/* AI Trading Arena (/arena). Layout on base.css + check.css (DESIGN.md). */
.ar-warn{margin:16px 0 0;font-size:14px;color:var(--ink-subtle)}
.ar-panel{margin:40px 0 0;padding:24px;border:1px solid var(--hairline);border-radius:var(--r-panel);background:var(--surface-1)}
.ar-panel-head{display:flex;flex-wrap:wrap;align-items:baseline;justify-content:space-between;gap:8px;margin-bottom:12px}
.ar-panel-head h2{font-size:20px}
.ar-status{margin:12px 0 0;padding-top:12px;border-top:1px solid var(--hairline);font-size:14px;color:var(--ink-subtle)}
.ar-chart{margin:0}
.ar-chart canvas{display:block;width:100%;height:420px}
@media (max-width:640px){.ar-chart canvas{height:280px}}
.ar-chart figcaption{display:flex;flex-wrap:wrap;gap:4px 16px;margin-top:12px;font-size:13px;color:var(--ink-subtle)}
.ar-chart figcaption span{display:inline-flex;align-items:center;gap:6px}
.ar-chart figcaption i{display:inline-block;width:14px;height:3px;border-radius:2px;background:var(--c)}
.ar-chart figcaption i.dash{background:repeating-linear-gradient(90deg,var(--c) 0 4px,transparent 4px 7px)}
.ar-sec{margin-top:80px}
.ar-sec>h2{margin:0 0 8px}
.ar-sub{max-width:64ch;margin:0 0 24px;color:var(--ink-subtle)}

/* leaderboard: grid rows (table semantics via role), cards on phones */
.ar-board{border:1px solid var(--hairline);border-radius:var(--r-panel);background:var(--surface-1);overflow:hidden}
.ar-row{display:grid;grid-template-columns:36px minmax(160px,1.6fr) repeat(4,minmax(80px,1fr)) minmax(200px,2fr);align-items:center;gap:12px;padding:14px 20px;border-bottom:1px solid var(--hairline)}
.ar-row:last-child{border-bottom:0}
.ar-row.head{padding:10px 20px;background:var(--surface-2);font-size:13px;color:var(--ink-subtle)}
.ar-row.sk{height:52px;background:var(--surface-1)}
.ar-row .rk{font:500 14px var(--mono);color:var(--ink-faint)}
.ar-row .nm{color:var(--ink);font-weight:600}
.ar-row .nm small{display:block;font-weight:400;font-size:12.5px;color:var(--ink-faint)}
.ar-row .n{font:500 15px var(--mono);font-variant-numeric:tabular-nums;color:var(--ink);text-align:right}
.ar-row.head .n{font:inherit;color:inherit}
.ar-row .stats{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;font:500 14px var(--mono);text-align:right;color:var(--ink-muted)}
.ar-row .stats.wait{grid-template-columns:1fr;font:13px var(--body);color:var(--ink-faint);text-align:right}
.ar-row.base .nm{color:var(--ink-muted)}
.ar-row .up{color:var(--up)}.ar-row .down{color:var(--down)}

/* lessons + decisions */
.ar-lessons,.ar-notes{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.ar-card{padding:20px;border:1px solid var(--hairline);border-radius:var(--r-panel);background:var(--surface-1)}
.ar-card h3{font-size:17px}
.ar-card .meta{margin:4px 0 12px;font:13px var(--mono);color:var(--ink-faint)}
.ar-card p{font-size:15px}
.ar-card .lesson{color:var(--ink)}
.ar-card dl{margin:12px 0 0;font-size:14px}
.ar-card dt{color:var(--ink-subtle);margin-top:8px}
.ar-card dd{margin:2px 0 0;color:var(--ink-muted)}
.ar-empty{grid-column:1/-1;padding:24px;border:1px dashed var(--hairline-strong);border-radius:var(--r-panel);color:var(--ink-subtle)}
.ar-reason{display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden}
.ar-card.open .ar-reason{display:block}
.ar-more{min-height:44px;padding:0;border:0;background:none;color:var(--ink);font:600 14px var(--body);text-decoration:underline;text-underline-offset:3px;cursor:pointer}
.ar-trades{margin:12px 0 0;padding:12px 0 0;list-style:none;border-top:1px solid var(--hairline);font:13px var(--mono);color:var(--ink-subtle)}
.ar-trades li{padding:3px 0}
.ar-trades .buy{color:var(--up)}.ar-trades .sell{color:var(--down)}

/* weekly pick */
.ar-picks{display:flex;flex-wrap:wrap;gap:8px}
.ar-pick{display:flex;flex-direction:column;align-items:flex-start;gap:2px;min-height:56px;padding:8px 14px;border:1px solid var(--hairline-strong);border-radius:var(--r-ctl);background:var(--surface-1);color:var(--ink);font:600 15px var(--body);cursor:pointer;transition:border-color .15s var(--ease)}
.ar-pick small{font:12.5px var(--mono);color:var(--ink-faint)}
.ar-pick:hover:not(:disabled){border-color:var(--ink-faint)}
.ar-pick.on{border-color:var(--accent);background:var(--accent-soft)}
.ar-pick:disabled{cursor:default}
.ar-points{margin:12px 0 0;font-size:14px;color:var(--ink-subtle)}

@media (max-width:900px){
  .ar-row.head{display:none}
  .ar-row{grid-template-columns:24px repeat(3,1fr);grid-template-areas:"rk nm nm val" "rk ret bh tr" "rk st st st";row-gap:10px;column-gap:12px;padding:16px}
  .ar-row .rk{grid-area:rk;align-self:start;padding-top:2px}
  .ar-row .nm{grid-area:nm}
  .ar-row .v{grid-area:val;text-align:right}
  .ar-row .r{grid-area:ret}.ar-row .bh{grid-area:bh}.ar-row .tr{grid-area:tr}
  .ar-row .r,.ar-row .bh,.ar-row .tr{text-align:left;font-size:14px}
  .ar-row .r::before,.ar-row .bh::before,.ar-row .tr::before{content:attr(data-l);display:block;font:12px var(--body);color:var(--ink-faint)}
  .ar-row .stats{grid-area:st;text-align:left}
  .ar-row .stats.wait{text-align:left}
  .ar-lessons,.ar-notes{grid-template-columns:1fr}
  .ar-panel{padding:16px}
}