/* ═══════════════════════════════════════════════════════════════
   Blackrack Labs — editorial mission-control skin
   Deep-space navy + cyan signal. Blueprint grid atmosphere,
   mono annotations, framed diagram figures with a zoom lightbox.
   Fonts: Chakra Petch (display) · Geist (body) · Geist Mono (tech)
   ═══════════════════════════════════════════════════════════════ */

@import url("https://fonts.googleapis.com/css2?family=Chakra+Petch:wght@400;500;600;700&family=Geist:wght@400;500;600&family=Geist+Mono:wght@400;500;600&display=swap");

/* ── Tokens ───────────────────────────────────────────────────── */
:root {
  --bk-bg: #03050a;
  --bk-surface: #0a1222;
  --bk-surface2: #101c30;
  --bk-ink: #e8f4ff;
  --bk-muted: #88a5c2;
  --bk-dim: #53697f;
  --bk-border: #12374a;
  --bk-border2: #176887;
  --bk-cyan: #00c6ff;
  --bk-cyan-bright: #8de8ff;
  --bk-electric: #0072ff;
  --bk-font-display: "Chakra Petch", sans-serif;
  --bk-font-body: "Geist", sans-serif;
  --bk-font-mono: "Geist Mono", monospace;
}

/* Light scheme overrides */
[data-md-color-scheme="default"] {
  --bk-bg: #f2f7fc;
  --bk-surface: #ffffff;
  --bk-surface2: #e4eef6;
  --bk-ink: #0a1626;
  --bk-muted: #40566e;
  --bk-dim: #6b8299;
  --bk-border: #cbdce8;
  --bk-border2: #9cc3d8;
  --bk-cyan: #0072ff;
  --bk-cyan-bright: #0062d9;
  --bk-electric: #0057b8;
}

/* ── Material native tokens ───────────────────────────────────── */
[data-md-color-scheme="slate"] {
  --md-default-bg-color: var(--bk-bg);
  --md-default-fg-color: var(--bk-ink);
  --md-default-fg-color--light: var(--bk-muted);
  --md-default-fg-color--lighter: var(--bk-dim);
  --md-default-fg-color--lightest: rgba(136, 165, 194, 0.16);
  --md-primary-fg-color: var(--bk-cyan);
  --md-typeset-a-color: var(--bk-cyan-bright);
  --md-code-bg-color: var(--bk-surface);
  --md-code-fg-color: var(--bk-ink);
  --md-admonition-bg-color: var(--bk-surface);
  --md-footer-bg-color: #020409;
  --md-footer-fg-color: var(--bk-muted);
  --md-typeset-table-color: rgba(136, 165, 194, 0.16);
  --md-typeset-table-color--light: rgba(136, 165, 194, 0.08);
  --md-code-hl-color: rgba(0, 198, 255, 0.12);
  --md-typeset-kbd-border-color: var(--bk-border2);
  --md-typeset-kbd-color: var(--bk-surface2);
}

[data-md-color-scheme="default"] {
  --md-default-bg-color: var(--bk-bg);
  --md-default-fg-color: var(--bk-ink);
  --md-default-fg-color--light: var(--bk-muted);
  --md-default-fg-color--lighter: var(--bk-dim);
  --md-default-fg-color--lightest: rgba(64, 86, 110, 0.12);
  --md-primary-fg-color: var(--bk-cyan);
  --md-typeset-a-color: var(--bk-cyan-bright);
  --md-code-bg-color: var(--bk-surface2);
  --md-code-fg-color: var(--bk-ink);
  --md-admonition-bg-color: var(--bk-surface);
  --md-footer-bg-color: #e7eef6;
  --md-footer-fg-color: var(--bk-muted);
  --md-typeset-table-color: rgba(64, 86, 110, 0.18);
  --md-typeset-table-color--light: rgba(64, 86, 110, 0.08);
  --md-code-hl-color: rgba(0, 114, 255, 0.12);
}

/* ── Body atmosphere: blueprint grid + glows ──────────────────── */
body {
  font-family: var(--bk-font-body);
  letter-spacing: -0.005em;
  background-color: var(--bk-bg);
  background-image:
    radial-gradient(900px 480px at 12% -8%, rgba(0, 198, 255, 0.10), transparent 60%),
    radial-gradient(800px 420px at 96% 8%, rgba(0, 114, 255, 0.10), transparent 55%),
    linear-gradient(rgba(0, 198, 255, 0.028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 198, 255, 0.028) 1px, transparent 1px);
  background-size: auto, auto, 44px 44px, 44px 44px;
  background-attachment: fixed;
}

[data-md-color-scheme="default"] body {
  background-image:
    radial-gradient(900px 480px at 12% -8%, rgba(0, 114, 255, 0.06), transparent 60%),
    radial-gradient(800px 420px at 96% 8%, rgba(0, 198, 255, 0.06), transparent 55%),
    linear-gradient(rgba(0, 114, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 114, 255, 0.035) 1px, transparent 1px);
  background-size: auto, auto, 44px 44px, 44px 44px;
  background-attachment: fixed;
}

::selection {
  background: rgba(0, 198, 255, 0.35);
  color: #e8f4ff;
}
[data-md-color-scheme="default"] ::selection {
  background: rgba(0, 114, 255, 0.22);
  color: #0a1626;
}

/* Scrollbars */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--bk-border); border-radius: 8px; }
::-webkit-scrollbar-thumb:hover { background: var(--bk-border2); }

:focus-visible {
  outline: 2px solid var(--bk-cyan);
  outline-offset: 2px;
}

/* ── Header / nav ─────────────────────────────────────────────── */
.md-header {
  background: rgba(3, 5, 10, 0.78);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(0, 198, 255, 0.16);
  box-shadow: 0 1px 24px rgba(0, 114, 255, 0.08);
}
[data-md-color-scheme="default"] .md-header {
  background: rgba(242, 247, 252, 0.82);
  border-bottom: 1px solid rgba(0, 114, 255, 0.18);
}

.md-header__title {
  font-family: var(--bk-font-display);
  font-weight: 600;
  letter-spacing: 0.02em;
  font-size: 1rem;
}
.md-header__button:hover { color: var(--bk-cyan-bright); }
.md-search__form {
  background-color: var(--bk-surface);
  border: 1px solid var(--bk-border);
  border-radius: 8px;
}
.md-search__form:hover { border-color: var(--bk-border2); }

.md-tabs {
  background: transparent;
  border-bottom: 1px solid rgba(136, 165, 194, 0.10);
}
.md-tabs__link {
  font-family: var(--bk-font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--bk-muted);
}
.md-tabs__link--active, .md-tabs__link:hover { color: var(--bk-cyan-bright); }
.md-tabs__item--active {
  box-shadow: 0 2px 0 0 var(--bk-cyan);
}

.md-nav__link { color: var(--bk-muted); }
.md-nav__link--active, .md-nav__link:hover { color: var(--bk-cyan-bright); }
.md-nav__item .md-nav__link--active { font-weight: 600; }

.md-footer { border-top: 1px solid rgba(0, 198, 255, 0.14); }
.md-footer__link { color: var(--bk-muted); }
.md-footer__link:hover { color: var(--bk-cyan-bright); }

.md-top {
  color: var(--bk-cyan-bright);
  border: 1px solid var(--bk-border2);
  background: var(--bk-surface);
  border-radius: 8px;
}
.md-top:hover { border-color: var(--bk-cyan); }

/* ── Typography ───────────────────────────────────────────────── */
.md-typeset h1, .md-typeset h2, .md-typeset h3, .md-typeset h4 {
  font-family: var(--bk-font-display);
  letter-spacing: -0.01em;
  color: var(--bk-ink);
}

.md-typeset h1 {
  font-weight: 600;
  font-size: 2rem;
  line-height: 1.15;
}
.md-typeset h1::after {
  content: "";
  display: block;
  width: 96px;
  height: 3px;
  margin-top: 0.7rem;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--bk-cyan), transparent);
}

.md-typeset h2 {
  font-weight: 600;
  font-size: 1.35rem;
  border-bottom: 1px solid rgba(136, 165, 194, 0.14);
  padding-bottom: 0.45rem;
}
.md-typeset h2::before {
  content: "";
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 0.55rem;
  border-radius: 2px;
  background: linear-gradient(135deg, var(--bk-cyan), var(--bk-electric));
  vertical-align: middle;
}
.md-typeset h3 { font-weight: 600; font-size: 1.08rem; color: var(--bk-cyan-bright); }

.md-typeset a {
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(0, 198, 255, 0.35);
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}
.md-typeset a:hover { color: var(--bk-ink); text-decoration-color: var(--bk-cyan); }

/* Code */
.md-typeset code {
  font-family: var(--bk-font-mono);
  font-size: 0.78em;
  background: var(--bk-surface2);
  border: 1px solid var(--bk-border);
  border-radius: 4px;
  padding: 0.1em 0.35em;
}
.md-typeset pre > code {
  background: var(--bk-surface);
  border: 1px solid var(--bk-border);
  border-left: 3px solid var(--bk-cyan);
  border-radius: 8px;
  font-size: 0.76em;
}
.md-typeset .highlight .hll { background-color: var(--md-code-hl-color); }

/* Tables */
.md-typeset table:not([class]) {
  border: 1px solid var(--bk-border);
  border-radius: 8px;
  overflow: hidden;
  font-size: 0.82em;
}
.md-typeset table:not([class]) th {
  font-family: var(--bk-font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  background: var(--bk-surface2);
  color: var(--bk-cyan-bright);
}
.md-typeset table:not([class]) tr:nth-child(even) { background: rgba(136, 165, 194, 0.05); }

/* Admonitions */
.md-typeset .admonition, .md-typeset details {
  border: 1px solid var(--bk-border);
  border-left-width: 3px;
  border-radius: 8px;
  background: var(--bk-surface);
  box-shadow: none;
  font-size: 0.86em;
}
.md-typeset .admonition-title, .md-typeset summary {
  font-family: var(--bk-font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* Buttons */
.md-typeset .md-button {
  font-family: var(--bk-font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  border: 1px solid var(--bk-border2);
  border-radius: 8px;
  color: var(--bk-cyan-bright);
  background: rgba(0, 114, 255, 0.06);
  padding: 0.5em 1.1em;
  transition: border-color 0.2s ease, background 0.2s ease;
}
.md-typeset .md-button:hover {
  border-color: var(--bk-cyan);
  background: rgba(0, 198, 255, 0.10);
  text-decoration: none;
  color: var(--bk-cyan-bright);
}
.md-typeset .md-button--primary {
  background: var(--bk-cyan);
  border-color: var(--bk-cyan);
  color: #03050a;
  font-weight: 600;
}
.md-typeset .md-button--primary:hover {
  background: var(--bk-cyan-bright);
  color: #03050a;
}

/* Tags */
.md-tag {
  font-family: var(--bk-font-mono);
  border: 1px solid var(--bk-border2);
  color: var(--bk-cyan-bright);
  background: rgba(0, 114, 255, 0.07);
  border-radius: 999px;
}

/* ── Diagram figures (dark cards in both schemes) ─────────────── */
.bk-diagram {
  margin: 1.5rem 0;
  background: #0a1222;
  border: 1px solid #12374a;
  border-radius: 10px;
  padding: 12px 12px 0;
  box-shadow: inset 0 0 48px rgba(0, 198, 255, 0.035);
  position: relative;
}
.bk-diagram::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, #00c6ff, transparent 55%);
  border-radius: 10px 10px 0 0;
  opacity: 0.6;
}
.bk-diagram img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 6px;
}
.bk-diagram figcaption {
  font-family: var(--bk-font-mono);
  font-size: 0.72rem;
  color: #88a5c2;
  padding: 0.7rem 0.3rem 1rem;
  letter-spacing: 0.01em;
}

/* Slightly widen big diagrams on large screens */
@media (min-width: 1220px) {
  .bk-diagram { margin-inline: -2.5rem; }
}

/* ── Zoom button ──────────────────────────────────────────────── */
.bk-zoom-button {
  position: absolute;
  top: 14px;
  right: 14px;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  font-family: var(--bk-font-mono);
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #8de8ff;
  background: rgba(10, 18, 34, 0.88);
  border: 1px solid #176887;
  border-radius: 6px;
  padding: 0.42em 0.8em;
  cursor: zoom-in;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: border-color 0.18s ease, background 0.18s ease;
}
.bk-zoom-button svg {
  width: 12px;
  height: 12px;
  fill: none;
  stroke: #00c6ff;
  stroke-width: 2;
  stroke-linecap: round;
}
.bk-zoom-button:hover {
  border-color: #00c6ff;
  background: rgba(0, 114, 255, 0.22);
}

/* ── Lightbox ─────────────────────────────────────────────────── */
.bk-lightbox {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2.5rem;
  background: rgba(3, 5, 10, 0.93);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.22s ease, visibility 0.22s ease;
}
.bk-lightbox.open {
  opacity: 1;
  visibility: visible;
}
.bk-lightbox figure {
  margin: 0;
  max-width: min(94vw, 1400px);
  max-height: 92vh;
  display: flex;
  flex-direction: column;
  background: #0a1222;
  border: 1px solid #176887;
  border-radius: 12px;
  padding: 12px 12px 0;
  box-shadow: 0 0 80px rgba(0, 114, 255, 0.22);
}
.bk-lightbox img {
  display: block;
  max-width: 100%;
  max-height: 82vh;
  object-fit: contain;
  border-radius: 8px;
}
.bk-lightbox figcaption {
  font-family: var(--bk-font-mono);
  font-size: 0.75rem;
  color: #88a5c2;
  padding: 0.9rem 0.4rem 1.1rem;
  text-align: center;
}
.bk-lightbox-close {
  position: absolute;
  top: 1.2rem;
  right: 1.2rem;
  width: 42px;
  height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.05rem;
  color: #8de8ff;
  background: rgba(10, 18, 34, 0.9);
  border: 1px solid #176887;
  border-radius: 8px;
  cursor: pointer;
  transition: border-color 0.18s ease, background 0.18s ease;
}
.bk-lightbox-close:hover {
  border-color: #00c6ff;
  background: rgba(0, 114, 255, 0.22);
}

/* Landing: hero (quiet, editorial) */
.bk-hero {
  margin: 1rem 0 2.2rem;
}
.bk-hero h1::after { display: none; }
.bk-lede {
  color: var(--bk-muted);
  font-size: 1.05rem;
  line-height: 1.7;
  margin: 0 0 1.4rem;
  max-width: 62ch;
}

/* CTA button rows need breathing room between buttons */
.bk-hero .md-button,
.bk-cta .md-button {
  margin: 0.3rem 0.6rem 0.3rem 0;
}
.bk-cta {
  margin: 1rem 0;
}

/* ── Landing: stats ───────────────────────────────────────────── */
.bk-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--bk-border);
  border-radius: 10px;
  margin: 1.2rem 0 1.6rem;
  background: var(--bk-surface);
  overflow: hidden;
}
@media (max-width: 760px) { .bk-stats { grid-template-columns: repeat(2, 1fr); } }
.bk-stat {
  padding: 0.9rem 1.1rem;
  border-right: 1px solid var(--bk-border);
}
.bk-stat:last-child { border-right: none; }
.bk-stat .bk-num {
  font-family: var(--bk-font-display);
  font-weight: 600;
  font-size: 1.45rem;
  color: var(--bk-cyan);
  display: block;
  line-height: 1.1;
}
.bk-stat .bk-lbl {
  font-family: var(--bk-font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.04em;
  color: var(--bk-muted);
  display: block;
  margin-top: 0.3rem;
}

/* ── Landing: chips ───────────────────────────────────────────── */
.bk-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin: 0.8rem 0 1.8rem;
}
.bk-chip {
  font-family: var(--bk-font-mono);
  font-size: 0.7rem;
  border: 1px solid var(--bk-border);
  border-radius: 999px;
  padding: 0.28em 0.85em;
  color: var(--bk-muted);
  background: transparent;
  transition: border-color 0.18s ease, color 0.18s ease;
}
.bk-chip:hover {
  border-color: var(--bk-border2);
  color: var(--bk-cyan-bright);
}

/* ── Landing: pillar cards (calm grid) ────────────────────────── */
.bk-section { margin: 2.4rem 0 1.2rem; }
.bk-section h2 {
  font-family: var(--bk-font-display);
  font-weight: 600;
  font-size: 1.5rem;
  color: var(--bk-ink);
  margin: 0.4rem 0 1rem;
}
.bk-section h2::before { display: none; }
.bk-section h2::after {
  content: "";
  display: block;
  width: 72px;
  height: 3px;
  margin-top: 0.55rem;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--bk-cyan), transparent);
}

.bk-pillars {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.8rem;
}
@media (max-width: 1000px) { .bk-pillars { grid-template-columns: 1fr; } }

.bk-pillar {
  display: block;
  background: var(--bk-surface);
  border: 1px solid var(--bk-border);
  border-radius: 10px;
  padding: 1.1rem 1.15rem 1.2rem;
  transition: border-color 0.2s ease, background 0.2s ease;
}
.bk-pillar:hover {
  border-color: var(--bk-border2);
  background: var(--bk-surface2);
  text-decoration: none;
}
.bk-pidx {
  font-family: var(--bk-font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  color: var(--bk-dim);
  display: block;
  margin-bottom: 0.6rem;
}
.bk-pillar h3 {
  font-family: var(--bk-font-display);
  font-weight: 600;
  font-size: 1rem;
  color: var(--bk-ink);
  margin: 0 0 0.4rem;
}
.bk-pillar p {
  color: var(--bk-muted);
  font-size: 0.84rem;
  line-height: 1.55;
  margin: 0;
}

/* ── Landing: read cards ──────────────────────────────────────── */
.bk-reads {
  display: grid;
  grid-template-columns: 1.2fr 1fr 0.9fr;
  gap: 0.8rem;
}
@media (max-width: 1000px) { .bk-reads { grid-template-columns: 1fr; } }
.bk-read {
  display: block;
  background: var(--bk-surface);
  border: 1px solid var(--bk-border);
  border-left: 3px solid var(--bk-border2);
  border-radius: 10px;
  padding: 1rem 1.1rem;
  transition: border-color 0.2s ease;
}
.bk-read:hover {
  border-left-color: var(--bk-cyan);
  text-decoration: none;
}
.bk-read h3 {
  font-family: var(--bk-font-display);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--bk-cyan-bright);
  margin: 0 0 0.35rem;
}
.bk-read p { color: var(--bk-muted); font-size: 0.82rem; line-height: 1.5; margin: 0; }

/* ── Landing: sanitized note ──────────────────────────────────── */
.bk-sanitized {
  font-family: var(--bk-font-mono);
  font-size: 0.74rem;
  color: var(--bk-dim);
  border-top: 1px dashed var(--bk-border2);
  margin-top: 2.4rem;
  padding-top: 0.9rem;
  line-height: 1.7;
}

/* ── Motion off ───────────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}