/* Inline SVG diagrams.

   The diagrams are authored by hand in the post source rather than generated at
   runtime, so this file only has to do two things: give the figure a frame that
   matches the site chrome, and expose a palette the SVG shapes reference by
   class. Theme switching is pure CSS — nothing re-renders on toggle.

   Same three-state theming as the rest of the site:
     1. :root                              → light
     2. :root[data-theme="dark"]           → user chose dark (persisted)
     3. @media (prefers-color-scheme:dark) → follow the OS, unless forced light
   Every color is declared on bare :root first; the dark blocks only re-point
   the custom properties, so each rule below has one source of truth. */

:root {
  --diagram-control-size: 1.9rem;
  --diagram-control-icon-size: 0.85rem;
  --diagram-control-size-mobile: 1.75rem;
  --diagram-lightbox-close-size: 2.35rem;
  --diagram-lightbox-close-size-mobile: 2.15rem;

  /* Frame */
  --dg-frame-border: rgba(17, 24, 39, 0.12);
  --dg-frame-bg: linear-gradient(180deg, rgba(249, 250, 251, 0.96), rgba(255, 255, 255, 0.98));
  --dg-frame-shadow: 0 14px 30px rgba(15, 23, 42, 0.06);
  --dg-frame-border-hover: rgba(17, 24, 39, 0.24);
  --dg-frame-shadow-hover: 0 16px 34px rgba(15, 23, 42, 0.09);

  --dg-ctrl-border: rgba(17, 24, 39, 0.08);
  --dg-ctrl-bg: rgba(255, 255, 255, 0.82);
  --dg-ctrl-bg-hover: rgba(255, 255, 255, 0.96);
  --dg-ctrl-shadow: 0 10px 24px rgba(15, 23, 42, 0.1);
  --dg-expand-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23111827' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M15 3h6v6'/%3E%3Cpath d='M9 21H3v-6'/%3E%3Cpath d='M21 3l-7 7'/%3E%3Cpath d='M3 21l7-7'/%3E%3C/svg%3E");

  --dg-panel-bg: linear-gradient(180deg, rgba(249, 250, 251, 0.98), rgba(255, 255, 255, 1));
  --dg-panel-shadow: 0 24px 80px rgba(15, 23, 42, 0.28);

  --dg-close-bg: rgba(255, 255, 255, 0.9);
  --dg-close-bg-hover: rgba(255, 255, 255, 1);
  --dg-close-shadow: 0 10px 28px rgba(15, 23, 42, 0.12);
  --dg-close-shadow-hover: 0 14px 34px rgba(15, 23, 42, 0.16);
  --dg-close-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23111827' stroke-width='2.1' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M18 6 6 18'/%3E%3Cpath d='m6 6 12 12'/%3E%3C/svg%3E");

  /* Edges */
  --dg-line: #94a3b8;
  --dg-edge-label: #5b5e66;

  /* Node roles. Colour carries meaning here (decision / good / bad), the one
     place the otherwise-monochrome site spends hue, same exception the syntax
     theme takes. */
  --dg-hub-bg: #1f2937;
  --dg-hub-border: #111827;
  --dg-hub-ink: #ffffff;

  --dg-neutral-bg: #f5f7fa;
  --dg-neutral-border: #94a3b8;
  --dg-neutral-ink: #1f2937;

  --dg-blue-bg: #e8f2ff;
  --dg-blue-border: #3b82f6;
  --dg-blue-ink: #1e3a8a;

  --dg-purple-bg: #f1e9ff;
  --dg-purple-border: #8b5cf6;
  --dg-purple-ink: #4c1d95;

  --dg-teal-bg: #e3f7ef;
  --dg-teal-border: #10b981;
  --dg-teal-ink: #065f46;

  --dg-decision-bg: #fff4e0;
  --dg-decision-border: #f59e0b;
  --dg-decision-ink: #92400e;

  --dg-good-bg: #e6f7f1;
  --dg-good-border: #10b981;
  --dg-good-ink: #065f46;

  --dg-bad-bg: #fdeaea;
  --dg-bad-border: #ef4444;
  --dg-bad-ink: #991b1b;
}

/* ---------------------------------------------------------------------------
   Frame
   --------------------------------------------------------------------------- */

.post-content .diagram {
  position: relative;
  margin: 1.5rem 0;
  padding: 1rem;
  border: 1px solid var(--dg-frame-border);
  border-radius: 16px;
  background: var(--dg-frame-bg);
  box-shadow: var(--dg-frame-shadow);
  overflow: hidden;
  cursor: zoom-in;
  transition:
    box-shadow 160ms ease,
    border-color 160ms ease;
}

.post-content .diagram__viewport {
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-gutter: stable both-edges;
}

/* Scale to the column, but stop shrinking before the labels stop being
   readable — below that the viewport scrolls and the lightbox takes over. */
.post-content .diagram svg {
  display: block;
  width: 100%;
  min-width: 600px;
  height: auto;
  margin: 0 auto;
}

.post-content .diagram::after {
  content: "";
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  width: var(--diagram-control-size);
  height: var(--diagram-control-size);
  border: 1px solid var(--dg-ctrl-border);
  border-radius: 999px;
  background-color: var(--dg-ctrl-bg);
  background-image: var(--dg-expand-icon);
  background-repeat: no-repeat;
  background-position: center;
  background-size: var(--diagram-control-icon-size) var(--diagram-control-icon-size);
  box-shadow: var(--dg-ctrl-shadow);
  opacity: 0.72;
  pointer-events: none;
  transition:
    opacity 160ms ease,
    transform 160ms ease,
    background-color 160ms ease;
}

.post-content .diagram:hover,
.post-content .diagram:focus-visible {
  border-color: var(--dg-frame-border-hover);
  box-shadow: var(--dg-frame-shadow-hover);
}

.post-content .diagram:hover::after,
.post-content .diagram:focus-visible::after {
  opacity: 1;
  transform: scale(1.04);
  background-color: var(--dg-ctrl-bg-hover);
}

.post-content .diagram:focus-visible {
  outline: 3px solid var(--dg-neutral-border);
  outline-offset: 3px;
}

/* ---------------------------------------------------------------------------
   SVG internals — shapes carry a role class, this maps roles to the palette.
   --------------------------------------------------------------------------- */

.dg text {
  font-family: inherit;
  font-weight: 500;
}

.dg .dg-node { stroke-width: 1.5; rx: 8; }

.dg .dg-hub      { fill: var(--dg-hub-bg);      stroke: var(--dg-hub-border); }
.dg .dg-neutral  { fill: var(--dg-neutral-bg);  stroke: var(--dg-neutral-border); }
.dg .dg-blue     { fill: var(--dg-blue-bg);     stroke: var(--dg-blue-border); }
.dg .dg-purple   { fill: var(--dg-purple-bg);   stroke: var(--dg-purple-border); }
.dg .dg-teal     { fill: var(--dg-teal-bg);     stroke: var(--dg-teal-border); }
.dg .dg-decision { fill: var(--dg-decision-bg); stroke: var(--dg-decision-border); }
.dg .dg-good     { fill: var(--dg-good-bg);     stroke: var(--dg-good-border); }
.dg .dg-bad      { fill: var(--dg-bad-bg);      stroke: var(--dg-bad-border); }

.dg .dg-t-hub      { fill: var(--dg-hub-ink); }
.dg .dg-t-neutral  { fill: var(--dg-neutral-ink); }
.dg .dg-t-blue     { fill: var(--dg-blue-ink); }
.dg .dg-t-purple   { fill: var(--dg-purple-ink); }
.dg .dg-t-teal     { fill: var(--dg-teal-ink); }
.dg .dg-t-decision { fill: var(--dg-decision-ink); }
.dg .dg-t-good     { fill: var(--dg-good-ink); }
.dg .dg-t-bad      { fill: var(--dg-bad-ink); }

.dg .dg-edge {
  fill: none;
  stroke: var(--dg-line);
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.dg .dg-arrowhead { fill: var(--dg-line); }

.dg .dg-edge-label {
  fill: var(--dg-edge-label);
  font-size: 11.5px;
  font-weight: 600;
}

/* ---------------------------------------------------------------------------
   Lightbox
   --------------------------------------------------------------------------- */

body.diagram-lightbox-open { overflow: hidden; }

.diagram-lightbox {
  position: fixed;
  inset: 0;
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  background: rgba(15, 23, 42, 0.72);
  backdrop-filter: blur(8px);
}

.diagram-lightbox__panel {
  width: min(1200px, 100%);
  max-height: min(90vh, 980px);
  position: relative;
  overflow: hidden;
  padding: 1rem;
  border-radius: 22px;
  background: var(--dg-panel-bg);
  box-shadow: var(--dg-panel-shadow);
}

.diagram-lightbox__close {
  position: absolute;
  top: 0.9rem;
  right: 0.9rem;
  z-index: 1;
  width: var(--diagram-lightbox-close-size);
  height: var(--diagram-lightbox-close-size);
  border: 1px solid var(--dg-ctrl-border);
  border-radius: 999px;
  background: var(--dg-close-bg);
  box-shadow: var(--dg-close-shadow);
  cursor: pointer;
  transition:
    transform 160ms ease,
    background-color 160ms ease,
    box-shadow 160ms ease;
}

.diagram-lightbox__close::before {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  width: var(--diagram-control-icon-size);
  height: var(--diagram-control-icon-size);
  background-image: var(--dg-close-icon);
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
}

.diagram-lightbox__close:hover,
.diagram-lightbox__close:focus-visible {
  background: var(--dg-close-bg-hover);
  box-shadow: var(--dg-close-shadow-hover);
  transform: scale(1.04);
}

.diagram-lightbox__content {
  overflow: auto;
  max-height: calc(90vh - 2rem);
  border-radius: 16px;
}

.diagram-lightbox__stage {
  width: fit-content;
  min-width: 100%;
  margin: 0 auto;
}

.diagram-lightbox__content svg {
  display: block;
  width: auto;
  max-width: none;
  height: auto;
  margin: 0 auto;
}

/* ---------------------------------------------------------------------------
   Dark mode — re-point the custom properties only.
   --------------------------------------------------------------------------- */

:root[data-theme="dark"] {
  --dg-frame-border: rgba(255, 255, 255, 0.12);
  --dg-frame-bg: linear-gradient(180deg, #16171b, #111214);
  --dg-frame-shadow: 0 14px 30px rgba(0, 0, 0, 0.5);
  --dg-frame-border-hover: rgba(255, 255, 255, 0.28);
  --dg-frame-shadow-hover: 0 16px 34px rgba(0, 0, 0, 0.6);

  --dg-ctrl-border: rgba(255, 255, 255, 0.12);
  --dg-ctrl-bg: rgba(22, 22, 25, 0.85);
  --dg-ctrl-bg-hover: rgba(30, 30, 34, 0.96);
  --dg-ctrl-shadow: 0 10px 24px rgba(0, 0, 0, 0.5);
  --dg-expand-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ededed' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M15 3h6v6'/%3E%3Cpath d='M9 21H3v-6'/%3E%3Cpath d='M21 3l-7 7'/%3E%3Cpath d='M3 21l7-7'/%3E%3C/svg%3E");

  --dg-panel-bg: linear-gradient(180deg, #16171b, #111214);
  --dg-panel-shadow: 0 24px 80px rgba(0, 0, 0, 0.7);

  --dg-close-bg: rgba(22, 22, 25, 0.9);
  --dg-close-bg-hover: rgba(34, 34, 38, 1);
  --dg-close-shadow: 0 10px 28px rgba(0, 0, 0, 0.5);
  --dg-close-shadow-hover: 0 14px 34px rgba(0, 0, 0, 0.6);
  --dg-close-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ededed' stroke-width='2.1' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M18 6 6 18'/%3E%3Cpath d='m6 6 12 12'/%3E%3C/svg%3E");

  --dg-line: #8b8d94;
  --dg-edge-label: #b0b1b7;

  --dg-hub-bg: #ededed;
  --dg-hub-border: #ffffff;
  --dg-hub-ink: #0d0d0f;

  --dg-neutral-bg: #23242b;
  --dg-neutral-border: #6b7280;
  --dg-neutral-ink: #e5e7eb;

  --dg-blue-bg: #14243d;
  --dg-blue-border: #60a5fa;
  --dg-blue-ink: #bfdbfe;

  --dg-purple-bg: #241a3d;
  --dg-purple-border: #a78bfa;
  --dg-purple-ink: #ddd6fe;

  --dg-teal-bg: #102b23;
  --dg-teal-border: #34d399;
  --dg-teal-ink: #a7f3d0;

  --dg-decision-bg: #33240d;
  --dg-decision-border: #fbbf24;
  --dg-decision-ink: #fde68a;

  --dg-good-bg: #102b23;
  --dg-good-border: #34d399;
  --dg-good-ink: #a7f3d0;

  --dg-bad-bg: #3a1618;
  --dg-bad-border: #f87171;
  --dg-bad-ink: #fecaca;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --dg-frame-border: rgba(255, 255, 255, 0.12);
    --dg-frame-bg: linear-gradient(180deg, #16171b, #111214);
    --dg-frame-shadow: 0 14px 30px rgba(0, 0, 0, 0.5);
    --dg-frame-border-hover: rgba(255, 255, 255, 0.28);
    --dg-frame-shadow-hover: 0 16px 34px rgba(0, 0, 0, 0.6);

    --dg-ctrl-border: rgba(255, 255, 255, 0.12);
    --dg-ctrl-bg: rgba(22, 22, 25, 0.85);
    --dg-ctrl-bg-hover: rgba(30, 30, 34, 0.96);
    --dg-ctrl-shadow: 0 10px 24px rgba(0, 0, 0, 0.5);
    --dg-expand-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ededed' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M15 3h6v6'/%3E%3Cpath d='M9 21H3v-6'/%3E%3Cpath d='M21 3l-7 7'/%3E%3Cpath d='M3 21l7-7'/%3E%3C/svg%3E");

    --dg-panel-bg: linear-gradient(180deg, #16171b, #111214);
    --dg-panel-shadow: 0 24px 80px rgba(0, 0, 0, 0.7);

    --dg-close-bg: rgba(22, 22, 25, 0.9);
    --dg-close-bg-hover: rgba(34, 34, 38, 1);
    --dg-close-shadow: 0 10px 28px rgba(0, 0, 0, 0.5);
    --dg-close-shadow-hover: 0 14px 34px rgba(0, 0, 0, 0.6);
    --dg-close-icon: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ededed' stroke-width='2.1' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M18 6 6 18'/%3E%3Cpath d='m6 6 12 12'/%3E%3C/svg%3E");

    --dg-line: #8b8d94;
    --dg-edge-label: #b0b1b7;

    --dg-hub-bg: #ededed;
    --dg-hub-border: #ffffff;
    --dg-hub-ink: #0d0d0f;

    --dg-neutral-bg: #23242b;
    --dg-neutral-border: #6b7280;
    --dg-neutral-ink: #e5e7eb;

    --dg-blue-bg: #14243d;
    --dg-blue-border: #60a5fa;
    --dg-blue-ink: #bfdbfe;

    --dg-purple-bg: #241a3d;
    --dg-purple-border: #a78bfa;
    --dg-purple-ink: #ddd6fe;

    --dg-teal-bg: #102b23;
    --dg-teal-border: #34d399;
    --dg-teal-ink: #a7f3d0;

    --dg-decision-bg: #33240d;
    --dg-decision-border: #fbbf24;
    --dg-decision-ink: #fde68a;

    --dg-good-bg: #102b23;
    --dg-good-border: #34d399;
    --dg-good-ink: #a7f3d0;

    --dg-bad-bg: #3a1618;
    --dg-bad-border: #f87171;
    --dg-bad-ink: #fecaca;
  }
}

@media (max-width: 700px) {
  :root {
    --diagram-control-size: var(--diagram-control-size-mobile);
    --diagram-lightbox-close-size: var(--diagram-lightbox-close-size-mobile);
  }

  .post-content .diagram {
    margin: 1.25rem -0.25rem;
    padding: 0.85rem;
    border-radius: 14px;
  }

  .post-content .diagram::after {
    top: 0.6rem;
    right: 0.6rem;
  }

  .diagram-lightbox { padding: 1rem; }

  .diagram-lightbox__panel {
    max-height: 92vh;
    padding: 0.85rem;
    border-radius: 18px;
  }

  .diagram-lightbox__close {
    top: 0.7rem;
    right: 0.7rem;
  }

  .diagram-lightbox__content { max-height: calc(92vh - 1.7rem); }

  .diagram-lightbox__stage { min-width: max-content; }
}

@media (prefers-reduced-motion: reduce) {
  .post-content .diagram,
  .post-content .diagram::after,
  .diagram-lightbox__close {
    transition: none;
  }
}