*{box-sizing:border-box}
body{margin:0;background:#fff;color:#251f21;font:16px/26px system-ui,-apple-system,"Segoe UI",Arial,sans-serif}
main{max-width:760px;margin:0 auto;padding:24px 20px 48px}
h1{font:400 30px/38px Georgia,"Times New Roman",serif;margin:8px 0 4px}
h2{font:400 22px/30px Georgia,serif;margin:26px 0 8px}
h4{font-weight:400;color:#585254;font-size:14px;margin:22px 0 8px}
h3{font-size:16px;font-weight:600;margin:18px 0 6px}
.fact,.closing{color:#585254;font-size:14px;margin:0 0 8px}
.intro{margin:14px 0 18px}
nav{display:flex;gap:6px 20px;flex-wrap:wrap;border-bottom:1px solid #eae9ea;margin-bottom:8px}
nav button{background:none;border:0;font:inherit;color:#585254;padding:10px 0;min-height:44px;cursor:pointer}
nav button.on{color:#251f21;box-shadow:inset 0 -2px 0 #251f21}
.board{width:100%;height:auto;border-radius:12px;display:block;margin:6px 0 8px}
.m{unicode-bidi:isolate-override;direction:ltr;display:inline-block;white-space:nowrap}
.eq,.qbox{direction:ltr;text-align:left;unicode-bidi:isolate-override;font-size:17px;line-height:28px;padding:6px 12px;margin:6px 0 14px;background:#f4efec;border-radius:4px;overflow-x:auto;white-space:nowrap}
.qbox{background:none;border:1px solid #eae9ea;border-radius:8px;padding:10px 12px}
.eq.answer{border:1px solid #73a89a;background:none;font-weight:600}
.step{margin:0 0 4px}
details{border:1px solid #eae9ea;border-radius:8px;margin:12px 0;padding:0 14px}
summary{cursor:pointer;padding:12px 0;font-weight:600}
details[open]{padding-bottom:8px}
details[open]>summary{border-bottom:1px solid #eae9ea;margin-bottom:12px}
.callout{background:#f4efec;border-radius:8px;padding:12px 14px;margin:12px 0}
.callout p{margin:4px 0 0}
.callout.note{background:none;border-inline-start:3px solid #eae9ea;border-radius:0}
table{width:100%;border-collapse:collapse;margin:8px 0 14px}
th,td{text-align:right;padding:8px 6px;border-bottom:1px solid #eae9ea;vertical-align:top}
th{font-weight:600;color:#585254}
ul,ol{padding-inline-start:22px;margin:6px 0 12px}li{margin-bottom:6px}
p{margin:0 0 10px}
.tf{margin:14px 0 4px}