:root {
  --bg-deep: #0b0e23;
  --bg-panel: #151a3a;
  --border-soft: #2b3164;
  --neon-blue: #4dd0ff;
  --neon-purple: #b98bff;
  --text-main: #eaf1ff;
  --text-muted: #9aa4d4;
  --star-color: #eaf6ff;
  --success: #4dff88;
  --danger: #ff5d6c;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(ellipse at top, #1a1f4d 0%, var(--bg-deep) 55%, #05061a 100%);
  color: var(--text-main);
  font-family: "Segoe UI", "Trebuchet MS", Roboto, Arial, sans-serif;
  position: relative;
  overflow-x: hidden;
}

#starfield {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

.site-header,
main,
.site-footer,
.game-header,
.game-layout {
  position: relative;
  z-index: 1;
}

.space-decor {
  position: fixed;
  inset: 0;
  overflow: hidden;
  z-index: 0;
  pointer-events: none;
}

.planet {
  position: absolute;
  border-radius: 50%;
}

.planet-ring {
  width: 220px;
  height: 220px;
  top: -70px;
  right: -60px;
  background: radial-gradient(circle at 32% 30%, #a5e6ff 0%, #4dd0ff 35%, #1c3a66 75%, #0b1636 100%);
  box-shadow: 0 0 70px rgba(77, 208, 255, 0.35);
  animation: planetDrift1 48s ease-in-out infinite;
}

.planet-ring::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300px;
  height: 80px;
  border: 7px solid rgba(165, 230, 255, 0.3);
  border-radius: 50%;
  transform: translate(-50%, -50%) rotate(-20deg);
}

.planet-moon {
  width: 130px;
  height: 130px;
  bottom: 6%;
  left: -55px;
  background: radial-gradient(circle at 35% 35%, #ffd9a0 0%, #ff9d4d 40%, #7a3b12 80%, #3a1c08 100%);
  box-shadow: 0 0 45px rgba(255, 157, 77, 0.25);
  animation: planetDrift2 36s ease-in-out infinite;
}

/* Roket kecil, terbang perlahan melintasi layar dari sudut ke sudut (bukan
   diam bergoyang di tempat) — muncul-hilang di tepi layar tiap siklus. */
.rocket {
  position: absolute;
  top: 0;
  left: 0;
  width: 26px;
  height: 26px;
  filter: drop-shadow(0 0 6px rgba(77, 208, 255, 0.6));
  animation: rocketFly 46s linear infinite;
  opacity: 0;
}

@keyframes planetDrift1 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(-40px, 30px); }
}

@keyframes planetDrift2 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(35px, -25px); }
}

@keyframes rocketFly {
  0%   { transform: translate(-8vw, 88vh) rotate(45deg); opacity: 0; }
  4%   { opacity: 0.9; }
  48%  { transform: translate(108vw, 6vh) rotate(45deg); opacity: 0.9; }
  52%  { opacity: 0; }
  52.1% { transform: translate(-8vw, 20vh) rotate(135deg); opacity: 0; }
  56%  { opacity: 0.9; }
  100% { transform: translate(108vw, 78vh) rotate(135deg); opacity: 0.9; }
}

@media (max-width: 700px) {
  .planet-ring {
    width: 140px;
    height: 140px;
  }
  .planet-moon {
    width: 90px;
    height: 90px;
  }
  .rocket {
    width: 20px;
    height: 20px;
  }
}

.site-header {
  text-align: center;
  padding: 48px 20px 24px;
}

.site-title {
  font-size: 2.6rem;
  margin: 0;
  letter-spacing: 1px;
  text-shadow: 0 0 18px rgba(77, 208, 255, 0.5);
}

.site-title .accent {
  color: var(--neon-blue);
}

.site-subtitle {
  margin: 8px 0 0;
  color: var(--text-muted);
  font-size: 1.05rem;
}

.game-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px 24px 60px;
}

@media (max-width: 900px) {
  .game-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .game-grid {
    grid-template-columns: 1fr;
  }
}

.game-card {
  display: block;
  position: relative;
  background: linear-gradient(160deg, var(--bg-panel), #10142e);
  border: 1px solid var(--border-soft);
  border-radius: 16px;
  padding: 24px 20px;
  text-decoration: none;
  color: var(--text-main);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.game-card:not(.locked):hover {
  transform: translateY(-4px);
  border-color: var(--neon-blue);
  box-shadow: 0 8px 28px rgba(77, 208, 255, 0.25);
}

.game-card.locked {
  opacity: 0.5;
  cursor: not-allowed;
  filter: grayscale(0.4);
}

.lock-icon {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 1.3rem;
}

.card-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 14px;
}

.card-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  filter: drop-shadow(0 0 8px rgba(77, 208, 255, 0.35));
}

.card-title {
  font-size: 1.2rem;
  margin: 0 0 6px;
  text-align: center;
}

.card-description {
  font-size: 0.9rem;
  color: var(--text-muted);
  text-align: center;
  min-height: 2.4em;
  margin: 0 0 14px;
}

.card-meta {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.difficulty-badge {
  color: #ffd23f;
  letter-spacing: 2px;
  font-size: 1.1rem;
}

.topic-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
}

.topic-badge {
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(185, 139, 255, 0.15);
  border: 1px solid var(--neon-purple);
  color: var(--neon-purple);
}

.site-footer {
  text-align: center;
  padding: 20px;
  color: var(--text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border-soft);
}