/* intro v28 — Arc diagonal-split: clip split, floating rings, ransom-note words, grayscale hover, click burst */

/* Diagonal split zone */
.intro-arc2__split {
    clip-path: polygon(0 0, 100% 0, 100% 62%, 0 100%);
    opacity: 0.6;
}

/* Floating rings / donuts (fixed size — no BS w-N/h-N utility) */
.intro-arc2__ring { width: 10rem; height: 10rem; animation: intro-arc2-float 7s ease-in-out infinite; }
.intro-arc2__ring--2 { width: 6rem; height: 6rem; animation-duration: 9s; animation-delay: 1s; }
@keyframes intro-arc2-float {
    50% { transform: translateY(-1.2rem) rotate(20deg); }
}

/* Serif accent (paired with sans body) */
.intro-arc2__serif { font-family: ui-serif, Georgia, "Times New Roman", serif; }

/* Hero image grayscale → colour reveal on hover */
.intro-arc2__figure { aspect-ratio: 4 / 3; }
.intro-arc2__img {
    object-fit: cover;
    filter: grayscale(1);
    transition: filter 420ms ease;
}
.intro-arc2__figure:hover .intro-arc2__img { filter: grayscale(0); }

/* Ransom-note mixed letters: alternate rotation, weight, family (no colour) */
.intro-arc2__word {
    display: inline-block;
    margin-right: 0.25em;
}
.intro-arc2__word:nth-child(3n+1) { transform: rotate(-4deg); font-weight: 900; }
.intro-arc2__word:nth-child(3n+2) { transform: rotate(3deg);  font-family: ui-serif, Georgia, serif; font-style: italic; }
.intro-arc2__word:nth-child(3n+3) { transform: rotate(-1deg); font-weight: 700; text-transform: uppercase; }

/* Click burst spark (inherits the button's primary colour via currentColor) */
.intro-arc2__react { position: relative; overflow: visible; }
.intro-arc2__spark {
    position: absolute;
    left: 50%;
    top: 50%;
    pointer-events: none;
    animation: intro-arc2-burst 640ms ease-out forwards;
}
@keyframes intro-arc2-burst {
    to { opacity: 0; transform: translate(var(--dx), var(--dy)) scale(0.4) rotate(160deg); }
}

@media (prefers-reduced-motion: reduce) {
    .intro-arc2__ring { animation: none; }
}

/* FAQ v18 — accordion mechanics */
.faq-accordion-panel {
    max-height: 0;
}

.faq-accordion-icon.solver-hints-symbol-reveal {
    transform: rotate(180deg);
}