Prijs-kaart met acid accent

<article class="pk-card">
  <span class="pk-ribbon">Populair</span>
  <p class="pk-plan">Groei</p>
  <p class="pk-price"><span class="pk-from">Vanaf</span> €—<span class="pk-per">/maand</span></p>
  <ul class="pk-list">
    <li>Maatwerk webdesign</li>
    <li>Animaties & microinteracties</li>
    <li>Technische SEO-basis</li>
  </ul>
  <a class="pk-btn" href="#">Plan een gesprek</a>
</article>

/* Prijs-kaart — prefix .pk- */
.pk-card {
  --ink: #0C0C0D;
  --paper: #F9F8F6;
  --accent: #C6FF3D;
  --lift: 6px;
  --speed: 240ms;
  position: relative;
  overflow: hidden;
  width: min(100%, 320px);
  padding: 26px 26px 24px;
  border: 2px solid var(--ink);
  border-radius: 14px;
  background: var(--ink);
  color: var(--paper);
  font-family: system-ui, sans-serif;
  transition:
    transform var(--speed) cubic-bezier(.2, .8, .2, 1),
    box-shadow var(--speed) ease;
}

/* lift + acid ring */
.pk-card:hover,
.pk-card:focus-within {
  transform: translateY(calc(var(--lift) * -1));
  box-shadow:
    0 0 0 4px var(--accent),
    0 26px 40px -20px rgba(12, 12, 13, .55);
}

/* schuine ribbon in de hoek */
.pk-ribbon {
  position: absolute;
  top: 22px;
  right: -46px;
  width: 170px;
  padding: 6px 0;
  background: var(--accent);
  color: #0C0C0D;
  text-align: center;
  font: 800 12px/1 ui-monospace, Menlo, Consolas, monospace;
  letter-spacing: .12em;
  text-transform: uppercase;
  transform: rotate(40deg);
}

.pk-plan {
  margin: 0 0 6px;
  font: 700 13px/1 ui-monospace, Menlo, Consolas, monospace;
  letter-spacing: .1em;
  text-transform: uppercase;
  opacity: .75;
}

.pk-price {
  margin: 0 0 18px;
  font: 900 40px/1 "Arial Black", "Helvetica Neue", Impact, system-ui, sans-serif;
  font-variant-numeric: tabular-nums;
}

.pk-from,
.pk-per {
  font: 500 14px/1 system-ui, sans-serif;
  opacity: .75;
}

.pk-list {
  display: grid;
  gap: 10px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
  font-size: 15px;
}

.pk-list li {
  position: relative;
  padding-left: 26px;
}

/* vinkje uit twee randen */
.pk-list li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 2px;
  width: 6px;
  height: 12px;
  border-right: 3px solid var(--accent);
  border-bottom: 3px solid var(--accent);
  transform: rotate(45deg);
}

.pk-btn {
  display: block;
  padding: 13px 16px;
  border-radius: 8px;
  background: var(--accent);
  color: #0C0C0D;
  text-align: center;
  font-weight: 800;
  text-decoration: none;
  transition: background-color var(--speed) ease;
}

.pk-btn:hover {
  background: #F9F8F6;
}

.pk-btn:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .pk-card,
  .pk-btn {
    transition: none;
  }
  .pk-card:hover,
  .pk-card:focus-within {
    transform: none;
  }
}