/* ==========================================================================
   3D Holographic NFT Card Collector System (立体 3D 悬浮卡牌 & 镭射反光动效)
   ========================================================================== */

.cards-showcase-section {
  padding: 100px 0 110px;
  position: relative;
}

.cards-container-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
  perspective: 1400px;
  margin-top: 40px;
}

/* Outer Wrapper that holds 3D perspective */
.nft-card-wrapper {
  perspective: 1400px;
  position: relative;
  min-height: 580px;
  cursor: pointer;
}

/* Flippable Card Inner */
.nft-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 0.65s cubic-bezier(0.23, 1, 0.32, 1);
  border-radius: 18px;
  will-change: transform;
}

/* Flipped state */
.nft-card-wrapper.is-flipped .nft-card-inner {
  transform: rotateY(180deg);
}

/* Card Faces */
.card-face {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: 18px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 24px 20px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.75), 0 0 0 1px rgba(255, 255, 255, 0.1);
  background: #0b0f19;
  transition: box-shadow 0.3s ease;
}

.card-face-back {
  transform: rotateY(180deg);
  background: #090d16;
}

/* ==========================================================================
   Holographic Foil & Laser Sheen Overlays
   ========================================================================== */
.holo-foil-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 5;
  border-radius: 18px;
  opacity: 0;
  mix-blend-mode: color-dodge;
  transition: opacity 0.3s ease;
  background-size: 200% 200%;
  background-position: 50% 50%;
}

.nft-card-wrapper:hover .holo-foil-overlay {
  opacity: 0.65;
}

/* Special SSR Rainbow Holographic Foil */
.card-ssr .holo-foil-overlay {
  background-image: linear-gradient(
    115deg,
    transparent 0%,
    rgba(255, 0, 128, 0.5) 15%,
    rgba(0, 243, 255, 0.5) 30%,
    rgba(255, 230, 0, 0.5) 45%,
    rgba(0, 255, 128, 0.5) 60%,
    rgba(170, 0, 255, 0.5) 75%,
    transparent 100%
  );
  filter: brightness(1.2) contrast(1.1);
}

.card-ur .holo-foil-overlay {
  background-image: linear-gradient(
    135deg,
    transparent 0%,
    rgba(255, 0, 60, 0.6) 20%,
    rgba(255, 180, 0, 0.6) 40%,
    rgba(0, 243, 255, 0.6) 65%,
    rgba(255, 0, 120, 0.6) 85%,
    transparent 100%
  );
}

.card-sr .holo-foil-overlay {
  background-image: linear-gradient(
    125deg,
    transparent 0%,
    rgba(189, 0, 255, 0.45) 25%,
    rgba(0, 243, 255, 0.5) 50%,
    rgba(255, 0, 128, 0.45) 75%,
    transparent 100%
  );
}

.card-r .holo-foil-overlay {
  background-image: linear-gradient(
    120deg,
    transparent 0%,
    rgba(0, 200, 255, 0.35) 40%,
    rgba(100, 230, 255, 0.45) 60%,
    transparent 100%
  );
}

/* Metallic Glare highlight (follows mouse) */
.card-glare {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 6;
  border-radius: 18px;
  background: radial-gradient(
    circle 220px at var(--mouse-x, 50%) var(--mouse-y, 50%),
    rgba(255, 255, 255, 0.35),
    transparent 80%
  );
  opacity: 0;
  transition: opacity 0.25s ease;
}

.nft-card-wrapper:hover .card-glare {
  opacity: 1;
}

/* ==========================================================================
   Rarity Tiers Custom Styling
   ========================================================================== */

/* R 级 - 平民探针 (Bronze/Steel Blue) */
.card-r {
  border: 1px solid rgba(0, 200, 255, 0.3);
}
.card-r:hover {
  border-color: var(--r-tier-glow);
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.8), 0 0 25px rgba(0, 200, 255, 0.25);
}
.card-r .tier-badge {
  background: rgba(0, 200, 255, 0.15);
  border: 1px solid var(--r-tier-glow);
  color: #38bdf8;
}

/* SR 级 - 流媒体特攻 (Neon Purple / Violet) */
.card-sr {
  border: 1px solid rgba(189, 0, 255, 0.4);
}
.card-sr:hover {
  border-color: var(--sr-tier-glow);
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.8), 0 0 35px rgba(189, 0, 255, 0.35);
}
.card-sr .tier-badge {
  background: rgba(189, 0, 255, 0.2);
  border: 1px solid var(--sr-tier-glow);
  color: #e879f9;
}

/* SSR 级 - 千兆 IEPL 幻影专线 (Holographic Gold / Rainbow Sheen) */
.card-ssr {
  border: 1.5px solid rgba(255, 183, 0, 0.5);
  position: relative;
}
.card-ssr::after {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: 20px;
  background: linear-gradient(90deg, #ff007b, #00f3ff, #ffb700, #bd00ff, #ff007b);
  background-size: 400% 400%;
  z-index: -1;
  animation: borderGlowRainbow 4s ease infinite;
  opacity: 0.6;
}
@keyframes borderGlowRainbow {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}
.card-ssr:hover {
  box-shadow: 0 25px 65px rgba(0, 0, 0, 0.85), 0 0 45px rgba(255, 183, 0, 0.5);
}
.card-ssr .tier-badge {
  background: linear-gradient(135deg, #ffe259, #ffa751);
  color: #000;
  font-weight: 800;
  border: none;
  box-shadow: 0 0 15px rgba(255, 183, 0, 0.6);
}

/* UR 级 - 极客终极领航旗舰 (Matrix Obsidian Crimson) */
.card-ur {
  border: 1.5px solid rgba(255, 0, 60, 0.6);
  position: relative;
}
.card-ur::after {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: 20px;
  background: linear-gradient(135deg, #ff003c, #ff9900, #ff007f);
  background-size: 200% 200%;
  z-index: -1;
  animation: borderGlowCrimson 3s ease infinite;
  opacity: 0.7;
}
@keyframes borderGlowCrimson {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}
.card-ur:hover {
  box-shadow: 0 25px 70px rgba(0, 0, 0, 0.9), 0 0 50px rgba(255, 0, 60, 0.55);
}
.card-ur .tier-badge {
  background: #ff003c;
  color: #fff;
  font-weight: 800;
  border: none;
  box-shadow: 0 0 20px #ff003c;
}

/* ==========================================================================
   Card Header (NFT Mint, Serial, Badge)
   ========================================================================== */
.card-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.mint-serial {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: #64748b;
  letter-spacing: 1px;
}

.tier-badge {
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 800;
  padding: 3px 10px;
  border-radius: 4px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

/* Card Artwork / Visual Representation */
.card-art-box {
  width: 100%;
  height: 150px;
  border-radius: 10px;
  background: rgba(0, 0, 0, 0.45);
  border: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  margin-bottom: 16px;
}

.card-art-box::before {
  content: '';
  position: absolute;
  width: 120%;
  height: 120%;
  background: radial-gradient(circle, rgba(0, 243, 255, 0.15) 0%, transparent 65%);
}

.card-r .card-art-box::before { background: radial-gradient(circle, rgba(0, 200, 255, 0.2) 0%, transparent 70%); }
.card-sr .card-art-box::before { background: radial-gradient(circle, rgba(189, 0, 255, 0.25) 0%, transparent 70%); }
.card-ssr .card-art-box::before { background: radial-gradient(circle, rgba(255, 183, 0, 0.3) 0%, transparent 70%); }
.card-ur .card-art-box::before { background: radial-gradient(circle, rgba(255, 0, 60, 0.35) 0%, transparent 70%); }

.art-emblem {
  font-size: 3.5rem;
  z-index: 2;
  filter: drop-shadow(0 0 15px rgba(255, 255, 255, 0.3));
  transition: transform 0.3s ease;
}
.nft-card-wrapper:hover .art-emblem {
  transform: scale(1.1) translateY(-3px);
}

.art-watermark {
  position: absolute;
  bottom: 6px;
  right: 8px;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: rgba(255, 255, 255, 0.25);
  letter-spacing: 1px;
}

/* Card Body Information */
.card-title-group {
  margin-bottom: 12px;
}

.card-name {
  font-family: var(--font-display);
  font-size: 1.28rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: 0.5px;
  line-height: 1.2;
}

.card-subtext {
  font-size: 0.78rem;
  color: #94a3b8;
  margin-top: 4px;
}

.card-stat-matrix {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: 8px;
  padding: 10px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
}

.stat-item {
  display: flex;
  flex-direction: column;
}
.stat-item .lbl {
  font-size: 0.65rem;
  color: #64748b;
  text-transform: uppercase;
}
.stat-item .val {
  font-size: 0.88rem;
  font-weight: 700;
  color: #e2e8f0;
}

.card-price-box {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  padding: 10px 0;
  border-top: 1px dashed rgba(255, 255, 255, 0.1);
  margin-top: auto;
}

.price-currency {
  font-size: 0.85rem;
  color: var(--neon-cyan);
  font-family: var(--font-mono);
}

.price-amount {
  font-family: var(--font-display);
  font-size: 1.7rem;
  font-weight: 800;
  color: #fff;
}

.price-period {
  font-size: 0.75rem;
  color: #64748b;
  font-family: var(--font-mono);
}

.card-flip-prompt {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 8px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: #94a3b8;
  margin-top: 10px;
  transition: all var(--transition-fast);
}

.nft-card-wrapper:hover .card-flip-prompt {
  background: rgba(0, 243, 255, 0.15);
  color: #fff;
  border-color: var(--neon-cyan);
}

/* ==========================================================================
   Card Backside Layout & Technical Specs
   ========================================================================== */
.back-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.back-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
}

.btn-flip-back {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #94a3b8;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 3px 8px;
  border-radius: 4px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-flip-back:hover {
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  border-color: #fff;
}

.back-specs-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  margin-bottom: 18px;
}

.back-specs-list li {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  color: #94a3b8;
}

.back-specs-list li strong {
  color: #fff;
}

.back-features-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 18px;
}

.spec-pill {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 3px 8px;
  border-radius: 4px;
  background: rgba(0, 243, 255, 0.08);
  border: 1px solid rgba(0, 243, 255, 0.2);
  color: var(--neon-cyan);
}

.back-cta-box {
  margin-top: auto;
}

.btn-card-checkout {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px;
  border-radius: 8px;
  text-decoration: none;
  font-family: var(--font-display);
  font-size: 0.98rem;
  font-weight: 800;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: #000;
  background: var(--neon-cyan);
  border: none;
  cursor: pointer;
  box-shadow: 0 0 20px var(--neon-cyan-glow);
  transition: all var(--transition-fast);
}

.card-r .btn-card-checkout {
  background: #38bdf8;
  box-shadow: 0 0 20px rgba(56, 189, 248, 0.4);
}
.card-sr .btn-card-checkout {
  background: #bd00ff;
  color: #fff;
  box-shadow: 0 0 20px rgba(189, 0, 255, 0.5);
}
.card-ssr .btn-card-checkout {
  background: linear-gradient(135deg, #ffd700, #ff8800);
  color: #000;
  box-shadow: 0 0 30px rgba(255, 215, 0, 0.6);
}
.card-ur .btn-card-checkout {
  background: linear-gradient(135deg, #ff003c, #ff5500);
  color: #fff;
  box-shadow: 0 0 30px rgba(255, 0, 60, 0.7);
}

.btn-card-checkout:hover {
  transform: translateY(-2px);
  filter: brightness(1.2);
}

/* Responsive adjustments */
@media (max-width: 1200px) {
  .cards-container-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
}

@media (max-width: 640px) {
  .cards-container-grid {
    grid-template-columns: 1fr;
  }
  .nft-card-wrapper {
    min-height: 520px;
  }
}