:root{
    --bg:#fff; --surface:#fff; --ink:#000; --muted:#5f5f5f; --line:#e2e2e2; --soft:#f3f3f3;
    --sans:'Be Vietnam Pro',system-ui,-apple-system,'Segoe UI',sans-serif;
    --wiki:'Linux Libertine','Georgia','Times',serif; /* Wikipedia heading font */
    --ease:cubic-bezier(.2,.7,.2,1); --nav-h:61px;
}
:root[data-theme="dark"]{--bg:#000; --surface:#0b0b0b; --ink:#fff; --muted:#9b9b9b; --line:#252525; --soft:#151515}
*{box-sizing:border-box;margin:0}
html{scroll-behavior:smooth;color-scheme:light}
:root[data-theme="dark"]{color-scheme:dark}
body{background:var(--bg);color:var(--ink);font-family:var(--sans);line-height:1.6;transition:background .35s,color .35s;-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}
img{max-width:100%}
::selection{background:var(--ink);color:var(--bg)}
a{color:inherit}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
:focus-visible{outline:2px solid var(--ink);outline-offset:3px;border-radius:6px}
h1,h2,h3{font-family:var(--wiki);font-weight:400}
.wrap{max-width:1120px;margin:0 auto;padding:0 max(24px,env(safe-area-inset-right)) 0 max(24px,env(safe-area-inset-left))}

/* Navbar */
.nav{position:sticky;top:0;z-index:50;background:color-mix(in srgb,var(--bg) 85%,transparent);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.nav .wrap{display:flex;align-items:center;gap:16px;min-height:60px}
.brand{font-family:var(--wiki);font-size:26px;letter-spacing:-.01em;text-decoration:none}
.sbox{position:relative}
.nav-search{flex:1;max-width:400px;margin-left:auto}
.nav-search input{width:100%;height:38px;border-radius:999px;border:1px solid var(--line);background:var(--surface);color:var(--ink);padding:0 16px;font:inherit;font-size:14px;transition:border-color .2s}
.nav-search input:focus{outline:none;border-color:var(--ink)}
.nav-tools{display:flex;gap:6px;align-items:center}
.icon-btn{width:38px;height:38px;border-radius:50%;display:grid;place-items:center;border:1px solid var(--line);background:var(--surface);transition:transform .25s var(--ease),border-color .2s}
.icon-btn:hover{border-color:var(--ink)}
.icon-btn:active{transform:scale(.92)}
#themeBtn svg{width:18px;height:18px;transition:transform .5s var(--ease)}
#themeBtn:hover svg{transform:rotate(25deg)}
.sun{display:none}
:root[data-theme="dark"] .sun{display:block}
:root[data-theme="dark"] .moon{display:none}

/* Article suggestions */
.suggest{position:absolute;top:calc(100% + 8px);left:0;right:0;z-index:70;background:var(--surface);border:1px solid var(--line);border-radius:16px;overflow-y:auto;max-height:min(60vh,420px);display:none;text-align:left;box-shadow:0 16px 48px rgba(0,0,0,.18)}
.suggest.on{display:block}
.sg-h{padding:10px 16px 4px;font-size:12px;color:var(--muted)}
.suggest button{display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:9px 16px;font-size:14px}
.suggest button:hover,.suggest button.sel{background:var(--soft)}
.th{width:38px;height:38px;border-radius:8px;background:var(--soft) center/cover no-repeat;flex:none;display:grid;place-items:center;font-family:var(--wiki);font-size:18px;color:var(--muted);border:1px solid var(--line)}
.th{overflow:hidden}
.th img{width:100%;height:100%;object-fit:cover;object-position:50% 20%;display:block}
.tx{min-width:0}
.tx b{display:block;font-weight:400;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.tx mark{background:none;color:var(--ink);font-weight:600}
.tx small{display:block;color:var(--muted);font-size:12px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

/* Hero */
.hero{position:relative;min-height:min(calc(100svh - var(--nav-h)),900px);display:grid;place-items:center;border-bottom:1px solid var(--line)}
#graph{position:absolute;inset:0;width:100%;height:100%}
.hero-in{position:relative;z-index:2;width:100%;text-align:center;padding:40px 24px;pointer-events:none}
.hero-in>*{pointer-events:auto}
.hero h1{font-size:clamp(56px,13vw,160px);letter-spacing:-.025em;line-height:1;display:flex;justify-content:center;overflow:hidden;padding-bottom:.1em}
.hero h1 span{display:inline-block;transform:translateY(110%);animation:rise 1s var(--ease) forwards;animation-delay:calc(var(--i)*60ms + 150ms)}
@keyframes rise{to{transform:none}}
.tag{margin-top:18px;font-family:var(--wiki);font-size:clamp(20px,2.6vw,28px);color:var(--muted);min-height:1.6em}
.tag b{color:var(--ink);font-weight:400;font-style:italic;display:inline-block;animation:swap .6s var(--ease)}
@keyframes swap{from{opacity:0;filter:blur(8px);transform:translateY(8px)}to{opacity:1;filter:none;transform:none}}
.hero-box{margin:32px auto 0;max-width:540px}
.hero-search{display:flex;gap:8px;background:var(--surface);border:1px solid var(--line);border-radius:999px;padding:6px;transition:border-color .2s,box-shadow .3s}
.hero-search:focus-within{border-color:var(--ink);box-shadow:0 0 0 4px color-mix(in srgb,var(--ink) 12%,transparent)}
.hero-search input{flex:1;border:0;background:none;color:var(--ink);font:inherit;padding:0 18px;min-width:0}
.hero-search input:focus{outline:none}
.btn{height:44px;padding:0 22px;border-radius:999px;background:var(--ink);color:var(--bg);font-weight:500;transition:transform .25s var(--ease),opacity .2s}
.btn:hover{opacity:.85}.btn:active{transform:scale(.96)}
.btn.ghost{background:none;color:var(--ink);border:1px solid var(--line)}
.btn.ghost:hover{border-color:var(--ink);opacity:1}
.count{margin-top:22px;font-family:var(--wiki);font-size:18px;color:var(--muted)}
.count b{font-weight:400;color:var(--ink);font-size:1.25em;font-variant-numeric:tabular-nums}
.scroll-hint{position:absolute;bottom:22px;left:50%;width:1px;height:44px;background:linear-gradient(var(--muted),transparent);animation:drip 2s ease-in-out infinite}
@keyframes drip{0%,100%{transform:scaleY(.3);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}}

/* Explore */
section.explore{padding:72px 0 96px}
.head{display:flex;align-items:end;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-bottom:24px;padding-bottom:12px;border-bottom:1px solid var(--line)}
.head h2{font-size:clamp(30px,4.4vw,44px);line-height:1.15}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:32px}
.chip{padding:8px 16px;border-radius:999px;border:1px solid var(--line);background:var(--surface);font-size:14px;transition:all .2s}
.chip:hover{border-color:var(--ink)}
.chip[aria-pressed="true"]{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,230px),1fr));gap:20px}
.wide{grid-column:1/-1}
.card{display:flex;flex-direction:column;text-decoration:none;background:var(--surface);border:1px solid var(--line);border-radius:14px;overflow:hidden;transition:transform .35s var(--ease),border-color .25s}
@media (hover:hover){.card:hover{transform:translateY(-4px);border-color:var(--ink)}}
.card .img{aspect-ratio:16/10;background:var(--soft);border-bottom:1px solid var(--line);display:grid;place-items:center;font-family:var(--wiki);font-size:48px;color:var(--muted);overflow:hidden}
.card .img img{width:100%;height:100%;object-fit:cover;object-position:50% 20%;display:block}
.card .txt{padding:16px 18px 20px}
.card h3{font-size:22px;line-height:1.25;margin-bottom:6px}
.card p{font-size:14px;color:var(--muted);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.skel{height:300px;border-radius:14px;background:linear-gradient(100deg,var(--soft) 30%,var(--line) 50%,var(--soft) 70%) 0 0/300% 100%;animation:sh 1.3s linear infinite}
@keyframes sh{to{background-position:-300% 0}}
.msg{padding:48px 0;color:var(--muted);text-align:center}
.note{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;padding:12px 16px;border:1px dashed var(--muted);border-radius:12px;font-size:14px;color:var(--muted)}
.note button{text-decoration:underline;color:var(--ink)}

/* Article */
.progress{position:fixed;top:0;left:0;height:2px;background:var(--ink);width:0;z-index:80}
.art{padding:48px 0 96px;display:grid;grid-template-columns:minmax(0,1fr) 220px;gap:56px;align-items:start}
.back{display:inline-block;margin-bottom:28px;color:var(--muted);font-size:14px;text-decoration:none}
.back:hover{color:var(--ink)}
.art h1{font-size:clamp(36px,6vw,58px);line-height:1.12;padding-bottom:.2em;border-bottom:1px solid var(--line)}
.art .desc{color:var(--muted);margin:14px 0 28px;font-size:16px}
.art figure{margin:0 0 32px}
.art figure img{display:block;width:auto;max-width:100%;max-height:480px;object-fit:contain;border-radius:12px;border:1px solid var(--line)}
.body{font-size:16px;line-height:1.8;max-width:70ch}
.body p{margin:0 0 1.1em}
.body h2{font-size:32px;line-height:1.25;margin:1.8em 0 .6em;padding-bottom:.15em;border-bottom:1px solid var(--line);scroll-margin-top:80px}
.body h3,.body h4{font-family:var(--sans);font-size:17px;font-weight:600;margin:1.5em 0 .5em}
.body ul,.body ol{margin:0 0 1.1em 1.3em}
.body dl{margin:0 0 1.1em}
.body dd{margin-left:1.2em}
.body sup{font-size:.7em}
.lead{display:grid;grid-template-columns:300px minmax(0,1fr);gap:32px;align-items:start;margin:0 0 32px}
.lead.noimg{grid-template-columns:1fr}
.lead figure{margin:0;border-radius:12px;overflow:hidden;border:1px solid var(--line);background:var(--soft)}
.lead figure img{display:block;width:100%;height:auto;max-height:520px;object-fit:contain;border:0;border-radius:0}
.summary{font-size:17px;line-height:1.75;margin:0 0 20px}
.facts{display:grid;border-top:1px solid var(--line)}
.facts>div{display:flex;justify-content:space-between;gap:16px;padding:9px 0;border-bottom:1px solid var(--line);font-size:14px}
.facts dt{color:var(--muted)}
.facts dd{margin:0;text-align:right}
.facts a{text-decoration:underline}
.facts.row{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px;border:0;margin:0 0 32px}
.facts.row>div{display:block;border:1px solid var(--line);border-radius:12px;padding:12px 14px}
.facts.row dd{text-align:left;font-size:15px;margin-top:2px}
.toc{position:sticky;top:90px;font-size:14px;border-left:1px solid var(--line);padding-left:18px}
.toc strong{display:block;margin-bottom:8px;font-weight:600}
.toc a{display:block;color:var(--muted);text-decoration:none;padding:5px 0;line-height:1.4}
.toc a:hover,.toc a.on{color:var(--ink)}
.toc a.on{font-weight:600}
.src{margin-top:48px;padding-top:20px;border-top:1px solid var(--line);font-size:14px;color:var(--muted);max-width:70ch}
.src a{color:var(--ink)}
.rand{margin-top:20px}

footer{border-top:1px solid var(--line);padding:32px 0;color:var(--muted);font-size:14px}
footer .wrap{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}
footer a,footer b{color:var(--ink)}
footer b{font-weight:400;font-variant-numeric:tabular-nums}

/* Responsive: PC (default) > large screens > iPad/tablet > phone */
@media (min-width:1400px){.wrap{max-width:1280px}.body{font-size:17px}.summary{font-size:18px}}
@media (max-width:860px){
    .art{grid-template-columns:1fr;gap:0;padding-top:32px}
    .toc{display:none}
    .lead{grid-template-columns:240px minmax(0,1fr);gap:24px}
}
@media (max-width:720px){
    :root{--nav-h:100px}
    .nav .wrap{flex-wrap:wrap;gap:8px 12px;padding-top:8px;padding-bottom:8px;min-height:0}
    .brand{font-size:24px}
    .nav-tools{margin-left:auto}
    .nav-search{order:3;flex:1 0 100%;max-width:none;margin:0}
    .nav-search input{height:40px;font-size:16px}
}
@media (max-width:600px){
    .wrap{padding-left:max(16px,env(safe-area-inset-left));padding-right:max(16px,env(safe-area-inset-right))}
    .hero-in{padding:32px 16px}
    .hero-search .btn{padding:0 18px}
    .scroll-hint{display:none}
    section.explore{padding:48px 0 64px}
    .chips{flex-wrap:nowrap;overflow-x:auto;margin:0 -16px 24px;padding:0 16px 4px;scrollbar-width:none}
    .chips::-webkit-scrollbar{display:none}
    .chip{flex:none}
    .grid{gap:14px}
    .lead{grid-template-columns:1fr}
    .lead figure{max-width:320px}
    .art{padding:24px 0 64px}
    .body h2{font-size:26px}
    .summary{font-size:16px}
    .facts.row{grid-template-columns:1fr 1fr}
    footer .wrap{flex-direction:column}
}
@media (max-height:520px) and (orientation:landscape){.scroll-hint{display:none}.hero-in{padding:20px}}
@media (prefers-reduced-motion:reduce){
    *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important;scroll-behavior:auto!important}
}