/* styles.css — Plasticology 2nd Edition */
:root {
  --primary: #7c3aed;
  --primary2: #0891b2;
  --primary3: #db2777;
}

* { box-sizing: border-box; }

body {
  background: #fff;
  overflow-x: hidden;
  font-family: 'Cairo', sans-serif;
}

/* ── Sticky nav ─────────────────────────────────────────────────── */
#anchor-nav {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid #e2e8f0;
  box-shadow: 0 1px 4px rgba(0,0,0,0.06);
}
#anchor-nav .inner {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .5rem;
  height: 48px;
}
#anchor-nav .nav-links {
  display: flex;
  gap: .25rem;
  overflow-x: auto;
  scrollbar-width: none;
}
#anchor-nav .nav-links::-webkit-scrollbar { display: none; }
#anchor-nav .nav-links button {
  white-space: nowrap;
  padding: 6px 12px;
  border-radius: 8px;
  font-size: .75rem;
  font-weight: 700;
  color: #64748b;
  transition: all .2s;
}
#anchor-nav .nav-links button:hover { background: #f1f5f9; color: #0f172a; }
#anchor-nav .nav-ctas { display: flex; gap: .5rem; flex-shrink: 0; }
.btn-order {
  display: inline-flex; align-items: center; gap: .35rem;
  background: #22c55e; color: #fff; font-weight: 900; font-size: .75rem;
  padding: 7px 14px; border-radius: 10px; transition: background .2s;
  white-space: nowrap;
}
.btn-order:hover { background: #16a34a; }
.btn-platform {
  display: inline-flex; align-items: center; gap: .35rem;
  background: #2563eb; color: #fff; font-weight: 900; font-size: .75rem;
  padding: 7px 14px; border-radius: 10px; transition: background .2s;
  white-space: nowrap;
}
.btn-platform:hover { background: #1d4ed8; }

/* ── Hero ───────────────────────────────────────────────────────── */
#hero {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 60%, #0f172a 100%);
  overflow: hidden;
  position: relative;
}
.hero-blob {
  position: absolute; border-radius: 50%; filter: blur(80px);
  pointer-events: none; opacity: .25;
}

/* Book float animations */
@keyframes float0 {
  0%,100% { transform: translateY(0px); }
  50%      { transform: translateY(-12px); }
}
@keyframes float1 {
  0%,100% { transform: translateY(0px); }
  50%      { transform: translateY(-18px); }
}
@keyframes float2 {
  0%,100% { transform: translateY(0px); }
  50%      { transform: translateY(-10px); }
}
.book-float-0 { animation: float0 4s ease-in-out infinite; }
.book-float-1 { animation: float1 4.5s ease-in-out infinite .3s; }
.book-float-2 { animation: float2 5s ease-in-out infinite .6s; }

/* ── Volume cards ───────────────────────────────────────────────── */
.vol-card {
  background: #fff;
  border-radius: 24px;
  border: 1px solid #e2e8f0;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
  transition: box-shadow .3s, transform .3s;
  display: flex; flex-direction: column;
}
.vol-card:hover { box-shadow: 0 12px 32px rgba(0,0,0,.1); transform: translateY(-2px); }
.vol-card-cover img {
  transition: transform .5s;
}
.vol-card-cover:hover img { transform: scale(1.05); }
.action-btn {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  padding: 10px; border-radius: 12px; border-width: 2px; border-style: solid;
  font-size: .6875rem; font-weight: 900; transition: opacity .2s;
  cursor: pointer; background: transparent;
}
.action-btn:hover { opacity: .75; }
.chapter-row {
  display: flex; align-items: flex-start; gap: 8px;
  padding: 6px 0; border-bottom: 1px solid #f8fafc; font-size: .75rem; color: #475569;
}
.chapter-row:last-child { border-bottom: none; }

/* ── Platform features ──────────────────────────────────────────── */
.feat-card {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: 16px; padding: 16px;
  transition: background .2s;
}
.feat-card:hover { background: rgba(255,255,255,.1); }

/* ── Curriculum rows ────────────────────────────────────────────── */
.curr-row {
  display: flex; align-items: center; gap: 16px;
  padding: 14px 16px; border-radius: 12px; border: 1px solid #e2e8f0;
  background: #fff; transition: border-color .2s, box-shadow .2s;
}
.curr-row:hover { border-color: #cbd5e1; box-shadow: 0 2px 8px rgba(0,0,0,.06); }
.curr-row.coming { opacity: .55; background: #f8fafc; }

/* ── Reviews ────────────────────────────────────────────────────── */
.review-card {
  background: #fff; border-radius: 16px;
  border: 1px solid #e2e8f0; padding: 20px;
  box-shadow: 0 1px 4px rgba(0,0,0,.04);
  transition: box-shadow .2s;
  break-inside: avoid;
}
.review-card:hover { box-shadow: 0 4px 16px rgba(0,0,0,.08); }

/* ── FAQ ────────────────────────────────────────────────────────── */
.faq-item {
  background: #fff; border-radius: 16px;
  border: 1px solid #e2e8f0; overflow: hidden;
  box-shadow: 0 1px 4px rgba(0,0,0,.04);
}
.faq-trigger {
  width: 100%; display: flex; align-items: flex-start;
  justify-content: space-between; gap: 16px;
  padding: 18px 20px; text-align: left; cursor: pointer;
  transition: background .15s;
}
.faq-trigger:hover { background: #f8fafc; }
.faq-body {
  display: none; padding: 0 20px 18px;
  border-top: 1px solid #f1f5f9;
}
.faq-body.open { display: block; }
.faq-chevron { transition: transform .2s; flex-shrink: 0; margin-top: 2px; }
.faq-chevron.open { transform: rotate(180deg); }

/* ── Community links ────────────────────────────────────────────── */
.comm-link {
  background: #fff; border: 1px solid #e2e8f0; border-radius: 16px;
  padding: 16px; display: flex; flex-direction: column;
  align-items: center; gap: 8px; text-align: center;
  transition: box-shadow .2s, border-color .2s;
}
.comm-link:hover { box-shadow: 0 4px 12px rgba(0,0,0,.08); border-color: #cbd5e1; }

/* ── PDF Viewer modal ───────────────────────────────────────────── */
#pdf-viewer {
  display: none;
  position: fixed; inset: 0; z-index: 300;
  background: rgba(0,0,0,.92);
  backdrop-filter: blur(4px);
  flex-direction: column;
}
#pdf-viewer.open { display: flex; }

#pdf-viewer .viewer-header {
  display: flex; align-items: center;
  justify-content: space-between;
  gap: 12px; padding: 10px 16px;
  background: rgba(0,0,0,.6);
  border-bottom: 1px solid rgba(255,255,255,.1);
  flex-shrink: 0;
}
.viewer-tabs {
  display: flex; background: rgba(255,255,255,.1);
  padding: 4px; border-radius: 12px; gap: 4px;
}
.viewer-tab {
  display: flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-radius: 8px;
  font-size: .75rem; font-weight: 700; color: rgba(255,255,255,.7);
  transition: all .15s; cursor: pointer; border: none;
}
.viewer-tab.active { background: #fff; color: #0f172a; }
.viewer-tab:not(.active):hover { color: #fff; }
.viewer-zoom-btns {
  display: flex; align-items: center; gap: 4px;
}
.zoom-btn {
  padding: 6px; background: rgba(255,255,255,.1);
  border-radius: 8px; color: #fff; border: none; cursor: pointer;
  transition: background .15s; display: flex; align-items: center;
}
.zoom-btn:hover { background: rgba(255,255,255,.2); }
.zoom-btn:disabled { opacity: .4; cursor: default; }
.close-btn {
  padding: 8px; background: rgba(255,255,255,.1);
  border-radius: 50%; color: #fff; border: none; cursor: pointer;
  transition: background .15s; display: flex; align-items: center;
}
.close-btn:hover { background: #ef4444; }

#pdf-canvas-area {
  flex: 1; overflow: auto; background: #1e293b;
  display: flex; justify-content: center; align-items: flex-start;
  padding: 16px 8px;
}
#pdf-canvas { display: block; box-shadow: 0 20px 60px rgba(0,0,0,.5); }

#pdf-loading {
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 12px; margin-top: 80px; color: rgba(255,255,255,.4);
}
#pdf-error {
  display: none; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 8px; margin-top: 80px; text-align: center; padding: 16px;
}

.viewer-footer {
  flex-shrink: 0; display: flex; align-items: center;
  justify-content: space-between; gap: 12px;
  padding: 10px 16px;
  background: rgba(0,0,0,.6);
  border-top: 1px solid rgba(255,255,255,.1);
}
.page-nav-btn {
  display: flex; align-items: center; gap: 4px;
  padding: 6px 12px; background: rgba(255,255,255,.1);
  border-radius: 8px; color: #fff; font-size: .75rem; font-weight: 700;
  border: none; cursor: pointer; transition: background .15s;
}
.page-nav-btn:hover { background: rgba(255,255,255,.2); }
.page-nav-btn:disabled { opacity: .4; cursor: default; }
#page-counter { color: rgba(255,255,255,.7); font-size: .75rem; font-weight: 700; min-width: 64px; text-align: center; }

/* Spinner */
@keyframes spin { to { transform: rotate(360deg); } }
.spinner {
  width: 36px; height: 36px; border: 3px solid rgba(255,255,255,.15);
  border-top-color: rgba(255,255,255,.6); border-radius: 50%;
  animation: spin 1s linear infinite;
}

/* ── Serial code callout ────────────────────────────────────────── */
.serial-callout {
  border: 2px solid #f59e0b; border-radius: 16px;
  background: linear-gradient(to right, #fffbeb, #fef3c7, #fffbeb);
  overflow: hidden; position: relative;
}
.serial-callout::before {
  content: 'NEW'; position: absolute; top: 0; left: 0;
  background: #f59e0b; color: #1c1917;
  font-size: .6rem; font-weight: 900; letter-spacing: .05em;
  padding: 2px 8px; border-bottom-right-radius: 8px;
}

/* ── Back to top ────────────────────────────────────────────────── */
#backToTop {
  position: fixed; bottom: 24px; right: 24px; z-index: 50;
  background: #7c3aed; color: #fff;
  width: 44px; height: 44px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 4px 14px rgba(124,58,237,.4);
  opacity: 0; transform: translateY(20px);
  transition: opacity .3s, transform .3s;
  border: none; cursor: pointer;
}
#backToTop.visible { opacity: 1; transform: translateY(0); }

/* ── Progress bar ───────────────────────────────────────────────── */
#progress-bar {
  position: fixed; top: 0; left: 0; height: 3px; width: 0%;
  z-index: 9999; pointer-events: none;
  background: linear-gradient(to right, #7c3aed, #db2777, #f59e0b);
  transition: width .1s linear;
}

/* ── Scroll reveal ──────────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .6s ease, transform .6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Video section ──────────────────────────────────────────────── */
.video-wrapper {
  position: relative;
  padding-top: 56.25%;
  background: #0f172a;
}
.video-wrapper iframe {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  border: none;
}

/* ── Floating WhatsApp button ───────────────────────────────────── */
#float-whatsapp {
  position: fixed; bottom: 80px; right: 24px; z-index: 50;
  display: flex; align-items: center; gap: 8px;
  background: #22c55e; color: #fff;
  padding: 12px 18px; border-radius: 50px;
  font-weight: 900; font-size: .8125rem;
  box-shadow: 0 6px 20px rgba(34,197,94,.4);
  transition: transform .2s, box-shadow .2s, opacity .3s;
  opacity: 0; transform: translateY(12px);
  pointer-events: none;
}
#float-whatsapp.visible {
  opacity: 1; transform: translateY(0); pointer-events: auto;
}
#float-whatsapp:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(34,197,94,.5);
}
#float-whatsapp svg {
  width: 18px; height: 18px; flex-shrink: 0;
}

/* ── Mobile hero — single cover on small screens ────────────────── */
@media (max-width: 480px) {
  #hero-covers { width: 220px !important; height: 260px !important; }
  #hero-covers > div:nth-child(1),
  #hero-covers > div:nth-child(3) { display: none; }
  #hero-covers > div:nth-child(2) {
    transform: translateX(-50%) rotate(0deg) !important;
  }
  #hero-covers > div:nth-child(2) img { height: 240px !important; }
}

/* ── Utility ────────────────────────────────────────────────────── */
.no-scrollbar { scrollbar-width: none; }
.no-scrollbar::-webkit-scrollbar { display: none; }