/* Equal factors make a square; keep the extra learning area compact when closed. */
.squares-card {margin:24px 0;border:1px solid var(--line);border-radius:18px;background:#fff;color:var(--ink);overflow-wrap:anywhere;hyphens:auto;}
.squares-card>summary {min-height:72px;padding:18px;cursor:pointer;font-size:24px;font-weight:700;line-height:1.4;}
.squares-icon {display:inline-block;width:30px;height:30px;margin:0 8px 0 2px;vertical-align:-5px;fill:currentColor;}
.squares-body {padding:0 20px 20px;}
.squares-body>p {margin:0 0 16px;line-height:1.5;}
.squares-picker {display:flex;flex-wrap:wrap;align-items:center;gap:10px;font-weight:600;}
.squares-picker select {-webkit-appearance:none;appearance:none;min-height:48px;max-width:100%;padding:8px 40px 8px 14px;border:2px solid #506780;border-radius:10px;background-color:#fff;background-image:linear-gradient(45deg,transparent 50%,currentColor 50%),linear-gradient(135deg,currentColor 50%,transparent 50%);background-position:calc(100% - 19px) 50%,calc(100% - 13px) 50%;background-size:6px 6px;background-repeat:no-repeat;color:var(--ink);font:inherit;line-height:1.4;}
.squares-figure {max-width:360px;margin:20px auto;text-align:center;}
.squares-figure>svg {display:block;max-width:100%;height:auto;margin:auto;fill:var(--ink);}
.square-outline {fill:none;stroke:currentColor;stroke-width:1.5;}
.squares-figure figcaption {margin-top:8px;font-weight:600;line-height:1.5;}
.square-equation {margin:16px 0 10px;padding:12px;border:2px solid #506780;border-radius:12px;background:#fff3bd;text-align:center;font-size:clamp(26px,5vw,36px);font-weight:700;line-height:1.4;}
.square-inverse {text-align:center;font-weight:600;}
.squares-practice {display:block;margin:20px auto 10px;max-width:100%;}
.squares-round-hint {text-align:center;font-size:16px;color:var(--muted);}
.squares-overview {margin-top:20px;border-top:1px solid var(--line);}
.squares-overview>summary {min-height:48px;padding:12px 0;cursor:pointer;font-weight:600;line-height:1.5;}
#square-overview {display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,150px),1fr));gap:8px;margin:8px 0 0;padding:0;list-style:none;}
#square-overview li {padding:10px;border:1px solid var(--line);border-radius:8px;line-height:1.5;}
@media(max-width:450px) {
  .squares-card>summary {padding:16px 12px;font-size:22px;}
  .squares-body {padding:0 14px 16px;}
}
@media(forced-colors:active) {
  .squares-figure>svg {fill:CanvasText;}
  .square-outline {stroke:CanvasText;}
}