:root {
  --bg: #ffffff; --side: #f7f8fa; --ink: #1a1d23; --ink-2: #5a6170; --ink-3: #8b919c;
  --line: #e7e9ed; --soft: #f5f6f8; --accent: #2456d6; --accent-soft: #edf2fe;
  --mark: #fff3c4; --mark-ink: #6b4e00; --good: #17794a; --bad: #b3362b;
  --add-bg: #e6f5ea; --del-bg: #fcebe8;
  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --serif: "Source Serif 4", "Iowan Old Style", Georgia, serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  box-sizing: border-box;
  padding-top: env(safe-area-inset-top, 0px); padding-bottom: env(safe-area-inset-bottom, 0px);
}
/* White by default, as asked. A dark variant exists only when a viewer forces it. */
:root[data-theme="dark"] {
  --bg: #14171c; --side: #191d23; --ink: #e8eaee; --ink-2: #a9b0bd; --ink-3: #747c8a;
  --line: #2a2f38; --soft: #1c2027; --accent: #8fb0ff; --accent-soft: #1f2a44;
  --mark: #3d3312; --mark-ink: #f1d27c; --good: #6fcf97; --bad: #f09a90;
  --add-bg: #173221; --del-bg: #3a1e1b;
}
*, *::before, *::after { box-sizing: inherit; }
html { height: 100%; scroll-padding-top: calc(env(safe-area-inset-top, 0px) + 60px); }
body { margin: 0; min-height: 100%; background: var(--bg); color: var(--ink); font: 15px/1.6 var(--sans); -webkit-text-size-adjust: 100%; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 3px; }
code, .mono { font-family: var(--mono); font-size: 0.87em; }
code { background: var(--soft); border-radius: 4px; padding: 1px 5px; }
h1, h2, h3, p { margin: 0; }
button, select, textarea, input { font: inherit; color: inherit; }
button { cursor: pointer; }

/* ---- frame: sidebar + content */
.shell { display: grid; grid-template-columns: 280px minmax(0, 1fr); min-height: 100vh; }
#side { background: var(--side); border-right: 1px solid var(--line); padding: 18px 12px 28px; position: sticky; top: env(safe-area-inset-top, 0px); align-self: start; height: 100vh; overflow-y: auto; font-size: 14px; }
.side-project { display: block; font-weight: 600; font-size: 15px; color: var(--ink); padding: 4px 10px 12px; }
.side-label { font-size: 12px; color: var(--ink-3); padding: 0 10px; margin: 6px 0 4px; }
.side-sub { margin-bottom: 10px; }
.side-sub-name { display: block; padding: 5px 10px; border-radius: 6px; color: var(--ink); font-weight: 500; }
.side-sub-name small { color: var(--ink-3); font-weight: 400; margin-left: 6px; }
.side-exp { display: flex; gap: 8px; align-items: baseline; padding: 4px 10px 4px 18px; border-radius: 6px; color: var(--ink-2); line-height: 1.35; }
.side-exp .n { font-family: var(--mono); font-size: 12.5px; color: var(--ink-3); flex: none; }
.side-exp .t { overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; }
.side-sub-name:hover, .side-exp:hover { background: var(--line); text-decoration: none; }
.side-sub-name.active, .side-exp.active { background: var(--accent-soft); color: var(--accent); }
.side-exp.active .n { color: var(--accent); }
.side-foot { display: block; margin: 14px 10px 0; padding: 8px 10px; background: var(--mark); color: var(--mark-ink); border-radius: 6px; font-size: 13px; }
#side ul { list-style: none; margin: 0; padding: 0; }

.bar { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 5; display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 12px 40px; background: var(--bg); border-bottom: 1px solid var(--line); font-size: 13.5px; }
#crumbs { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; min-width: 0; color: var(--ink-3); }
#crumbs .here { color: var(--ink); }
#live { color: var(--ink-3); font-size: 12.5px; white-space: nowrap; }
#live.preview { color: var(--mark-ink); background: var(--mark); padding: 2px 10px; border-radius: 4px; white-space: normal; }
main { max-width: 900px; padding: 34px 40px 96px; }

/* ---- page head */
.kicker { font-size: 13px; color: var(--ink-3); margin-bottom: 6px; display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
h1 { font-size: 27px; line-height: 1.25; font-weight: 600; letter-spacing: -0.012em; max-width: 30em; }
.lede { color: var(--ink-2); margin-top: 8px; max-width: 46em; }
.formula { margin-top: 14px; padding: 12px 18px; background: var(--soft); border-left: 3px solid var(--ink); font-family: var(--serif); font-size: 18px; line-height: 1.9; max-width: 44em; overflow-x: auto; }
.exp-formula { display: block; font-family: var(--serif); font-size: 14.5px; color: var(--ink-2); line-height: 1.7; }
.exp-formula > span { display: block; }
.statusline { margin-top: 10px; display: flex; flex-wrap: wrap; gap: 6px 14px; align-items: center; font-size: 13.5px; color: var(--ink-2); }
.pill { font-size: 12.5px; border-radius: 99px; padding: 1px 10px; background: var(--soft); color: var(--ink-2); }
.pill.running { background: var(--accent-soft); color: var(--accent); }
.pill.failed, .pill.stopped { background: var(--del-bg); color: var(--bad); }
.pill.baseline { background: var(--soft); color: var(--ink-2); }
.pill.best { background: var(--add-bg); color: var(--good); }
section { margin-top: 38px; }
section > h2 { font-size: 17px; font-weight: 600; margin-bottom: 12px; display: flex; flex-wrap: wrap; gap: 6px 12px; align-items: baseline; }
section > h2 small { font-size: 13px; font-weight: 400; color: var(--ink-3); }
section > h2 .right { margin-left: auto; }
.empty { color: var(--ink-3); }

/* ---- headline numbers */
.stats { display: flex; flex-wrap: wrap; gap: 14px 40px; margin-top: 22px; padding: 16px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.stat-label { font-size: 13px; color: var(--ink-2); }
.stat-value { font-size: 26px; font-weight: 600; line-height: 1.25; font-variant-numeric: tabular-nums; }
.stat-base { font-size: 13px; color: var(--ink-3); }
.stat-base.good { color: var(--good); } .stat-base.bad { color: var(--bad); }

/* ---- what changed */
.changes { list-style: none; margin: 0; padding: 0; }
.changes li { padding: 8px 0; border-top: 1px solid var(--line); display: grid; grid-template-columns: minmax(120px, max-content) minmax(0, 1fr); gap: 2px 20px; }
.changes li:first-child { border-top: 0; padding-top: 0; }
.changes .name { font-family: var(--mono); font-size: 13.5px; }
.changes .was { color: var(--ink-3); text-decoration: line-through; }
.changes .now { font-weight: 500; background: var(--mark); color: var(--mark-ink); padding: 0 6px; border-radius: 4px; }
.changes .def { grid-column: 2; color: var(--ink-3); font-size: 13px; }

/* ---- algorithm: pseudocode set like the algorithm block of a paper */
.switch { display: inline-flex; border: 1px solid var(--line); border-radius: 7px; overflow: hidden; font-size: 13px; font-weight: 400; }
.switch button { background: var(--bg); border: 0; padding: 4px 12px; color: var(--ink-2); }
.switch button[aria-pressed="true"] { background: var(--ink); color: var(--bg); }
.algo-def { color: var(--ink-2); max-width: 48em; margin-bottom: 14px; }
.banner { background: var(--mark); color: var(--mark-ink); padding: 8px 12px; border-radius: 6px; font-size: 14px; margin-bottom: 12px; max-width: 52em; }
.pseudo { font-family: var(--serif); font-size: 16.5px; line-height: 1.75; border-top: 2px solid var(--ink); border-bottom: 2px solid var(--ink); padding: 4px 0 8px; max-width: 46em; }
.ps-title { font-weight: 600; padding: 8px 0 6px; border-bottom: 1px solid var(--ink); margin-bottom: 6px; }
.ps-title:not(:first-child) { margin-top: 14px; border-top: 1px solid var(--ink); }
.ps-io { padding: 1px 8px 1px 0; color: var(--ink); }
.ps-io b, .ps-kw { font-weight: 600; }
.ps-line { display: grid; grid-template-columns: 30px minmax(0, 1fr); padding: 1px 8px 1px 0; border-radius: 3px; }
.ps-n { font-family: var(--sans); font-size: 12px; color: var(--ink-3); text-align: right; padding-right: 12px; padding-top: 5px; font-variant-numeric: tabular-nums; }
.ps-t { min-width: 0; overflow-wrap: anywhere; }
.ps-c { color: var(--ink-3); font-style: italic; font-size: 0.92em; margin-left: 14px; white-space: nowrap; }
.ps-c::before { content: "▷ "; font-style: normal; }
.ps-line.add { background: var(--mark); box-shadow: inset 3px 0 0 var(--mark-ink); }
.ps-line.add .ps-n, .ps-line.add .ps-c { color: var(--mark-ink); }
.ps-line.del { color: var(--ink-3); text-decoration: line-through; text-decoration-thickness: 1px; }
.ps-line.del .ps-n { text-decoration: none; }
.pchip { font-family: var(--mono); font-size: 0.78em; background: var(--accent-soft); color: var(--accent); border-radius: 4px; padding: 1px 6px; white-space: nowrap; cursor: help; }
.pchip.unset { background: var(--soft); color: var(--ink-2); }
mjx-container { font-size: 104% !important; }
.pseudo-foot { font-size: 13px; color: var(--ink-3); margin-top: 8px; max-width: 46em; }

.fn { margin-top: 12px; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; max-width: 52em; }
.fn-head { display: flex; justify-content: space-between; gap: 12px; padding: 5px 12px; background: var(--soft); font-size: 12.5px; color: var(--ink-3); font-family: var(--mono); }
.fn-head .tag { color: var(--mark-ink); background: var(--mark); padding: 0 6px; border-radius: 3px; font-family: var(--sans); }
.fn pre { margin: 0; padding: 10px 0; overflow-x: auto; line-height: 1.65; font-family: var(--mono); font-size: 13px; }
.fn pre .l { display: block; padding: 0 14px 0 30px; position: relative; white-space: pre; min-width: max-content; }
.fn pre .l.add { background: var(--add-bg); } .fn pre .l.del { background: var(--del-bg); }
.fn pre .l.add::before { content: "+"; position: absolute; left: 12px; color: var(--good); }
.fn pre .l.del::before { content: "−"; position: absolute; left: 12px; color: var(--bad); }
.param { border-bottom: 1.5px solid var(--accent); cursor: help; }

/* ---- list of experiments, with one bar per experiment for the headline value */
.exps { border-top: 1px solid var(--line); }
.exp-row { display: grid; grid-template-columns: 14px 34px minmax(0, 1fr) 210px; gap: 0 12px; align-items: center; padding: 12px 8px; border-bottom: 1px solid var(--line); color: var(--ink); border-radius: 0; }
.exp-row:hover { background: var(--soft); text-decoration: none; }
.exp-num { font-family: var(--mono); font-size: 13px; color: var(--ink-3); }
.exp-title { font-weight: 500; display: flex; flex-wrap: wrap; gap: 4px 10px; align-items: center; }
.exp-diff { display: block; font-size: 13px; color: var(--ink-3); overflow-wrap: anywhere; }
.exp-metric { display: grid; grid-template-columns: minmax(0, 1fr) 58px; gap: 10px; align-items: center; }
.bar-track { height: 8px; background: var(--soft); border-radius: 4px; overflow: hidden; }
.bar-fill { display: block; height: 100%; border-radius: 4px; }
.exp-metric .val { text-align: right; font-variant-numeric: tabular-nums; font-weight: 500; }
.dot { width: 10px; height: 10px; border-radius: 50%; border: 2px solid; flex: none; display: inline-block; }
.runlink { display: inline-flex; gap: 5px; align-items: center; font-family: var(--mono); font-size: 0.88em; white-space: nowrap; }

/* ---- plots and images */
.toggles { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.toggle { display: inline-flex; align-items: center; gap: 7px; border: 1px solid var(--line); background: var(--bg); border-radius: 99px; padding: 3px 12px 3px 9px; font-size: 13px; text-align: left; }
.toggle[aria-pressed="false"] { color: var(--ink-3); }
.toggle[aria-pressed="false"] .dot { background: transparent !important; }
.views { display: grid; grid-template-columns: repeat(auto-fit, minmax(330px, 1fr)); gap: 28px 32px; }
.view h3 { font-size: 15px; font-weight: 600; }
.view .shows { margin: 2px 0 10px; font-size: 13px; color: var(--ink-2); }
.view.image { grid-column: 1 / -1; }
.plot { position: relative; height: 240px; }
.imgs { display: flex; flex-wrap: wrap; gap: 16px; }
.imgs figure { margin: 0; width: 230px; max-width: 100%; }
.imgs img { width: 100%; height: auto; display: block; border: 1px solid var(--line); border-radius: 6px; background: #fff; }
.imgs figcaption { font-size: 12.5px; color: var(--ink-2); margin-top: 5px; display: flex; gap: 6px; align-items: baseline; }
.slider { display: flex; gap: 10px; align-items: center; font-size: 13px; color: var(--ink-2); margin-bottom: 12px; }
.slider input { width: min(320px, 60vw); accent-color: var(--accent); }

/* ---- notes written by the agent or by you */
.note { padding: 14px 0; border-top: 1px solid var(--line); max-width: 52em; }
.note:first-of-type { border-top: 0; padding-top: 0; }
.note-head { display: flex; flex-wrap: wrap; gap: 4px 12px; align-items: baseline; font-size: 12.5px; color: var(--ink-3); margin-bottom: 3px; }
.note-kind { font-weight: 600; color: var(--ink-2); }
.note-text { overflow-wrap: anywhere; }
.note.conclusion { border: 0; border-left: 3px solid var(--accent); padding: 4px 0 4px 16px; margin-bottom: 16px; }
.note.conclusion .note-text { font-size: 16.5px; line-height: 1.55; }
.note.flash { animation: flash 1.6s ease-out; }
@keyframes flash { from { background: var(--accent-soft); } to { background: transparent; } }
@media (prefers-reduced-motion: reduce) { .note.flash { animation: none; } }
.prev { margin-top: 8px; padding: 6px 10px; background: var(--soft); border-radius: 6px; color: var(--ink-2); font-size: 14px; }
.link { background: none; border: 0; padding: 0; color: var(--accent); font-size: 12.5px; }
.link:hover { text-decoration: underline; }
.link.quiet { color: var(--ink-3); }
.btn { background: var(--bg); border: 1px solid var(--line); border-radius: 7px; padding: 5px 14px; font-size: 14px; }
.btn.primary { background: var(--ink); border-color: var(--ink); color: var(--bg); }
select { background: var(--bg); border: 1px solid var(--line); border-radius: 7px; padding: 4px 8px; max-width: 100%; }
textarea { width: 100%; max-width: 46em; min-height: 64px; display: block; background: var(--bg); border: 1px solid var(--line); border-radius: 7px; padding: 8px 10px; resize: vertical; }
.form { margin-top: 10px; display: grid; gap: 8px; justify-items: start; }
.login { max-width: 30em; display: grid; gap: 14px; justify-items: start; margin-top: 8vh; }
.login input[type="password"] { width: 100%; background: var(--bg); border: 1px solid var(--line); border-radius: 7px; padding: 9px 12px; font-family: var(--mono); font-size: 14px; }
.login .line { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.login .err { color: var(--bad); font-size: 13.5px; }
.form .line { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.form .err { color: var(--bad); font-size: 13px; }
.comment { margin-top: 8px; padding: 7px 12px; border-radius: 6px; font-size: 14px; max-width: 50em; overflow-wrap: anywhere; }
.comment.open { background: var(--mark); color: var(--mark-ink); }
.comment.resolved { background: var(--soft); color: var(--ink-2); }
.comment .cid { font-family: var(--mono); font-size: 12.5px; margin-right: 6px; }

/* ---- project page */
.sub-card { display: block; padding: 18px 0; border-top: 1px solid var(--line); color: var(--ink); }
.sub-card:first-of-type { border-top: 0; padding-top: 0; }
.sub-card .slug { font-family: var(--mono); font-size: 12.5px; color: var(--ink-3); }
.sub-card .q { font-size: 18px; font-weight: 600; line-height: 1.35; margin: 2px 0 6px; max-width: 34em; }
.sub-card .q a { color: var(--ink); }
.sub-card .concl { color: var(--ink-2); max-width: 50em; border-left: 3px solid var(--accent); padding-left: 12px; margin: 8px 0; }
.sub-card .count { font-size: 13px; color: var(--ink-3); }

details { border-top: 1px solid var(--line); padding: 12px 0; }
details:last-of-type { border-bottom: 1px solid var(--line); }
summary { cursor: pointer; font-weight: 500; }
summary small { font-weight: 400; color: var(--ink-3); margin-left: 8px; }
details > *:not(summary) { margin-top: 12px; }
.kv { display: grid; grid-template-columns: minmax(110px, max-content) minmax(0, 1fr); gap: 6px 22px; margin: 0; font-size: 14px; }
.kv dt { color: var(--ink-2); } .kv dd { margin: 0; overflow-wrap: anywhere; }
.kv dd small { display: block; color: var(--ink-3); font-size: 13px; }
.kv .was { color: var(--ink-3); text-decoration: line-through; margin-right: 6px; }
.timeline { list-style: none; margin: 0; padding: 0; font-size: 14px; }
.timeline .day { color: var(--ink-3); font-size: 13px; margin: 12px 0 4px; }
.timeline li.ev { display: grid; grid-template-columns: 48px minmax(0, 1fr); gap: 10px; padding: 2px 0; }
.timeline time { color: var(--ink-3); font-family: var(--mono); font-size: 12.5px; padding-top: 2px; }
.error { background: var(--del-bg); color: var(--bad); padding: 12px 16px; border-radius: 8px; }
#toast { position: fixed; left: 50%; bottom: calc(22px + env(safe-area-inset-bottom, 0px)); transform: translateX(-50%); background: var(--ink); color: var(--bg); padding: 8px 16px; border-radius: 8px; font-size: 14px; opacity: 0; pointer-events: none; transition: opacity 0.2s; max-width: 90vw; }
#toast.on { opacity: 1; }

@media (max-width: 860px) {
  .shell { grid-template-columns: minmax(0, 1fr); }
  #side { position: static; height: auto; max-height: 40vh; border-right: 0; border-bottom: 1px solid var(--line); padding: 12px; }
  .bar { padding: 10px 16px; position: static; }
  main { padding: 22px 16px 70px; }
  h1 { font-size: 22px; }
  .exp-row { grid-template-columns: 14px 34px minmax(0, 1fr); }
  .exp-metric { grid-column: 3; margin-top: 6px; }
  .views { grid-template-columns: minmax(0, 1fr); }
  .pseudo { font-size: 15.5px; }
  .ps-c { white-space: normal; display: block; margin-left: 0; }
}