/* /backtest: the public holdout report. Tokens come from app.css (light and dark). */
.bt-page { --bt-model: var(--chart-line); --bt-hl: var(--chart-mark); --bt-muted: var(--ink-3); --bt-soft: color-mix(in srgb, var(--ink-3) 45%, var(--surface)); }

.bt-hero { padding-bottom: 56px; }
.bt-stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px; margin-top: 40px;
  background: var(--line); border: 1px solid var(--line); border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-2); }
.bt-stat { background: var(--surface); padding: 20px 20px 18px; min-width: 0; }
.bt-stat-label { font: 500 11px/1.3 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-3); }
.bt-stat-value { font: 720 clamp(30px, 3.4vw, 42px)/1.05 var(--display); letter-spacing: -0.03em; color: var(--ink); margin-top: 10px; font-variant-numeric: tabular-nums; }
.bt-stat-value small { font: 500 14px/1 var(--font); color: var(--ink-3); letter-spacing: 0; margin-left: 4px; }
.bt-stat-sub { font-size: 13px; line-height: 1.45; color: var(--ink-2); margin-top: 8px; }
.bt-warehouse { display: flex; flex-wrap: wrap; gap: 6px 18px; margin: 18px 0 0; font: 500 12.5px/1.4 var(--mono); color: var(--ink-3); }
.bt-warehouse span { display: inline-flex; align-items: center; gap: 6px; }
.bt-warehouse svg { width: 14px; height: 14px; }

.bt-findings { list-style: none; counter-reset: f; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.bt-findings li { counter-increment: f; position: relative; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 18px 20px 18px 56px; font-size: 14.5px; line-height: 1.6; color: var(--ink-2); box-shadow: var(--shadow-1); }
.bt-findings li::before { content: counter(f); position: absolute; left: 18px; top: 17px; width: 26px; height: 26px; border-radius: 50%;
  display: grid; place-items: center; font: 600 12px/1 var(--mono); color: var(--copper-ink); background: var(--copper-soft); }
.bt-findings b { color: var(--ink); font-weight: 620; }

.bt-steps { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.bt-step { border-top: 2px solid var(--ink); padding-top: 14px; }
.bt-step-n { font: 600 12px/1 var(--mono); color: var(--copper-ink); }
.bt-step h3 { font-size: 16px; margin: 8px 0 6px; }
.bt-step p { margin: 0; font-size: 14px; line-height: 1.6; color: var(--ink-2); }

.bt-split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); gap: 48px; align-items: center; }
.bt-h2 { font-size: clamp(24px, 2.8vw, 34px); }
.bt-figure { margin: 0; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 18px 18px 14px; box-shadow: var(--shadow-1); min-width: 0; }
.bt-figure figcaption { font-size: 12.5px; color: var(--ink-3); margin-top: 8px; line-height: 1.45; }
.bt-wide { margin-bottom: 18px; }
.bt-chart { position: relative; width: 100%; min-height: 220px; }
.bt-chart svg { display: block; width: 100%; height: auto; overflow: visible; }
.bt-square { max-width: 520px; margin: 0 auto; }
.bt-mini { min-height: 150px; }
.bt-table { margin-top: 18px; }
.bt-note { font-size: 13px; color: var(--ink-3); line-height: 1.6; margin: 14px 0 0; max-width: 640px; }
.bt-grid2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.bt-grid2 .bt-table { margin-top: 0; }
.card-head h3 { font-size: 14px; }

.bt-toggle { display: inline-flex; gap: 2px; padding: 3px; margin-top: 18px; background: var(--surface-2); border: 1px solid var(--line); border-radius: 10px; flex-wrap: wrap; }
.bt-toggle button { appearance: none; border: 0; background: transparent; color: var(--ink-2); font: 500 13px/1 var(--font); padding: 8px 12px; border-radius: 7px; cursor: pointer; }
.bt-toggle button[aria-selected="true"] { background: var(--surface); color: var(--ink); box-shadow: var(--shadow-1); }
.bt-toggle button:focus-visible { box-shadow: var(--focus); }

/* chart marks */
.bt-grid line { stroke: var(--chart-grid); stroke-width: 1; }
.bt-axis text, .bt-label { fill: var(--chart-axis); font: 500 11px/1 var(--font); font-variant-numeric: tabular-nums; }
.bt-label-strong { fill: var(--ink); font: 600 12px/1 var(--font); }
.bt-label-val { fill: var(--ink-2); font: 500 11.5px/1 var(--mono); }
.bt-axis-line { stroke: var(--line-strong); stroke-width: 1; }
.bt-diag { stroke: var(--ink-3); stroke-width: 1.25; stroke-dasharray: 4 4; fill: none; }
.bt-bar { fill: var(--bt-soft); }
.bt-bar.is-model { fill: var(--bt-model); }
.bt-bar.is-hl { fill: var(--bt-hl); }
.bt-bar.is-ceiling { fill: none; stroke: var(--ink-3); stroke-width: 1.25; stroke-dasharray: 3 3; }
.bt-whisker { stroke: var(--ink); stroke-width: 1.5; }
.bt-line { fill: none; stroke: var(--bt-model); stroke-width: 2.25; stroke-linejoin: round; stroke-linecap: round; }
.bt-line.is-base { stroke: var(--ink-3); stroke-dasharray: 5 4; stroke-width: 1.75; }
.bt-line.is-field { stroke: var(--bt-hl); stroke-width: 2; }
.bt-band { fill: var(--chart-band); }
.bt-ci { stroke: var(--ink-2); stroke-width: 1.5; }
.bt-dot { fill: var(--surface); stroke: var(--ink); stroke-width: 2; }
.bt-dot.is-model { fill: var(--bt-model); stroke: var(--surface); }
.bt-dot.is-hl { fill: var(--bt-hl); stroke: var(--surface); stroke-width: 2; }
.bt-dot.is-field { fill: var(--bt-hl); stroke: var(--surface); }
.bt-dot.is-other { fill: var(--ink-3); stroke: var(--surface); stroke-width: 1.5; }
.bt-lowband { fill: var(--chart-field); stroke: var(--chart-field-strip); stroke-width: 1; stroke-dasharray: 2 3; }
.bt-needed { stroke: var(--good); stroke-width: 2; }
.bt-zero { stroke: var(--ink-3); stroke-width: 1; }
.bt-hit { fill: transparent; cursor: pointer; }
.bt-legend { display: flex; flex-wrap: wrap; gap: 6px 16px; margin-top: 10px; font-size: 12.5px; color: var(--ink-2); }
.bt-legend span { display: inline-flex; align-items: center; gap: 6px; }
.bt-legend i { display: inline-block; width: 14px; height: 3px; border-radius: 2px; background: var(--bt-model); }
.bt-legend i.k-dot { width: 9px; height: 9px; border-radius: 50%; background: var(--surface); border: 2px solid var(--ink); }
.bt-legend i.k-base { background: repeating-linear-gradient(90deg, var(--ink-3) 0 5px, transparent 5px 9px); }
.bt-legend i.k-hl { background: var(--bt-hl); }
.bt-legend i.k-band { height: 10px; background: var(--chart-field); border: 1px dashed var(--chart-field-strip); }
.bt-legend i.k-need { background: var(--good); }
.bt-legend i.k-diag { background: repeating-linear-gradient(90deg, var(--ink-3) 0 4px, transparent 4px 8px); }

.bt-tip { position: absolute; z-index: 5; pointer-events: none; background: var(--ink); color: var(--ink-inverse); font: 500 12px/1.45 var(--font);
  padding: 7px 10px; border-radius: 8px; box-shadow: var(--shadow-2); max-width: 260px; opacity: 0; transform: translateY(4px); transition: opacity 0.12s, transform 0.12s; }
.bt-tip.is-on { opacity: 1; transform: none; }
.bt-tip b { font-weight: 650; }

/* reveal on scroll */
.bt-js [data-reveal] { opacity: 0; transform: translateY(14px); transition: opacity 0.6s ease, transform 0.6s ease; }
.bt-js [data-reveal].is-in { opacity: 1; transform: none; }
.bt-grow { transform-box: fill-box; transform-origin: left center; transform: scaleX(0); transition: transform 0.9s cubic-bezier(.2,.7,.2,1); }
.bt-grow-y { transform-box: fill-box; transform-origin: center bottom; transform: scaleY(0); transition: transform 0.9s cubic-bezier(.2,.7,.2,1); }
.is-in .bt-grow, .is-in .bt-grow-y { transform: none; }
.bt-draw { transition: stroke-dashoffset 1.3s cubic-bezier(.3,.6,.2,1); }
.bt-pop { opacity: 0; transition: opacity 0.4s ease 0.5s; }
.is-in .bt-pop { opacity: 1; }
@media (prefers-reduced-motion: reduce) {
  .bt-js [data-reveal], .bt-grow, .bt-grow-y, .bt-pop { opacity: 1 !important; transform: none !important; transition: none !important; }
  .bt-draw { transition: none !important; stroke-dashoffset: 0 !important; }
}

/* replay */
.bt-replay-sum { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-bottom: 22px; }
.bt-replay-sum > div { border-left: 2px solid var(--copper); padding: 2px 0 2px 14px; }
.bt-replay-sum b { display: block; font: 700 26px/1.1 var(--display); letter-spacing: -0.02em; color: var(--ink); }
.bt-replay-sum span { display: block; font-size: 13px; line-height: 1.45; color: var(--ink-2); margin-top: 4px; }
.bt-cards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.bt-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 16px; box-shadow: var(--shadow-1); min-width: 0; display: flex; flex-direction: column; gap: 10px; }
.bt-card h3 { font-size: 14.5px; line-height: 1.35; margin-top: 6px; overflow-wrap: anywhere; }
.bt-card-meta { display: flex; flex-wrap: wrap; gap: 4px 10px; font: 500 11px/1.3 var(--mono); color: var(--ink-3); text-transform: uppercase; letter-spacing: 0.04em; }
.bt-badges { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.bt-dl { margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px 14px; font-size: 13px; }
.bt-dl dt { font: 500 10.5px/1.3 var(--mono); color: var(--ink-3); text-transform: uppercase; letter-spacing: 0.05em; }
.bt-dl dd { margin: 2px 0 0; color: var(--ink); font-variant-numeric: tabular-nums; }
.bt-dl .muted { color: var(--ink-3); font-size: 12px; }

.bt-limits { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px 32px; }
.bt-limits li { font-size: 14.5px; line-height: 1.6; color: var(--ink-2); padding-left: 16px; border-left: 2px solid var(--warn-line); }
.bt-limits b { color: var(--ink); }

.bt-repro { display: flex; align-items: flex-end; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.bt-repro code { white-space: nowrap; }
.bt-cta { display: flex; gap: 10px; flex-wrap: wrap; }

@media (max-width: 1000px) {
  .bt-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .bt-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .bt-split { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .bt-split > .bt-figure:first-child { order: 2; }
  .bt-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .bt-replay-sum { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
  .bt-stats, .bt-findings, .bt-steps, .bt-grid2, .bt-cards, .bt-limits { grid-template-columns: minmax(0, 1fr); }
  .bt-stat { padding: 16px; }
  .bt-findings li { padding: 16px 16px 16px 50px; }
  .bt-findings li::before { left: 14px; }
  .bt-figure { padding: 12px 10px 10px; }
  .bt-replay-sum { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
  .bt-replay-sum b { font-size: 22px; }
  .bt-repro code { white-space: normal; overflow-wrap: anywhere; }
  .bt-cta .btn { flex: 1 1 auto; }
  .bt-hide-sm { display: none; }
}