/* Pagina Depliant: pieghevole 3D a 3 ante */
.dp-rings { left: 50%; top: 52vh; }
.dp { max-width: 1320px; margin: 0 auto; padding: clamp(20px, 4vh, 48px) var(--pad) clamp(56px, 10vh, 110px); }
.dp-intro { text-align: center; display: grid; justify-items: center; }
.dp-lead { max-width: 44ch; }

/* --- palco 3D --- */
.dp-viewer { margin-top: clamp(20px, 4vh, 40px); display: grid; justify-items: center; }
.dp-stage {
  --pw: 400px; --ph: 567.5px;           /* misura base di un'anta (A4 verticale) */
  --s: 1; --tx: 0px; --rl: 180deg; --rr: -180deg; --ry: 0deg; --zl: 3px; --zr: 1px;
  position: relative; width: 100%; height: calc(var(--ph) * var(--s) + 40px);
  perspective: 3200px; outline: none; cursor: pointer; touch-action: pan-y;
  transition: height .9s cubic-bezier(.65,0,.35,1);
}
.dp-stage:focus-visible { outline: 3px solid var(--ink); outline-offset: 6px; border-radius: 20px; }
.dp-sheet {
  position: absolute; left: 50%; top: 50%; width: var(--pw); height: var(--ph);
  margin: calc(var(--ph) / -2) 0 0 calc(var(--pw) / -2);
  transform-style: preserve-3d;
  transform: translateX(var(--tx)) scale(var(--s)) rotateY(var(--ry));
  transition: transform .9s cubic-bezier(.65,0,.35,1);
}
.dp-panel { position: absolute; top: 0; width: var(--pw); height: var(--ph); transform-style: preserve-3d;
  transition: transform .9s cubic-bezier(.65,0,.35,1); }
.dp-mid { left: 0; }
.dp-left { left: calc(var(--pw) * -1); transform-origin: right center; transform: translateZ(var(--zl)) rotateY(var(--rl)); }
.dp-right { left: var(--pw); transform-origin: left center; transform: translateZ(var(--zr)) rotateY(var(--rr)); }
.dp-face { position: absolute; inset: 0; backface-visibility: hidden; -webkit-backface-visibility: hidden;
  background: #fff center / cover no-repeat; box-shadow: 0 30px 60px -30px rgba(0,0,0,.45); }
.dp-back { transform: rotateY(180deg); }
/* ombra della piega */
.dp-face::after { content: ""; position: absolute; inset: 0; pointer-events: none; opacity: .5; transition: opacity .9s; }
.dp-left .dp-front::after, .dp-mid .dp-back::after { background: linear-gradient(to left, rgba(0,0,0,.14), transparent 9%); }
.dp-right .dp-front::after, .dp-mid .dp-front::after { background: linear-gradient(to right, rgba(0,0,0,.12), transparent 9%); }
.dp-right .dp-back::after, .dp-left .dp-back::after { background: none; }

/* passi: 0 chiuso · 1 copertina aperta · 2 interno · 3 esterno */
.dp-stage[data-step="1"] { --rl: 0deg; --zl: 0px; --tx: calc(var(--pw) * var(--s) / 2); }
.dp-stage[data-step="2"] { --rl: 0deg; --rr: 0deg; --zl: 0px; --zr: 0px; }
.dp-stage[data-step="3"] { --rl: 0deg; --rr: 0deg; --zl: 0px; --zr: 0px; --ry: 180deg; }
.dp-stage[data-step="0"] .dp-sheet { animation: dp-invito 3.2s 1.2s ease-in-out infinite; }
@keyframes dp-invito { 0%, 70%, 100% { rotate: 0deg; } 80% { rotate: -2deg; } 90% { rotate: 1.5deg; } }
.dp-stage[data-step="0"]:hover .dp-left { --rl: 166deg; }

/* --- comandi --- */
.dp-controls { display: flex; align-items: center; justify-content: center; gap: 10px; margin-top: 18px; width: 100%; }
.dp-arrow {
  flex: none; width: 48px; height: 48px; border: 0; border-radius: 50%; cursor: pointer; display: grid; place-items: center;
  background: var(--pill-bg); color: var(--pill-ink); box-shadow: 0 12px 24px -14px rgba(0,0,0,.45);
  transition: transform .2s cubic-bezier(.3,1.4,.5,1), opacity .2s;
}
.dp-arrow svg { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 2.4; stroke-linecap: round; stroke-linejoin: round; }
.dp-arrow:hover { transform: scale(1.07); }
.dp-arrow:disabled { opacity: .35; cursor: default; transform: none; }
.dp-arrow:focus-visible { outline: 3px solid var(--ink); outline-offset: 3px; }
.dp-steps { display: flex; gap: 4px; margin: 0; padding: 5px; list-style: none; border-radius: 999px; background: var(--pill-bg);
  box-shadow: 0 12px 24px -14px rgba(0,0,0,.45); overflow-x: auto; min-width: 0; scrollbar-width: none; }
.dp-steps::-webkit-scrollbar { display: none; }
.dp-steps button { border: 0; background: none; cursor: pointer; white-space: nowrap; padding: 10px 16px; border-radius: 999px;
  font: 700 14px/1 var(--font-body, inherit); color: var(--pill-ink); transition: background .3s, color .3s; }
.dp-steps button[aria-current="step"] { background: var(--accent); color: var(--accent-ink); }
.dp-steps button:focus-visible { outline: 3px solid var(--ink); outline-offset: -3px; }
.dp-hint { margin: 14px 0 0; min-height: 1.4em; font-size: 14px; font-weight: 700; color: var(--ink-soft); text-align: center; }

/* --- tutte le ante --- */
.dp-ante { margin-top: clamp(48px, 8vh, 90px); text-align: center; display: grid; justify-items: center; }
.dp-ante .cs-h3 { margin: 0; }
.dp-ante-sub { margin: 8px 0 0; color: var(--ink-soft); }
.dp-thumbs { list-style: none; margin: 26px 0 0; padding: 0; width: 100%;
  display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: clamp(10px, 1.6vw, 22px); }
.dp-thumbs button { all: unset; display: grid; gap: 10px; cursor: pointer; width: 100%; text-align: center; }
.dp-thumbs img { width: 100%; aspect-ratio: 593.6 / 842.3; object-fit: cover; display: block; border-radius: 6px; background: #fff;
  box-shadow: 0 18px 30px -20px rgba(0,0,0,.5); transition: transform .3s cubic-bezier(.3,1.4,.5,1); }
.dp-thumbs span { font-size: 13px; font-weight: 700; line-height: 1.25; }
.dp-thumbs button:hover img { transform: translateY(-4px) rotate(-1deg); }
.dp-thumbs button:focus-visible img { outline: 3px solid var(--ink); outline-offset: 4px; }
.dp-pdf { margin-top: 36px; text-decoration: none; }

/* --- lente --- */
.dp-zoom { width: 100vw; height: 100dvh; max-width: none; max-height: none; margin: 0; padding: 0; border: 0;
  background: rgba(24, 12, 8, .94); color: #fff; display: none; flex-direction: column; }
.dp-zoom[open] { display: flex; }
.dp-zoom::backdrop { background: transparent; }
.dp-zoom-bar { display: flex; align-items: center; gap: 10px; padding: 14px var(--pad); }
.dp-zoom-t { margin: 0 auto 0 0; font-size: 15px; }
.dp-zoom-t span { opacity: .7; margin-right: 6px; }
.dp-zoom .dp-arrow { background: rgba(255,255,255,.12); color: #fff; box-shadow: none; }
.dp-zoom .dp-close { margin-left: 8px; }
.dp-zoom-box { flex: 1; overflow: auto; display: grid; place-items: center; padding: 0 var(--pad); overscroll-behavior: contain; }
.dp-zoom-box img { display: block; max-height: calc(100dvh - 120px); max-width: 100%; height: auto; width: auto;
  cursor: zoom-in; background: #fff; box-shadow: 0 30px 80px rgba(0,0,0,.5); }
.dp-zoom-box.zoomed { place-items: start; }
.dp-zoom-box.zoomed img { max-height: none; max-width: none; width: 1800px; cursor: zoom-out; margin: 0 auto; }
.dp-zoom-hint { margin: 0; padding: 10px; text-align: center; font-size: 13px; opacity: .7; }

@media (max-width: 760px) {
  .dp-thumbs { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .dp-steps button { padding: 9px 12px; font-size: 13px; }
  .dp-arrow { width: 42px; height: 42px; }
  .dp-pdf { width: 100%; justify-content: space-between; }
  .dp-zoom-box.zoomed img { width: 1400px; }
}
@media (max-width: 420px) {
  .dp-controls { gap: 6px; }
  .dp-steps { gap: 0; padding: 4px; }
  .dp-steps button { padding: 9px 9px; font-size: 12.5px; }
  .dp-arrow { width: 38px; height: 38px; }
}
@media (prefers-reduced-motion: reduce) {
  .dp-stage, .dp-sheet, .dp-panel, .dp-face::after { transition-duration: .01s; }
  .dp-stage[data-step="0"] .dp-sheet { animation: none; }
}