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var(--body);border:0;border-radius:0;flex-direction:column;justify-content:center;align-items:center;padding:8px 2px;display:flex;position:relative}.fl-part+.fl-part{border-left:2px solid var(--ink)}.fl-part-coloured{background:var(--sun)}.fl-bar-interactive .fl-part{cursor:pointer;touch-action:manipulation}.fl-bar-interactive .fl-part[aria-disabled=true]{cursor:default}.fl-bar-interactive .fl-part:focus-visible{z-index:1;outline:3px solid var(--navy);outline-offset:-6px}.fl-part-check{font-size:1.7rem;line-height:1.2}.fl-part-number{line-height:1.3}.fl-notation{min-width:1.6em;color:var(--ink);text-align:center;vertical-align:middle;grid-template-rows:1fr 1fr;font-size:2rem;font-weight:700;line-height:1.2;display:inline-grid}.fl-numerator{border-bottom:3px solid;padding:0 7px 4px}.fl-denominator{padding:4px 7px 0}.fl-notation-explained{align-items:stretch;gap:18px;margin:12px 0;display:inline-flex}.fl-notation-labels{grid-template-rows:1fr 1fr;font-size:1.1rem;line-height:1.4;display:grid}.fl-notation-labels>span{align-items:center;padding-block:4px;display:flex}.tl-card .fl-section-label{margin:20px 0 10px;font-size:1.15rem;font-weight:700}.tl-card .fl-lesson-note{max-width:34em;margin-top:16px}.fl-options{flex-wrap:wrap;gap:16px;margin-top:24px;display:flex}.fl-options>button{min-width:80px;min-height:52px}.fl-example{border:2px dashed var(--slate);margin-top:20px;padding:20px}.tl-card .fl-example h3{margin-bottom:12px;font-size:1.3rem}.fl-example .fl-bar{margin-block:16px}.tl-card .fl-example p+p{margin-top:12px}.fl-unit-menu{border-top:2px solid var(--mist);margin-top:28px;padding-top:16px}.fl-unit-menu>summary{min-height:48px;color:var(--navy);cursor:pointer;padding-block:8px;font-weight:700;display:list-item}.fl-unit-buttons{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:16px 0 8px;display:grid}.fl-unit-buttons>button{text-align:left;min-height:60px}.fl-fraction-choices,.tl-choices.fl-fraction-choices{grid-template-columns:repeat(3,minmax(0,1fr));justify-content:stretch;gap:18px;max-width:480px;margin-top:24px;display:grid}.fl-fraction-choices>button,.tl-choices.fl-fraction-choices>.btn{flex-direction:column;justify-content:center;align-items:center;gap:12px;min-width:0;min-height:108px;padding:14px 8px;display:flex}.fl-choice-word{font-size:1rem;line-height:1.4;display:block}.fl-comparison{gap:20px;max-width:480px;margin-top:24px;display:grid}.fl-comparison>*{min-width:0}.fl-comparison .fl-bar{margin-block:12px}.fl-check-actions{flex-wrap:wrap;align-items:center;gap:12px 24px;margin-top:24px;display:flex}.tl-card .fl-practice-target{flex-wrap:wrap;align-items:center;gap:16px;margin-block:20px;font-size:1.25rem;display:flex}.tl-card .fl-practice-question{margin-top:16px;font-size:1.25rem}.fl-help{border-left:4px solid var(--navy);margin-top:20px;padding:12px 16px}.tl-card .fl-help p+p{margin-top:12px}.fl-help-actions{flex-wrap:wrap;align-items:center;gap:12px 24px;margin-top:16px;display:flex}@media (width<=520px){.fl-unit-buttons{grid-template-columns:minmax(0,1fr)}.fl-example{padding:14px 12px}}@media (width<=359px){.fl-fraction-choices,.tl-choices.fl-fraction-choices{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.fl-notation-explained{gap:12px}.fl-notation-labels{font-size:1rem}}