System Scan Button with Animated Scan Line

<style>
  /* 22. SCANNER */
  .btn-scan {
    position: relative;              /* so .scan-line & spotlight are positioned inside */
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: transparent;
    border-radius: 999px;
    overflow: hidden;
    border: 1px solid rgba(0, 255, 0, 0.3);
    color: rgba(0, 255, 0, 0.8);
    font-size: 0.8rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
  }

  .btn-size-2 {
    width: 100%;                     /* your original intent for full-width button */
  }

  .scan-line {
    position: absolute;
    top: 0;
    left: -50%;
    width: 100%;
    height: 100%;
    background: linear-gradient(
      90deg,
      transparent,
      rgba(0, 255, 0, 0.4),
      transparent
    );
    animation: scan 2s infinite ease-in-out;
    transform: skewX(-20deg);
    pointer-events: none;
  }

  @keyframes scan {
    0%   { left: -100%; }
    100% { left: 200%; }
  }

  /* ================================================================
     Spotlight overlay
  =================================================================*/
  .btn-spotlight {
    position: relative;
  }

  .spotlight-beam {
    position: absolute;
    inset: 0;
    background:
      radial-gradient(circle at 30% -10%,
        rgba(0, 255, 0, 0.35),
        transparent 55%);
    opacity: 0;
    mix-blend-mode: screen;
    transition: opacity 0.25s ease-out;
    pointer-events: none;
    z-index: 1;
  }

  /* Missing line you mentioned */
  .btn-spotlight:hover .spotlight-beam {
    opacity: 1;
  }

  /* 3D / other utilities you already had (kept as-is) */
  .preserve-3d { transform-style: preserve-3d; }
  .backface-hidden { backface-visibility: hidden; }
  .persp-1000 { perspective: 1000px; }
  .persp-2000 { perspective: 2000px; }

  .rotate-x-90 { transform: rotateX(90deg); }
  .rotate-y-180 { transform: rotateY(180deg); }
  .-rotate-x-90 { transform: rotateX(-90deg); }
  .rotate-x-110 { transform: rotateX(110deg); }
  .-rotate-y-140 { transform: rotateY(-140deg); }

  .group:hover .group-hover\:rotate-x-\[110deg\] { transform: rotateX(110deg); }
  .group:hover .group-hover\:rotate-y-\[-140deg\] { transform: rotateY(-140deg); }

  @keyframes scan-line-3d {
    0%   { transform: translateX(-100%); }
    100% { transform: translateX(500%); }
  }

  @keyframes wiggle {
    0%, 100% { transform: rotate(0deg); }
    25%      { transform: rotate(-15deg); }
    75%      { transform: rotate(15deg); }
  }

  @keyframes pulse-ring {
    0%   { transform: scale(0.8); opacity: 0.5; }
    100% { transform: scale(2); opacity: 0; }
  }

  .animate-scan-3d,
  .animate-scan {
    animation: scan-line-3d 2.5s cubic-bezier(0.4, 0, 0.2, 1) infinite;
  }

  .group:hover .animate-bell-wiggle {
    animation: wiggle 0.5s ease-in-out infinite;
  }

  .group:hover .animate-pulse-ring {
    animation: pulse-ring 1.5s cubic-bezier(0, 0, 0.2, 1) infinite;
  }

  .btn-size-3 {
    width: 100%;
  }
</style>

<div class="btn-wrapper" style="max-width: 260px;">
 

  <button class="btn-scan btn-spotlight btn-size-2">
    <!-- Spotlight overlay -->
    <div class="spotlight-beam"></div>

    <!-- Scan line -->
    <div class="scan-line"></div>

    <!-- Label -->
    <span style="position:relative; z-index:2;">
      SYSTEM SCAN
    </span>
  </button>
</div>