*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; overflow: hidden; }
#slidesWrap { height: 100dvh; overflow-y: scroll; scroll-snap-type: y mandatory; -webkit-overflow-scrolling: touch; overscroll-behavior: contain; }
body.open-menu #slidesWrap, body.sub-side-menu-open #slidesWrap { overflow: hidden; }
.slide { height: 100dvh; scroll-snap-align: start; display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 64px 32px 48px; position: relative; overflow: hidden; gap: 20px; }
.slide--dark  { background: #111; color: #fff; }
.slide--light { background: #fff; color: #333; }

#slide-1 { background: linear-gradient(135deg, #06101e 0%, #0d1d36 42%, #061020 70%, #030a14 100%); }

.cover-face { position: absolute; left: -14%; bottom: -4%; height: 84%; width: auto; pointer-events: none; user-select: none; opacity: 0.9; mix-blend-mode: luminosity; filter: brightness(1.05) saturate(0.8); }
@media (max-width: 600px) { .cover-face { height: 58%; left: -18%; bottom: -8%; opacity: 0.68; } }

body.slide-dark .side-menu-hamburger { color: #fff; }
body.slide-dark .lang-toggle a:not(.buy-btn) { color: rgba(255,255,255,0.65); }
body.slide-dark .lang-toggle a.active:not(.buy-btn) { color: #fff; }
body.slide-dark .prev-next-nav .pn-btn { color: #fff; }

.slide-chapter { font-size: clamp(0.65rem, 1.3vw, 0.85rem); font-weight: 800; letter-spacing: 0.2em; text-transform: uppercase; opacity: 0.5; }
.slide-title { font-size: clamp(2rem, 6.5vw, 5rem); font-weight: 900; letter-spacing: -0.03em; line-height: 0.95; text-transform: uppercase; color: #e67e22; }
.slide-subtitle { font-size: clamp(1.05rem, 2.2vw, 1.4rem); font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; opacity: 0.9; }
.slide-heading { font-size: clamp(1.55rem, 3.3vw, 2.3rem); font-weight: 700; line-height: 1.3; text-align: center; max-width: 860px; }
.slide-heading strong { color: #e67e22; font-weight: 900; }
.slide-subheading { font-size: clamp(0.9rem, 1.8vw, 1.15rem); font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: #e67e22; opacity: 0.85; text-align: center; }
.slide-body { font-size: clamp(1.05rem, 1.9vw, 1.3rem); font-weight: 500; line-height: 1.62; max-width: 760px; text-align: center; opacity: 0.92; }
.slide-body strong { font-weight: 800; }
.slide-list { font-size: clamp(1rem, 1.75vw, 1.2rem); font-weight: 500; line-height: 1.7; max-width: 780px; text-align: left; opacity: 0.92; list-style: none; padding: 0; }
.slide-list li { padding-left: 1.2em; position: relative; }
.slide-list li::before { content: '›'; position: absolute; left: 0; color: #e67e22; font-weight: 900; }
.slide-list strong { color: #e67e22; font-weight: 800; }
.slide-img-wrap { width: 100%; max-width: 950px; display: flex; align-items: center; justify-content: center; flex: 1; min-height: 0; }
.slide-img { max-width: 100%; max-height: 100%; width: auto; height: auto; object-fit: contain; display: block; }
.slide-caption { font-size: 0.75rem; font-weight: 600; letter-spacing: 0.12em; text-transform: uppercase; opacity: 0.4; text-align: center; }
.slide-note { font-size: clamp(0.8rem, 1.35vw, 0.95rem); font-weight: 400; line-height: 1.7; max-width: 780px; text-align: center; opacity: 0.55; }
.slide-compare { display: flex; gap: 40px; width: 100%; max-width: 860px; }
.slide-compare-col { flex: 1; min-width: 0; }
.slide-compare-head { font-size: clamp(0.98rem, 1.3vw, 0.93rem); font-weight: 800; letter-spacing: 0.04em; color: #e67e22; margin-bottom: 6px; }
.slide-compare-body { font-size: clamp(1.15rem, 1.25vw, 0.88rem); font-weight: 500; line-height: 1.32; opacity: 0.85; }
@media (max-width: 600px) { .slide-compare { flex-direction: column; gap: 20px; } }
.slide--cols { flex-direction: row; align-items: center; gap: 48px; }
.slide--cols .slide-text-col { flex: 0 0 auto; max-width: 400px; display: flex; flex-direction: column; gap: 20px; text-align: left; }
.slide--cols .slide-text-col .slide-heading { text-align: left; }
.slide--cols .slide-text-col .slide-body { text-align: left; }
.slide--cols .slide-img-col { flex: 1; min-width: 0; min-height: 0; display: flex; align-items: center; justify-content: center; }
.slide--cols .slide-img-col img { max-width: 100%; max-height: 70dvh; width: auto; height: auto; object-fit: contain; display: block; }
#slide-3.slide--cols, #slide-16.slide--cols, #slide-20.slide--cols { justify-content: center; }
#slide-3.slide--cols .slide-text-col, #slide-16.slide--cols .slide-text-col, #slide-20.slide--cols .slide-text-col { flex: 0 1 380px; }
#slide-3.slide--cols .slide-img-col, #slide-16.slide--cols .slide-img-col, #slide-20.slide--cols .slide-img-col { flex: 0 1 520px; }
#slide-3.slide--cols .slide-img-col img { max-height: 84dvh; }
@media (max-width: 700px) { .slide--cols { flex-direction: column; } .slide--cols .slide-text-col { max-width: 100%; text-align: center; } .slide--cols .slide-text-col .slide-heading, .slide--cols .slide-text-col .slide-body { text-align: center; } }
.slide-cover-inner { display: flex; flex-direction: column; align-items: flex-start; gap: 12px; max-width: 900px; width: 100%; position: relative; z-index: 1; }
.slide-cover-divider { width: 60px; height: 3px; background: #e67e22; }
.cta-inner { display: flex; flex-direction: column; align-items: center; gap: 28px; max-width: 700px; width: 100%; position: relative; z-index: 1; }
.cta-headline { font-size: clamp(2rem, 5vw, 3.2rem); font-weight: 900; text-align: center; line-height: 1.1; color: #fff; text-transform: uppercase; letter-spacing: -0.02em; }
.cta-headline em { font-style: normal; color: #e67e22; font-size: 1.35em; display: block; }
.book-cover { height: clamp(160px, 28vh, 240px); width: auto; object-fit: contain; border-radius: 4px; box-shadow: 0 16px 48px rgba(0,0,0,0.6); }
.cta-btn { display: inline-block; padding: 14px 36px; background: #e67e22; color: #fff; text-decoration: none; font-weight: 800; font-size: clamp(0.9rem, 2vw, 1.1rem); letter-spacing: 0.12em; text-transform: uppercase; border-radius: 2px; }
#slideDots { position: fixed; right: 27px; top: 50%; transform: translateY(-50%); display: flex; flex-direction: column; gap: 0; z-index: 300; align-items: center; }
.slide-dot { width: 20px; height: 20px; border-radius: 50%; background: transparent; border: none; cursor: pointer; padding: 0; flex-shrink: 0; display: flex; align-items: center; justify-content: center; position: relative; }
.slide-dot::after { content: ''; display: block; width: 9px; height: 9px; border-radius: 50%; background: rgba(120,120,120,0.35); transition: background 0.25s, transform 0.25s; }
.slide-dot:hover::after { background: #e67e22; transform: scale(1.3); }
.slide-dot.active::after { background: #e67e22; transform: scale(1.45); }
body.slide-dark .slide-dot::after { background: rgba(255,255,255,0.28); }
body.slide-dark .slide-dot.active::after { background: #e67e22; }
.slide-dot::before { content: attr(data-label); position: absolute; right: calc(100% + 8px); top: 50%; transform: translateY(-50%); background: rgba(20,20,20,0.78); color: #fff; font-size: 0.62rem; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; padding: 3px 8px; border-radius: 3px; white-space: nowrap; opacity: 0; pointer-events: none; transition: opacity 0.18s; font-family: inherit; }
.slide-dot:hover::before { opacity: 1; }
body.slide-dark .slide-dot::before { background: rgba(255,255,255,0.15); }
@media (max-width: 600px) {
  .slide { padding: 58px 16px 42px; gap: 10px; }
  .slide-img-wrap { margin-left: -16px; margin-right: -16px; width: calc(100% + 32px); max-width: calc(100% + 32px); flex: 0 1 auto; max-height: 44vh; }
  .slide-img { max-height: 44vh; }
  .slide-body { text-align: left; font-size: 1rem; }
  .slide-heading { text-align: left; font-size: 1.3rem; }
  .book-cover { height: clamp(120px,20vh,180px); }
  .cta-headline { font-size: 1.5rem; }
  .cta-headline em { font-size: 2.2rem; }
  #slideDots { transform: translate3d(18px,-50%,0); opacity: 0; pointer-events: none; transition: opacity 0.2s, transform 0.2s; }
  body.mobile-dots-visible #slideDots { opacity: 1; pointer-events: auto; transform: translate3d(0,-50%,0); }
}
@media (max-height: 600px) { .slide { padding-top: 52px; padding-bottom: 38px; gap: 8px; } }
html[lang="it"] [data-lang="en"] { display: none !important; }
html[lang="en"] [data-lang="it"] { display: none !important; }
.bb-wrap { display: flex; flex-direction: column; gap: 39px; width: 100%; max-width: 820px; }
.bb-def-row { display: flex; align-items: center; gap: 28px; }
.bb-term { font-size: clamp(1.47rem, 2.66vw, 1.82rem); font-weight: 900; color: #1a1a2e; min-width: 81px; }
.bb-desc { font-size: clamp(1.23rem, 2.1vw, 1.47rem); font-weight: 400; color: #555; flex: 1; }
.bb-box { width: 36px; height: 36px; border: 3.5px solid #e67e22; flex-shrink: 0; }
.bb-byte-row { display: flex; gap: 4px; }
.bb-sizes { display: flex; flex-direction: column; gap: 14px; width: 100%; max-width: 820px; border-top: 1px solid rgba(0,0,0,0.1); padding-top: 31px; }
.bb-size-row { display: grid; grid-template-columns: 294px 39px 1fr; align-items: center; font-size: clamp(1.12rem, 1.82vw, 1.33rem); color: #444; }
.bb-size-row strong { color: #1a1a2e; }
.bb-size-eq { color: #e67e22; font-weight: 900; text-align: center; }
@media (max-width: 600px) { .bb-size-row { grid-template-columns: 160px 22px 1fr; font-size: 0.85rem; } .bb-box { width: 24px; height: 24px; } }
.files-intro { font-size: clamp(1.4rem, 2.52vw, 1.68rem); font-weight: 400; max-width: 860px; text-align: left; width: 100%; line-height: 1.5; }
.files-cols { display: flex; gap: 73px; width: 100%; max-width: 860px; align-items: flex-start; }
.files-def-col { flex: 0 0 336px; display: flex; flex-direction: column; gap: 34px; }
.files-def-text { font-size: clamp(1.15rem, 1.89vw, 1.36rem); line-height: 1.65; color: #333; }
.files-chars { font-size: clamp(1.05rem, 1.61vw, 1.19rem); color: #888; display: flex; align-items: center; gap: 11px; }
.files-chars::after { content: '→'; color: #e67e22; font-size: 1.25em; font-weight: 900; }
.files-examples-col { flex: 1; display: flex; flex-direction: column; gap: 20px; }
.file-row { display: flex; align-items: center; gap: 22px; }
.file-name { font-size: clamp(1.19rem, 2.03vw, 1.4rem); color: #222; }
.file-ext { background: #ffff00; padding: 1px 3px; }
.file-cat { font-size: clamp(1.12rem, 1.82vw, 1.3rem); font-weight: 800; color: #27ae60; white-space: nowrap; }
@media (max-width: 600px) { .files-cols { flex-direction: column; gap: 20px; } .files-def-col { flex: none; } }
.slide--embed { padding: 0; overflow: hidden; }
.slide--embed iframe { width: 100%; height: 100%; border: none; display: block; }
.slide-dot--embed::after { border-radius: 2px; transform: rotate(45deg) scale(1.1); background: rgba(232,67,147,0.5); }
.slide-dot--embed:hover::after { background: #e84393; transform: rotate(45deg) scale(1.25); }
.slide-dot--embed.active::after { background: #e84393; transform: rotate(45deg) scale(1.2); }