/* ============================================================
   Infinite Circle Field — all tunable values live here.
   Edit the custom properties below; nothing else needs to change.
   ============================================================ */

:root {
  /* Page */
  --bg: #FFFFFF;

  /* Grid circles: random fill picked between these two colors */
  --circle-dark:   #c38951;  /* medium-dark brown */
  --circle-light:  #a29134;  /* light brown */

  /* Hover overlay circle: random fill picked between these two colors */
  --overlay-start: #fff223;  /* light yellow */
  --overlay-end:   #f8f6aa;  /* near-white cream */

  /* Sizes */
  --circle-size: 14px;   /* diameter of a grid circle */
  --cell-size: 48px;     /* grid pitch; spacing = cell-size - circle-size */
  --overlay-size: 160px; /* diameter of the hover overlay circle */

  /* Motion */
  --fade-in: 320ms;      /* new circles arriving via infinite scroll */
  --overlay-in: 200ms;
  --overlay-out: 160ms;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

* { box-sizing: border-box; }

html { background: var(--bg); }

body {
  margin: 0;
  background: var(--bg);
  overflow-x: hidden;
}

/* Screen-reader-only title; the field itself is decorative. */
.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- Grid ---------- */

#field {
  /* padding-top is managed by app.js to hold scroll position steady
     as rows above the viewport are recycled out of the DOM. */
  padding-top: 0;
}

.row {
  display: grid;
  /* grid-template-columns is set from app.js once the column count is known */
  justify-content: center;
  height: var(--cell-size);
}

.dot {
  width: var(--circle-size);
  height: var(--circle-size);
  margin: auto;
  border-radius: 50%;
  opacity: 0;
  transform: scale(.6);
  transition:
    opacity var(--fade-in) var(--ease),
    transform var(--fade-in) var(--ease);
  will-change: opacity, transform;
}

.dot.is-in {
  opacity: 1;
  transform: scale(1);
}

/* ---------- Hover overlay ---------- */

#overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--overlay-size);
  height: var(--overlay-size);
  border-radius: 50%;
  pointer-events: none;
  opacity: 0;
  z-index: 10;
  transition:
    opacity var(--overlay-out) var(--ease),
    transform var(--overlay-out) var(--ease);
  will-change: opacity, transform;
}

#overlay.is-visible {
  opacity: 1;
  transition:
    opacity var(--overlay-in) var(--ease),
    transform var(--overlay-in) var(--ease);
}

/* ---------- Reduced motion ---------- */

@media (prefers-reduced-motion: reduce) {
  .dot,
  #overlay,
  #overlay.is-visible {
    transition-duration: 1ms !important;
    transition-delay: 0ms !important;
  }
}