.ar{background:var(--ground);color:var(--ink-2)}.ar-hero,.ar-band,.ar-block,.ar-related{width:100%;max-width:calc(var(--wrap-max) + 2 * var(--gutter-page));padding-inline:var(--gutter-page);margin-inline:auto}.ar-hero{grid-template-columns:minmax(0,1fr) minmax(0,1.05fr);align-items:center;gap:clamp(24px,4vw,64px);padding-block:clamp(28px,5vh,56px) clamp(32px,5vh,64px);display:grid}.ar-hero--single{grid-template-columns:minmax(0,1fr)}.ar-hero__text{min-width:0}.ar-back{min-height:44px;color:var(--ink-3);transition:color .3s var(--ease);align-items:center;gap:.6rem;font-size:.875rem;font-weight:500;text-decoration:none;display:inline-flex}.ar-back:hover{color:var(--link)}.ar-eyebrow{color:var(--cyan-deep);font-family:var(--font-display);margin:1.4rem 0 0;font-size:1.1875rem;font-style:italic;line-height:1.3}.ar h1{max-width:20ch;font-size:var(--fs-h1);margin:.9rem 0 0;line-height:1.04}.ar-hero--single h1{max-width:22ch}.ar-answer{max-width:34em;color:var(--ink-2);font-size:var(--fs-lede);text-wrap:pretty;margin:1.4rem 0 0;line-height:1.6}.ar-hero__actions{margin-block-start:1.8rem}.ar-direct{color:var(--ink-3);font-size:var(--fs-small);margin:.2rem 0 0}.ar-direct a{color:var(--link);font-weight:500}.ar-byline{border-block-start:var(--hairline) solid var(--hair-strong);color:var(--ink-3);font-size:var(--fs-caption);margin:1.4rem 0 0;padding-block-start:1rem;line-height:1.5}.ar-byline a{color:var(--link)}.ar-byline time{font-variant-numeric:tabular-nums}.ar-hero__fig{min-width:0;margin-inline-end:calc(var(--gutter-page) * -.6);position:relative}.ar-label{color:var(--cyan-deep);font-family:var(--font-display);margin:0;font-size:1.1875rem;font-style:italic;line-height:1.3}.ar-band{padding-block:clamp(40px,5vw,72px)}.ar-band h2{max-width:24ch;font-size:var(--fs-h2);margin:.9rem 0 0;line-height:1.08}.ar-problem-deck{max-width:38em;color:var(--ink);font-family:var(--font-display);letter-spacing:-.012em;margin:1.4rem 0 0;font-size:clamp(1.35rem,1.1rem + 1vw,1.875rem);line-height:1.32}.ar-problem-detail{max-width:40em;font-size:var(--fs-body);margin:1.4rem 0 0;line-height:1.65}.ar-block{border-block-start:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,13rem) minmax(0,1fr);align-items:start;gap:clamp(1.5rem,6vw,6rem);padding-block:clamp(2.5rem,4.4vw,4.25rem);display:grid}.ar-block--follow{border-block-start-color:#0000;padding-block-start:0}.ar-side{top:calc(var(--header-height) + 1.5rem);position:sticky}.ar-h2{max-width:22ch;font-size:var(--fs-h3);margin:0 0 1.4rem;line-height:1.15}.ar-rows .ar-h2--tight{margin-block-start:2.6rem}.ar-rows .ar-h2--wide{max-width:30ch}.ar-rows{min-width:0;max-width:54rem}.ar-rows--wide{max-width:66rem}.ar-rows h3{color:var(--ink);font-family:var(--font-sans);letter-spacing:-.01em;margin:0 0 .45rem;font-size:1.0625rem;font-weight:600}.ar-rows p{font-size:var(--fs-body);margin:0;line-height:1.62}.ar-note,.ar-rows .ar-note{font-size:var(--fs-body);margin:0 0 1.25rem;line-height:1.65}.ar-rows .ar-note:last-child{margin-block-end:0}.ar-rows .ar-note--after{margin-block-start:1.6rem}.ar-note a,.ar-links a,.ar-ledger a,.ar-gate a{color:var(--link);text-underline-offset:.28em;font-weight:500;text-decoration-thickness:1px}.ar-sheet{background:linear-gradient(170deg, var(--paper) 0%, var(--paper-edge) 100%);border-radius:3px;max-width:44rem;padding:clamp(22px,3vw,34px) clamp(20px,3vw,36px) clamp(10px,2vw,18px) clamp(30px,3.4vw,44px);position:relative;box-shadow:inset 0 0 0 1px #13252e0f,0 1px 1px #13252e1a,0 24px 40px -28px #13252e6b}.ar-sheet:before{content:"";background:linear-gradient(90deg, #0003, #ffffff24 45%, #0000001f), var(--cloth-sand);border-radius:3px 0 0 3px;width:12px;position:absolute;top:0;bottom:0;left:0}.ar-rows .ar-sheet__title{color:var(--ink);font-family:var(--font-display);font-size:var(--fs-h3);margin:0 0 8px;line-height:1.15}.ar-sheet__list{margin:0;padding:0;list-style:none;display:grid}.ar-sheet__list li{border-top:var(--hairline) solid var(--hair);color:var(--ink-2);font-size:var(--fs-body);padding:16px 0 16px 38px;line-height:1.5;position:relative}.ar-sheet__box{width:20px;height:20px;box-shadow:inset 0 0 0 1.5px var(--ink-3);border-radius:4px;position:absolute;top:18px;left:0}.ar-bill{border-block-start:var(--hairline) solid var(--hair-strong);margin:0;padding:0;list-style:none;display:grid}.ar-bill li{border-block-end:var(--hairline) solid var(--hair);grid-template-columns:2.4rem minmax(0,.8fr) minmax(0,1.2fr);align-items:baseline;gap:4px clamp(16px,3vw,48px);padding:22px 0;display:grid}.ar-bill__n{color:var(--cyan-deep);font-family:var(--font-display);font-variant-numeric:tabular-nums;font-size:1rem;font-style:italic}.ar-rows .ar-bill h3{color:var(--ink);font-family:var(--font-display);letter-spacing:-.01em;margin:0;font-size:1.375rem;font-weight:400;line-height:1.2}.ar-bill p{color:var(--ink-2);font-size:var(--fs-small);line-height:1.6}.ar-gate{background:linear-gradient(170deg, var(--paper) 0%, var(--paper-edge) 100%);border-radius:3px;padding:clamp(20px,2.6vw,30px) clamp(18px,2.6vw,32px) clamp(14px,2vw,20px) clamp(28px,3.2vw,42px);position:relative;box-shadow:inset 0 0 0 1px #13252e0f,0 1px 1px #13252e1a,0 24px 40px -28px #13252e6b}.ar-gate:before{content:"";background:linear-gradient(90deg, #0003, #ffffff24 45%, #0000001f), var(--cloth-sand);border-radius:3px 0 0 3px;width:12px;position:absolute;top:0;bottom:0;left:0}.ar-gate figcaption{color:var(--cyan-deep);font-family:var(--font-display);margin:0 0 6px;font-size:1.125rem;font-style:italic;line-height:1.3}.ar-gate ol{margin:0;padding:0;list-style:none}.ar-gate li{border-top:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,1.25fr) minmax(0,1fr);align-items:baseline;gap:4px clamp(14px,2vw,28px);padding:13px 0;display:grid}.ar-gate li b{color:var(--ink);font-family:var(--font-display);font-size:1.125rem;font-weight:400;line-height:1.25;display:block}.ar-gate li div i{color:var(--ink-3);font-family:var(--font-sans);font-size:var(--fs-caption);margin-top:2px;font-style:normal;line-height:1.4;display:block}.ar-gate li span{color:var(--ink-2);font-size:var(--fs-small);line-height:1.45}.ar-gate li.is-pay span{color:var(--ink);font-weight:600}.ar-gate>p{color:var(--ink-3);font-family:var(--font-display);margin:12px 0 0;font-size:.9375rem;font-style:italic;line-height:1.4}.ar-ledger{background:linear-gradient(170deg, var(--paper) 0%, var(--paper-edge) 100%);border-radius:4px;max-width:52rem;margin:1.6rem 0 0;padding:22px clamp(18px,3vw,32px) 18px clamp(30px,3.4vw,44px);position:relative;box-shadow:inset 0 0 0 1px #13252e0f,0 1px 1px #13252e1a,0 24px 40px -28px #13252e6b}.ar-ledger:before{content:"";background:linear-gradient(90deg, #0003, #ffffff24 45%, #0000001f), var(--cloth-sand);border-radius:4px 0 0 4px;width:12px;position:absolute;top:0;bottom:0;left:0}.ar-ledger figcaption{color:var(--cyan-deep);font-family:var(--font-display);margin-bottom:4px;font-size:1.125rem;font-style:italic;line-height:1.3}.ar-ledger__window{color:var(--ink-3);font-size:var(--fs-caption);margin:0 0 8px;line-height:1.45}.ar-ledger ol{margin:0;padding:0;list-style:none}.ar-ledger li{border-top:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,1.15fr) 5.5rem minmax(0,1.6fr);align-items:baseline;gap:4px clamp(12px,2vw,28px);padding:14px 0;display:grid}.ar-ledger li>span:first-child{color:var(--ink);font-size:var(--fs-small);font-weight:500;line-height:1.35}.ar-ledger li>b{color:var(--ink);font-family:var(--font-display);font-variant-numeric:lining-nums tabular-nums;text-align:right;font-size:1.5rem;font-weight:400;line-height:1.1}.ar-ledger li>span:last-child{color:var(--ink-3);font-size:var(--fs-caption);line-height:1.45}.ar-ledger li.is-aside>b{color:var(--ink-3)}.ar-ledger>p{color:var(--ink-3);font-family:var(--font-display);margin:12px 0 0;font-size:.9375rem;font-style:italic;line-height:1.4}.ar-rate{grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin:0 0 1.8rem;display:grid;position:relative}.ar-rate>div{box-shadow:inset 0 0 0 1px #13252e1a, var(--shadow-1);background:#ffffffa8;border-radius:18px;gap:6px;padding:18px 20px 20px;display:grid;position:relative}.ar-rate>div:first-child{box-shadow:inset 0 0 0 1.5px var(--cyan), 0 14px 28px -20px #0a7f9999;background:linear-gradient(#f1fbfd,#e1f4f8)}.ar-rate dt{color:var(--ink-2);align-items:center;gap:10px;font-size:.9375rem;font-weight:500;display:flex}.ar-rate dd{gap:2px;margin:0;display:grid}.ar-rate b{color:var(--ink);font-family:var(--font-display);font-variant-numeric:lining-nums tabular-nums;font-size:clamp(1.4rem,1.1rem + .9vw,1.9rem);font-weight:400;line-height:1.1}.ar-rate dd span{color:var(--ink-3);font-size:.875rem;line-height:1.4}.ar-rate__n{background:var(--cyan);color:#04323d;width:26px;height:26px;font:700 .8125rem/1 var(--font-sans);border-radius:50%;place-items:center;display:grid}.ar-rate>div:not(:first-child) .ar-rate__n{color:var(--ink-3);background:#e1e8ea}.ar-rail{grid-template-columns:repeat(4,minmax(0,1fr));gap:0 18px;margin:2rem 0 0;padding:0;list-style:none;display:grid;position:relative}.ar-rail:before{content:"";background:linear-gradient(90deg, var(--cyan) 0 45%, #0a7f9940 45%);height:2px;position:absolute;top:7px;left:7px;right:7px}.ar-rail li{gap:4px;padding-top:28px;display:grid;position:relative}.ar-rail li:before{content:"";background:var(--cyan);border-radius:50%;width:16px;height:16px;position:absolute;top:0;left:0;box-shadow:0 0 0 4px #01b0cf33}.ar-rail li:nth-child(n+3):before{box-shadow:inset 0 0 0 2px var(--cyan), 0 0 0 4px #01b0cf1a;background:#fff}.ar-rail b{color:var(--cyan-deep);font-family:var(--font-display);font-size:1.1875rem;font-style:italic;font-weight:400}.ar-rail span{color:var(--ink-2);font-size:var(--fs-small);line-height:1.45}.ar-not{margin:0;padding:0;list-style:none;display:grid}.ar-not li{border-block-start:var(--hairline) solid var(--hair);padding:1.3rem 0 1.3rem 2.2rem;position:relative}.ar-not li:before,.ar-not li:after{content:"";background:var(--ink-3);width:14px;height:1.5px;position:absolute;top:2rem;left:2px}.ar-not li:before{transform:rotate(45deg)}.ar-not li:after{transform:rotate(-45deg)}.ar-proof{max-width:44rem}.ar-proof .ar-h2{margin-block-end:1rem}.ar-pair{grid-template-columns:repeat(2,minmax(0,1fr));gap:clamp(28px,5vw,80px);display:grid}.ar-plainlist{margin:0;padding:0;list-style:none}.ar-plainlist li{border-block-start:var(--hairline) solid var(--hair);font-size:var(--fs-body);padding:.95rem 0 .95rem 1.6rem;line-height:1.55;position:relative}.ar-plainlist li:before{content:"";background:var(--cyan);border-radius:50%;width:6px;height:6px;position:absolute;top:1.55rem;left:.15rem;box-shadow:0 0 0 3px #01b0cf24}.ar-plainlist--no li:before{background:var(--ink-4);box-shadow:0 0 0 3px #13252e12}.ar-faq{border-block-start:var(--hairline) solid var(--hair-strong);margin:0;display:grid}.ar-faq>div{border-block-end:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,.8fr) minmax(0,1.2fr);gap:8px clamp(20px,4vw,56px);padding:22px 0;display:grid}.ar-faq dt{color:var(--ink);font-family:var(--font-display);font-size:1.25rem;line-height:1.25}.ar-faq dd{font-size:var(--fs-body);margin:0;line-height:1.62}.ar-links{gap:0;margin:0;padding:0;list-style:none;display:grid}.ar-links li{border-block-start:var(--hairline) solid var(--hair);padding-block:.85rem}.ar-links a{align-items:center;min-height:40px;display:inline-flex}.ar-steps{border-block-start:var(--hairline) solid var(--hair-strong);margin:0;padding:0;list-style:none;display:grid}.ar-steps>li{border-block-end:var(--hairline) solid var(--hair);grid-template-columns:2.4rem minmax(0,1fr);align-items:baseline;gap:4px clamp(16px,3vw,40px);padding:22px 0;display:grid}.ar-steps>li>div{min-width:0}.ar-rows .ar-steps h3{color:var(--ink);font-family:var(--font-display);letter-spacing:-.01em;margin:0 0 .35rem;font-size:1.375rem;font-weight:400;line-height:1.2}.ar-steps p{color:var(--ink-2);font-size:var(--fs-small);line-height:1.6}.ar-code{background:linear-gradient(170deg, var(--paper) 0%, var(--paper-edge) 100%);max-width:100%;color:var(--ink);tab-size:2;border-radius:3px;margin:.9rem 0 0;padding:14px 16px;font:.8125rem/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;overflow-x:auto;box-shadow:inset 0 0 0 1px #13252e14}.ar-code code{font:inherit;white-space:pre}.ar-rows .ar-read-head{color:var(--ink);font-family:var(--font-display);letter-spacing:-.01em;margin:2.4rem 0 .2rem;font-size:1.375rem;font-weight:400;line-height:1.2}.ar-reads{border-block-start:var(--hairline) solid var(--hair-strong);margin:.8rem 0 0;padding:0;list-style:none;display:grid}.ar-reads li{border-block-end:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,.8fr) minmax(0,1.2fr);align-items:baseline;gap:6px clamp(16px,3vw,48px);padding:20px 0;display:grid}.ar-reads b{color:var(--ink);font-family:var(--font-display);font-size:1.25rem;font-weight:400;line-height:1.25}.ar-reads span{color:var(--ink-2);font-size:var(--fs-body);line-height:1.62}.ar-rows .ar-steps__after{color:var(--ink-3);font-size:var(--fs-caption);margin-top:.7rem}.ar-classes{border-block-start:var(--hairline) solid var(--hair-strong);margin:0;padding:0;list-style:none;display:grid}.ar-classes li{border-block-end:var(--hairline) solid var(--hair);grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr) minmax(0,1.2fr);align-items:baseline;gap:4px clamp(16px,3vw,40px);padding:18px 0;display:grid}.ar-classes b{color:var(--ink);font-family:var(--font-display);font-size:1.25rem;font-weight:400;line-height:1.2}.ar-classes span{color:var(--ink-2);font-size:var(--fs-small);line-height:1.55}.ar-classes span:nth-child(2){color:var(--ink-3)}.ar-related{padding-block:clamp(40px,5vw,72px) 0}.ar-related h2{font-size:var(--fs-h3);margin:0 0 1.4rem}.ar-related-list{border-block-start:var(--hairline) solid var(--hair-strong);margin:0;padding:0;list-style:none;display:grid}.ar-related-list li{border-block-end:var(--hairline) solid var(--hair)}.ar-related-list a{color:inherit;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);align-items:baseline;gap:4px clamp(20px,4vw,56px);padding:20px 0;text-decoration:none;display:grid}.ar-related-list a:hover b{color:var(--link)}.ar-related-list b{color:var(--ink);font-family:var(--font-display);transition:color .3s var(--ease);font-size:1.375rem;font-weight:400;line-height:1.2}.ar-related-list span{color:var(--ink-3);font-size:var(--fs-small);line-height:1.55}.ar-related__all{margin:14px 0 0}@media (width<=1100px){.ar-hero{grid-template-columns:minmax(0,1fr)}.ar-hero__fig{margin-inline:0}}@media (width<=900px){.ar-block{grid-template-columns:minmax(0,1fr);gap:1rem}.ar-side{position:static}.ar-pair,.ar-faq>div,.ar-related-list a{grid-template-columns:minmax(0,1fr)}.ar-bill li{grid-template-columns:2rem minmax(0,1fr)}.ar-bill li p{grid-column:2}.ar-classes li,.ar-reads li{grid-template-columns:minmax(0,1fr)}}@media (width<=720px){.ar{--fs-caption:.875rem}}@media (width<=760px){.ar-rail{grid-template-columns:minmax(0,1fr);gap:20px;margin-top:1.6rem;padding-left:4px}.ar-rail:before{background:linear-gradient(180deg, var(--cyan) 0 45%, #0a7f9940 45%);width:2px;height:auto;inset:8px auto 28px 11px}.ar-rail li{padding:0 0 0 34px}.ar-rail li:before{top:2px;left:4px}.ar-ledger li{grid-template-columns:minmax(0,1fr) auto}.ar-ledger li>span:last-child{grid-column:1/-1}.ar-gate li{grid-template-columns:minmax(0,1fr)}}@media (width<=640px){.ar-rate{grid-template-columns:minmax(0,1fr)}.ar-steps>li{grid-template-columns:2rem minmax(0,1fr)}}