/* PolyTools — shared styles for the home page and the blog (the course page has its own inline styles) */
:root{
  --bg:#07090f;--bg-2:#0b0e16;--card:#10141e;--card-2:#161b28;
  --line:rgba(255,255,255,.08);--line-2:rgba(255,255,255,.14);
  --text:#ece8e1;--text-2:#d6d1c8;--muted:#a19d95;--dim:#6b6862;
  --gold:#e8b65a;--gold-2:#f5d08a;--teal:#46c2d6;--blue:#3d7bfd;--yes:#2fcf6f;--no:#f0564f;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --serif:"Iowan Old Style","Palatino Linotype",Palatino,"Book Antiqua",Georgia,"Times New Roman",serif;
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --hdr:64px;
}
html[lang^=zh]{
  --sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC","Segoe UI",Roboto,Arial,sans-serif;
  --serif:"Songti SC","STSong","Noto Serif SC","Source Han Serif SC","SimSun",serif;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;background:var(--bg)}
body{background:var(--bg);color:var(--text);font-family:var(--sans);font-size:17px;line-height:1.7;overflow-x:hidden;-webkit-font-smoothing:antialiased}
::selection{background:rgba(232,182,90,.35);color:#fff}
a{color:var(--teal);text-decoration:none}
a:hover{text-decoration:underline}
img,svg{display:block;max-width:100%}
button{font-family:inherit}
b,strong{font-weight:700;color:#fff}
p{margin:0 0 16px}
p:last-child{margin-bottom:0}
[id]{scroll-margin-top:calc(var(--hdr) + 16px)}
.wrap{max-width:1160px;margin:0 auto;padding:0 28px}
.narrow{max-width:780px}
@media(max-width:600px){.wrap{padding:0 18px}body{font-size:16.5px}}

.grain{position:fixed;inset:-8%;z-index:90;pointer-events:none;opacity:.05;
  background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='180' height='180'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 .6 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>")}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;font-family:var(--sans);font-weight:700;font-size:15px;color:#fff;
  background:linear-gradient(135deg,#4b86ff,#2f62e6);border:none;border-radius:12px;padding:12px 22px;cursor:pointer;white-space:nowrap;
  box-shadow:0 6px 24px rgba(61,123,253,.25);transition:transform .15s,box-shadow .2s,filter .15s}
.btn:hover{transform:translateY(-1px);box-shadow:0 10px 34px rgba(61,123,253,.42);filter:brightness(1.07);text-decoration:none}
.btn.gold{background:linear-gradient(135deg,#f0c56c,#d9a24a);color:#1a1205;box-shadow:0 6px 24px rgba(232,182,90,.25)}
.btn.gold:hover{box-shadow:0 10px 34px rgba(232,182,90,.4)}
.btn.ghost{background:transparent;border:1px solid var(--line-2);box-shadow:none;color:var(--text)}
.btn.ghost:hover{border-color:var(--gold)}
.btn.big{padding:16px 28px;font-size:16.5px;border-radius:14px}
.btn.small{padding:9px 16px;font-size:14px;border-radius:10px}
.btn svg{width:17px;height:17px;flex:none}

/* header */
.top{position:fixed;top:0;left:0;right:0;z-index:50;border-bottom:1px solid transparent;transition:background .3s,border-color .3s}
.top.solid,.top.open{background:rgba(7,9,15,.88);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);border-bottom-color:var(--line)}
.top-in{display:flex;align-items:center;gap:18px;height:var(--hdr);max-width:1240px;margin:0 auto;padding:0 28px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px;color:var(--text);flex:none;letter-spacing:-.01em}
.logo:hover{text-decoration:none}
.logo svg{width:32px;height:32px}
.logo b{color:var(--gold)}
.nav{display:flex;gap:4px;margin-left:12px}
.nav a{padding:8px 12px;border-radius:9px;font-size:14.5px;font-weight:600;color:var(--muted)}
.nav a:hover,.nav a[aria-current=page]{color:var(--text);background:rgba(255,255,255,.05);text-decoration:none}
.top .sp{flex:1}
.icon-btn{flex:none;display:flex;align-items:center;justify-content:center;width:40px;height:40px;border-radius:10px;border:1px solid var(--line-2);
  background:rgba(7,9,15,.4);color:var(--text);cursor:pointer;transition:border-color .15s}
.icon-btn:hover{border-color:var(--gold);text-decoration:none}
.icon-btn svg{width:16px;height:16px}
.menu-btn{display:none}
.lang{position:relative;flex:none}
.lang-btn{display:inline-flex;align-items:center;gap:7px;height:40px;padding:0 11px;font-family:var(--sans);font-size:13.5px;font-weight:700;letter-spacing:.03em;
  color:var(--text);background:rgba(7,9,15,.4);border:1px solid var(--line-2);border-radius:10px;cursor:pointer}
.lang-btn:hover,.lang-btn[aria-expanded=true]{border-color:var(--gold)}
.lang-btn svg{width:16px;height:16px;color:var(--gold)}
.lang-btn .caret{width:10px;height:10px;color:var(--muted)}
.lang-menu{position:absolute;right:0;top:calc(100% + 8px);min-width:190px;z-index:70;background:var(--card-2);border:1px solid var(--line-2);border-radius:14px;padding:6px;box-shadow:0 18px 50px rgba(0,0,0,.55)}
.lang-menu[hidden]{display:none}
.lang-menu a{display:flex;align-items:center;justify-content:space-between;gap:14px;min-height:42px;padding:9px 12px;border-radius:9px;font-size:14.5px;font-weight:600;color:var(--text)}
.lang-menu a:hover,.lang-menu a:focus-visible{background:rgba(232,182,90,.12);text-decoration:none;outline:none}
.lang-menu a small{font-family:var(--mono);font-size:11.5px;color:var(--muted)}
.lang-menu a[aria-current=true]{color:var(--gold)}
.lang-menu a[aria-current=true] small::before{content:"✓ ";color:var(--gold)}
.mnav{display:none}
@media(max-width:960px){
  .nav{display:none}
  .menu-btn{display:flex}
  .top .cta-full{display:none}
  .mnav{display:block;position:fixed;top:var(--hdr);left:0;right:0;z-index:49;background:#07090f;border-bottom:1px solid var(--line);padding:10px 18px 18px}
  .mnav[hidden]{display:none}
  .mnav a{display:flex;align-items:center;gap:10px;min-height:48px;padding:0 10px;border-radius:10px;font-size:16px;font-weight:600;color:var(--text)}
  .mnav a:hover{background:rgba(255,255,255,.05);text-decoration:none}
  .mnav a svg{width:16px;height:16px}
}
@media(max-width:520px){
  .top-in{gap:8px;padding:0 14px}
  .logo{font-size:18px;gap:8px}
  .logo svg{width:28px;height:28px}
}
@media(max-width:430px){.top .x-top{display:none}}
@media(max-width:340px){.logo span{display:none}}
@media(pointer:coarse){.icon-btn,.lang-btn{height:44px}.icon-btn{width:44px}}

/* sections */
.section{padding:110px 0;position:relative}
@media(max-width:600px){.section{padding:64px 0}}
.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.32em;text-transform:uppercase;color:var(--gold);margin-bottom:14px}
.h2{font-family:var(--serif);font-size:clamp(32px,4.6vw,54px);font-weight:700;line-height:1.08;margin-bottom:16px;letter-spacing:-.01em}
.lead{color:var(--muted);font-size:18px;max-width:680px}
.center{text-align:center}
.center .lead{margin:0 auto}
.rv{opacity:0;transform:translateY(24px);transition:opacity .8s ease,transform .8s cubic-bezier(.2,.7,.2,1)}
.rv.in{opacity:1;transform:none}

/* referral link on the word "Polymarket" */
.pm-link{color:inherit;text-decoration:underline;text-decoration-color:rgba(232,182,90,.6);text-decoration-thickness:1.5px;text-underline-offset:3px;transition:color .15s}
.pm-link:hover{color:var(--gold-2);text-decoration-color:var(--gold-2)}

/* footer */
footer{border-top:1px solid var(--line);padding:44px 0 50px;margin-top:40px}
.foot{display:grid;grid-template-columns:1.2fr 1fr;gap:30px}
.foot .logo{margin-bottom:12px}
.foot-links{display:flex;flex-wrap:wrap;gap:8px 22px;justify-content:flex-end;align-content:flex-start}
.foot-links a{color:var(--muted);font-weight:600;font-size:14.5px;display:inline-flex;align-items:center;gap:7px}
.foot-links a:hover{color:var(--text);text-decoration:none}
.foot-links svg{width:14px;height:14px}
.disclaimer{grid-column:1/-1;font-size:12.5px;color:#64615b;line-height:1.6;max-width:900px}
.disclaimer a{color:inherit;text-decoration:underline;text-underline-offset:2px}
.disclaimer a:hover{color:var(--muted)}
@media(max-width:700px){.foot{grid-template-columns:1fr}.foot-links{justify-content:flex-start}}

/* blog */
.post-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.post-card{display:flex;flex-direction:column;border-radius:18px;overflow:hidden;background:linear-gradient(180deg,var(--card-2),var(--card));border:1px solid var(--line);
  color:var(--text);transition:border-color .25s,transform .25s}
.post-card:hover{border-color:rgba(232,182,90,.5);transform:translateY(-3px);text-decoration:none}
.post-cover{position:relative;aspect-ratio:16/9;overflow:hidden;background:#0c0f17;border-bottom:1px solid var(--line)}
.post-cover svg,.post-cover img{width:100%;height:100%;object-fit:cover}
.post-body{display:flex;flex-direction:column;flex:1;padding:20px 22px 22px}
.post-meta{font-family:var(--mono);font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--gold);margin-bottom:10px;line-height:1.5}
@media(max-width:640px){.post-meta{font-size:11px;letter-spacing:.03em;margin-bottom:12px}}
.post-card h3{font-family:var(--serif);font-size:21px;line-height:1.25;margin-bottom:10px}
.post-card p{font-size:14.5px;color:var(--muted);line-height:1.55;margin:0}
.post-more{margin-top:auto;padding-top:16px;font-size:14px;font-weight:700;color:var(--gold)}
@media(max-width:980px){.post-grid{grid-template-columns:1fr 1fr}}
@media(max-width:640px){.post-grid{grid-template-columns:1fr}}

.article{padding:calc(var(--hdr) + 60px) 0 40px}
.article-head{max-width:780px;margin:0 auto 40px}
.crumbs{font-size:14px;color:var(--muted);margin-bottom:20px}
.crumbs a{color:var(--muted)}
.crumbs a:hover{color:var(--text)}
.article h1{font-family:var(--serif);font-size:clamp(34px,5vw,56px);line-height:1.08;letter-spacing:-.01em;margin-bottom:18px}
.article .dek{font-size:19px;color:var(--muted);line-height:1.6}
.article .meta-line{display:flex;flex-wrap:wrap;gap:8px 18px;margin-top:20px;font-family:var(--mono);font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:var(--dim)}
.prose{max-width:740px;margin:0 auto;font-size:18px;line-height:1.75;color:var(--text-2)}
.prose h2{font-family:var(--serif);font-size:30px;line-height:1.2;color:var(--text);margin:46px 0 14px}
.prose h3{font-size:20px;color:var(--text);margin:30px 0 10px}
.prose p{margin:0 0 20px}
.prose ul,.prose ol{margin:0 0 22px 22px}
.prose li{margin-bottom:8px}
.prose blockquote{margin:26px 0;padding:18px 22px;border-left:3px solid var(--gold);background:rgba(232,182,90,.06);border-radius:0 12px 12px 0;font-family:var(--serif);font-size:19px;color:#efe7d6}
.prose .callout{margin:26px 0;padding:18px 22px;border:1px solid rgba(70,194,214,.35);background:rgba(70,194,214,.06);border-radius:14px;font-size:16px}
.prose .table-wrap{margin:22px 0;overflow-x:auto;-webkit-overflow-scrolling:touch}
.prose table{width:100%;border-collapse:collapse;font-size:15px}
.prose th,.prose td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line)}
.prose th{color:var(--text);font-weight:700;background:rgba(255,255,255,.03)}
.prose code{font-family:var(--mono);font-size:.88em;background:rgba(255,255,255,.07);border-radius:6px;padding:2px 7px}
.sources{max-width:740px;margin:40px auto 0;padding-top:24px;border-top:1px dashed var(--line);font-size:14.5px;color:var(--muted)}
.sources h2{font-family:var(--mono);font-size:12px;letter-spacing:.2em;text-transform:uppercase;color:var(--gold);margin-bottom:12px}
.sources ol{margin-left:20px}
.sources li{margin-bottom:6px}
.article-cta{max-width:780px;margin:50px auto 0;padding:30px;border-radius:20px;border:1px solid rgba(232,182,90,.35);
  background:radial-gradient(70% 120% at 50% -20%,rgba(232,182,90,.16),transparent 65%),var(--card);text-align:center}
.article-cta h2{font-family:var(--serif);font-size:28px;margin-bottom:10px}
.article-cta p{color:var(--muted);margin-bottom:20px}
.article-cta .row{display:flex;flex-wrap:wrap;gap:12px;justify-content:center}
.article-cta .note{font-size:12.5px;margin:16px 0 0}
@media(max-width:600px){.prose{font-size:17px}.prose h2{font-size:25px}.article-cta{padding:24px 16px}.article-cta .btn{white-space:normal}}

@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation-duration:0s!important;animation-iteration-count:1!important}
  .rv{opacity:1;transform:none}
}

/* typography: balanced headings, no lonely last word; CJK needs upright glyphs, looser lines, tighter tracking */
h1,h2,h3{text-wrap:balance}
p,li{text-wrap:pretty}
.article-cta h2{line-height:1.2}
html[lang^=zh] em,html[lang^=zh] i,html[lang^=zh] .hero h1 em{font-style:normal}
html[lang^=zh] :is(h1,h2,h3){line-height:1.3}
html[lang^=zh] :is(.eyebrow,.badge,.post-meta,.hero-facts,.meta-line){letter-spacing:.06em}