:root{--paper:#F6F1E6;--paper2:#ECE5D6;--card:#FFFDF8;--ink:#16201D;--ink2:#46524E;--rule:#D8CFBD;--green:#123B32;--green2:#1D5446;--pink:#FF186B;--link:#9C0F45;--max:1180px;
--serif:Georgia,Cambria,"Times New Roman",serif;--sans:system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;--mono:Consolas,ui-monospace,"Cascadia Mono","Liberation Mono",monospace}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
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img{max-width:100%;height:auto;display:block}
a{color:var(--link);text-underline-offset:3px}a:hover{color:var(--ink)}
:focus-visible{outline:3px solid var(--pink);outline-offset:2px}
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.ukp-crumbs a{display:inline-flex;align-items:center;min-height:44px;min-width:44px}
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.ukp-strip b{font-weight:700;color:var(--green);text-transform:uppercase;letter-spacing:.06em;font-size:12px;margin-right:6px}
h1,h2,h3{font-family:var(--serif);line-height:1.18;color:var(--ink)}
h1{font-size:clamp(31px,4.2vw,48px);margin:18px 0 10px;max-width:26ch;font-weight:700}
h2{font-size:clamp(23px,2.5vw,31px);margin:0 0 14px;font-weight:700;display:flex;align-items:baseline;gap:12px;flex-wrap:wrap}
h3{font-size:20px;margin:22px 0 8px}
.ukp-ref{font:600 13px var(--mono);color:var(--green2);border:1px solid var(--green2);border-radius:3px;padding:1px 6px;letter-spacing:.04em}
.ukp-lede{font-size:19px;max-width:66ch;color:var(--ink2);margin:0 0 16px}
.ukp-hero{padding:14px 0 6px}
.ukp-slipform{display:flex;max-width:820px;margin:6px 0 12px;border:2px solid var(--green);border-radius:4px;overflow:hidden;background:var(--card);box-shadow:4px 4px 0 var(--paper2)}
.ukp-slipform label{position:absolute;left:-999px}
.ukp-slipform input{flex:1;min-width:0;border:0;padding:0 16px;font:18px var(--sans);min-height:60px;color:var(--ink);background:var(--card)}
.ukp-slipform input:focus{outline:none;box-shadow:inset 0 0 0 3px var(--pink)}
.ukp-slipform button{border:0;background:var(--pink);color:#16201D;font:700 18px var(--serif);padding:0 28px;min-height:60px;cursor:pointer}
.ukp-slipform button:hover{background:var(--green);color:#fff}
.ukp-sub{display:flex;flex-wrap:wrap;gap:0 22px;font-size:15px;margin:0 0 8px;padding:0;list-style:none}
.ukp-sub a{display:inline-flex;align-items:center;min-height:44px;color:var(--ink);text-decoration-color:var(--green2);text-decoration-thickness:2px}
.ukp-wall{padding:22px 0 18px;border-top:2px solid var(--green)}
.ukp-wall>h2{margin-bottom:6px}
.ukp-wall>p{max-width:70ch;color:var(--ink2);margin:0 0 16px}
.ukp-stubs{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:14px}
.ukp-stubs>li{min-width:0}
.ukp-stub{display:flex;height:100%;background:var(--card);border:1px solid var(--rule);border-left:2px dashed var(--green2);border-radius:3px;text-decoration:none;color:var(--ink);overflow:hidden}
.ukp-stub:hover{border-color:var(--green)}
.ukp-stub img{width:42%;aspect-ratio:4/3;object-fit:cover;background:#fff;flex:none;align-self:center}
.ukp-stub__body{padding:10px 12px;display:flex;flex-direction:column;gap:3px;min-width:0}
.ukp-stub b{font:700 17px/1.2 var(--serif)}
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.ukp-copy{max-width:76ch}.ukp-copy p{margin:0 0 14px}.ukp-copy ul,.ukp-copy ol{padding-left:22px;margin:0 0 14px}.ukp-copy li{margin:0 0 6px}
.ukp-after{margin-top:18px}
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.ukp-split--flip{grid-template-columns:minmax(0,55fr) minmax(0,45fr)}.ukp-split--flip .ukp-fig{order:-1}
.ukp-split .ukp-copy{min-width:0}
.ukp-fig{margin:0;display:flex;flex-direction:column;min-width:0;background:var(--card);border:1px solid var(--rule);border-radius:3px;overflow:hidden}
.ukp-split .ukp-fig img{width:100%;height:auto}
.ukp-split .ukp-fig figcaption{margin-top:auto}
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.ukp-fig--wide{max-width:720px;margin:20px 0}
.ukp-fig--wide img{width:100%;height:auto}
.ukp-tablewrap{overflow-x:auto;margin:14px 0;max-width:76ch}
.ukp-table{border-collapse:collapse;width:100%;font-size:15px;background:var(--card)}
.ukp-table caption{text-align:left;font-size:14px;color:var(--ink2);padding:0 0 8px}
.ukp-table th,.ukp-table td{border:1px solid var(--rule);padding:8px 10px;text-align:left;vertical-align:top}
.ukp-table th{background:var(--green);color:#fff;font-weight:600}
.ukp-table.ukp-num td:not(:first-child){font-family:var(--mono);white-space:nowrap;font-variant-numeric:tabular-nums}
.ukp-table a{display:inline-flex;align-items:center;min-height:44px;min-width:44px}
.ukp-note{background:var(--card);border:1px solid var(--rule);border-left:5px solid var(--green2);padding:12px 16px;margin:14px 0;max-width:76ch}
.ukp-note p{margin:0}
.ukp-faq{max-width:76ch}.ukp-faq details{border-bottom:1px dashed var(--rule)}
.ukp-faq summary{cursor:pointer;font:700 18px/1.4 var(--serif);padding:11px 0;min-height:44px}
.ukp-faq details>div{padding:0 0 10px}
.ukp-calc{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:28px;align-items:start;background:var(--card);border:2px solid var(--green);border-radius:4px;padding:22px;margin:16px 0}
.ukp-calc fieldset{border:0;padding:0;margin:0 0 10px;min-width:0}
.ukp-calc legend{font:700 18px var(--serif);margin:0 0 6px}
.ukp-calc label{display:block;font-size:14px;margin:8px 0 3px;color:var(--ink2)}
.ukp-calc input,.ukp-calc select{width:100%;min-height:44px;border:1px solid var(--ink2);border-radius:3px;padding:0 10px;font:16px var(--mono);background:#fff;color:var(--ink)}
.ukp-out{background:var(--green);color:#F1EBDD;border-radius:3px;padding:16px 18px}
.ukp-out table{width:100%;border-collapse:collapse;font-size:14px}
.ukp-out th,.ukp-out td{padding:6px 4px;border-bottom:1px solid #2E6556;text-align:left;vertical-align:top}
.ukp-out td.n{font:700 16px var(--mono);color:#FFD7E5;text-align:right;white-space:nowrap}
.ukp-small{font-size:14px;color:var(--ink2);margin:6px 0 0}.ukp-out th{font-weight:500;color:#F1EBDD}
.ukp-out p{font-size:14px;color:#E2DACB;margin:12px 0 0}
.ukp-foot{background:var(--green);color:#EDE6D6;margin-top:30px}
.ukp-foot__in{max-width:var(--max);margin:0 auto;padding:30px 20px;display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:24px}
.ukp-foot a{color:#FFC6DA}.ukp-foot__name{font:700 19px var(--serif);color:#fff}
.ukp-foot__logo{width:120px;height:auto}
.ukp-foot__links{list-style:none;margin:0;padding:0}.ukp-foot__links a{display:inline-flex;align-items:center;min-height:44px}
.ukp-foot__small{grid-column:1 / -1;font-size:13px;color:#D3CAB8;margin:0}
@media (max-width:900px){.ukp-split,.ukp-calc{grid-template-columns:minmax(0,1fr)}.ukp-split--flip .ukp-fig{order:0}
.ukp-foot__in{grid-template-columns:minmax(0,1fr)}}
@media (max-width:600px){.ukp-nav a{padding:0 7px;font-size:14px}.ukp-brand span{font-size:15px}
.ukp-stubs{grid-template-columns:minmax(0,1fr);gap:10px}.ukp-strip{font-size:12px}}
@media (max-width:480px){body{font-size:16px}.ukp-slipform button{padding:0 16px}}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important;scroll-behavior:auto!important}}
@media (prefers-color-scheme:dark){:root{--paper:#0E1F1A;--paper2:#16302A;--card:#132822;--ink:#EEE8DA;--ink2:#C7C0B0;--rule:#2D4A42;--link:#FF9CC0;--green2:#8FD1BC}
.ukp-top,.ukp-stub,.ukp-fig,.ukp-calc,.ukp-table,.ukp-slipform,.ukp-slipform input,.ukp-note{background:var(--card);color:var(--ink)}
.ukp-calc input,.ukp-calc select{background:#0B1A16;color:var(--ink)}
.ukp-fig img,.ukp-stub img{background:#fff}.ukp-slipform button{color:#16201D}.ukp-slipform button:hover{background:#EEE8DA;color:#16201D}
.ukp-table th{background:#0A1612}.ukp-foot,.ukp-out{background:#081310}.ukp-strip b{color:var(--green2)}.ukp-top{border-bottom-color:var(--green2)}}

/* UK payments notebook: cool paper, slate ink and mint controls. */
:root{--paper:#edf4f3;--paper2:#dceae7;--card:#fff;--ink:#23393f;--ink2:#4c6065;--rule:#b8ceca;--green:#263f46;--green2:#315d57;--pink:#a5e4d0;--link:#285950;--sans:"Trebuchet MS","Segoe UI",Arial,sans-serif;--max:1180px}
body{font-size:17px}a:hover{color:var(--ink)}:focus-visible{outline:3px solid #137863;outline-offset:3px}input::placeholder{color:var(--ink2);opacity:1}
.ukp-top{border-bottom:1px solid var(--rule)}.ukp-top__in{padding-top:13px;padding-bottom:13px}.ukp-brand span{max-width:230px}.ukp-brand em{display:block;font:500 12px/1.8 var(--mono);text-transform:uppercase;letter-spacing:.09em}
.ukp-nav a{font:600 14px var(--sans);padding:0 10px}.ukp-nav a[aria-current]{box-shadow:inset 0 -2px 0 var(--green2)}
.ukp-hero{padding:29px 0 17px}.ukp-kicker{font:600 12px/1.7 var(--mono);text-transform:uppercase;letter-spacing:.1em;color:var(--green2);margin:0 0 12px}
h1{font-size:clamp(32px,4vw,48px);max-width:28ch;letter-spacing:-.035em}h2{letter-spacing:-.02em}h3{line-height:1.3}
.ukp-lede{max-width:65ch}.ukp-slipform{max-width:880px;border-radius:0;box-shadow:5px 5px 0 var(--paper2)}.ukp-slipform button{background:var(--pink);color:#163d35;font-family:var(--sans)}.ukp-search-status{color:#8b362a;font-size:14px;margin:0}.ukp-search-status:empty{display:none}
.ukp-stubs{grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.ukp-stub{border:1px solid var(--rule);border-left:3px solid #75b49f;border-radius:0}.ukp-stub img{width:39%;aspect-ratio:1;object-fit:contain}.ukp-stub__body{padding:10px;gap:6px}.ukp-stub b{font:700 16px/1.2 var(--sans)}.ukp-stub__body>span{font-size:13px}.ukp-stub i{font-size:10px}.ukp-stub:hover{background:#f7fffc;transform:translateY(-1px)}
.ukp-wall{border-top:1px solid var(--green);padding-top:24px}.ukp-sec{padding:38px 0;border-bottom:1px solid var(--rule)}.ukp-copy{max-width:78ch}.ukp-copy p{line-height:1.7}.ukp-split{gap:28px;grid-template-columns:minmax(0,1fr) minmax(0,1.1fr);align-items:start}
.ukp-fig{border-radius:0;background:var(--card);width:100%;max-width:100%}.ukp-fig>a{display:block}.ukp-fig img{width:100%;height:auto;object-fit:contain}.ukp-fig figcaption{background:var(--card);font-size:13px;padding:12px 15px}.ukp-fig figcaption a{display:inline-flex;min-height:32px;align-items:center}.ukp-tutorial{margin:22px 0 5px;max-width:1140px}.ukp-source-stack{max-width:960px}.ukp-source-stack .ukp-fig{margin-top:20px}.ukp-fig--wide{max-width:960px}
.ukp-definition{display:grid;grid-template-columns:1fr 1fr;gap:36px}.ukp-definition>div{padding-left:20px;border-left:2px solid #83b7a8}.ukp-definition h3{margin:0 0 10px}.ukp-definition p{margin:0 0 14px}
.ukp-money{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:start}.ukp-receipt{background:var(--card);padding:22px 24px;border-top:5px solid var(--green);border-bottom:2px dashed var(--rule);font-size:16px}.ukp-receipt dl{margin:0 0 20px}.ukp-receipt dl>div{padding:13px 0;border-bottom:1px solid var(--rule)}.ukp-receipt dt{font:700 14px var(--mono);color:var(--green2)}.ukp-receipt dd{margin:5px 0 0}.ukp-receipt>a{font-weight:700;display:inline-block;min-height:32px}
.ukp-stepnav{display:grid;grid-template-columns:repeat(3,1fr);border-top:1px solid var(--rule);border-left:1px solid var(--rule);margin:25px 0}.ukp-stepnav a{padding:12px;min-height:44px;font-size:14px;border-right:1px solid var(--rule);border-bottom:1px solid var(--rule)}.ukp-actions{max-width:78ch;padding-left:23px}.ukp-actions li{padding:7px 0}.ukp-glossary{display:grid;grid-template-columns:1fr 1fr;gap:0 30px;max-width:900px}.ukp-glossary>div{border-bottom:1px solid var(--rule);padding:14px 0}.ukp-glossary dt{font-weight:700}.ukp-glossary dd{margin:5px 0 0}
.ukp-pagehead{padding:10px 0}.ukp-map{columns:2;padding-left:22px}.ukp-map li{break-inside:avoid}.ukp-map a{display:inline-flex;min-height:44px;align-items:center}.ukp-note{border-radius:0;border-left-width:3px;background:var(--card);max-width:900px}.ukp-tablewrap{max-width:100%}.ukp-table th,.ukp-table td{overflow-wrap:anywhere}.ukp-table th[scope="row"]{max-width:220px}.ukp-calc{grid-template-columns:minmax(0,1fr) minmax(0,1.15fr);border-radius:0;gap:24px}.ukp-calc caption{text-align:left;font:700 20px var(--serif);margin-bottom:16px}.ukp-out{border-radius:0;background:var(--green);position:sticky;top:20px}.ukp-out table{table-layout:fixed}.ukp-out th:first-child{width:52%}.ukp-out td.n{white-space:normal;overflow-wrap:anywhere;color:#bdeedc;line-height:1.7;font-size:16px}.ukp-out th,.ukp-out td{border-color:#59716d}.ukp-out p{color:#e6efed}.ukp-reset{min-height:44px;border:1px solid var(--green2);background:var(--paper);color:var(--ink);padding:8px 15px;font:600 14px var(--sans);cursor:pointer}.ukp-calc [aria-invalid="true"]{border:2px solid #ae3d2c}.ukp-calc input,.ukp-calc select{border-radius:0}
.ukp-foot{background:#263f46}.ukp-foot a{color:#b6e5d5}.ukp-foot__links{columns:2;column-gap:24px}.ukp-foot__links li{break-inside:avoid}.ukp-foot__links a{font-size:14px;line-height:1.4;min-width:44px}.ukp-foot__in{grid-template-columns:1fr 1fr;gap:40px}.ukp-foot__small{color:#d5e1de}.ukp-menu{display:none}
.ukp-action-link,.ukp-copy>a,.ukp-definition a,.ukp-receipt>a{display:inline-flex;align-items:center;min-height:44px;min-width:44px}.ukp-fig figcaption a{min-height:44px;min-width:44px}
@media(max-width:1000px){.ukp-stubs{grid-template-columns:repeat(3,minmax(0,1fr))}.ukp-top__in{gap:8px}.ukp-nav{width:100%}.ukp-brand span{max-width:none}.ukp-nav a{padding:0 12px}}
@media(max-width:800px){.ukp-stubs{grid-template-columns:repeat(2,minmax(0,1fr))}.ukp-split,.ukp-money,.ukp-calc{grid-template-columns:1fr}.ukp-definition{gap:22px}.ukp-stepnav{grid-template-columns:repeat(2,1fr)}.ukp-out{position:static}.ukp-foot__in{grid-template-columns:1fr}.ukp-split .ukp-fig{max-width:680px}.ukp-main{padding-left:20px;padding-right:20px}}
@media(max-width:600px){.ukp-top__in{padding:12px 18px}.ukp-brand img{width:72px}.ukp-brand span{font-size:15px}.ukp-brand em{font-size:10px}.ukp-menu{display:block;margin-left:auto;min-width:56px;min-height:44px;background:var(--card);border:1px solid var(--rule);color:var(--ink);font:600 14px var(--sans)}.ukp-js .ukp-nav{display:none}.ukp-js .ukp-nav.ukp-open{display:block}.ukp-nav ul{display:grid;grid-template-columns:1fr 1fr;border-top:1px solid var(--rule);padding-top:10px}.ukp-nav a{width:100%}.ukp-main{padding-left:18px;padding-right:18px}.ukp-hero{padding-top:23px}.ukp-kicker{font-size:10px}h1{font-size:34px}.ukp-lede{font-size:17px}.ukp-slipform input{font-size:16px;padding:0 10px;min-height:54px}.ukp-slipform button{font-size:16px;min-height:54px;padding:0 18px}.ukp-sub{gap:0 17px;font-size:13px}.ukp-stubs{grid-template-columns:1fr;gap:8px}.ukp-stub img{width:88px;height:88px}.ukp-stub__body{flex:1}.ukp-stub b{font-size:16px}.ukp-stub i{margin-top:0}.ukp-definition,.ukp-glossary{grid-template-columns:1fr}.ukp-definition>div{padding-left:16px}.ukp-sec{padding:28px 0}.ukp-money{gap:20px}.ukp-receipt{padding:18px}.ukp-calc{padding:14px;gap:20px}.ukp-out{padding:14px 12px}.ukp-out td.n{font-size:14px}.ukp-stepnav{grid-template-columns:1fr}.ukp-foot__in{padding:25px 18px}.ukp-map{columns:1}.ukp-table{font-size:14px}.ukp-table th,.ukp-table td{padding:8px}.ukp-fig figcaption{font-size:12px}.ukp-slipform{box-shadow:3px 3px 0 var(--paper2)}}
@media(prefers-color-scheme:dark){:root{--paper:#17262b;--paper2:#293e43;--card:#20343a;--ink:#eef5f2;--ink2:#c6d6d1;--rule:#53706d;--green:#263f46;--green2:#b5e7d6;--link:#b5e7d6}.ukp-stub:hover{background:#2c474d}.ukp-calc input,.ukp-calc select{background:#14272c;color:var(--ink)}.ukp-foot,.ukp-out{background:#10292e}.ukp-receipt{border-top-color:#91c5b5}.ukp-slipform button:hover{background:#e2f8f0}.ukp-search-status{color:#ffb8a7}.ukp-calc [aria-invalid="true"]{border-color:#ffb8a7}:focus-visible{outline-color:#b5e7d6}}