* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: Arial, sans-serif;
  background: #f0f4f8;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* ── Header ── */
header {
  background: #0055a5;
  width: 100%;
  text-align: center;
  padding: 40px 24px 36px;
}

.gap-logo {
  font-size: 52px;
  font-weight: 900;
  letter-spacing: 10px;
  color: white;
  background: rgba(255,255,255,0.15);
  display: inline-block;
  padding: 10px 36px;
  border-radius: 10px;
  margin-bottom: 20px;
}

.event-title {
  font-size: 28px;
  color: white;
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 8px;
}

.event-sub {
  font-size: 17px;
  color: #cce0ff;
}

/* ── Grid ── */
main.hub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  padding: 48px 32px;
  max-width: 1100px;
  width: 100%;
}

/* ── Cards ── */
.activity-card {
  background: white;
  border-radius: 24px;
  padding: 36px 28px;
  text-decoration: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 12px;
  transition: all 0.25s;
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  border-bottom: 6px solid transparent;
  cursor: pointer;
}

.activity-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.14);
}

.card-blue   { border-bottom-color: #0055a5; }
.card-purple { border-bottom-color: #7c3aed; }
.card-green  { border-bottom-color: #16a34a; }
.card-orange { border-bottom-color: #ea580c; }
.card-pink   { border-bottom-color: #db2777; }

.card-emoji { font-size: 64px; line-height: 1; }

.card-title {
  font-size: 20px;
  font-weight: 900;
  color: #111;
}

.card-desc {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
  flex: 1;
}

.card-btn {
  margin-top: 8px;
  font-size: 14px;
  font-weight: 700;
  color: white;
  background: #0055a5;
  padding: 10px 24px;
  border-radius: 8px;
  transition: background 0.2s;
}

.card-blue:hover   .card-btn { background: #0044cc; }
.card-purple:hover .card-btn { background: #6d28d9; }
.card-green:hover  .card-btn { background: #15803d; }
.card-orange:hover .card-btn { background: #c2410c; }
.card-pink:hover   .card-btn { background: #be185d; }

.card-purple .card-btn { background: #7c3aed; }
.card-green  .card-btn { background: #16a34a; }
.card-orange .card-btn { background: #ea580c; }
.card-pink   .card-btn { background: #db2777; }

/* ── Footer ── */
footer {
  padding: 24px;
  color: #aaa;
  font-size: 13px;
  text-align: center;
}