/* Mathematics layouts; all product colours and typography come from Electricity. */
body{margin:0}.np-root{grid-template-columns:minmax(0,1fr)}.np-root .ec-chapter-title{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.np-root .ec-topbar button,.np-root .ec-topbar a{flex-shrink:0}.np-root .ec-main{scroll-padding:20px}.np-root .ec-main:focus{outline:none}.np-root .ec-heading{padding-bottom:20px}.np-content{width:100%;max-width:880px;margin:auto;padding:0 22px 30px;flex-shrink:0}.np-lab{background:var(--ec-deep);border:1px solid var(--ec-border);border-radius:16px;padding:22px;margin-bottom:22px;min-width:0}.np-root h2{font-size:21px;line-height:1.35;color:var(--ec-text);margin:12px 0}.np-root h3{font-size:17px;margin:14px 0;color:var(--ec-light)}.np-root p{overflow-wrap:anywhere}.np-root .np-note{font-size:13px;color:var(--ec-muted)}.np-root .np-equation{font-size:clamp(21px,4vw,30px);line-height:1.6;color:var(--ec-cream);margin:16px 0;overflow-wrap:anywhere}.np-row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}.np-root .ec-action{min-height:44px;white-space:normal}.np-root .ec-action[aria-pressed=true]{border-color:var(--ec-mint);background:var(--ec-hover);color:var(--ec-light)}.np-control{display:block;flex:1;min-width:120px;margin:10px 0;color:var(--ec-secondary);font-size:14px}.np-control>span{display:block;margin-bottom:7px}.np-root input:not([type=range]),.np-root select{width:100%;min-height:46px;font:inherit;font-size:16px;color:var(--ec-text);background:var(--ec-bg);border:1px solid var(--ec-border);border-radius:8px;padding:10px;box-sizing:border-box}.np-root input[type=range]{width:100%;min-height:44px;accent-color:var(--ec-mint)}.np-root select{max-width:100%}.np-root input:focus-visible,.np-root select:focus-visible{outline:2px solid var(--ec-mint);outline-offset:3px}.np-feedback{color:var(--ec-light);border-left:3px solid var(--ec-mint);padding:8px 14px;min-height:40px;margin:14px 0}.np-proof{padding:8px 0 16px;color:var(--ec-secondary);line-height:1.7}.np-proof li{margin:12px 0}.np-root details{border-top:1px solid var(--ec-border);margin-top:18px;padding:10px 0}.np-root summary{min-height:44px;cursor:pointer;display:flex;align-items:center;color:var(--ec-light);font-weight:600}.np-root a{color:var(--ec-mint);text-underline-offset:4px}.np-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.np-tile{border:1px solid var(--ec-border);border-radius:10px;padding:12px;background:var(--ec-surface);min-width:0}.np-tile strong{color:var(--ec-cream);font-size:22px}.np-tile small{display:block;color:var(--ec-secondary)}.np-dots{display:flex;flex-wrap:wrap;gap:8px;margin:12px 0}.np-group{display:flex;gap:4px;flex-wrap:wrap;padding:7px;border:1px solid var(--ec-border);border-radius:8px;max-width:180px}.np-dot{display:inline-block;width:13px;height:13px;border-radius:50%;background:var(--ec-mint)}.np-dot.second{background:var(--ec-cream)}.np-dot.negative{background:transparent;border:2px solid var(--ec-cream)}.np-root .np-count{margin-left:auto;font-size:12px;color:var(--ec-secondary)}.np-root .ec-controls .ec-next{margin-left:0}.np-content svg{display:block;width:100%;height:auto;max-width:560px;margin:15px auto}.np-content svg text{font-family:inherit;font-size:24px;fill:var(--ec-text)}.np-digit{padding:12px 16px;background:var(--ec-surface);border:1px solid var(--ec-border);border-radius:9px;text-align:center;min-width:52px}.np-digit b{display:block;font-size:24px;color:var(--ec-cream)}.np-digit small{font-size:12px;color:var(--ec-secondary)}.np-result{font-variant-numeric:tabular-nums}.np-board{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));grid-template-rows:repeat(7,minmax(0,1fr));aspect-ratio:1;position:relative;max-width:400px;margin:18px auto;gap:0}.np-board svg{position:absolute;inset:0;width:100%;height:100%;margin:0;pointer-events:none}.np-board button{z-index:1;border:1px solid var(--ec-border);border-radius:50%;background:var(--ec-bg);width:40px;height:40px;align-self:center;justify-self:center;color:var(--ec-text);padding:0;min-width:44px;min-height:44px}.np-board button[data-player="1"]{background:var(--ec-mint);color:var(--ec-deep)}.np-board button[data-player="2"]{background:var(--ec-cream);color:var(--ec-deep)}.np-board button[aria-pressed=true]{outline:3px solid var(--ec-text);outline-offset:2px}.np-root .ec-map a{display:flex;gap:12px;padding:14px 0;border-bottom:1px solid var(--ec-border);font-size:14px;text-decoration:none}.np-root .ec-map h2{margin:0}.np-root .ec-map [aria-current=step]{font-weight:700;color:var(--ec-light)}.np-root .ec-map span{color:var(--ec-muted);min-width:22px}.np-question-nav{margin:15px 0}.np-letters{display:grid;grid-template-columns:repeat(auto-fit,minmax(70px,1fr));gap:10px}.np-letters .np-control{min-width:0}.np-root .np-cryptarithm{white-space:pre;font-family:ui-monospace,monospace;font-size:30px;text-align:right;line-height:1.45;max-width:240px;margin:15px auto;color:var(--ec-cream)}.np-line{border-bottom:2px solid var(--ec-border)}.np-root .np-num-grid{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:6px;margin:14px 0}.np-num-grid button{padding:6px;min-width:0}.np-root .np-num-grid .pass{background:var(--ec-hover);border-color:var(--ec-mint)}.np-root .np-num-grid .counter{border:2px dashed var(--ec-cream)}
@media(max-width:600px){.np-lab{padding:16px}.np-grid{grid-template-columns:1fr}.np-content{padding-inline:16px}.np-root .ec-heading{padding-inline:22px}.np-root .ec-controls{gap:6px}.np-root .ec-controls .ec-action{padding-inline:9px;font-size:12px}.np-board{margin-inline:-8px}.np-root .np-num-grid{grid-template-columns:repeat(5,minmax(0,1fr))}.np-root .np-count{font-size:11px}}
@media(prefers-reduced-motion:reduce){.np-root *{scroll-behavior:auto!important}}
/* Teaching layers reuse the Electricity palette and controls. */
.np-root{color-scheme:dark}.np-root select option{background:var(--ec-bg);color:var(--ec-text)}
.np-root .np-picker{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin:12px 0}.np-picker button{text-align:left;display:flex;align-items:flex-start;gap:10px}.np-picker strong{color:var(--ec-mint);flex-shrink:0}.np-picker span{font-size:14px;line-height:1.5}.np-pages{display:flex;flex-wrap:wrap;gap:8px}.np-pages button{padding:8px 12px}.np-root .np-steps{list-style-position:inside;padding:0;line-height:1.75;font-size:17px}.np-steps li{padding:14px 16px;background:var(--ec-surface);border:1px solid var(--ec-border);border-radius:10px;margin:12px 0}.np-hints{border-left:3px solid var(--ec-cream);padding:0 16px;line-height:1.7}.np-understand{margin:22px 0}.np-exam{border-top:1px solid var(--ec-border);padding-top:18px;margin-top:20px}.np-exam ol{padding-left:24px;line-height:1.8}.np-exam li{margin:12px 0}.np-guidance{margin-top:20px}.np-root .np-pair-visual{padding:12px 16px;border:1px solid var(--ec-border);border-radius:10px}.np-pair-visual .np-group{display:inline-flex;vertical-align:middle}.np-root .np-help-destination{background:var(--ec-hover);padding-inline:12px;border-radius:8px}.np-help-destination small{display:block;font-size:12px;color:var(--ec-secondary);margin-top:5px}.np-help-link{display:inline-block;margin-top:16px}.np-root .np-question h2{scroll-margin-top:20px}.np-root .np-question-list summary{font-size:16px}
@media(max-width:600px){.np-root .np-picker{grid-template-columns:1fr}.np-root .np-steps{font-size:16px}.np-steps li{padding:12px}.np-root .ec-chapter-title{font-size:15px}}

.np-root li{overflow-wrap:anywhere}.np-question h2:focus{outline:none}
/* Keep intentionally separated comparisons readable within the existing step cards. */
.np-root .np-steps li{white-space:pre-line}