/* Pointer glow — shared by index.html, plans.html, and the subpages.
   Pairs with background.js, which sets --mx/--my on :root.
   The grid itself is static; the only motion is the light following the
   cursor. */

/* Soft glow trailing the pointer. */
.cursor-glow {
    position: fixed;
    top: 0;
    left: 0;
    width: 160px;
    height: 160px;
    /* Centre the circle on the pointer, so the JS only has to translate. */
    margin: -80px 0 0 -80px;
    border-radius: 50%;
    background: radial-gradient(circle,
        rgba(0, 102, 255, 0.22) 0%,
        rgba(6, 182, 212, 0.10) 40%,
        transparent 70%);
    filter: blur(20px);
    pointer-events: none;
    opacity: 0;
    z-index: 0;
    transition: opacity 0.4s ease;
    will-change: transform;
}

/* A brighter copy of the grid, revealed only near the pointer.
   The mask lives on this wrapper rather than on the grid itself: the grid
   drifts via gridMove, and a mask on a moving element would drift along with
   it instead of staying under the pointer. */
.grid-glow {
    position: fixed;
    inset: 0;
    pointer-events: none;
    opacity: 0;
    z-index: 0;
    transition: opacity 0.4s ease;
    -webkit-mask-image: radial-gradient(circle 120px at var(--mx, -999px) var(--my, -999px),
        #000 0%, rgba(0, 0, 0, 0.4) 50%, transparent 75%);
    mask-image: radial-gradient(circle 120px at var(--mx, -999px) var(--my, -999px),
        #000 0%, rgba(0, 0, 0, 0.4) 50%, transparent 75%);
}

.grid-background--lit {
    background-image:
        linear-gradient(rgba(0, 163, 255, 0.30) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 163, 255, 0.30) 1px, transparent 1px);
}

body.cursor-active .cursor-glow,
body.cursor-active .grid-glow {
    opacity: 1;
}

/* No pointer to follow on touch devices. */
@media (hover: none), (pointer: coarse) {
    .cursor-glow,
    .grid-glow {
        display: none;
    }
}

@media (prefers-reduced-motion: reduce) {
    .cursor-glow,
    .grid-glow {
        display: none;
    }
}