/* weightsmith: a single, calm article. Serif body, plain sans headings, hairline rules, one accent (teal)
   that appears only inside figures and charts for "the edit". No build step. */

:root {
  --bg: #faf9f5;
  --bg-2: #f2f0e9;
  --ink: #1a1915;
  --ink-2: #3b3a36;
  --muted: #6b6a66;
  --rule: #e6e3da;
  --accent: #147d92;
  --mark-base: #8d8b85; /* charts: unedited / no weight change */
  --mark-other: #3b3a36; /* charts: edits that did not work */
  --grid: #ece9e1;

  --serif: 'Source Serif 4', 'Iowan Old Style', 'Palatino Linotype', Palatino, Georgia, serif;
  --sans: 'Inter', ui-sans-serif, system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --mono: ui-monospace, 'SF Mono', SFMono-Regular, Menlo, Consolas, 'Liberation Mono', monospace;

  --measure: 680px;
  --wide: 800px;
  --gutter: 24px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1a1917;
    --bg-2: #23221f;
    --ink: #ecebe6;
    --ink-2: #d4d2cb;
    --muted: #a3a19b;
    --rule: #34332f;
    --accent: #2aa5bc;
    --mark-base: #87857f;
    --mark-other: #d4d2cb;
    --grid: #2b2a27;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.1875rem; /* 19px */
  line-height: 1.6;
  font-optical-sizing: auto;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img,
video,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  text-decoration-color: color-mix(in srgb, currentColor 35%, transparent);
}

a:hover {
  text-decoration-color: currentColor;
}

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 2px;
  border-radius: 2px;
}

::selection {
  background: color-mix(in srgb, var(--ink) 14%, transparent);
}

h1,
h2,
h3 {
  font-family: var(--sans);
  color: var(--ink);
  text-wrap: balance;
  margin: 0;
}

p,
ul,
ol {
  margin: 0 0 1.1em;
}

p {
  text-wrap: pretty;
}

li + li {
  margin-top: 0.35em;
}

sup {
  font-size: 0.7em;
  line-height: 0;
}

code {
  font-family: var(--mono);
  font-size: 0.82em;
}

.nw {
  white-space: nowrap;
}

.skip {
  position: absolute;
  left: -9999px;
  top: 8px;
  z-index: 10;
  padding: 6px 12px;
  background: var(--ink);
  color: var(--bg);
  font-family: var(--sans);
  font-size: 0.875rem;
}

.skip:focus {
  left: 8px;
}

/* ---------- top bar ---------- */
.bar {
  border-bottom: 1px solid var(--rule);
  font-family: var(--sans);
}

.bar-in {
  width: min(var(--wide), 100% - 2 * var(--gutter));
  margin-inline: auto;
  height: 56px;
  display: flex;
  align-items: center;
  gap: 20px;
}

.wordmark {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.bar nav {
  margin-left: auto;
  display: flex;
  gap: 22px;
}

.bar nav a {
  font-size: 0.9375rem;
  color: var(--muted);
  text-decoration: none;
}

.bar nav a:hover,
.bar nav a[aria-current='page'] {
  color: var(--ink);
}

/* ---------- article column ---------- */
.post > * {
  width: min(var(--measure), 100% - 2 * var(--gutter));
  margin-inline: auto;
}

.post > .wide {
  width: min(var(--wide), 100% - 2 * var(--gutter));
}

/* media inside a section break out of the text column to the wide column, centred on the page */
.post section .wide {
  width: min(var(--wide), 100vw - 2 * var(--gutter));
  margin-left: 50%;
  transform: translateX(-50%);
}

.head {
  padding-top: 36px;
}

.eyebrow {
  margin: 0 0 12px;
  font-family: var(--sans);
  font-size: 0.8125rem;
  line-height: 1.45;
  color: var(--muted);
}

.head h1 {
  font-size: clamp(1.85rem, 1.45rem + 1.3vw, 2.25rem);
  font-weight: 600;
  line-height: 1.13;
  letter-spacing: -0.02em;
}

.dek {
  margin: 12px 0 0;
  font-size: 1.1875rem;
  line-height: 1.45;
  color: var(--ink-2);
}

/* on wide screens the title and dek may run into the right margin of the text column, keeping its left edge */
@media (min-width: 900px) {
  .head:not(.wide) h1,
  .head:not(.wide) .dek {
    margin-right: -90px;
  }
}

.byline {
  margin: 12px 0 0;
  font-family: var(--sans);
  font-size: 0.875rem;
  color: var(--muted);
}

.byline a {
  color: var(--muted);
}

.byline .sep {
  margin: 0 0.45em;
}

.hero {
  margin-top: 24px;
  margin-bottom: 0;
}

.hero video,
.clips video {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  border-radius: 8px;
  border: 1px solid var(--rule);
  background: var(--bg-2);
}

figcaption,
.caption {
  margin-top: 10px;
  font-family: var(--sans);
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--muted);
}

figcaption b {
  color: var(--ink);
  font-weight: 600;
}

.post section {
  margin-top: 3.1rem;
}

.post h2 {
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.012em;
  margin: 0 0 0.8rem;
}

.post h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin: 1.6rem 0 0.4rem;
}

.lede {
  margin-top: 2.2rem;
}

/* every list in the article: a short rule instead of a bullet */
.post section ul {
  padding: 0;
  list-style: none;
}

.post section ul > li {
  position: relative;
  padding-left: 1.1em;
}

.post section ul > li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 0.42em;
  height: 1px;
  background: var(--ink);
}

.note {
  font-family: var(--sans);
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--muted);
}

/* each section opens with its claim */
.claim {
  font-size: 1.3rem;
  line-height: 1.42;
  color: var(--ink);
  letter-spacing: -0.003em;
}

/* the opening video's timeline */
.scrub {
  position: relative;
  margin-top: 12px;
  cursor: ew-resize;
  touch-action: pan-y;
  user-select: none;
  -webkit-user-select: none;
  border-radius: 4px;
}

.scrub.dragging {
  cursor: grabbing;
}

.scrub svg {
  width: 100%;
  overflow: visible;
}

.scrub .tl-name {
  font-family: var(--sans);
  font-size: 12.5px;
  fill: var(--ink-2);
}

.scrub .tl-track {
  fill: var(--grid);
}

.scrub .tl-over {
  fill: var(--bg);
  opacity: 0.6;
}

.scrub .tl-closed.u {
  fill: var(--mark-base);
}

.scrub .tl-closed.e {
  fill: var(--accent);
}

.scrub .tl-x {
  stroke: var(--ink);
  stroke-width: 2;
  stroke-linecap: round;
  fill: none;
}

.scrub .tl-ring {
  fill: var(--bg);
  stroke: var(--accent);
  stroke-width: 2;
}

.scrub .tl-label {
  font-family: var(--sans);
  font-size: 12px;
  fill: var(--muted);
}

.scrub .tl-label.on {
  fill: var(--ink);
}

.scrub .tl-head {
  stroke: var(--ink);
  stroke-width: 1.5;
}

.scrub .tl-dot {
  fill: var(--ink);
  stroke: var(--bg);
  stroke-width: 1.5;
}

.scrub:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 4px;
}

.scrub-readout {
  display: flex;
  flex-wrap: wrap;
  gap: 2px 18px;
  margin: 2px 0 0;
  font-family: var(--sans);
  font-size: 0.8125rem;
  line-height: 1.45;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.scrub-readout .s-step {
  color: var(--ink);
  min-width: 5.2em;
}

.textbtn {
  padding: 0;
  border: 0;
  background: none;
  font: inherit;
  color: var(--ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  text-decoration-color: color-mix(in srgb, currentColor 35%, transparent);
  cursor: pointer;
}

.textbtn:hover {
  text-decoration-color: currentColor;
}

.textbtn[aria-pressed='true'] {
  color: var(--muted);
}

.cmd {
  margin: 0.4rem 0 1.2rem;
  padding: 16px 18px;
  background: var(--bg-2);
  border-radius: 6px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--ink-2);
}

.cmd code {
  font-size: inherit;
}

/* figures (rendered from the paper's plotting code) */
.fig {
  margin: 2rem auto 2.2rem;
}

.fig img {
  margin-inline: auto;
  height: auto;
}

/* each figure opens at full size (it is vector, so it zooms cleanly on a phone) */
.fig-link {
  display: block;
  cursor: zoom-in;
}

.fig figcaption {
  max-width: var(--measure);
  margin-inline: auto;
}

/* diagrams: inline SVG themed by the tokens above (this page and cosmos/); shape and fill, not colour
   alone, carry each outcome */
.dg {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
  font-family: var(--sans);
}

.dg text {
  fill: var(--ink);
  font-size: 13px;
}

.dg .dg-s { font-size: 12.5px; }
.dg .dg-xs { font-size: 11.5px; }
.dg .dg-b { font-weight: 600; }
.dg .dg-h { font-size: 15px; font-weight: 600; }
.dg .dg-mu { fill: var(--muted); }
.dg .dg-acc { fill: var(--accent); }

.dg .dg-blk { fill: var(--bg); stroke: var(--ink-2); stroke-width: 1.25; }
.dg .dg-in { fill: var(--bg-2); stroke: var(--rule); stroke-width: 1; }
.dg .dg-tok { fill: var(--bg); stroke: var(--rule); stroke-width: 1.25; }
.dg .dg-band { fill: color-mix(in srgb, var(--accent) 13%, var(--bg)); stroke: none; }
.dg .dg-acc-b { stroke: var(--accent); stroke-width: 1.5; }
.dg .dg-dash-b { stroke-dasharray: 4 3; }

.dg .dg-ln { fill: none; stroke: var(--muted); stroke-width: 1.25; }
.dg .dg-ln-h { fill: var(--muted); }
.dg .dg-dash { stroke-dasharray: 4 3; }
.dg .dg-acc-ln { fill: none; stroke: var(--accent); stroke-width: 1.5; }
.dg .dg-acc-ln-h { fill: var(--accent); }

.dg .dg-let { fill: var(--bg-2); stroke: var(--ink-2); stroke-width: 1.25; }
.dg .dg-let-t { font-size: 12px; font-weight: 600; }

.dg .dg-o-fix { fill: var(--accent); stroke: var(--accent); stroke-width: 1.5; }
.dg .dg-o-part { fill: var(--bg); stroke: var(--accent); stroke-width: 1.5; }
.dg .dg-o-fill { fill: var(--accent); }
.dg .dg-o-none { fill: var(--bg); stroke: var(--mark-base); stroke-width: 1.5; }
.dg .dg-o-broke { fill: var(--mark-other); stroke: var(--mark-other); stroke-width: 1.5; }
.dg .dg-o-x { stroke: var(--bg); stroke-width: 1.75; stroke-linecap: round; }

.dg-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin: 0 0 12px;
  padding: 0;
  list-style: none;
  font-family: var(--sans);
  font-size: 0.8125rem;
  color: var(--ink-2);
}

.post section .dg-legend > li {
  display: flex;
  align-items: center;
  gap: 7px;
  padding-left: 0;
}

.post section .dg-legend > li::before {
  content: none;
}

.dg-legend .dg-key {
  width: 15px;
  height: 15px;
  flex: none;
}

.dg-blog .dg-panel {
  max-width: 340px;
  margin-inline: auto;
}

.dg-blog .dg-legend {
  justify-content: center;
}

.fig-n {
  color: var(--ink);
  font-weight: 600;
}

.eq {
  margin: 1.4rem 0 1.5rem;
  text-align: center;
  font-size: 1.3rem;
  line-height: 1.4;
  overflow-x: auto;
}

.eq i {
  font-style: italic;
}

.eq .lam {
  display: block;
  margin-top: 4px;
  font-size: 0.95rem;
  color: var(--muted);
}

.clips {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin: 1.8rem auto 1.4rem;
}

.clips figure {
  margin: 0;
}

.post table.mde {
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.9375rem;
  margin: 0.4rem 0 1.4rem;
  font-variant-numeric: tabular-nums;
}

.mde th,
.mde td {
  padding: 6px 28px 6px 0;
  border-bottom: 1px solid var(--rule);
  text-align: left;
}

.mde th {
  font-weight: 500;
  color: var(--muted);
}

.code {
  position: relative;
  margin: 0.4rem 0 0.6rem;
}

.code pre {
  margin: 0;
  padding: 16px 18px;
  background: var(--bg-2);
  border-radius: 6px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--ink-2);
}

.copy {
  position: absolute;
  top: 8px;
  right: 8px;
  padding: 3px 9px;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--bg);
  color: var(--muted);
  font-family: var(--sans);
  font-size: 0.75rem;
  cursor: pointer;
}

.copy:hover {
  color: var(--ink);
}

.copied {
  min-height: 1.4em;
  margin: 0;
}

.end {
  margin-top: 3.4rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--rule);
}

.foot {
  margin-top: 4rem;
  border-top: 1px solid var(--rule);
  font-family: var(--sans);
  font-size: 0.8125rem;
  color: var(--muted);
}

.foot-in {
  width: min(var(--wide), 100% - 2 * var(--gutter));
  margin-inline: auto;
  padding: 22px 0 40px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.foot a {
  color: var(--muted);
}

/* ---------- explorer ---------- */
.filters {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 10px 16px;
  margin-top: 1.6rem;
  font-family: var(--sans);
}

.filters label {
  display: grid;
  gap: 4px;
  font-size: 0.8125rem;
  color: var(--muted);
  max-width: 100%;
}

.filters select {
  font: inherit;
  font-size: 0.9375rem;
  color: var(--ink);
  background: var(--bg);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 6px 8px;
  max-width: 100%;
}

.count {
  margin: 0 0 4px auto;
  font-size: 0.875rem;
  color: var(--muted);
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin: 1.4rem 0 0.6rem;
  padding: 0;
  list-style: none;
  font-family: var(--sans);
  font-size: 0.8125rem;
  color: var(--muted);
}

.legend li {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin: 0;
}

.lg {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--mark-other);
  flex: none;
}

.lg.fix {
  background: var(--accent);
}

.lg.held {
  border-radius: 1px;
  transform: rotate(45deg) scale(0.9);
  background: var(--accent);
}

.lg.astra {
  border-radius: 1px;
}

.lg.change {
  background: transparent;
  box-shadow: inset 0 0 0 2px var(--mark-other);
}

.lg.noise {
  background: var(--mark-base);
}

.chart-box {
  position: relative;
}

#chart {
  width: 100%;
  overflow: visible;
}

#chart text {
  font-family: var(--sans);
  fill: var(--ink);
}

#chart .t-task {
  font-size: 13px;
  font-weight: 500;
}

#chart .t-label,
#chart .t-count {
  font-size: 11.5px;
  fill: var(--muted);
}

#chart .t-count {
  font-variant-numeric: tabular-nums;
}

#chart .t-group {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
  fill: var(--muted);
}

#chart .t-axis {
  font-size: 11px;
  fill: var(--muted);
}

#chart .grid {
  stroke: var(--grid);
  stroke-width: 1;
}

#chart .zero {
  stroke: var(--muted);
  stroke-width: 1;
  opacity: 0.7;
}

#chart .hit {
  fill: transparent;
}

#chart .row {
  outline: none;
}

#chart .row:hover .hit,
#chart .row.active .hit,
#chart .row:focus-visible .hit {
  fill: color-mix(in srgb, var(--ink) 5%, transparent);
}

#chart .row:focus-visible .hit {
  stroke: var(--ink);
  stroke-width: 1;
}

#chart .ring {
  stroke: var(--bg);
  stroke-width: 4;
  paint-order: stroke;
}

#chart .m-held,
#chart .m-fix {
  fill: var(--accent);
}

#chart .m-claude,
#chart .m-astra {
  fill: var(--mark-other);
}

#chart .m-noise {
  fill: var(--mark-base);
}

#chart .m-pad {
  fill: var(--bg);
}

#chart .m-change {
  fill: var(--bg);
  stroke: var(--mark-other);
  stroke-width: 2;
}

#chart .ci {
  stroke-width: 2.5;
  stroke-linecap: round;
  opacity: 0.35;
  stroke: var(--mark-other);
}

#chart .ci-held,
#chart .ci-fix {
  stroke: var(--accent);
  opacity: 0.45;
}

#chart .ci-noise {
  stroke: var(--mark-base);
}

.tscroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-top: 2rem;
}

.dtable {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.8125rem;
  line-height: 1.4;
  font-variant-numeric: tabular-nums;
}

.dtable caption {
  caption-side: top;
  text-align: left;
  padding-bottom: 8px;
  font-size: 0.875rem;
  color: var(--muted);
}

.dtable th,
.dtable td {
  padding: 7px 10px;
  text-align: right;
  vertical-align: baseline;
  border-bottom: 1px solid var(--rule);
}

.dtable th:nth-child(-n + 4),
.dtable td:nth-child(-n + 4) {
  text-align: left;
}

.dtable th:first-child,
.dtable td:first-child {
  padding-left: 0;
}

.dtable thead th {
  font-weight: 500;
  color: var(--muted);
  white-space: nowrap;
}

.dtable tbody tr.active {
  background: color-mix(in srgb, var(--ink) 5%, transparent);
}

.dtable .d {
  font-weight: 600;
  white-space: nowrap;
}

.dtable .ci {
  display: block;
  font-weight: 400;
  font-size: 0.75rem;
  color: var(--muted);
}

/* one tooltip, used by the explorer chart */
.tooltip {
  position: fixed;
  z-index: 20;
  left: 0;
  top: 0;
  pointer-events: none;
  max-width: min(320px, calc(100vw - 24px));
  padding: 8px 10px;
  border-radius: 4px;
  background: var(--ink);
  color: var(--bg);
  font-family: var(--sans);
  font-size: 0.78rem;
  line-height: 1.45;
  opacity: 0;
}

.tooltip.show {
  opacity: 1;
}

.tooltip .tt-v {
  font-weight: 600;
}

.tooltip .tt-s {
  opacity: 0.75;
}

/* ---------- small screens ---------- */
@media (max-width: 700px) {
  :root {
    --gutter: 16px;
  }

  body {
    font-size: 1.125rem;
  }

  .head {
    padding-top: 28px;
  }

  .dek {
    font-size: 1.125rem;
  }

  .clips {
    grid-template-columns: minmax(0, 1fr);
    gap: 18px;
  }

  .bar nav {
    gap: 16px;
  }
}

@media print {
  .bar,
  .copy,
  .tooltip {
    display: none !important;
  }
}

/* breathing room between a table and the paragraph that follows it */
.tscroll + p { margin-top: 1.5em; }