/* Decorative orientation cues only: no runtime state, polling or live telemetry. */
.system-journey{position:relative}
.journey-signal{position:absolute;left:calc(var(--gutter)/2 - 8px);top:28px;width:16px;height:calc(100% - 273px);z-index:2;pointer-events:none;overflow:hidden}
.journey-path{fill:none;stroke:#9a8051;stroke-width:1.4;stroke-linecap:round;stroke-dasharray:3 200;stroke-dashoffset:3;opacity:0;vector-effect:non-scaling-stroke}

@media(prefers-reduced-motion:no-preference){
  .math-overlay{animation:notation-materialize 1200ms ease-out 160ms both}
  .math-two{animation-delay:320ms}
  .journey-path{animation:journey-trace 5s ease-in-out 1400ms both}
  .economic-flow i{animation:mechanism-pulse 1100ms ease-in-out 2300ms both}
  .economic-flow i:nth-of-type(2){animation-delay:2650ms}
  .economic-flow i:nth-of-type(3){animation-delay:3000ms}
  .evidence summary>span{transition:transform 180ms ease-out}
  .evidence[open]>div{animation:evidence-reveal 180ms ease-out}

  /* A single tracer follows reading progress when native scroll timelines exist.
     Older browsers receive one finite orientation sweep instead. */
  @supports(animation-timeline:view()){
    .system-journey{view-timeline-name:--system-journey;view-timeline-axis:block}
    .journey-path{animation:journey-trace linear both;animation-timeline:--system-journey;animation-range:contain 0% contain 100%}
    .economic-flow{view-timeline-name:--mechanism;view-timeline-axis:block}
    .economic-flow i{animation:mechanism-pulse linear both;animation-timeline:--mechanism;animation-range:entry 0% cover 35%}
    .economic-flow i:nth-of-type(2){animation-range:entry 12% cover 47%}
    .economic-flow i:nth-of-type(3){animation-range:entry 24% cover 59%}
  }

  /* Progressive native disclosure interpolation retains real summary controls. */
  @supports(interpolate-size:allow-keywords){
    .evidence{interpolate-size:allow-keywords}
    .evidence::details-content{block-size:0;opacity:0;overflow:clip;transition:block-size 240ms ease-out,opacity 180ms ease-out,content-visibility 240ms allow-discrete}
    .evidence[open]::details-content{block-size:auto;opacity:1}
    .evidence[open]>div{animation:none}
  }
}

@keyframes notation-materialize{from{opacity:.12}to{opacity:1}}
@keyframes journey-trace{0%{stroke-dashoffset:3;opacity:0}8%{opacity:.65}92%{opacity:.65}100%{stroke-dashoffset:-100;opacity:0}}
@keyframes mechanism-pulse{0%,100%{opacity:1}40%{opacity:.48}65%{opacity:1}}
@keyframes evidence-reveal{from{opacity:.15}to{opacity:1}}

@media(max-width:1100px){.journey-signal{left:2px;width:12px}}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .journey-signal{display:none}
  .math-overlay,.journey-path,.economic-flow i,.evidence summary>span,.evidence>div,.evidence::details-content{animation:none!important;transition:none!important}
}