/* ===== EMS — fresh design v1 ===== */
:root{
  --bg:#F5F2EC;          /* warm paper */
  --surface:#FFFFFF;
  --surface-2:#FBF9F4;
  --ink:#222A2B;         /* near-black, slightly green */
  --muted:#6A726E;
  --accent:#2E7D6B;      /* sage teal */
  --accent-dark:#225e50;
  --accent-soft:#E7EFEA;
  --line:#E4DFD4;
  --shadow:0 1px 2px rgba(34,42,43,.04), 0 8px 28px -12px rgba(34,42,43,.18);
  --radius:18px;
  --img-radius:2px;
  --maxw:1120px;
  --read:46rem;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:"Inter",system-ui,-apple-system,sans-serif;
  font-size:17px;line-height:1.7;-webkit-font-smoothing:antialiased;
  min-height:100vh;display:flex;flex-direction:column;
}
h1,h2,h3,h4{font-family:"Fraunces",Georgia,serif;font-weight:500;line-height:1.15;color:var(--ink)}
a{color:var(--accent-dark);text-decoration:none}
p{margin:0 0 1rem}
strong{font-weight:600;color:var(--ink)}

/* Keyboard focus: a consistent ring on all interactive elements */
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}

/* Skip link: visually hidden until focused, then pinned top-left */
.skip-link{position:fixed;top:-100px;left:1rem;z-index:100;background:var(--accent);color:#fff;font-weight:600;font-size:.9rem;padding:.6rem 1rem;border-radius:999px;transition:top .15s ease}
.skip-link:focus{top:1rem}

main{width:100%;max-width:var(--maxw);margin:0 auto;flex:1 0 auto;padding:clamp(1rem,3vw,2rem) clamp(1rem,4vw,2.5rem) 4rem}

/* ---- hero ---- */
.hero{padding:clamp(3rem,8vw,6rem) 0 clamp(2rem,5vw,3.5rem);max-width:42rem}
.hero.compact{padding:clamp(2.5rem,6vw,4rem) 0 1rem}
.hero h1{font-size:clamp(2.6rem,7vw,4.4rem);margin:0 0 1.2rem;letter-spacing:-.5px}
.lede{font-size:1.18rem;color:var(--muted);margin:0 0 1.8rem}
.hero-cta{margin:1.8rem 0 0}
.btn{display:inline-block;background:var(--accent);color:#fff;font-weight:600;font-size:1rem;padding:.8rem 1.5rem;border-radius:999px;transition:transform .15s ease,background .15s ease}
.btn:hover{background:var(--accent-dark);transform:translateY(-1px)}
.home-hero{max-width:none;display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,1fr);gap:clamp(1.5rem,5vw,4rem);align-items:center}
.home-hero-text{max-width:34rem}
.home-hero-img{aspect-ratio:1/1;border-radius:var(--img-radius);background-size:cover;background-position:center;background-color:var(--accent-soft);position:relative;overflow:hidden}
/* Normal-map relief lighting: a WebGL canvas renders the cover lit by a
   cursor-following light. The base background-image is the no-WebGL fallback. */
.relief-canvas{position:absolute;inset:0;width:100%;height:100%;display:block;opacity:0;transition:opacity .35s ease}
.relief-canvas.ready{opacity:1}
/* Touch drives the light instead of scrolling the page while on the image. */
.relief{touch-action:none}

.section-title{font-size:clamp(1.5rem,3vw,2rem);margin:0 0 .4rem}
.muted{color:var(--muted)}

/* ---- home grid ---- */
.grid-wrap{padding-top:1rem}
.grid{
  display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));
  gap:1.1rem;margin-top:1.6rem;
}
.card{
  display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--line);
  border-radius:calc(var(--radius) / 2);overflow:hidden;transition:transform .18s ease,border-color .18s ease;
}
.card:hover{transform:translateY(-4px);border-color:var(--accent)}
.card-img{display:block;aspect-ratio:3/2;background-size:cover;background-position:center;background-color:var(--accent-soft)}
.card-body{padding:1.05rem 1.15rem 1.25rem;display:flex;flex-direction:column;gap:.35rem}
.card-name{font-family:"Fraunces",serif;font-size:1.18rem;font-weight:600;color:var(--ink);line-height:1.2}
.card-teaser{font-size:.92rem;color:var(--muted);line-height:1.5}

/* ---- schema page ---- */
.schema{max-width:var(--maxw)}
.back{display:inline-block;color:var(--muted);font-weight:500;font-size:.92rem;margin:1.5rem 0 0;background:var(--surface);border:1px solid var(--line);padding:.4rem .9rem;border-radius:999px;transition:color .15s ease,border-color .15s ease,background .15s ease}
.back:hover{color:var(--ink);border-color:var(--accent);background:var(--surface-2)}
.schema-hero{
  display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.1fr);gap:clamp(1.5rem,4vw,3rem);
  align-items:start;padding:1.5rem 0 clamp(2rem,5vw,3.5rem);
  border-bottom:1px dashed var(--line);
}
.schema-hero-img{
  aspect-ratio:1/1;border-radius:var(--img-radius);background-size:contain;background-repeat:no-repeat;background-position:center;
  background-color:var(--accent-soft);position:relative;
}
.schema-hero h1{font-size:clamp(2.2rem,5vw,3.4rem);margin:.3rem 0 1rem;letter-spacing:-.5px;color:var(--accent)}
.schema-hero .lede{font-size:1.1rem}

/* ---- schema explorer: sidebar + content ---- */
.explorer{display:grid;grid-template-columns:minmax(190px,236px) minmax(0,1fr);gap:clamp(1.5rem,4vw,3.2rem);align-items:start;scroll-margin-top:1.5rem;margin-top:clamp(2rem,5vw,3rem)}
.cat-nav{display:flex;flex-direction:column;gap:.1rem;position:sticky;top:1.5rem}
.cat-link{
  appearance:none;border:0;background:none;cursor:pointer;width:100%;text-align:left;
  font-family:"Fraunces",serif;font-size:1.02rem;font-weight:500;line-height:1.3;color:var(--muted);
  padding:.6rem .85rem;border-radius:10px;border-left:2px solid transparent;
  transition:color .15s ease,background .15s ease,border-color .15s ease;
}
.cat-link:hover{color:var(--ink);background:var(--surface-2)}
.cat-link.active{color:var(--accent-dark);background:var(--accent-soft);font-weight:600}
.cat-panels{max-width:var(--read);min-width:0}
.cat-panel{display:none}
.cat-panel.active{display:block;animation:catfade .25s ease}
@keyframes catfade{from{opacity:0;transform:translateY(5px)}to{opacity:1;transform:none}}
.cat-panel>h3{font-size:clamp(1.5rem,3vw,2rem);margin:0 0 1.1rem}
.cat-panel h4{font-family:"Inter",sans-serif;font-size:.8rem;letter-spacing:.1em;text-transform:uppercase;color:var(--accent);margin:1.8rem 0 .7rem}
.cat-panel p{margin:0 0 1rem}
.cat-panel ul{list-style:none;margin:0 0 1rem;padding:0;display:flex;flex-direction:column;gap:.7rem}
.cat-panel li{padding-left:1.1rem;position:relative}
.cat-panel li::before{content:"";position:absolute;left:0;top:.62em;width:6px;height:6px;border-radius:50%;background:var(--accent);opacity:.55}
.ask-ai{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem;margin:0 0 1.6rem}
.ask-ai-label{font-size:.85rem;color:var(--muted);margin-right:.15rem}
.ask-btn{font-size:.85rem;font-weight:600;color:var(--accent-dark);background:var(--surface);border:1px solid var(--line);padding:.35rem .8rem;border-radius:999px;transition:border-color .15s ease,background .15s ease}
.ask-btn:hover{border-color:var(--accent);background:var(--accent-soft)}

/* ---- prose (about) ---- */
.prose{max-width:var(--read)}
.prose .section-title{margin-top:2.6rem}
.prose ul{list-style:none;padding:0;display:flex;flex-direction:column;gap:.6rem}
.prose li{padding-left:1.1rem;position:relative}
.prose li::before{content:"";position:absolute;left:0;top:.62em;width:6px;height:6px;border-radius:50%;background:var(--accent);opacity:.55}
.prose h4{font-size:1.05rem;margin:1.4rem 0 .5rem}

/* ---- about modal ---- */
.modal{max-width:660px;width:calc(100% - 2rem);max-height:85vh;border:none;border-radius:var(--radius);padding:0;background:var(--bg);color:var(--ink);box-shadow:var(--shadow);overflow:hidden}
.modal::backdrop{background:rgba(34,42,43,.5)}
.modal-body{padding:clamp(1.5rem,4vw,2.6rem);overflow-y:auto;max-height:85vh}
.modal-body .hero.compact{padding:0 0 .5rem}
.modal-body .section-title:first-of-type{margin-top:1.4rem}
.modal-close{position:absolute;top:.7rem;right:.9rem;z-index:2;width:2rem;height:2rem;display:flex;align-items:center;justify-content:center;font-size:1.5rem;line-height:1;cursor:pointer;color:var(--muted);background:var(--surface);border:1px solid var(--line);border-radius:999px}
.modal-close:hover{color:var(--ink);border-color:var(--accent)}

/* ---- footer ---- */
.site-footer{border-top:1px solid var(--line);margin-top:3rem;padding:2.5rem clamp(1rem,4vw,2.5rem);max-width:var(--maxw);margin-left:auto;margin-right:auto;width:100%;box-sizing:border-box;flex-shrink:0;color:var(--muted);font-size:.9rem}
.footer-nav{display:flex;gap:1.5rem;margin-bottom:1.4rem}
.footer-nav a{font-family:"Fraunces",serif;font-size:1rem;font-weight:600;color:var(--ink)}
.footer-nav a:hover{color:var(--accent-dark)}
.site-footer .disclaimer{max-width:46rem;margin-top:.5rem}

@media(max-width:720px){
  .home-hero{grid-template-columns:1fr}
  .home-hero-img{order:-1;aspect-ratio:16/10}
  .schema-hero{grid-template-columns:1fr}
  .schema-hero-img{aspect-ratio:1/1}
  .explorer{grid-template-columns:1fr}
  .cat-nav{flex-direction:row;overflow-x:auto;position:static;gap:.4rem;padding-bottom:.6rem;margin-bottom:1.4rem;border-bottom:1px solid var(--line);-webkit-overflow-scrolling:touch}
  .cat-link{white-space:nowrap;border-left:0;border-radius:999px;background:var(--surface);border:1px solid var(--line);padding:.45rem .9rem;font-size:.95rem}
  .cat-link.active{background:var(--accent-soft);border-color:var(--accent)}
}

/* ---- language toggle (fixed top-right on every page) ---- */
.lang-toggle{position:fixed;top:1rem;right:1rem;z-index:50;display:flex;gap:.1rem;background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:saturate(1.4) blur(8px);border:1px solid var(--line);border-radius:999px;padding:.2rem}
.lang-toggle a{font-family:"Inter",sans-serif;font-size:.82rem;font-weight:600;color:var(--muted);padding:.32rem .66rem;border-radius:999px;line-height:1}
.lang-toggle a.on{background:var(--accent);color:#fff}
.lang-toggle a:not(.on):hover{color:var(--ink)}

/* ---- Persian / RTL ---- */
html[lang="fa"] body, html[lang="fa"] h1, html[lang="fa"] h2, html[lang="fa"] h3, html[lang="fa"] h4,
html[lang="fa"] .cat-link, html[lang="fa"] .card-name, html[lang="fa"] .footer-nav a,
html[lang="fa"] .back, html[lang="fa"] .pager strong, html[lang="fa"] .brand{font-family:"Vazirmatn",Tahoma,sans-serif}
[dir="rtl"] .cat-link{text-align:right;border-left:0;border-right:2px solid transparent}
[dir="rtl"] .cat-panel ul, [dir="rtl"] .prose ul{padding-right:0}
[dir="rtl"] .cat-panel li, [dir="rtl"] .prose li{padding-left:0;padding-right:1.1rem}
[dir="rtl"] .cat-panel li::before, [dir="rtl"] .prose li::before{left:auto;right:0}

/* ---- Traditional Chinese (Latin stays in Inter/Fraunces; CJK falls to Noto Serif TC) ---- */
html[lang="zh-TW"] body{font-family:"Inter","Noto Serif TC",system-ui,-apple-system,sans-serif}
html[lang="zh-TW"] h1, html[lang="zh-TW"] h2, html[lang="zh-TW"] h3, html[lang="zh-TW"] h4,
html[lang="zh-TW"] .cat-link, html[lang="zh-TW"] .card-name, html[lang="zh-TW"] .footer-nav a{font-family:"Fraunces","Noto Serif TC",Georgia,serif}

/* ---- reduced motion: honor the user's OS preference ---- */
@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}
  .cat-panel.active{animation:none}
}