/* Infinito 3D a scorrimento: palco "sticky" lungo 5 schermi; lo scroll è la manovella.
   Fondo: tunnel fotografico che si ingrandisce e ruota piano con lo scroll (solo CSS). */

body {
	background: #04070a;
}

.corsa {
	height: 520svh;
	position: relative;
}
.palco {
	position: sticky;
	top: 0;
	height: 100svh;
	overflow: hidden;
	isolation: isolate;
}

.fondo,
.velo,
#scena {
	position: absolute;
	inset: 0;
}
.fondo {
	z-index: 0;
	overflow: hidden;
}
.fondo img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	display: block;
	transform-origin: 50% 50%;
}
.velo {
	z-index: 1;
	pointer-events: none;
	background:
		radial-gradient(ellipse at center, transparent 30%, rgb(2 4 8 / 0.55)),
		linear-gradient(180deg, rgb(2 4 8 / 0.55), transparent 28%, transparent 55%, rgb(2 4 8 / 0.8));
}
#scena {
	z-index: 2;
	pointer-events: none;
}

/* Il tunnel "viaggia" con lo scroll. Dove la scroll timeline non c'è resta fermo; con
   «riduci movimento» pure. */
@supports (animation-timeline: scroll()) {
	@media (prefers-reduced-motion: no-preference) {
		.fondo img {
			animation: viaggio linear both;
			animation-timeline: scroll(root block);
		}
		.avanzamento span {
			animation: riempi linear both;
			animation-timeline: scroll(root block);
		}
	}
}
@keyframes viaggio {
	from {
		transform: scale(1) rotate(0deg);
	}
	to {
		transform: scale(2.1) rotate(24deg);
	}
}
@keyframes riempi {
	from {
		transform: scaleY(0);
	}
	to {
		transform: scaleY(1);
	}
}

/* La firma sta in alto a sinistra sopra il palco; il piede "Realizzato da" è sotto la corsa. */
body > nav[aria-label='Loop Studio'] {
	position: fixed;
	z-index: 5;
	top: 0;
	left: 0;
}
.studio-mark {
	position: relative;
	z-index: 5;
	background: #04070a;
	margin: 0;
}

.testa {
	position: absolute;
	z-index: 3;
	top: clamp(1rem, 5svh, 2.5rem);
	left: 0;
	right: 0;
	text-align: center;
	padding-inline: 1.25rem;
	pointer-events: none;
}
.kicker {
	margin-bottom: 0.4rem;
	font-size: 0.75rem;
	font-weight: 600;
	letter-spacing: 0.1em;
	text-transform: uppercase;
	color: #ffb4ae;
	text-shadow: 0 1px 12px rgb(0 0 0 / 0.8);
}
h1 {
	font-size: clamp(1.5rem, 3.6vw, 2.5rem);
	font-weight: 800;
	letter-spacing: -0.015em;
	text-shadow: 0 2px 24px rgb(0 0 0 / 0.7);
}

.didascalie {
	position: absolute;
	z-index: 3;
	left: clamp(1.25rem, 6vw, 5rem);
	bottom: clamp(1.5rem, 9svh, 5rem);
	width: min(26rem, calc(100% - 2.5rem));
	pointer-events: none;
}
.didascalia {
	position: absolute;
	left: 0;
	bottom: 0;
	width: 100%;
	opacity: 0;
	translate: 0 0.75rem;
	transition: opacity 0.35s var(--ease-out), translate 0.35s var(--ease-out);
}
.didascalia.is-on {
	opacity: 1;
	translate: 0 0;
}
.passo {
	margin-bottom: 0.5rem;
	font-size: 0.75rem;
	font-weight: 600;
	letter-spacing: 0.1em;
	color: #ff8f87;
}
h2 {
	margin-bottom: 0.6rem;
	font-size: clamp(1.6rem, 3.4vw, 2.4rem);
	font-weight: 800;
	line-height: 1.05;
	letter-spacing: -0.015em;
	text-shadow: 0 2px 24px rgb(0 0 0 / 0.8);
}
.didascalia p:last-child {
	color: rgb(255 255 255 / 0.9);
	line-height: 1.6;
	text-shadow: 0 1px 14px rgb(0 0 0 / 0.85);
}

.avanzamento {
	position: absolute;
	z-index: 3;
	right: clamp(1rem, 3vw, 2rem);
	top: 25%;
	bottom: 25%;
	width: 2px;
	background: rgb(255 255 255 / 0.18);
	border-radius: 1px;
}
.avanzamento span {
	position: absolute;
	inset: 0;
	background: var(--accent);
	transform-origin: top;
	transform: scaleY(0);
}
.suggerimento {
	position: absolute;
	z-index: 3;
	left: 50%;
	bottom: clamp(0.75rem, 3svh, 1.5rem);
	translate: -50% 0;
	font-size: 0.6875rem;
	font-weight: 600;
	letter-spacing: 0.14em;
	text-transform: uppercase;
	color: rgb(255 255 255 / 0.75);
	animation: suggerisci 2.4s var(--ease-in-out) infinite;
}
.suggerimento.is-off {
	animation: none;
	opacity: 0;
	transition: opacity 0.3s var(--ease-out);
}
@keyframes suggerisci {
	0%,
	100% {
		opacity: 0.4;
		translate: -50% 0;
	}
	50% {
		opacity: 1;
		translate: -50% 0.35rem;
	}
}
.credito {
	position: absolute;
	z-index: 3;
	right: 1rem;
	bottom: 0.6rem;
	font-size: 0.6875rem;
	color: rgb(255 255 255 / 0.6);
	text-shadow: 0 1px 6px rgb(0 0 0 / 0.8);
}

@media (max-width: 700px) {
	.testa {
		top: 4.6rem;
	}
	.didascalie {
		left: 1.25rem;
		right: 1.25rem;
		width: auto;
		bottom: 11svh;
	}
	.credito,
	.avanzamento {
		display: none;
	}
}
@media (prefers-reduced-motion: reduce) {
	.suggerimento {
		animation: none;
	}
}