/* ==========================================================================
   Realistic 3D Book CSS
   Reference: "Design Engineering at Vercel" style mockup
   ========================================================================== */

/* The card acts as the perspective camera */
.product-card, .book-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  perspective: 1500px;
  perspective-origin: 50% 50%;
  cursor: pointer;
  text-decoration: none;
  color: var(--ink);
}

.book-container {
  margin-bottom: 24px;
}

/* The physical book block */
.book-3d {
  width: 100%;
  max-width: 220px;
  aspect-ratio: 3 / 4;
  position: relative;
  transform-style: preserve-3d;
  /* At rest: completely flat facing forward */
  transform: rotateY(0deg) rotateX(0deg) rotateZ(0deg) translateZ(0);
  transition: transform 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.product-card:hover .book-3d,
.book-container:hover .book-3d {
  /* On hover: swing right to reveal the left spine and right pages */
  transform: rotateY(-25deg) rotateX(8deg) rotateZ(-1deg) translateZ(30px) scale(1.05);
}

/* ---- Front Cover ---- */
.book-cover {
  position: absolute;
  inset: 0;
  border-radius: 2px 4px 4px 2px;
  transform-style: preserve-3d;
  /* Book depth = 36px total. Half is 18px */
  transform: translateZ(18px);
  background: var(--book-color, #c0392b);
  overflow: hidden;
}

/* Base image styling */
.book-cover-img,
.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  z-index: 1;
  position: relative;
}

/* Lighting: Hinge line (indentation near spine) and cover glare */
.book-cover::after {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 10;
  pointer-events: none;
  background: 
    /* Hinge indentation */
    linear-gradient(to right, 
      rgba(255,255,255,0) 2px, 
      rgba(255,255,255,0.4) 3px, 
      rgba(0,0,0,0.1) 4px, 
      rgba(255,255,255,0) 6px,
      rgba(255,255,255,0) 12px,
      /* Glare across the cover */
      rgba(255,255,255,0.2) 15px,
      rgba(255,255,255,0) 30px,
      rgba(0,0,0,0.05) 100%
    );
  border-radius: inherit;
  box-shadow: inset 1px 0 3px rgba(255,255,255,0.3), inset -1px 0 2px rgba(0,0,0,0.1);
}

/* Fine linen/canvas texture */
.book-texture {
  position: absolute;
  inset: 0;
  z-index: 5;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(0deg, rgba(255,255,255,0.03) 0, rgba(255,255,255,0.03) 1px, transparent 1px, transparent 4px),
    repeating-linear-gradient(90deg, rgba(255,255,255,0.03) 0, rgba(255,255,255,0.03) 1px, transparent 1px, transparent 4px);
  mix-blend-mode: overlay;
}

/* ---- Spine ---- */
.book-spine {
  position: absolute;
  top: 0; 
  left: -18px; /* half of 36px thickness */
  width: 36px;
  height: 100%;
  background: color-mix(in srgb, var(--book-color, #c0392b) 80%, #000 20%);
  transform: rotateY(-90deg);
  border-radius: 4px 0 0 4px;
  transform-origin: center;
  box-shadow: 
    inset -2px 0 6px rgba(0,0,0,0.3),
    inset 2px 0 5px rgba(255,255,255,0.1);
  overflow: hidden;
}

/* Spine lighting */
.book-spine::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to right, 
    rgba(255,255,255,0.1) 0%, 
    rgba(255,255,255,0.2) 20%, 
    rgba(0,0,0,0.15) 80%, 
    rgba(0,0,0,0.3) 100%
  );
  pointer-events: none;
}

/* ---- Back Cover ---- */
.book-back {
  position: absolute;
  inset: 0;
  border-radius: 4px 2px 2px 4px;
  transform: rotateY(180deg) translateZ(18px);
  background: var(--book-color, #c0392b);
  box-shadow: inset -4px 0 10px rgba(0,0,0,0.15);
}

/* ---- Right Pages (Foredge) ---- */
.book-pages {
  position: absolute;
  top: 1%;
  right: -18px;
  width: 36px; 
  height: 98%;
  background: #fdfdfc;
  transform: rotateY(90deg);
  transform-origin: center;
  /* Render individual pages using fine lines */
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0, transparent 2px,
    rgba(0,0,0,0.05) 2px, rgba(0,0,0,0.05) 3px
  );
  border-radius: 0 3px 3px 0;
  box-shadow: 
    inset 3px 0 6px rgba(0,0,0,0.1),
    inset -1px 0 2px rgba(0,0,0,0.05);
}

/* ---- Top Pages (Head) - For extra 3D realism ---- */
.book-pages-top {
  position: absolute;
  top: -18px;
  left: 2px; /* compensate for spine rounding */
  width: calc(100% - 4px); /* slightly narrower than cover */
  height: 36px;
  background: #fdfdfc;
  transform: rotateX(90deg);
  transform-origin: center;
  background-image: repeating-linear-gradient(
    to right,
    transparent 0, transparent 2px,
    rgba(0,0,0,0.05) 2px, rgba(0,0,0,0.05) 3px
  );
  border-radius: 2px;
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.05);
}

/* ---- Bottom Pages (Tail) ---- */
.book-pages-bottom {
  position: absolute;
  bottom: -18px;
  left: 2px;
  width: calc(100% - 4px);
  height: 36px;
  background: #fdfdfc;
  transform: rotateX(-90deg);
  transform-origin: center;
  background-image: repeating-linear-gradient(
    to right,
    transparent 0, transparent 2px,
    rgba(0,0,0,0.05) 2px, rgba(0,0,0,0.05) 3px
  );
  border-radius: 2px;
  box-shadow: inset 0 -2px 4px rgba(0,0,0,0.05);
}

/* ---- Realistic Shadow on the Floor ---- */
.book-shadow-el {
  width: 85%;
  height: 12px;
  margin: -6px auto 16px; /* pull up slightly under book */
  background: radial-gradient(ellipse at 50% 50%, rgba(0,0,0,0.15) 0%, rgba(0,0,0,0.02) 60%, transparent 80%);
  filter: blur(4px);
  transition: all 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
  /* Flat shadow for flat book */
  transform: translateX(0) translateY(4px) scale(0.9);
}

.product-card:hover .book-shadow-el,
.book-container:hover .book-shadow-el {
  width: 90%;
  transform: translateX(20px) translateY(18px) scale(1);
  filter: blur(8px);
  opacity: 0.7;
  background: radial-gradient(ellipse at 50% 50%, rgba(0,0,0,0.25) 0%, rgba(0,0,0,0.05) 60%, transparent 80%);
}

/* Fallback cover styling */
.book-cover-placeholder {
  width: 100%; height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  padding: clamp(10px, 8%, 18px);
  box-sizing: border-box;
}

.book-cover-placeholder .cover-title {
  font-family: var(--font-display);
  font-size: clamp(12px, 1.1em, 17px);
  font-weight: 700;
  color: #fff;
  line-height: 1.3;
  max-width: 85%;
  word-break: break-word;
  text-shadow: 0 1px 3px rgba(0,0,0,0.3);
  position: relative;
  z-index: 20;
}