.14em;text-transform:uppercase;position:relative;white-space:nowrap}
  nav.main a::after{content:"";position:absolute;left:0;bottom:-4px;width:0;height:2px;background:var(--mustard);transition:width .25s}
  nav.main a:hover::after,nav.main a.current::after{width:100%}
  nav.main a.current{color:var(--ink)}
  .head-right{display:flex;align-items:center;gap:10px}
  .lang-toggle{display:flex;border:2px solid var(--ink);font-family:var(--mono);font-size:11px;font-weight:600;letter-spacing:.1em}
  .lang-toggle button{background:none;border:none;font:inherit;color:var(--ink);padding:5px 11px;cursor:pointer;transition:.18s}
  .lang-toggle button+button{border-left:2px solid var(--ink)}
  .lang-toggle button[aria-pressed="true"]{background:var(--ink);color:var(--mustard)}
  .contact-btn{font-family:var(--mono);font-size:12px;letter-spacing:.1em;text-transform:uppercase;border:2px solid var(--ink);padding:6px 14px;transition:.2s;white-space:nowrap}
  .contact-btn:hover,.contact-btn.current{background:var(--ink);color:var(--mustard)}
  @media(max-width:1000px){nav.main{display:none}header{padding:11px 18px}}

  .foot-min{padding:26px max(30px,calc((100% - 1160px)/2));border-top:2px solid var(--ink);display:flex;justify-content:space-between;flex-wrap:wrap;gap:14px;font-family:var(--mono);font-size:11px;color:var(--sub);letter-spacing:.06em;text-transform:uppercase}
  .foot-min a:hover{color:var(--ink)}

  .reveal{opacity:0;transform:translateY(18px);transition:opacity .6s ease,transform .6s ease}
  .reveal.in{opacity:1;transform:none}
  @media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}.reveal{opacity:1;transform:none}html{scroll-behavior:auto}}

  .eyebrow{font-family:var(--mono);font-size:12px;font-weight:600;letter-spacing:.14em;color:var(--sub);text-transform:uppercase}
  .eyebrow b{color:var(--ink);font-weight:600}
  .sec-head{display:flex;gap:14px;align-items:baseline;border-top:2px solid var(--ink);padding-top:18px;margin-bottom:40px;flex-wrap:wrap}
  .sec-head .idx{font-family:var(--mono);font-weight:600;font-size:12px;color:var(--mustard);letter-spacing:.14em}

  main.article{max-width:760px;margin:0 auto;padding:clamp(46px,6vw,88px) clamp(22px,5vw,40px) 40px}
  .docmeta{display:inline-block;border:2px solid var(--ink);padding:12px 16px;margin-bottom:34px;font-family:var(--mono);font-size:11px;font-weight:600;letter-spacing:.22em;line-height:1.9;text-transform:uppercase}
  .docmeta .k{color:var(--sub)}.docmeta .code{color:var(--mustard)}.docmeta .v{color:var(--ink)}
  .art-meta{display:flex;gap:14px;align-items:center;margin-bottom:16px}
  .art-date{font-family:var(--mono);font-size:13px;letter-spacing:.06em;color:var(--sub)}
  .art-cat{font-family:var(--mono);font-size:10.5px;letter-spacing:.08em;border:2px solid var(--ink);padding:2px 9px;text-transform:uppercase;font-weight:600}
  .a-title{font-weight:700;font-size:clamp(24px,3.6vw,34px);line-height:1.32;letter-spacing:.01em}
  .a-body{margin-top:30px}
  .a-body p{max-width:64ch;color:#242422;font-size:15px;margin:0 0 20px}
  .a-body p:last-child{margin-bottom:0}
  .a-body a.inl{text-decoration:underline;text-underline-offset:2px;text-decoration-color:var(--mustard)}
  .a-hr{height:2px;background:var(--ink);margin:44px 0 0}
  .art-nav{max-width:760px;margin:0 auto;padding:26px clamp(22px,5vw,40px) 0;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap}
  .art-nav a,.art-nav span{font-family:var(--mono);font-size:12px;font-weight:600;letter-spacing:.1em;text-transform:uppercase;display:inline-flex;gap:9px;align-items:center}
  .art-nav .disabled{color:var(--hair);cursor:default}
  .art-nav a:hover{color:var(--mustard)}
  .backall{display:inline-flex;gap:10px;align-items:center;font-family:var(--mono);font-weight:600;font-size:12px;letter-spacing:.1em;text-transform:uppercase}
  .backall .line{width:34px;height:2px;background:var(--ink);transition:width .3s}
  .backall:hover .line{width:56px}

  /* --- mobile nav --- */
  .nav-toggle{display:none;width:36px;height:30px;border:2px solid var(--ink);background:none;cursor:pointer;padding:0;position:relative;flex-shrink:0}
  .nav-toggle span{position:absolute;left:7px;right:7px;height:2px;background:var(--ink);transition:transform .25s,opacity .2s,top .25s}
  .nav-toggle span:nth-child(1){top:8px}.nav-toggle span:nth-child(2){top:13px}.nav-toggle span:nth-child(3){top:18px}
  .nav-toggle[aria-expanded="true"] span:nth-child(1){top:13px;transform:rotate(45deg)}
  .nav-toggle[aria-expanded="true"] span:nth-child(2){opacity:0}
  .nav-toggle[aria-expanded="true"] span:nth-child(3){top:13px;transform:rotate(-45deg)}
  .mobile-menu{display:none;position:absolute;top:100%;left:0;right:0;background:var(--paper);border-bottom:2px solid var(--ink);flex-direction:column;z-index:99}
  .mobile-menu.open{display:flex}
  .mobile-menu a{font-family:var(--mono);font-size:13px;font-weight:600;letter-spacing:.12em;text-transform:uppercase;padding:16px 22px;border-top:1px solid var(--hair)}
  .mobile-menu a:first-child{border-top:none}
  .mobile-menu a:hover,.mobile-menu a:active{background:var(--mustard)}
  @media(max-width:1000px){.nav-toggle{display:block}}
  @media(max-width:400px){header .wm{display:none}header{padding-left:14px;padding-right:14px;gap:10px}.head-right{gap:8px}.contact-btn{padding:6px 10px;font-size:11px}}

  /* --- 1160 gutter + sticky footer (2nd level) --- */
  body{min-height:100vh;display:flex;flex-direction:column}
  .foot-min{margin-top:auto}