body {
  margin: 0;
  height: 100vh;
  background: #000;
  color: #fff;
  font-family: monospace;

  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

h1 {
  font-size: 60px;
  margin-bottom: 10px;
}

p.sub {
  color: #777;
  margin-bottom: 40px;
}

/* GRID */
.container {
  width: 90%;
  max-width: 1100px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 25px;
}

/* CARD BASE */
.card {
  height: 180px;
  border: 2px solid white;
  display: flex;
  justify-content: center;
  align-items: center;

  text-decoration: none;
  color: white;
  font-size: 22px;

  position: relative;
  overflow: hidden;
}

/* TEXT */
.card span {
  position: relative;
  z-index: 2;
}

/* =========================
   ACTIVE MODULES
========================= */

.card.active:hover {
  color: lime;
  border-color: lime;
  box-shadow: 0 0 15px lime;
}

/* Media special effect */
.card.media.active::after {
  content: "[ REC ]";
  position: absolute;
  bottom: 10px;
  right: 10px;
  color: red;
  opacity: 0;
}

.card.media.active:hover::after {
  opacity: 1;
}

/* =========================
   NANOBOT CONSTRUCTION MODE
========================= */

.card.construction {
  border-color: #555;
  color: #aaa;
}

/* nanobot field */
.card.construction::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle, #fff 1px, transparent 1px);
  background-size: 14px 14px;
  opacity: 0;
  animation: swarm 2s linear infinite;
}

.card.construction:hover::before {
  opacity: 0.6;
}

/* overlay text */
.card.construction::after {
  content: "UNDER CONSTRUCTION";
  position: absolute;
  inset: 0;

  display: flex;
  justify-content: center;
  align-items: center;

  font-size: 13px;
  letter-spacing: 2px;

  background: rgba(0,0,0,0.6);
  opacity: 0;
}

.card.construction:hover::after {
  opacity: 1;
}

/* animation */
@keyframes swarm {
  0% { transform: translate(0,0); }
  50% { transform: translate(2px,-2px); }
  100% { transform: translate(0,0); }
}

/* MOBILE */
@media (max-width: 600px) {
  h1 { font-size: 40px; }
}