:root {
    --bond:       #EDF0EA;   
    --bond-dim:   #DDE2DA;   
    --ink:        #0F1E1C;   
    --graphite:   #5A6462;   
    --verdigris:  #2E6E5E;   
    --oxide:      #A83B27;   

    
    --verdigris-up: #5FA890;
    --oxide-up:     #D9694F;

    --display: 'Archivo', 'Helvetica Neue', Arial, sans-serif;
    --body:    'Source Serif 4', Georgia, 'Times New Roman', serif;
    --data:    'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;

    --measure: 64ch;
    --gutter: clamp(1.25rem, 4vw, 3rem);
    --rail-w: 13rem;
    --masthead-h: 3.75rem;

    --rule: 1px solid var(--bond-dim);
    --rule-ink: 1px solid rgba(15, 30, 28, 0.16);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, p, ul, ol, figure, dl, dd { margin: 0; }
ul[class], ol[class] { list-style: none; padding: 0; }
img, svg { max-width: 100%; display: block; }
button, input, select, textarea { font: inherit; color: inherit; }

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

body {
    background: var(--bond);
    color: var(--ink);
    font-family: var(--body);
    font-size: clamp(1rem, 0.97rem + 0.15vw, 1.0625rem);
    line-height: 1.65;
    font-variant-numeric: tabular-nums;
    -webkit-font-smoothing: antialiased;
}

.d1, .d2, .d3 {
    font-family: var(--display);
    font-weight: 700;
    font-stretch: 70%;
    line-height: 0.94;
    letter-spacing: -0.015em;
    text-wrap: balance;
}
.d1 { font-size: clamp(2.75rem, 1.6rem + 5.6vw, 5.75rem); }
.d2 { font-size: clamp(1.9rem, 1.3rem + 2.6vw, 3.1rem); }
.d3 { font-size: clamp(1.35rem, 1.15rem + 0.9vw, 1.75rem); font-stretch: 78%; line-height: 1.08; }

.lede {
    font-size: clamp(1.0625rem, 1rem + 0.4vw, 1.3125rem);
    line-height: 1.55;
    max-width: 54ch;
}

.d1 + .lede, .d2 + .lede, .d3 + .lede { margin-top: 1.5rem; }

.prose { max-width: var(--measure); }
.prose p + p { margin-top: 1rem; }
.prose strong { font-weight: 600; }

.dim { color: var(--graphite); }

.label {
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--graphite);
}
.mono { font-family: var(--data); font-size: 0.8125rem; letter-spacing: -0.01em; }

a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 0.2em; }
a:hover { text-decoration-thickness: 2px; }

:focus-visible {
    outline: 2px solid var(--ink);
    outline-offset: 3px;
    border-radius: 1px;
}
.on-ink :focus-visible { outline-color: var(--bond); }

.skip {
    position: absolute;
    left: -9999px;
    top: 0;
    background: var(--ink);
    color: var(--bond);
    padding: 0.75rem 1rem;
    z-index: 100;
}
.skip:focus { left: 0; }

.wrap {
    width: min(78rem, 100%);
    margin-inline: auto;
    padding-inline: var(--gutter);
}

.masthead {
    position: sticky;
    top: 0;
    z-index: 40;
    height: var(--masthead-h);
    display: flex;
    align-items: center;
    background: color-mix(in srgb, var(--bond) 88%, transparent);
    backdrop-filter: blur(8px);
    border-bottom: var(--rule);
}
.masthead .wrap { display: flex; align-items: center; gap: 1.5rem; width: min(78rem, 100%); }

.wordmark {
    font-family: var(--display);
    font-weight: 700;
    font-stretch: 66%;
    font-size: 1.0625rem;
    letter-spacing: 0.02em;
    text-transform: uppercase;
    text-decoration: none;
    margin-right: auto;
}

.navlinks { display: flex; align-items: center; gap: 1.5rem; }
.navlinks a {
    font-family: var(--data);
    font-size: 0.75rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--graphite);
}
.navlinks a:hover { color: var(--ink); }
@media (max-width: 33rem) { .navlinks .opt { display: none; } }

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.8125rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    text-decoration: none;
    padding: 0.7rem 1.1rem;
    border: 1px solid var(--ink);
    background: var(--ink);
    color: var(--bond);
    cursor: pointer;
    transition: background 140ms ease, color 140ms ease;
}
.btn:hover { background: transparent; color: var(--ink); }
.btn.ghost { background: transparent; color: var(--ink); }
.btn.ghost:hover { background: var(--ink); color: var(--bond); }

.on-ink .btn { border-color: var(--bond); background: var(--bond); color: var(--ink); }
.on-ink .btn:hover { background: transparent; color: var(--bond); }
.on-ink .btn.ghost { background: transparent; color: var(--bond); }
.on-ink .btn.ghost:hover { background: var(--bond); color: var(--ink); }

.actions { display: flex; flex-wrap: wrap; gap: 0.75rem; }

.band { padding-block: clamp(3.5rem, 7vw, 6.5rem); }
.band--tight { padding-block: clamp(2.5rem, 5vw, 4rem); }
.band--hero { padding-block: clamp(3rem, 6vw, 5rem) clamp(2.5rem, 5vw, 4rem); }
.band + .band { border-top: var(--rule); }

.on-ink {
    background: var(--ink);
    color: var(--bond);
    border-top: 1px solid var(--ink);
}
.on-ink .dim { color: color-mix(in srgb, var(--bond) 62%, var(--ink)); }
.on-ink .label { color: color-mix(in srgb, var(--bond) 62%, var(--ink)); }

.eyebrow { display: block; margin-bottom: 1.25rem; }

.hero-head { max-width: 22ch; }
.hero .lede { margin-top: 1.5rem; }
.hero .actions { margin-top: 2rem; }

.panel {
    margin-top: clamp(2.5rem, 5vw, 3.5rem);
    border: var(--rule);
    background: color-mix(in srgb, var(--bond-dim) 38%, var(--bond));
}
.panel-head {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 0.5rem 1rem;
    padding: 0.7rem 1rem;
    border-bottom: var(--rule);
}
.panel-head .method {
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.75rem;
    letter-spacing: 0.02em;
}
.panel-head .tag {
    margin-left: auto;
    font-family: var(--data);
    font-size: 0.625rem;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--graphite);
    border: var(--rule);
    padding: 0.15rem 0.45rem;
}
.panel-body { padding: 1rem; display: grid; gap: 1.25rem; }

.panel-sub {
    font-family: var(--data);
    font-size: 0.75rem;
    color: var(--graphite);
    margin-bottom: 0.8rem;
    letter-spacing: 0.01em;
}
.panel-sub .id { color: var(--ink); }

.readout { display: grid; gap: 0.35rem; }

.readout-row dd.is-shape { color: var(--graphite); opacity: 0.85; }
.readout-row {
    display: grid;
    grid-template-columns: minmax(7.5rem, auto) 1fr;
    gap: 0.75rem;
    font-family: var(--data);
    font-size: 0.8125rem;
    align-items: baseline;
}
.readout-row dt { color: var(--graphite); letter-spacing: 0.02em; }
.readout-row dd { margin: 0; }

.assert {
    font-family: var(--data);
    font-size: 0.75rem;
    line-height: 1.5;
    color: var(--graphite);
    border-left: 2px solid var(--bond-dim);
    padding-left: 0.75rem;
}

.trail {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.4rem 0.5rem;
}
.chip {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 0.28rem 0.55rem;
    border: 1px solid currentColor;
    color: var(--graphite);
    white-space: nowrap;
}
.chip::before {
    content: '';
    width: 0.4rem;
    height: 0.4rem;
    border-radius: 50%;
    background: currentColor;
    flex: none;
}
.chip[data-state='done']     { color: var(--verdigris); }
.chip[data-state='current']  { color: var(--ink); }
.chip[data-state='pending']  { color: var(--graphite); opacity: 0.55; }
.chip[data-state='bad']      { color: var(--oxide); }
.on-ink .chip[data-state='done'] { color: var(--verdigris-up); }
.on-ink .chip[data-state='current'] { color: var(--bond); }
.on-ink .chip[data-state='bad'] { color: var(--oxide-up); }

.trail .sep { color: var(--bond-dim); font-family: var(--data); font-size: 0.75rem; }
.on-ink .trail .sep { color: color-mix(in srgb, var(--bond) 35%, var(--ink)); }

.trail.is-animating .chip {
    opacity: 0;
    animation: chip-in 380ms cubic-bezier(0.2, 0.7, 0.3, 1) forwards;
    animation-delay: calc(var(--i, 0) * 260ms);
}
@keyframes chip-in {
    from { opacity: 0; transform: translateY(0.3rem); }
    to   { opacity: 1; transform: none; }
}
.trail.is-settled .chip { opacity: 1; animation: none; }

.ladder { display: block; }

.rail { display: none; }

.stage { padding-block: clamp(3rem, 6vw, 5.5rem); }
.stage + .stage { border-top: var(--rule); }

.stage, [id] { scroll-margin-top: calc(var(--masthead-h) + 4.5rem); }
@media (min-width: 64rem) {
    .stage, [id] { scroll-margin-top: calc(var(--masthead-h) + 2rem); }
}
.stage-head { margin-bottom: 1.5rem; }
.stage-head .state {
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--verdigris);
    display: block;
    margin-bottom: 0.85rem;
}
.stage[data-tone='bad'] .stage-head .state { color: var(--oxide); }
.stage-head .d2 { max-width: 20ch; }
.stage .prose { margin-top: 1.25rem; }

@media (min-width: 64rem) {
    .ladder {
        display: grid;
        grid-template-columns: var(--rail-w) minmax(0, 1fr);
        column-gap: clamp(2rem, 5vw, 4.5rem);
        align-items: start;
    }
    .rail {
        display: block;
        position: sticky;
        top: calc(var(--masthead-h) + 3rem);
        padding-block: clamp(3rem, 6vw, 5.5rem);
    }
    .stage { padding-left: 0; }
}

.rail ol,
.railstrip ol { list-style: none; padding: 0; margin: 0; }
.rail ol { display: grid; gap: 0; position: relative; }
.rail li { position: relative; padding-left: 1.5rem; padding-block: 0.6rem; }
.rail li::before {
    content: '';
    position: absolute;
    left: 0.25rem;
    top: 1.05rem;
    width: 0.45rem;
    height: 0.45rem;
    border-radius: 50%;
    border: 1px solid var(--graphite);
    background: var(--bond);
    z-index: 1;
    transition: background 200ms ease, border-color 200ms ease, transform 200ms ease;
}

.rail li:not(:last-child)::after {
    content: '';
    position: absolute;
    left: 0.465rem;
    top: 1.5rem;
    bottom: -0.6rem;
    width: 1px;
    background: var(--bond-dim);
}
.rail a {
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.13em;
    text-decoration: none;
    color: var(--graphite);
    transition: color 200ms ease;
}
.rail li[aria-current='true'] a { color: var(--ink); }
.rail li[aria-current='true']::before {
    background: var(--verdigris);
    border-color: var(--verdigris);
    transform: scale(1.25);
}
.rail li[data-tone='bad'][aria-current='true']::before {
    background: var(--oxide);
    border-color: var(--oxide);
}
.rail li.is-past::before { background: var(--verdigris); border-color: var(--verdigris); }
.rail li.is-past a { color: var(--graphite); }

.railstrip {
    position: sticky;
    top: var(--masthead-h);
    z-index: 30;
    background: color-mix(in srgb, var(--bond) 92%, transparent);
    backdrop-filter: blur(8px);
    border-bottom: var(--rule);
    overflow-x: auto;
    scrollbar-width: none;
}
.railstrip::-webkit-scrollbar { display: none; }
.railstrip ol { display: flex; gap: 0; padding: 0.55rem var(--gutter); }
.railstrip li { flex: none; }
.railstrip a {
    display: block;
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.625rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    text-decoration: none;
    color: var(--graphite);
    padding: 0.2rem 0.6rem;
    border-bottom: 2px solid transparent;
}
.railstrip li[aria-current='true'] a { color: var(--ink); border-bottom-color: var(--verdigris); }
.railstrip li[data-tone='bad'][aria-current='true'] a { border-bottom-color: var(--oxide); }
@media (min-width: 64rem) { .railstrip { display: none; } }

.artifact {
    margin-top: 1.75rem;
    border: var(--rule);
    background: color-mix(in srgb, var(--bond-dim) 38%, var(--bond));
}
.on-ink .artifact {
    border-color: rgba(237, 240, 234, 0.18);
    background: rgba(237, 240, 234, 0.04);
}
.artifact-head {
    padding: 0.55rem 0.9rem;
    border-bottom: var(--rule);
    font-family: var(--data);
    font-size: 0.625rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--graphite);
}
.on-ink .artifact-head {
    border-bottom-color: rgba(237, 240, 234, 0.18);
    color: color-mix(in srgb, var(--bond) 62%, var(--ink));
}
.artifact pre {
    margin: 0;
    padding: 0.9rem;
    overflow-x: auto;
    font-family: var(--data);
    font-size: 0.75rem;
    line-height: 1.7;
    tab-size: 2;
}
.artifact .redacted {
    background: currentColor;
    color: var(--graphite);
    user-select: none;
}

.limit {
    margin-top: 2rem;
    border-left: 3px solid var(--verdigris);
    padding: 0.25rem 0 0.25rem 1.25rem;
    max-width: var(--measure);
}
.on-ink .limit { border-left-color: var(--verdigris-up); }
.limit .label { display: block; margin-bottom: 0.6rem; }

.tablewrap { margin-top: 1.75rem; overflow-x: auto; }
.grid-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.9375rem;
}
.grid-table th, .grid-table td {
    padding: 0.7rem 1rem 0.7rem 0;
    border-bottom: var(--rule);
    vertical-align: top;
}
.on-ink .grid-table th, .on-ink .grid-table td { border-bottom-color: rgba(237, 240, 234, 0.18); }
.grid-table th {
    font-family: var(--data);
    font-weight: 500;
    font-size: 0.625rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--graphite);
    white-space: nowrap;
}
.on-ink .grid-table th { color: color-mix(in srgb, var(--bond) 62%, var(--ink)); }
.grid-table td:last-child, .grid-table th:last-child { padding-right: 0; }

.burden { margin-top: 1.75rem; border-top: var(--rule); max-width: 46ch; }
.on-ink .burden { border-top-color: rgba(237, 240, 234, 0.18); }
.burden li { padding-block: 0.8rem; border-bottom: var(--rule); }
.on-ink .burden li { border-bottom-color: rgba(237, 240, 234, 0.18); }
.answer {
    margin-top: 1.75rem;
    font-family: var(--display);
    font-stretch: 82%;
    font-weight: 700;
    font-size: clamp(1.25rem, 1.05rem + 0.9vw, 1.6rem);
    line-height: 1.15;
    max-width: 24ch;
}

.compare { display: grid; gap: 0; margin-top: 1.75rem; border-top: var(--rule); }
.compare-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.25rem 2rem;
    padding-block: 0.85rem;
    border-bottom: var(--rule);
}
.compare-row .a { color: var(--graphite); }
.compare-row .b { font-weight: 600; }
@media (min-width: 40rem) {
    .compare-row { grid-template-columns: 1fr 1fr; }
}
.on-ink .compare { border-top-color: rgba(237, 240, 234, 0.18); }
.on-ink .compare-row { border-bottom-color: rgba(237, 240, 234, 0.18); }
.on-ink .compare-row .a { color: color-mix(in srgb, var(--bond) 58%, var(--ink)); }

.endpoints { margin-top: 1.75rem; border-top: var(--rule); }
.on-ink .endpoints { border-top-color: rgba(237, 240, 234, 0.18); }
.endpoints li {
    display: grid;
    gap: 0.2rem 1.5rem;
    padding-block: 0.85rem;
    border-bottom: var(--rule);
}
.on-ink .endpoints li { border-bottom-color: rgba(237, 240, 234, 0.18); }
.endpoints code {
    font-family: var(--data);
    font-size: 0.8125rem;
    font-weight: 500;
    letter-spacing: -0.01em;
}
.endpoints .what { color: var(--graphite); font-size: 0.9375rem; }
.on-ink .endpoints .what { color: color-mix(in srgb, var(--bond) 62%, var(--ink)); }
@media (min-width: 44rem) {
    .endpoints li { grid-template-columns: 22rem 1fr; align-items: baseline; }
}

.form { margin-top: 2rem; max-width: 34rem; display: grid; gap: 1.1rem; }
.field { display: grid; gap: 0.4rem; }
.field label { font-family: var(--data); font-size: 0.6875rem; text-transform: uppercase; letter-spacing: 0.12em; }
.field input, .field select, .field textarea {
    background: transparent;
    border: 1px solid rgba(237, 240, 234, 0.3);
    color: inherit;
    padding: 0.65rem 0.75rem;
    font-family: var(--data);
    font-size: 0.875rem;
    width: 100%;
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--bond); }
.field select option { background: var(--ink); color: var(--bond); }
.field .hint { font-family: var(--data); font-size: 0.6875rem; color: color-mix(in srgb, var(--bond) 55%, var(--ink)); }
.field.is-error input { border-color: var(--oxide-up); }
.field .err { font-family: var(--data); font-size: 0.6875rem; color: var(--oxide-up); }

.close-note {
    font-size: clamp(1.25rem, 1.05rem + 0.9vw, 1.75rem);
    line-height: 1.4;
    max-width: 34ch;
    font-weight: 600;
    text-wrap: balance;
}

.foot { border-top: var(--rule); padding-block: 2.5rem; }
.foot-in { display: flex; flex-wrap: wrap; gap: 1rem 2rem; align-items: baseline; }
.foot a { font-family: var(--data); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--graphite); text-decoration: none; }
.foot a:hover { color: var(--ink); }
.foot .who { margin-right: auto; font-family: var(--data); font-size: 0.75rem; color: var(--graphite); }

.foot .who .mantra { display: block; color: var(--ink); letter-spacing: 0.01em; margin-top: 0.3rem; }

.rendered { max-width: 72ch; }
.rendered h1 { font-family: var(--display); font-stretch: 72%; font-weight: 700; font-size: clamp(2rem, 1.5rem + 2vw, 2.75rem); line-height: 1; margin-bottom: 1.5rem; }
.rendered h2 { font-family: var(--display); font-stretch: 78%; font-weight: 700; font-size: 1.5rem; line-height: 1.1; margin-top: 2.75rem; margin-bottom: 0.85rem; padding-top: 1.25rem; border-top: var(--rule); }
.rendered h3 { font-family: var(--display); font-stretch: 84%; font-weight: 600; font-size: 1.125rem; margin-top: 2rem; margin-bottom: 0.5rem; }
.rendered p, .rendered ul, .rendered ol { margin-bottom: 1rem; }
.rendered ul, .rendered ol { padding-left: 1.25rem; }
.rendered li { margin-bottom: 0.35rem; }
.rendered code { font-family: var(--data); font-size: 0.8125rem; background: var(--bond-dim); padding: 0.1em 0.35em; }
.rendered pre { background: var(--bond-dim); padding: 0.9rem; overflow-x: auto; margin-bottom: 1rem; }
.rendered pre code { background: none; padding: 0; }
.rendered table { width: 100%; border-collapse: collapse; margin-bottom: 1.5rem; font-size: 0.9375rem; }
.rendered th, .rendered td { text-align: left; padding: 0.6rem 1rem 0.6rem 0; border-bottom: var(--rule); vertical-align: top; }
.rendered th { font-family: var(--data); font-size: 0.6875rem; text-transform: uppercase; letter-spacing: 0.12em; color: var(--graphite); }

.tableshell { overflow-x: auto; }

.stack-sm > * + * { margin-top: 0.75rem; }
.stack > * + * { margin-top: 1.5rem; }
.stack-lg > * + * { margin-top: 2.5rem; }
.vh { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }