sytle.css
<style>
.border-box {
  border: 1px solid #8b0000; /* merah gelap */
  border-radius: 12px;
  padding: 15px;
  background-color: #140000;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 15px;
}

.border-box .card {
  flex: 1 1 calc(20% - 15px);
  max-width: 100px;
  aspect-ratio: 1 / 1;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  overflow: hidden;
  background: linear-gradient(145deg, #8b0000, #ff2a2a);
  box-shadow: 0 4px 12px rgba(255,0,0,0.35);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.border-box .card:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 8px 20px rgba(255,0,0,0.6);
}

.border-box .card img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

@media (max-width: 768px) {
  .border-box .card { flex: 1 1 calc(33.33% - 10px); }
}

@media (max-width: 480px) {
  .border-box .card { flex: 1 1 calc(50% - 10px); }
}

.prdx-wrapper {
  background: #0a0000;
  padding: 30px;
  border-radius: 20px;
  color: #fff;
  max-width: 750px;
  margin: auto;
  border: 1px solid rgba(255,0,0,0.35);
  box-shadow: 0 0 25px rgba(255,0,0,0.2);
  font-family: "Segoe UI", sans-serif;
}

.prdx-title {
  text-align: center;
  color: #ff2a2a;
  font-size: 30px;
  margin-bottom: 25px;
  text-shadow: 0 0 10px rgba(255,0,0,0.8);
}

.prdx-controls {
  display: flex;
  gap: 12px;
  margin-bottom: 25px;
}

.prdx-input {
  background: #1a0000;
  border: 1px solid rgba(255,0,0,0.35);
  border-radius: 10px;
  padding: 12px;
  color: #fff;
  width: 100%;
}

.prdx-btn {
  background: #ff2a2a;
  color: #fff;
  padding: 14px 20px;
  border-radius: 10px;
  cursor: pointer;
  border: none;
  font-weight: bold;
  transition: 0.25s;
}

.prdx-btn:hover {
  background: #ff4444;
}

.prdx-result {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  opacity: 0;
  transition: 0.5s ease-out;
}

.prdx-box {
  background: #1a0000;
  padding: 14px;
  border-radius: 12px;
  text-align: center;
  border: 1px solid rgba(255,0,0,0.25);
  box-shadow: 0 0 12px rgba(255,0,0,0.15);
  opacity: 0;
  transform: translateY(15px);
  transition: 0.5s;
}

.prdx-label {
  display: block;
  font-size: 13px;
  color: #ff2a2a;
  margin-bottom: 6px;
}

.prdx-num {
  font-size: 28px;
  font-weight: bold;
  letter-spacing: 3px;
  min-height: 34px;
  transition: 0.3s ease-in-out;
}

.prdx-num.glow {
  color: #ff2a2a;
  text-shadow: 0 0 12px #ff2a2a, 0 0 20px rgba(255,0,0,0.6);
}

.prdx-hacker-text {
  font-family: "Consolas", "Courier New", monospace;
  color: #ff2a2a;
  background: #1a0000;
  padding: 12px 18px;
  border-left: 3px solid #ff2a2a;
  border-radius: 6px;
  margin-bottom: 18px;
  font-size: 15px;
  text-shadow: 0 0 10px rgba(255,0,0,0.8);
  animation: prdxGlowRed 1.5s infinite alternate;
}

@keyframes prdxGlowRed {
  0% { opacity: 0.7; }
  100% { opacity: 1; }
}
</style>