[hidden] { display: none !important; }
:root, :root[data-theme] {
  --paper: var(--gray-20);
  --raised: var(--gray-10);
  --ink: var(--gray-830);
  --accent: var(--blue-550);
  --warn: var(--yellow-300);
  --shadow: color-mix(in oklch, var(--ink) 20%, transparent);
  --ink-2: color-mix(in oklch, var(--ink) 72%, var(--paper));
  --ink-3: color-mix(in oklch, var(--ink) 58%, var(--paper));
  --ink-4: color-mix(in oklch, var(--ink) 28%, var(--paper));
  --line: color-mix(in oklch, var(--ink) 11%, var(--paper));
  --line-soft: color-mix(in oklch, var(--ink) 6.5%, var(--paper));
  --fill: color-mix(in oklch, var(--ink) 3.5%, var(--paper));
  --lv-rest: .66; --bar-h: 56px; --gutter: 24px;
  --page-gutter: clamp(20px, 4vw, 56px);
  --f-ui: var(--font);
  --f-display: var(--font);
  --f-mono: var(--font-mono);
  --ease-out: cubic-bezier(.2, 0, 0, 1);
  --spring: linear(0, 0.0499 3.8%, 0.1593 7.7%, 0.2881 11.5%, 0.4151 15.4%, 0.5297 19.2%, 0.628 23.1%, 0.7096 26.9%, 0.7756 30.8%, 0.8281 34.6%, 0.8693 38.5%, 0.9012 42.3%, 0.9257 46.2%, 0.9444 50%, 0.9585 53.8%, 0.9692 57.7%, 0.9772 61.5%, 0.9832 65.4%, 0.9876 69.2%, 0.9909 73.1%, 0.9933 76.9%, 0.9951 80.8%, 0.9964 84.6%, 0.9974 88.5%, 0.9981 92.3%, 0.9986 96.2%, 1);
  color-scheme: light;
}
:root[data-theme="dark"] { --paper: var(--gray-880); --raised: var(--gray-840); --ink: var(--gray-60); --accent: var(--blue-250); --warn: var(--yellow-200); --shadow: color-mix(in srgb, var(--gray-900) 55%, transparent); color-scheme: dark; }
*, *::before, *::after { box-sizing: border-box; }
html { scroll-padding-top: 96px; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--font); font-size: 15px; line-height: 1.5; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; font-optical-sizing: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 8px; }

/* =====================================================================
   One bar, one DOM. Every layout below only changes grid areas and
   positions, so switching layouts can morph each element into place.
   ===================================================================== */
.bar { position: fixed; inset: 0 0 auto 0; z-index: 50; pointer-events: none; }
.bar-in {
  position: relative; display: grid; align-items: center; height: var(--bar-h); padding-inline: var(--gutter);
  background: var(--paper); box-shadow: 0 1px 0 var(--line); pointer-events: auto;
  padding-top: env(safe-area-inset-top, 0px);
}
.b-nav, .c3 { display: contents; }
.menu-a, .menu-b { display: flex; list-style: none; margin: 0; padding: 0; }
.b-mark { grid-area: mark; justify-self: start; font: 450 20px/1 var(--font); font-variation-settings: "opsz" 24; letter-spacing: -0.022em; padding: 6px 6px 9px; margin-left: -6px; border-radius: 8px; white-space: nowrap; }
.menu-a { grid-area: ma; } .menu-b { grid-area: mb; }
.actions { grid-area: act; justify-self: end; display: flex; align-items: center; gap: 4px; }
.b-crumb { grid-area: crumb; display: none; align-items: center; gap: 8px; font: 12px/16px var(--font-mono); color: var(--ink-3); white-space: nowrap; }
.b-crumb i { font-style: normal; color: var(--ink-4); }
.b-crumb b { font-weight: 400; color: var(--ink); font-variant-numeric: tabular-nums; }
.b-meta { grid-area: meta; display: none; font: 12px/16px var(--font-mono); color: var(--ink-3); white-space: nowrap; }
.b-more { grid-area: more; display: none; }
.top {
  position: relative; display: inline-flex; align-items: center; height: 40px; padding: 0 12px; border-radius: 8px; white-space: nowrap;
  font-size: 13px; font-weight: 450; letter-spacing: 0em;
  color: color-mix(in oklch, var(--ink) calc(var(--lv, var(--lv-rest)) * 100%), var(--paper));
  font-variation-settings: "GRAD" var(--grad, 0);
}
.link { display: inline-flex; align-items: center; height: 40px; padding: 0 12px; border-radius: 8px; font-size: 13px; color: var(--ink-2); white-space: nowrap; }
.link:is(:hover, [data-hover]) { color: var(--ink); }
.btn { display: inline-flex; align-items: center; justify-content: center; height: 32px; padding: 0 13px; border: 0; border-radius: 8px; font: 500 13px/1 var(--font); white-space: nowrap; cursor: default; }
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-quiet { box-shadow: inset 0 0 0 1px var(--line); background: transparent; }
.cta-short { display: none; }
.idx-sub { display: none; list-style: none; margin: 0; padding: 0; }
.menu-toggle { display: none; }
@supports (corner-shape: squircle) { .btn, .top, .link, .b-mark { corner-shape: squircle; border-radius: 12px; } }


/* ---------- 11  Letterbox ---------- */
.bar[data-layout="letterbox"] .bar-in { grid-template-columns: auto 1fr auto auto; grid-template-areas: "mark . ma mb"; z-index: 1; }
.bar[data-layout="letterbox"] .menu-b { margin-right: -12px; }
.bar[data-layout="letterbox"] .actions { position: fixed; right: 24px; bottom: calc(10px + env(safe-area-inset-bottom, 0px)); pointer-events: auto; z-index: 2; }
.bar[data-layout="letterbox"] .b-crumb { display: inline-flex; position: fixed; left: 24px; bottom: calc(20px + env(safe-area-inset-bottom, 0px)); z-index: 2; pointer-events: auto; }
.b-bottom { display: none; position: fixed; left: 0; right: 0; bottom: 0; height: calc(52px + env(safe-area-inset-bottom, 0px)); padding-bottom: env(safe-area-inset-bottom, 0px); background: var(--paper); box-shadow: 0 -1px 0 var(--line); align-items: center; justify-content: center; gap: 14px; pointer-events: auto; font: 12px/16px var(--font-mono); color: var(--ink-3); }
.bar[data-layout="letterbox"] .b-bottom { display: flex; }
.bb-track { position: relative; width: 220px; height: 1px; background: var(--line); }
.bb-track i { position: absolute; left: 0; top: -0.5px; height: 2px; width: 100%; transform-origin: left center; transform: scaleX(var(--p, 0)); background: var(--ink); }
.bb-time { font-variant-numeric: tabular-nums; min-width: 88px; }

/* ---------- mobile: every study collapses to the same small bar ---------- */
.bar[data-layout="mobile"] .bar-in { grid-template-columns: 1fr auto; grid-template-areas: "mark act"; padding-inline: 16px; }
.bar[data-layout="mobile"] .menu-a, .bar[data-layout="mobile"] .menu-b, .bar[data-layout="mobile"] .b-signin { display: none; }
.bar[data-layout="mobile"] .menu-toggle { display: inline-flex; }

/* =====================================================================
   The page underneath, with room made for each layout
   ===================================================================== */
.page { padding-top: var(--bar-h); transition: padding 0s; }
body[data-layout="letterbox"] .page { padding-bottom: 52px; }
.wrap { max-width: 1280px; margin-inline: auto; padding-inline: var(--page-gutter); }
.hero { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); column-gap: 24px; row-gap: 40px; padding-block: clamp(40px, 7vh, 88px) 64px; align-items: start; }
.hero-text { grid-column: 1 / span 5; padding-top: 12px; }
.hero-fig { grid-column: 7 / span 6; min-width: 0; }
.eyebrow { margin: 0; font: 12px/16px var(--font-mono); color: var(--ink-3); }
h1 { margin: 18px 0 20px; font: 400 clamp(38px, 4.5vw, 68px)/1.02 var(--f-display); letter-spacing: -0.022em; font-variation-settings: "opsz" 72; text-wrap: balance; }
.lede { margin: 0; max-width: 42ch; font-size: 17px; line-height: 1.56; color: var(--ink-2); }
.cta { display: flex; gap: 10px; margin-top: 30px; }
.cta .btn { height: 38px; padding: 0 16px; }
.fig { background: var(--raised); border: 1px solid var(--line); border-radius: 12px; overflow: hidden; font-size: 13px; }
.fig-head { display: flex; justify-content: space-between; gap: 12px; padding: 12px 16px; font: 12px/16px var(--font-mono); color: var(--ink-3); border-bottom: 1px solid var(--line); }
.wf-body { padding: 8px 0 12px; }
.wf-row { display: grid; grid-template-columns: 40% minmax(0, 1fr) 46px; align-items: center; gap: 12px; height: 27px; padding: 0 16px; }
.wf-name { font: 12px/16px var(--font-mono); color: var(--ink-2); padding-left: calc(var(--d) * 14px); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.wf-track { position: relative; height: 100%; background: linear-gradient(90deg, var(--line-soft) 1px, transparent 1px) 0 0 / calc(100% / 3) 100%; }
.wf-bar { position: absolute; top: 50%; height: 9px; margin-top: -4.5px; border-radius: 4px; background: var(--ink-4); }
.wf-bar.m { background: var(--accent); }
.wf-bar.w { background: repeating-linear-gradient(135deg, color-mix(in oklch, var(--warn) 70%, var(--raised)) 0 3px, color-mix(in oklch, var(--warn) 30%, var(--raised)) 3px 6px); }
.wf-dur { font: 11px var(--font-mono); color: var(--ink-3); text-align: right; font-variant-numeric: tabular-nums; }
.article { max-width: 680px; padding-block: 24px 380px; }
.article section { padding-top: 40px; border-top: 1px solid var(--line); margin-top: 40px; }
.article h2 { margin: 0 0 12px; font: 400 32px/1.15 var(--font); letter-spacing: -0.015em; }
.article p { margin: 0 0 14px; color: var(--ink-2); font-size: 15px; line-height: 1.65; max-width: 64ch; }
@media (max-width: 960px) { .hero-text, .hero-fig { grid-column: 1 / -1; } }
@media (max-width: 760px) { h1 { font-size: 40px; } .wf-row { grid-template-columns: 46% minmax(0, 1fr); } .wf-dur { display: none; } }

.toast { position: fixed; z-index: 61; left: 50%; top: 50%; transform: translate(-50%, -6px); opacity: 0; padding: 8px 12px; border-radius: 8px; background: var(--ink); color: var(--paper); font: 12px var(--font-mono); pointer-events: none; transition: opacity 180ms, transform 300ms var(--ease-out); white-space: nowrap; }
.toast[data-on] { opacity: 1; transform: translate(-50%, 0); }
@media (prefers-reduced-motion: reduce) { .toast { transition: opacity 180ms; } }