:root{color-scheme:dark;--black:#000000;--white:#ffffff;--gold:#fcb034;--red:#8b0f04;--muted:#b6b6b6;--panel:#101010;--edge:#383838;--grid:#373737}
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.balance-equation{font-size:.9em;gap:.13em}
.signed-frac{vertical-align:middle}
.operation{display:inline-flex;align-items:center;gap:.06em}
.cancel{position:relative;display:inline-flex;align-items:center;text-decoration:none}
.cancel:after{content:"";position:absolute;left:-4%;top:50%;width:108%;height:2px;background:var(--gold);transform:rotate(-28deg)}
.mobile-source{display:none}
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