Glas-kaart (glassmorphism)

<div class="gk-scene">
  <span class="gk-blob gk-blob--a" aria-hidden="true"></span>
  <span class="gk-blob gk-blob--b" aria-hidden="true"></span>
  <span class="gk-blob gk-blob--c" aria-hidden="true"></span>
  <article class="gk-card">
    <p class="gk-kicker">Live dashboard</p>
    <h3 class="gk-title">Inzicht zonder ruis</h3>
    <p class="gk-text">Een rustig paneel dat boven kleur zweeft. De achtergrond blijft zichtbaar, de tekst blijft leesbaar.</p>
    <a class="gk-btn" href="#">Bekijk details</a>
  </article>
</div>

/* Glas-kaart — prefix .gk- */
.gk-scene {
  --blob-a: #2E5BFF;
  --blob-b: #9B5CFF;
  --blob-c: #C6FF3D;
  --speed: 14s;
  position: relative;
  display: grid;
  place-items: center;
  width: min(100%, 440px);
  padding: 28px;
  isolation: isolate;
}

/* kleurblobs achter het glas */
.gk-blob {
  position: absolute;
  z-index: -1;
  border-radius: 50%;
  animation: gk-drift var(--speed) ease-in-out infinite alternate;
}

.gk-blob--a {
  width: 170px;
  height: 170px;
  top: 0;
  left: 4%;
  background: var(--blob-a);
}

.gk-blob--b {
  width: 140px;
  height: 140px;
  bottom: 0;
  right: 6%;
  background: var(--blob-b);
  animation-duration: calc(var(--speed) * 1.3);
  animation-direction: alternate-reverse;
}

.gk-blob--c {
  width: 80px;
  height: 80px;
  top: 42%;
  right: 30%;
  background: var(--blob-c);
  animation-duration: calc(var(--speed) * .8);
}

@keyframes gk-drift {
  to { transform: translate(40px, 24px) scale(1.15); }
}

/* het glaspaneel */
.gk-card {
  --blur: 18px;
  --radius: 20px;
  --accent: #C6FF3D;
  position: relative;
  overflow: hidden;
  width: 100%;
  max-width: 340px;
  padding: 24px 26px 26px;
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, .22);
  background: rgba(18, 18, 24, .35);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .25), 0 20px 40px -20px rgba(0, 0, 0, .6);
  color: #F9F8F6;
  -webkit-backdrop-filter: blur(var(--blur)) saturate(160%);
  backdrop-filter: blur(var(--blur)) saturate(160%);
}

/* fallback zonder backdrop-filter */
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .gk-card { background: rgba(18, 18, 24, .92); }
}

/* glansstreep */
.gk-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(115deg, transparent 35%, rgba(255, 255, 255, .28) 50%, transparent 65%);
  transform: translateX(-110%);
  transition: transform .8s cubic-bezier(.2, .7, .2, 1);
  pointer-events: none;
}

.gk-card:hover::before,
.gk-card:focus-within::before {
  transform: translateX(110%);
}

.gk-kicker {
  margin: 0 0 8px;
  font: 600 12px/1 ui-monospace, Menlo, Consolas, monospace;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--accent);
}

.gk-title {
  margin: 0 0 8px;
  font: 800 24px/1.1 "Arial Black", "Helvetica Neue", Impact, system-ui, sans-serif;
}

.gk-text {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.5;
  color: rgba(249, 248, 246, .88);
}

.gk-btn {
  display: inline-flex;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--accent);
  color: #0C0C0D;
  font-weight: 700;
  font-size: 14px;
  text-decoration: none;
  transition: transform .2s ease;
}

.gk-btn:hover {
  transform: translateY(-2px);
}

.gk-btn:focus-visible {
  outline: 2px solid #F9F8F6;
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .gk-blob { animation: none; }
  .gk-card::before {
    transform: none;
    opacity: 0;
    transition: opacity .3s ease;
  }
  .gk-card:hover::before,
  .gk-card:focus-within::before {
    transform: none;
    opacity: 1;
  }
  .gk-btn { transition: none; }
  .gk-btn:hover { transform: none; }
}